feat: Add skeleton loading UI components for various screens

- Implemented `Skeleton.kt` for loading placeholders in the app, including lesson cards, schedule, overview, and subjects.
- Introduced `Undo.kt` to manage undo actions with a snackbar interface.
- Created `WeekWidget.kt` for a widget displaying the week's schedule, including dynamic updates based on the current timetable.
- Added various splash animations in the `animator` directory for a smooth launch experience.
- Designed drawable resources for the widget and splash screen, including icons for city and room moves.
- Defined XML resources for widget configuration and photo paths.

README.md

@@ -173,6 +173,23 @@ npm run sync
 - В документах «Введение в высшее образование» строка «г. Полоцк, Дом офицеров» даёт занятию город, а место проведения остаётся в тексте.
 - Какие заметки показать над днём группы, решает общий модуль `shared/places.js`: им пользуются и `/api/timetable`, и PWA. Одинаковая заметка во всех подгруппах сводится к одной для всей группы, а заметка своей подгруппы показывается как заметка всего дня.
 
+**Занятия на выбор** (парсер 16). У 23‑, 24‑ и 25‑РГФ‑1 одна ячейка на всю группу содержит две пары сразу: «Немецкий язык (п.з) – Найверт Ю.О. 208А, / Французский язык (п.з.) – Глобенко М.В. 336Е». Это не подгруппы (ячейка не делится пополам): часть группы учит немецкий, часть французский. Так же записаны «Белорусский язык» и «Стилистика русского языка» у 26‑РГФ и две дисциплины по выбору у 23‑ИТ.
+- Ячейка, где каждая строка — целая пара (предмет, вид в скобках, преподаватель), делится на отдельные занятия со своими преподавателем и аудиторией (`parallel` в `server/parser.js`). Строка без предмета («321Д») остаётся при паре над ней. До версии 16 такая ячейка была одной парой «Немецкий язык» с двумя преподавателями и аудиторией французского.
+- Каждое такое занятие получает `option` — свой предмет, а документ — `choices` (`{groups, options}`). Тот же предмет в других ячейках этих групп («Немецкий язык» в четверг без французского) — тот же вариант и тоже получает `option`.
+- `/api/timetable` (API 15) отдаёт у занятия `option`, а у группы — `choices`: `[["Немецкий язык", "Французский язык"]]`. Клиент, который о них не знает, просто показывает обе пары.
+
+**Пары для иностранных студентов и для остальных** (парсер 17). «Русский язык как иностранный» и пары с пометкой «(для иностранных студентов)», «(для иностр.студ.)» — только для иностранцев, пары «(кроме иностр.студ.)» — только для остальных. Занятие получает `audience`: `"foreign"` или `"local"`.
+- Пометка — не часть названия и аудитории: раньше «ауд.36н (для иностранных студентов)» давало аудиторию «36н(дляиностранныхстудентов)».
+- В одной ячейке часто две пары сразу: иностранцы на РКИ, остальные на физкультуре или другом занятии. Такая ячейка делится на две, у каждой свой `audience`:
+  - «Ф и з и ч е с к а я к у л ь т у р а / Русский язык как иностранный (для иностранных студентов) …» (25‑ГЕО, 25‑КБ, 25‑ЭТ, 24‑СК, 24‑ЭБ);
+  - «Русский язык как иностранный (п.з.) Немирская В.А. 331Е ФИЗИЧЕСКАЯ КУЛЬТУРА» (25‑ и 26‑РГФ): раньше физкультура пропадала, а у РКИ не было аудитории;
+  - «3‑14н. Великая Отечественная война … 220Д / Русский язык как иностранный … 201Г»: раньше одна пара с аудиторией РКИ.
+  - «24‑КФ: Русский язык как иностранный …» в ячейке на 24‑КБ и 24‑КФ — занятие только 24‑КФ.
+- Город или время строкой выше («17.00 Новополоцк») и преподаватель строкой ниже — не отдельная пара.
+- Две пары, обе с пометкой («Теория языка (кроме иностр.студ.)» и «История языка (для иностр.студ.)» у 24‑РГФ‑1), — не выбор предмета, а пары для разных студентов.
+- В группах иностранцев («25‑ДОи», «24‑ТНГи‑2») РКИ — пара для всех, `audience` у неё нет.
+- `/api/timetable` отдаёт у занятия `audience`, а у группы — `audience: true`, если в ней есть такие пары.
+
 Для старых `.doc` на сервере нужен LibreOffice Writer (`soffice` в PATH или `LIBREOFFICE_BIN`). Конвертация может изменить сложное форматирование, результат нужно сверить. Реальные документы выбранного источника — `.docx`; поддержка `.doc` проверяется отдельно на образце, преобразованном LibreOffice.
 
 PDF, Excel, изображения и сканы пока не импортируются. Они не выдаются за распознанное расписание.
@@ -244,9 +261,22 @@ DOMAIN=schedule.example.by docker compose --profile https up -d --build
 
 Проверено на эмуляторе Pixel 10 Pro Fold (`OPENED`, `HALF_OPENED` в портрете и в альбомной ориентации) и на AVD «6.7in Foldable» (флип: телефонный макет). Универсальный AVD флипа сообщает приложению сгиб всегда в состоянии `FLAT`, поэтому «ноутбук» на флипе проверен только на фолде.
 
+- **Запуск.** Заставка (`core-splashscreen`, одинаково на Android 8–16): на фоне приложения рисуется иконка — календарь вырастает, кольца опускаются, зелёная галочка дорисовывается (около 750 мс, на Android 12+ анимированно). Заставка держится, пока не прочитаны сохранённые настройки, поэтому пустого кадра нет. Потом иконка раздувается и растворяется, а карточки «Обзора» поднимаются одна за другой (один раз за запуск).
+- **Отмена вместо подтверждений.** Удалённое задание или заметка и скрытая пара сразу пропадают, а снизу 10 секунд висит «Задание удалено · Вернуть» или «Скрыто: «…» · Вернуть». Фото удалённого задания стираются, только когда вернуть уже нельзя. В подробностях пары и в листе предмета snackbar показывается прямо в них.
+- **Сегодня — на текущей паре.** Страница сегодняшнего дня открывается на идущей паре (или следующей), а не на первой утренней.
+- **Виброотклик:** тик при выборе дня в ленте и при листании дней пальцем, при выборе в кнопках-переключателях. Подтверждение при выполнении задания и отметке посещения, щелчок у переключателей настроек.
+- **Скелетоны вместо спиннера:** пока грузится первое расписание группы, «Обзор», «Расписание» и «Предметы» показывают серые заготовки в форме своих карточек с мягким бликом. Так же выглядят занятия преподавателя или аудитории в поиске и каталог групп. Для TalkBack это одно «Загрузка». При системной настройке «Убрать анимацию» блик, появление карточек и прочие украшения отключаются.
+- **Карточка вырастает в подробности** (container transform). Пара открывается из своей карточки: из «Обзора», расписания по дням, недельной сетки, календаря «Планов» и подставки «ноутбука». Рамка плавно растягивается до полного экрана (на планшете — до большой панели по центру), картинка карточки растворяется, подробности проявляются. «Назад», предиктивный жест и касание за панелью сворачивают её обратно в карточку. Так же «+» в «Планах» и календаре раскрывается в лист нового задания; лист можно стянуть вниз за ручку.
+- **Живая текущая пара.** Вокруг идущей пары по часовой стрелке от левого верхнего угла рисуется рамка: какая часть пары прошла. Она подрастает плавно, без скачков. Цифры обратного отсчёта («ещё 44 мин», «Через 15 мин») прокручиваются, как на табло. Линия «сейчас» в недельной сетке ползёт вниз вместе со временем.
+- **Лента дней.** Выбранный день — один круг под всей лентой: при выборе другого дня он перетекает туда на пружинах, передний край спешит, задний догоняет, и по дороге круг вытягивается в каплю. В «Расписании» точка в круге дня значит «есть пары». Когда пролистываешь на другую неделю, её точки появляются по очереди, с понедельника.
+- **Выполненное задание.** При отметке текст зачёркивается слева направо, строка за строкой, и задание чуть задерживается на месте, прежде чем уйти к выполненным. Когда закрыто последнее открытое, у «Всё сделано» выскакивает галочка.
+- **Обновление жестом.** Потянуть вниз в «Обзоре» и в расписании: экспрессивный индикатор M3 с меняющейся формой и щелчок отклика, когда тянуть уже достаточно.
+- **Свежие изменения на виду.** Если университет перезалил документ и пары изменились или добавились, их карточки в расписании дважды вспыхивают цветом (один раз, при первом показе).
 - Первый запуск — короткий онбординг: приветствие с тремя возможностями приложения, затем шаги с волнистым индикатором прогресса: группа, подгруппа (только если группа делится на подгруппы) и напоминания. Разрешение на уведомления спрашивается на шаге напоминаний, его можно отложить; «Назад» (с предиктивным жестом) возвращает на предыдущий шаг. После онбординга открывается «Обзор» выбранной группы.
 - Обзор: отчёт за неделю (сколько пар прошло), следующие занятия сегодня с обратным отсчётом и ближайший учебный день.
 - Расписание группы по дням с листанием или недельной сеткой по часам; неделя и её цвет, номера пар, текущая пара, детали занятия с исходной записью Word. Если семестр не найден в таблице недель — строки Word по дням недели.
+- **Занятия на выбор** (немецкий или французский у РГФ). После выбора группы (и подгруппы) приложение спрашивает «Что вы изучаете?», в онбординге это отдельный шаг. Пары другого варианта скрываются из расписания, «Обзора», «Планов», виджетов, напоминаний и уведомлений. Изменить выбор можно в «Группах», в карточке «Сейчас открыта». Пока вариант не выбран, видны обе пары с меткой «на выбор».
+- **Иностранные студенты.** В группах, где есть пары только для иностранцев («Русский язык как иностранный») или только для остальных, приложение спрашивает «Вы иностранный студент?» (и в онбординге). Ответ «Да» скрывает пары «кроме иностранных студентов», «Нет» — РКИ и другие пары для иностранцев. Изменить — в «Группах», строка «Иностранный студент». На карточке пары — метка «для иностранных студентов» или «кроме иностранных студентов».
 - Предметы: пары по дням текущей недели; у каждого предмета — сокращение как в недельной сетке, следующее занятие с аудиторией, преподаватели и сколько пар на этой неделе. У каждого предмета свой постоянный цвет во всех разделах.
 - Планы: задания и заметки по дням — к занятию или общие, без привязки к паре, на выбранный день, просроченные сверху, «+» прикрепляет задание к ближайшему занятию. Три макета, как в School Planner: «Повестка дня» (все дни с липкими заголовками и полосой недели, которая следует за списком), «Список» (только дни с делами) и «Доска» (колонки дней). В настройках вида — пары дня и выполненные задания.
 - Календарь: месяц с отметками дней с парами и с планами, зелёные недели подсвечены; под ним лист с планами и парами выбранного дня. Лист можно поднять — месяц сворачивается до выбранной недели.
@@ -255,9 +285,11 @@ DOMAIN=schedule.example.by docker compose --profile https up -d --build
 - **Группа, которой больше нет.** Если сервер отвечает `group_not_found` или `document_not_found` — группу разделили («24‑ИЯ(РА)» стала «24‑ИЯ (РА)и‑1»…), или документ ушёл из каталога, — плашка с текстом сервера предлагает «Выбрать группу». Сохранённая копия остаётся на экране, а устаревшая группа убирается из недавних.
 - **Изменения в расписании.** Как в PWA: когда университет перезаливает документ группы, приложение сравнивает новое расписание с копией на устройстве. В «Обзоре» появляется карточка «Расписание обновлено · N изменений» с кнопкой «Показать», а в списке видно, что изменилось, что добавлено и что удалено, например «Аудитория: 374 → 375». Карточка показывается до просмотра или закрытия, последний список остаётся в настройках («Последние изменения»). Сравнение срабатывает и при фоновом обновлении (`SyncWorker`, раз в 6 часов). Если изменения нашлись в фоне, приходит уведомление «Расписание 23-АРХ изменилось» с первыми изменениями, например «Проектирование общественных зданий: аудитория 374 → 375». Уведомление локальное, сервер push для него не нужен. Его можно выключить в настройках («Изменения в расписании», по умолчанию включено), а на Android 13+ нужно разрешение на уведомления. Считается только новая версия того же файла: смена версии парсера или переход на другой документ изменениями не считаются. Сравниваются строки Word по дням недели и разовые занятия со своей датой, а не каждая рассчитанная дата.
 - Задания и заметки к паре: из карточки занятия — к этой паре или к следующей паре того же предмета. Задания отмечаются выполненными, просроченные подсвечиваются; список — в «Обзоре», по предмету — в «Предметах», точка на блоке в недельной сетке. Хранятся только на устройстве (`notes.json`) и привязаны к группе.
+- **Фото к заданиям:** в редакторе задания или заметки — «Снять» (приложение камеры) и «Галерея» (системный выбор фото, без доступа к памяти), до 6 фото. Фото уменьшается до 2048 px по длинной стороне, поворачивается по EXIF и хранится в `files/photos/` рядом с заметками. Удаление фото, задания или отмена правки убирает файлы, а при запуске удаляются фото, на которые не ссылается ни одна заметка. В списках у задания миниатюра (с «+N»), на карточке пары — значок фото. Просмотр — на весь экран, с листанием, масштабом щипком и двойным касанием. Задание может быть и одним фото, без текста.
 - Посещаемость: «был» или «пропустил» в карточке занятия и одним касанием в «Обзоре» для прошедших сегодня пар; статистика по каждому предмету в «Предметах». Хранится на устройстве (`attendance.json`).
 - Скрытие занятий: «Скрыть такие занятия» в карточке занятия убирает предмет с этим типом занятия из расписания, обзора, виджетов и напоминаний; вернуть можно в настройках.
 - Второй виджет «Следующая пара» (4×1) и плитка в шторке быстрых настроек с текущей или следующей парой и аудиторией.
+- **Виджет «Неделя»** (4×2 и больше): номер и цвет недели, по плитке на день (Пн–Сб, воскресенье — только если в нём есть пары) с числом пар. Сегодня выделено. Значок города — день в другом городе, значок стрелок — перенос аудитории, внизу строка вроде «Полоцк: вт, пт · перенос: пн, чт». Если растянуть виджет в высоту, в плитках появляются сокращения пар, как в недельной сетке. В воскресенье виджет показывает следующую неделю. Нажатие на день открывает этот день, на заголовок — неделю.
 - Настройки отображения: цвета предметов, преподаватели, аудитории, номера пар, метки занятий и пометки из Word можно скрыть; полные сведения остаются в карточке занятия.
 - Группы (кнопка группы в верхней панели «Обзора»; если у группы есть подгруппы, после выбора приложение предложит свою): поиск по номеру во всём каталоге, недавние, каталог по факультету и курсу, выбор подгруппы.
 - Поиск по университету: занятия преподавателя или аудитории на выбранный день.

android/app/build.gradle.kts

@@ -59,6 +59,7 @@ dependencies {
     implementation(libs.lifecycle.viewmodel.compose)
     implementation(libs.lifecycle.runtime.compose)
     implementation(libs.core.ktx)
+    implementation(libs.splashscreen)
     implementation(libs.coroutines.android)
     implementation(libs.serialization.json)
     implementation(libs.okhttp)

android/app/src/main/AndroidManifest.xml

@@ -23,6 +23,7 @@
             android:name=".MainActivity"
             android:exported="true"
             android:launchMode="singleTop"
+            android:theme="@style/Theme.PsuSchedule.Starting"
             android:windowSoftInputMode="adjustResize">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
@@ -58,6 +59,18 @@
                 android:resource="@xml/next_widget_info" />
         </receiver>
 
+        <receiver
+            android:name=".widget.WeekWidgetReceiver"
+            android:exported="true"
+            android:label="@string/week_widget_name">
+            <intent-filter>
+                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
+            </intent-filter>
+            <meta-data
+                android:name="android.appwidget.provider"
+                android:resource="@xml/week_widget_info" />
+        </receiver>
+
         <service
             android:name=".tile.LessonTileService"
             android:exported="true"
@@ -69,6 +82,17 @@
             </intent-filter>
         </service>
 
+        <!-- The camera app saves a photo for a task here (ui/Photos.kt). -->
+        <provider
+            android:name="androidx.core.content.FileProvider"
+            android:authorities="${applicationId}.photos"
+            android:exported="false"
+            android:grantUriPermissions="true">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/photo_paths" />
+        </provider>
+
         <receiver
             android:name=".notify.ReminderReceiver"
             android:exported="false" />

android/app/src/main/kotlin/org/xtimms/psu/schedule/Launch.kt

@@ -33,16 +33,20 @@ sealed interface Launch {
             }
         }
 
+        /** The intent of a target: "day" with its [date], "week", "today", "search" or "task". */
+        fun intent(context: Context, target: String, date: LocalDate? = null): Intent =
+            Intent(context, MainActivity::class.java)
+                .setAction(ACTION)
+                .putExtra(TARGET, target)
+                .apply { date?.let { putExtra(DATE, it.toString()) } }
+                .addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP)
+
         /** Opens a day of the timetable, for a notification about it. */
         fun day(context: Context, date: LocalDate, request: Int): PendingIntent =
             PendingIntent.getActivity(
                 context,
                 request,
-                Intent(context, MainActivity::class.java)
+                intent(context, "day", date),
-                    .setAction(ACTION)
-                    .putExtra(TARGET, "day")
-                    .putExtra(DATE, date.toString())
-                    .addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP),
                 PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE,
             )
     }

android/app/src/main/kotlin/org/xtimms/psu/schedule/MainActivity.kt

@@ -6,6 +6,11 @@ import androidx.compose.foundation.gestures.draggable
 import androidx.compose.foundation.gestures.Orientation
 import kotlin.coroutines.cancellation.CancellationException
 import androidx.compose.runtime.LaunchedEffect
+import androidx.core.splashscreen.SplashScreen.Companion.installSplashScreen
+import org.xtimms.psu.schedule.ui.UndoArea
+import org.xtimms.psu.schedule.ui.LocalMorph
+import org.xtimms.psu.schedule.ui.MorphHost
+import org.xtimms.psu.schedule.ui.MorphOverlay
 import androidx.compose.animation.core.Animatable
 import androidx.compose.animation.core.rememberTransition
 import androidx.compose.animation.core.SeekableTransitionState
@@ -160,6 +165,17 @@ class MainActivity : ComponentActivity() {
     }
 
     override fun onCreate(savedInstanceState: Bundle?) {
+        // The launch screen stays until the stored settings are read, so a returning student
+        // never sees an empty frame; then the icon swells and fades into the app.
+        val splash = installSplashScreen()
+        splash.setKeepOnScreenCondition { vm.settings.value == null }
+        splash.setOnExitAnimationListener { provider ->
+            val icon = provider.iconView
+            icon.animate().scaleX(1.15f).scaleY(1.15f).alpha(0f).setDuration(250L)
+                .setInterpolator(android.view.animation.PathInterpolator(0.3f, 0f, 0.8f, 0.15f)).start()
+            provider.view.animate().alpha(0f).setStartDelay(100L).setDuration(250L)
+                .withEndAction { provider.remove() }.start()
+        }
         super.onCreate(savedInstanceState)
         // A recreated activity (rotation) must not open the same screen again.
         if (savedInstanceState == null) launch.value = Launch.of(intent)
@@ -261,6 +277,10 @@ private fun App(vm: MainViewModel, firstRun: Boolean, launch: Launch?, onLaunche
     val slide = rememberSlideDistance()
 
     // Behind the pushed-aside screen: the menu's own card-white background.
+    // "Задание удалено · Вернуть" and the like, over every screen (Undo.kt).
+    val morph = remember { MorphHost() }
+    UndoArea(Modifier.fillMaxSize()) {
+    androidx.compose.runtime.CompositionLocalProvider(LocalMorph provides morph) {
     BoxWithConstraints(Modifier.fillMaxSize().background(MaterialTheme.colorScheme.card)) {
         val wide = maxWidth >= MEDIUM_WIDTH
         // An open book-style foldable gets the tablet layout; a flip phone keeps the phone one.
@@ -515,6 +535,10 @@ private fun App(vm: MainViewModel, firstRun: Boolean, launch: Launch?, onLaunche
             }
         }
     }
+    // A card's details and the "+" sheet open over everything, growing from what was tapped.
+    MorphOverlay(morph)
+    }
+    }
 }
 
 /** What the menu shows and where its items lead. */

android/app/src/main/kotlin/org/xtimms/psu/schedule/ScheduleApp.kt

@@ -1,6 +1,7 @@
 package org.xtimms.psu.schedule
 
 import android.app.Application
+import kotlinx.coroutines.launch
 import org.xtimms.psu.schedule.data.Api
 import org.xtimms.psu.schedule.data.AttendanceStore
 import org.xtimms.psu.schedule.data.NotesStore
@@ -30,6 +31,8 @@ class ScheduleApp : Application() {
         org.xtimms.psu.schedule.notify.DayAlerts.createChannel(this)
         org.xtimms.psu.schedule.notify.LiveLesson.createChannel(this)
         SyncWorker.schedule(this)
+        // Before any editor opens: photos left by an edit that never got saved.
+        kotlinx.coroutines.CoroutineScope(kotlinx.coroutines.Dispatchers.IO).launch { notes.sweep() }
     }
 }
 

android/app/src/main/kotlin/org/xtimms/psu/schedule/data/Models.kt

@@ -12,6 +12,10 @@ data class Timetable(
     val semester: Semester? = null,
     val note: String? = null,
     val subgroups: List<String> = emptyList(),
+    /** What parts of the group choose between: [["Немецкий язык", "Французский язык"]]. */
+    val choices: List<List<String>> = emptyList(),
+    /** Some lessons are for foreign students only ([Lesson.audience]), so the student may say which they are. */
+    val audience: Boolean = false,
     val bells: List<Bell> = emptyList(),
     val from: String,
     val days: List<Day> = emptyList(),
@@ -81,6 +85,10 @@ data class Lesson(
     val condition: String = "",
     val variant: String = "all",
     val subgroup: String? = null,
+    /** "Немецкий язык": the lesson of the part of the group that took this option (see [Timetable.choices]). */
+    val option: String? = null,
+    /** "foreign": for foreign students only (Russian as a foreign language); "local": for the others. */
+    val audience: String? = null,
     val groups: List<String> = emptyList(),
     val uncertain: Boolean = false,
     val raw: String = "",
@@ -89,6 +97,24 @@ data class Lesson(
 /** A recurring lesson the student may hide: the subject with its kind, in every week. */
 val Lesson.hideKey: String get() = subject.trim().lowercase() + "|" + type.trim().lowercase()
 
+/** How a choice's option the student did not take sits among the hidden lessons. */
+const val OPTION_PREFIX = "option|"
+
+fun optionKey(option: String): String = OPTION_PREFIX + option.trim().lowercase()
+
+/** How the lessons for foreign students, or for the others, sit among the hidden ones. */
+const val AUDIENCE_PREFIX = "audience|"
+
+/**
+ * Hidden by the student, the lesson of another option than theirs (German when they study
+ * French), or one for foreign students when they are not (and the other way round).
+ */
+fun Lesson.hiddenIn(hidden: Set<String>): Boolean =
+    hideKey in hidden || (option != null && optionKey(option) in hidden) || (audience != null && AUDIENCE_PREFIX + audience in hidden)
+
+/** One choice of a group, the same whatever order the document lists its options in. */
+fun choiceKey(options: List<String>): String = options.map { it.trim().lowercase() }.sorted().joinToString("|")
+
 /** A room label with the lesson's town when the document names one: "ауд. 203Г · Полоцк", or the town alone. */
 fun withPlace(room: String?, place: String?): String? =
     listOfNotNull(room?.takeIf { it.isNotEmpty() }, place).joinToString(" · ").ifEmpty { null }

android/app/src/main/kotlin/org/xtimms/psu/schedule/data/Notes.kt

@@ -1,6 +1,11 @@
 package org.xtimms.psu.schedule.data
 
 import android.content.Context
+import android.graphics.Bitmap
+import android.graphics.BitmapFactory
+import android.graphics.Matrix
+import android.media.ExifInterface
+import android.net.Uri
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
@@ -27,13 +32,16 @@ data class Note(
     val task: Boolean = true,
     val done: Boolean = false,
     val created: Long = System.currentTimeMillis(),
+    /** Photos of the board or the assignment: file names in [NotesStore.photos]. */
+    val photos: List<String> = emptyList(),
 )
 
 fun groupKey(g: SavedGroup) = "${g.docId}|${g.group}"
 
-/** Notes live only on the device, in one small JSON file. */
+/** Notes live only on the device, in one small JSON file; their photos in a folder beside it. */
-class NotesStore(context: Context) {
+class NotesStore(private val context: Context) {
     private val file = File(context.filesDir, "notes.json")
+    val photos = File(context.filesDir, "photos")
     private val lock = Mutex()
     private val _notes = MutableStateFlow(read())
     val notes: StateFlow<List<Note>> = _notes
@@ -50,10 +58,77 @@ class NotesStore(context: Context) {
     }
 
     suspend fun save(note: Note) = change { list ->
+        // Photos taken out of the note go from the disk too.
+        list.firstOrNull { it.id == note.id }?.let { discard(it.photos - note.photos.toSet()) }
         if (list.any { it.id == note.id }) list.map { if (it.id == note.id) note else it } else list + note
     }
 
-    suspend fun delete(id: String) = change { list -> list.filterNot { it.id == id } }
+    suspend fun delete(id: String) = change { list ->
+        list.firstOrNull { it.id == id }?.let { discard(it.photos) }
+        list.filterNot { it.id == id }
+    }
+
+    /** Takes a note out of the list but keeps its photos, so "Вернуть" can bring it back whole. */
+    suspend fun remove(id: String): Note? {
+        var removed: Note? = null
+        change { list ->
+            removed = list.firstOrNull { it.id == id }
+            list.filterNot { it.id == id }
+        }
+        return removed
+    }
+
+    fun photo(name: String) = File(photos, name)
+
+    /**
+     * A picked or taken picture, kept as a JPEG of at most [MAX_SIDE] px on its long side and
+     * turned upright: a phone photo of a board is a few hundred kilobytes, not several megabytes.
+     * Returns the file name, or null when the picture cannot be read.
+     */
+    suspend fun importPhoto(uri: Uri): String? = withContext(Dispatchers.IO) {
+        runCatching {
+            val resolver = context.contentResolver
+            val bounds = BitmapFactory.Options().apply { inJustDecodeBounds = true }
+            resolver.openInputStream(uri)?.use { BitmapFactory.decodeStream(it, null, bounds) }
+            var sample = 1
+            while (maxOf(bounds.outWidth, bounds.outHeight) / (sample * 2) >= MAX_SIDE) sample *= 2
+            val decoded = resolver.openInputStream(uri)?.use {
+                BitmapFactory.decodeStream(it, null, BitmapFactory.Options().apply { inSampleSize = sample })
+            } ?: return@runCatching null
+            val rotation = resolver.openInputStream(uri)?.use {
+                when (ExifInterface(it).getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL)) {
+                    ExifInterface.ORIENTATION_ROTATE_90 -> 90f
+                    ExifInterface.ORIENTATION_ROTATE_180 -> 180f
+                    ExifInterface.ORIENTATION_ROTATE_270 -> 270f
+                    else -> 0f
+                }
+            } ?: 0f
+            val scale = minOf(1f, MAX_SIDE.toFloat() / maxOf(decoded.width, decoded.height))
+            val matrix = Matrix().apply { postScale(scale, scale); postRotate(rotation) }
+            val upright = Bitmap.createBitmap(decoded, 0, 0, decoded.width, decoded.height, matrix, true)
+            photos.mkdirs()
+            val name = UUID.randomUUID().toString() + ".jpg"
+            photo(name).outputStream().use { upright.compress(Bitmap.CompressFormat.JPEG, 85, it) }
+            name
+        }.getOrNull()
+    }
+
+    /** Removes photo files: of a deleted note, or added to a note that was never saved. */
+    fun discard(names: Collection<String>) {
+        names.forEach { photo(it).delete() }
+    }
+
+    /** Photos no note refers to any more, after a crash mid-edit, for example. */
+    suspend fun sweep() = withContext(Dispatchers.IO) {
+        lock.withLock {
+            val used = _notes.value.flatMap { it.photos }.toSet()
+            photos.listFiles()?.filter { it.name !in used }?.forEach { it.delete() }
+        }
+    }
+
+    private companion object {
+        const val MAX_SIDE = 2048
+    }
 
     suspend fun toggle(id: String) = change { list -> list.map { if (it.id == id) it.copy(done = !it.done) else it } }
 }

android/app/src/main/kotlin/org/xtimms/psu/schedule/data/Repository.kt

@@ -27,6 +27,13 @@ class Repository(context: Context, val api: Api, private val settings: Settings)
     private val _changes = MutableStateFlow(readChanges())
     val changes: StateFlow<List<ScheduleChanges>> = _changes
 
+    // Lessons just added or changed by a republished document: their cards glow once when shown.
+    private val _fresh = MutableStateFlow<Set<String>>(emptySet())
+    val fresh: StateFlow<Set<String>> = _fresh
+    fun freshShown(key: String) {
+        _fresh.value = _fresh.value - key
+    }
+
     private fun readChanges(): List<ScheduleChanges> =
         runCatching { json.decodeFromString<List<ScheduleChanges>>(changesCache.readText()) }.getOrDefault(emptyList())
 
@@ -58,6 +65,7 @@ class Repository(context: Context, val api: Api, private val settings: Settings)
             changed = changed,
         )
         writeChanges((listOf(record) + _changes.value.filter { it.document != record.document || it.group != record.group }).take(12))
+        _fresh.value = (added.map { it.lesson.key } + changed.map { it.after.lesson.key }).toSet()
     }
 
     /** The overview's card was opened or closed: the record stays for "Последние изменения". */
@@ -110,7 +118,7 @@ class Repository(context: Context, val api: Api, private val settings: Settings)
     fun lessonsOn(timetable: Timetable, date: LocalDate, subgroup: String?, hidden: Set<String> = emptySet()): List<Lesson> =
         timetable.days.firstOrNull { it.date == date.toString() }?.lessons.orEmpty()
             .filter { subgroup == null || it.subgroup == null || it.subgroup == subgroup }
-            .filter { it.hideKey !in hidden }
+            .filter { !it.hiddenIn(hidden) }
 
     fun dayOf(timetable: Timetable, date: LocalDate): Day? =
         timetable.days.firstOrNull { it.date == date.toString() }

android/app/src/main/kotlin/org/xtimms/psu/schedule/data/Settings.kt

@@ -58,8 +58,15 @@ data class UserSettings(
     val liveLesson: Boolean = false,
     val recent: List<SavedGroup> = emptyList(),
     val display: Display = Display(),
-    /** Lessons hidden in the open group, as [Lesson.hideKey]s. */
+    /**
+     * Lessons hidden in the open group, as [Lesson.hideKey]s, and the options of its choices the
+     * student did not take, as [optionKey]s.
+     */
     val hidden: Set<String> = emptySet(),
+    /** The open group's choices ([choiceKey]) and the option taken in each: "Французский язык". */
+    val choices: Map<String, String> = emptyMap(),
+    /** Whether the student is a foreign student in the open group; null: show every lesson. */
+    val foreign: Boolean? = null,
     val plans: PlansPrefs = PlansPrefs(),
 )
 
@@ -70,6 +77,8 @@ class Settings(private val context: Context) {
     private object Keys {
         val current = stringPreferencesKey("current")
         val subgroups = stringPreferencesKey("subgroups")
+        val choices = stringPreferencesKey("choices")
+        val foreign = stringPreferencesKey("foreign")
         val theme = stringPreferencesKey("theme")
         val dynamic = booleanPreferencesKey("dynamic_color")
         val reminders = booleanPreferencesKey("reminders")
@@ -94,6 +103,12 @@ class Settings(private val context: Context) {
         val plansDone = booleanPreferencesKey("plans_done")
     }
 
+    private fun Preferences.choiceMap(): Map<String, Map<String, String>> =
+        this[Keys.choices]?.let { runCatching { json.decodeFromString<Map<String, Map<String, String>>>(it) }.getOrNull() }.orEmpty()
+
+    private fun Preferences.foreignMap(): Map<String, Boolean> =
+        this[Keys.foreign]?.let { runCatching { json.decodeFromString<Map<String, Boolean>>(it) }.getOrNull() }.orEmpty()
+
     private fun Preferences.hiddenMap(): Map<String, List<String>> =
         this[Keys.hidden]?.let { runCatching { json.decodeFromString<Map<String, List<String>>>(it) }.getOrNull() }.orEmpty()
 
@@ -106,6 +121,14 @@ class Settings(private val context: Context) {
         val subgroups = this[Keys.subgroups]?.let {
             runCatching { json.decodeFromString<Map<String, String>>(it) }.getOrNull()
         }.orEmpty()
+        val choices = current?.let { choiceMap()[subgroupKey(it)] }.orEmpty()
+        val foreign = current?.let { foreignMap()[subgroupKey(it)] }
+        // A foreign student does not see the others' lessons, and the other way round.
+        val audience = when (foreign) {
+            true -> setOf(AUDIENCE_PREFIX + "local")
+            false -> setOf(AUDIENCE_PREFIX + "foreign")
+            null -> emptySet()
+        }
         return UserSettings(
             current = current,
             subgroup = current?.let { subgroups[subgroupKey(it)] },
@@ -123,7 +146,9 @@ class Settings(private val context: Context) {
             recent = this[Keys.recent]?.let {
                 runCatching { json.decodeFromString<List<SavedGroup>>(it) }.getOrNull()
             }.orEmpty(),
-            hidden = current?.let { hiddenMap()[subgroupKey(it)] }.orEmpty().toSet(),
+            hidden = current?.let { hiddenMap()[subgroupKey(it)] }.orEmpty().toSet() + skipped(choices) + audience,
+            choices = choices,
+            foreign = foreign,
             plans = PlansPrefs(
                 layout = this[Keys.plansLayout]?.let { runCatching { PlansLayout.valueOf(it) }.getOrNull() } ?: PlansLayout.Agenda,
                 lessons = this[Keys.plansLessons] ?: false,
@@ -142,6 +167,10 @@ class Settings(private val context: Context) {
 
     private fun subgroupKey(g: SavedGroup) = "${g.docId}|${g.group}"
 
+    /** The options not taken: their lessons are hidden like the ones the student hid. */
+    private fun skipped(choices: Map<String, String>): Set<String> =
+        choices.flatMap { (key, taken) -> key.split("|").filter { it != taken.trim().lowercase() }.map(::optionKey) }.toSet()
+
     suspend fun openGroup(group: SavedGroup) = context.store.edit { prefs ->
         prefs[Keys.current] = json.encodeToString(group)
         val recent = prefs[Keys.recent]?.let {
@@ -169,6 +198,26 @@ class Settings(private val context: Context) {
         prefs[Keys.subgroups] = json.encodeToString(map.toMap())
     }
 
+    /** The option the student takes in a choice of the open group ([option] null: all of them). */
+    suspend fun setChoice(options: List<String>, option: String?) = context.store.edit { prefs ->
+        val current = prefs[Keys.current]?.let { runCatching { json.decodeFromString<SavedGroup>(it) }.getOrNull() }
+            ?: return@edit
+        val all = prefs.choiceMap().toMutableMap()
+        val mine = all[subgroupKey(current)].orEmpty().toMutableMap()
+        if (option == null) mine.remove(choiceKey(options)) else mine[choiceKey(options)] = option
+        all[subgroupKey(current)] = mine
+        prefs[Keys.choices] = json.encodeToString(all.toMap())
+    }
+
+    /** Whether the student is a foreign student in the open group; null forgets the answer. */
+    suspend fun setForeign(foreign: Boolean?) = context.store.edit { prefs ->
+        val current = prefs[Keys.current]?.let { runCatching { json.decodeFromString<SavedGroup>(it) }.getOrNull() }
+            ?: return@edit
+        val map = prefs.foreignMap().toMutableMap()
+        if (foreign == null) map.remove(subgroupKey(current)) else map[subgroupKey(current)] = foreign
+        prefs[Keys.foreign] = json.encodeToString(map.toMap())
+    }
+
     suspend fun setTheme(mode: ThemeMode) = context.store.edit { it[Keys.theme] = mode.name }
     suspend fun setDynamicColor(on: Boolean) = context.store.edit { it[Keys.dynamic] = on }
     suspend fun setReminders(on: Boolean) = context.store.edit { it[Keys.reminders] = on }

android/app/src/main/kotlin/org/xtimms/psu/schedule/notify/Reminders.kt

@@ -1,6 +1,6 @@
 package org.xtimms.psu.schedule.notify
 
-import org.xtimms.psu.schedule.data.hideKey
+import org.xtimms.psu.schedule.data.hiddenIn
 import org.xtimms.psu.schedule.data.withPlace
 import org.xtimms.psu.schedule.data.forSubgroup
 import android.Manifest
@@ -79,7 +79,7 @@ object Reminders {
             val date = parseDate(day.date)
             val shown = day.lessons
                 .filter { settings.subgroup == null || it.subgroup == null || it.subgroup == settings.subgroup }
-                .filter { it.hideKey !in settings.hidden }
+                .filter { !it.hiddenIn(settings.hidden) }
             // A day in another town: the first lesson is announced earlier, for the road.
             val away = settings.travelAlerts && day.places.forSubgroup(settings.subgroup).isNotEmpty()
             val first = shown.minOfOrNull { it.start }

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Attendance.kt

@@ -2,6 +2,8 @@
 
 package org.xtimms.psu.schedule.ui
 
+import androidx.compose.ui.platform.LocalHapticFeedback
+import androidx.compose.ui.hapticfeedback.HapticFeedbackType
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
@@ -83,6 +85,7 @@ fun LessonAttendance(vm: MainViewModel, lesson: Lesson, date: LocalDate) {
 @Composable
 fun AttendanceCard(vm: MainViewModel, slots: List<Slot>) {
     val marks by vm.marks.collectAsStateWithLifecycle()
+    val haptic = LocalHapticFeedback.current
     if (vm.currentGroupKey() == null) return
     val now = nowTime()
     val date = today()
@@ -103,11 +106,17 @@ fun AttendanceCard(vm: MainViewModel, slots: List<Slot>) {
                     Text(lesson.subject, style = MaterialTheme.typography.bodyLargeEmphasized, maxLines = 2, overflow = TextOverflow.Ellipsis)
                     TimeText("${slot.start} → ${slot.end}", style = MaterialTheme.typography.bodyMedium, color = MaterialTheme.colorScheme.onSurfaceVariant)
                 }
-                FilledTonalIconButton(onClick = { vm.mark(lesson, date, true) }) {
+                FilledTonalIconButton(onClick = {
+                    haptic.performHapticFeedback(HapticFeedbackType.Confirm)
+                    vm.mark(lesson, date, true)
+                }) {
                     Icon(Icons.Rounded.Check, contentDescription = "Был на паре «${lesson.subject}»")
                 }
                 FilledTonalIconButton(
-                    onClick = { vm.mark(lesson, date, false) },
+                    onClick = {
+                        haptic.performHapticFeedback(HapticFeedbackType.Confirm)
+                        vm.mark(lesson, date, false)
+                    },
                     colors = IconButtonDefaults.filledTonalIconButtonColors(
                         containerColor = MaterialTheme.colorScheme.errorContainer,
                         contentColor = MaterialTheme.colorScheme.onErrorContainer,

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/CalendarScreen.kt

@@ -123,13 +123,14 @@ private fun weekRow(month: YearMonth, d: LocalDate) = mondays(month).indexOf(d.m
  */
 @Composable
 fun CalendarScreen(vm: MainViewModel, nav: AppNav) {
+    val undo = LocalUndo.current
     val timetable by vm.timetable.collectAsStateWithLifecycle()
     val settings by vm.settings.collectAsStateWithLifecycle()
     val notes by vm.notes.collectAsStateWithLifecycle()
     var selected by remember { mutableStateOf(today()) }
-    var details by remember { mutableStateOf<Pair<Lesson, LocalDate>?>(null) }
+    val openLesson = rememberLessonOpener(vm)
     var editing by remember { mutableStateOf<Note?>(null) }
-    var adding by remember { mutableStateOf(false) }
+    val morph = LocalMorph.current
     var target by remember { mutableStateOf<NoteTarget?>(null) }
     val base = remember { YearMonth.from(today()).minusMonths(MONTHS_BEFORE.toLong()) }
     val pager = rememberPagerState(initialPage = MONTHS_BEFORE) { MONTHS }
@@ -254,7 +255,7 @@ fun CalendarScreen(vm: MainViewModel, nav: AppNav) {
     val agenda: @Composable (Modifier) -> Unit = { modifier ->
         DayAgenda(
             vm, t, subgroup, selected, notes,
-            onLesson = { details = it to selected },
+            onLesson = { openLesson(it, selected) },
             onNote = { editing = it },
             modifier = modifier,
         )
@@ -304,15 +305,23 @@ fun CalendarScreen(vm: MainViewModel, nav: AppNav) {
                 }
             }
         }
+        // "+" grows into the sheet of a new plan for the chosen day (Morph.kt).
         FloatingActionButton(
-            onClick = { adding = true },
+            onClick = {
-            modifier = Modifier.align(Alignment.BottomEnd).padding(end = 16.dp, bottom = 16.dp + navBarPadding()),
+                morph?.open(MorphKind.Sheet) { close ->
+                    AddPlanSheet(vm, t, subgroup, day = selected) {
+                        close()
+                        target = it
+                    }
+                }
+            },
+            modifier = Modifier
+                .align(Alignment.BottomEnd)
+                .padding(end = 16.dp, bottom = 16.dp + navBarPadding())
+                .morphOrigin("fab|calendar", MaterialTheme.colorScheme.primaryContainer, 16.dp),
         ) { Icon(Icons.Rounded.Add, contentDescription = "Новый план") }
     }
 
-    if (adding) ModalBottomSheet(onDismissRequest = { adding = false }) {
-        AddPlanSheet(vm, t, subgroup, day = selected) { adding = false; target = it }
-    }
     target?.let { tg ->
         vm.currentGroupKey()?.let { group ->
             NoteEditor(
@@ -325,18 +334,13 @@ fun CalendarScreen(vm: MainViewModel, nav: AppNav) {
             )
         }
     }
-    details?.let { (lesson, date) ->
-        ModalBottomSheet(onDismissRequest = { details = null }) {
-            LessonDetails(lesson, t?.bells.orEmpty(), date, vm, onClose = { details = null })
-        }
-    }
     editing?.let { note ->
         NoteEditor(
             target = null,
             editing = note,
             groupKey = note.group,
             onSave = { vm.saveNote(it); editing = null },
-            onDelete = { vm.deleteNote(it.id); editing = null },
+            onDelete = { vm.deleteNote(it.id, undo); editing = null },
             onDismiss = { editing = null },
         )
     }
@@ -504,11 +508,22 @@ private fun DayAgendaContent(
                 item(key = "plans") { AnimatedItem { Section(number, "Ваши планы", trailing = date.format(DATE)) } }
                 plans.forEachIndexed { i, note ->
                     item(key = note.id) { AnimatedItem {
+                        // Struck through in place first, then the list moves it down.
+                        var shownDone by remember(note.id, note.done) { mutableStateOf(note.done) }
+                        val scope = rememberCoroutineScope()
                         TimelineItem(
-                            marker = { PlanMarker(note, onToggle = { vm.toggleNote(note.id) }) },
+                            marker = {
+                                PlanMarker(note.copy(done = shownDone), onToggle = {
+                                    shownDone = !shownDone
+                                    if (shownDone) scope.launch {
+                                        kotlinx.coroutines.delay(DONE_PAUSE)
+                                        vm.toggleNote(note.id)
+                                    } else vm.toggleNote(note.id)
+                                })
+                            },
                             over = note.subject.ifBlank { null },
                             title = note.text,
-                            done = note.task && note.done,
+                            done = note.task && shownDone,
                             last = i == plans.lastIndex,
                             onClick = { onNote(note) },
                         )
@@ -540,6 +555,7 @@ private fun DayAgendaContent(
                             ).joinToString(" · ").ifEmpty { null },
                             last = i == lessons.lastIndex,
                             onClick = { onLesson(l) },
+                            origin = Modifier.morphOrigin("cal|$date|${l.key}|${l.start}", MaterialTheme.colorScheme.surfaceContainerLow, 16.dp),
                         )
                     }
                 }
@@ -593,6 +609,8 @@ private fun TimelineItem(
     overColor: Color? = null,
     last: Boolean,
     onClick: () -> Unit,
+    /** For a lesson: where its details page grows from. */
+    origin: Modifier = Modifier,
 ) {
     val line = MaterialTheme.colorScheme.outlineVariant
     // Level with the first line of the title: 14dp padding, a 20dp line above it, a 24dp title line.
@@ -601,6 +619,7 @@ private fun TimelineItem(
         Modifier
             .fillMaxWidth()
             .height(IntrinsicSize.Min)
+            .then(origin)
             .clip(MaterialTheme.shapes.large)
             .clickable(onClickLabel = "Подробнее", role = Role.Button, onClick = onClick),
     ) {
@@ -626,14 +645,7 @@ private fun TimelineItem(
             over?.let {
                 TimeText(it, style = MaterialTheme.typography.bodyMedium, color = overColor ?: MaterialTheme.colorScheme.onSurfaceVariant, maxLines = 1)
             }
-            Text(
+            StrikeText(title, done = done, style = MaterialTheme.typography.titleMedium, maxLines = 2)
-                title,
-                style = MaterialTheme.typography.titleMedium,
-                maxLines = 2,
-                overflow = TextOverflow.Ellipsis,
-                textDecoration = if (done) TextDecoration.LineThrough else null,
-                color = if (done) MaterialTheme.colorScheme.onSurfaceVariant else MaterialTheme.colorScheme.onSurface,
-            )
             under?.let { Text(it, style = MaterialTheme.typography.bodySmall, color = MaterialTheme.colorScheme.onSurfaceVariant, maxLines = 1) }
         }
     }

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Common.kt

@@ -2,6 +2,8 @@
 
 package org.xtimms.psu.schedule.ui
 
+import androidx.compose.ui.platform.LocalHapticFeedback
+import androidx.compose.ui.hapticfeedback.HapticFeedbackType
 import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.staticCompositionLocalOf
 import androidx.compose.ui.platform.LocalConfiguration
@@ -21,6 +23,26 @@ import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.ColumnScope
 import androidx.compose.material3.HorizontalDivider
 import androidx.compose.ui.semantics.clearAndSetSemantics
+import androidx.compose.animation.core.Animatable
+import androidx.compose.animation.core.Spring
+import androidx.compose.animation.core.snap
+import androidx.compose.animation.core.spring
+import androidx.compose.animation.core.tween
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.draw.drawBehind
+import androidx.compose.ui.geometry.CornerRadius
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.geometry.Size
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.layout.onGloballyPositioned
+import androidx.compose.ui.layout.positionInRoot
+import java.time.temporal.ChronoUnit
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
 import androidx.compose.animation.animateColorAsState
 import androidx.compose.foundation.border
 import androidx.compose.ui.graphics.lerp
@@ -164,6 +186,7 @@ fun <T> ConnectedChoice(
     /** The check before the chosen label; times like "20:00" need the room, the fill marks it. */
     mark: Boolean = true,
 ) {
+    val haptic = LocalHapticFeedback.current
     Row(
         modifier.selectableGroup(),
         horizontalArrangement = Arrangement.spacedBy(ButtonGroupDefaults.ConnectedSpaceBetween),
@@ -172,7 +195,10 @@ fun <T> ConnectedChoice(
             val checked = value == selected
             ToggleButton(
                 checked = checked,
-                onCheckedChange = { onSelect(value) },
+                onCheckedChange = {
+                    if (!checked) haptic.performHapticFeedback(HapticFeedbackType.SegmentTick)
+                    onSelect(value)
+                },
                 modifier = Modifier.weight(1f).semantics { role = Role.RadioButton },
                 // Unselected segments need their own tonal fill to read as one group.
                 colors = ToggleButtonDefaults.colors(
@@ -357,6 +383,10 @@ fun weekTintOf(week: Week?): Color {
  * Seven days of a week in School Planner's calm style: the weekday, the date in a circle,
  * a filled circle for the selected day and primary text for today. Swiping between weeks
  * is the caller's pager; TalkBack gets the same moves as custom actions.
+ *
+ * The filled circle is one shape under the whole row: picking another day, it flows there on
+ * springs, its leading edge ahead of the trailing one. With [marks], a dot in a day's circle
+ * says it has lessons; the dots of a week pop in one day after another when it is picked.
  */
 @Composable
 fun DayStrip(
@@ -366,8 +396,38 @@ fun DayStrip(
     enabled: (LocalDate) -> Boolean = { true },
     onSelect: (LocalDate) -> Unit,
     onWeek: ((Int) -> Unit)? = null,
+    marks: Boolean = false,
     modifier: Modifier = Modifier,
 ) {
+    val haptic = LocalHapticFeedback.current
+    val scheme = MaterialTheme.colorScheme
+    val reduced = rememberReducedMotion()
+    val index = selected?.let { ChronoUnit.DAYS.between(monday, it).toInt() }?.takeIf { it in 0..6 }
+    // The indicator's edges, in days from Monday.
+    val left = remember { Animatable(index?.toFloat() ?: 0f) }
+    val right = remember { Animatable(index?.toFloat() ?: 0f) }
+    // False until the indicator stands in this week: a week just picked gets it in place, not sliding in.
+    var placed by remember { mutableStateOf(index != null) }
+    LaunchedEffect(index) {
+        if (index == null) {
+            placed = false
+            return@LaunchedEffect
+        }
+        val target = index.toFloat()
+        if (!placed || reduced) {
+            left.snapTo(target)
+            right.snapTo(target)
+            placed = true
+            return@LaunchedEffect
+        }
+        val forward = target > left.value
+        val lead = spring<Float>(dampingRatio = 0.8f, stiffness = Spring.StiffnessMedium)
+        val trail = spring<Float>(dampingRatio = 0.8f, stiffness = Spring.StiffnessMediumLow)
+        launch { (if (forward) right else left).animateTo(target, lead) }
+        (if (forward) left else right).animateTo(target, trail)
+    }
+    var rowTop by remember { mutableFloatStateOf(0f) }
+    var circleTop by remember { mutableFloatStateOf(-1f) }
     Row(
         modifier
             .fillMaxWidth()
@@ -380,14 +440,48 @@ fun DayStrip(
                         CustomAccessibilityAction("Следующая неделя") { onWeek(1); true },
                     )
                 },
-            ),
+            )
+            .onGloballyPositioned { rowTop = it.positionInRoot().y }
+            .drawBehind {
+                if (index == null || circleTop < 0f) return@drawBehind
+                val cell = size.width / 7
+                val d = 40.dp.toPx()
+                val from = if (placed) left.value else index.toFloat()
+                val to = if (placed) right.value else index.toFloat()
+                drawRoundRect(
+                    scheme.primary,
+                    topLeft = Offset(from * cell + (cell - d) / 2, circleTop - rowTop),
+                    size = Size((to - from) * cell + d, d),
+                    cornerRadius = CornerRadius(d / 2),
+                )
+            },
     ) {
         repeat(7) { i ->
             val date = monday.plusDays(i.toLong())
             val isSelected = date == selected
             val isToday = date == today()
             val busy = hasLessons(date)
-            val scheme = MaterialTheme.colorScheme
+            val ink by animateColorAsState(
+                when {
+                    isSelected -> scheme.onPrimary
+                    isToday -> scheme.primary
+                    busy -> scheme.onSurface
+                    else -> scheme.onSurfaceVariant
+                },
+                if (reduced) snap() else tween(200),
+                label = "day-ink",
+            )
+            // A week's dots wait until it is the one picked, then pop in from Monday on.
+            val dot = remember(monday) { Animatable(0f) }
+            val dotShown = marks && busy && (selected == null || index != null)
+            LaunchedEffect(monday, dotShown) {
+                if (!dotShown) dot.snapTo(0f)
+                else if (reduced || dot.value > 0f) dot.snapTo(1f)
+                else {
+                    delay(60L + 35L * i)
+                    dot.animateTo(1f, spring(dampingRatio = 0.5f, stiffness = Spring.StiffnessMedium))
+                }
+            }
             Column(
                 horizontalAlignment = Alignment.CenterHorizontally,
                 modifier = Modifier
@@ -399,7 +493,10 @@ fun DayStrip(
                         role = Role.Tab,
                         interactionSource = null,
                         indication = null,
-                        onClick = { onSelect(date) },
+                        onClick = {
+                            if (!isSelected) haptic.performHapticFeedback(HapticFeedbackType.SegmentTick)
+                            onSelect(date)
+                        },
                     )
                     .padding(vertical = 6.dp)
                     .semantics(mergeDescendants = true) {
@@ -417,17 +514,16 @@ fun DayStrip(
                     modifier = Modifier
                         .padding(top = 4.dp)
                         .size(40.dp)
-                        .background(if (isSelected) scheme.primary else Color.Transparent, CircleShape),
+                        .then(if (i == 0) Modifier.onGloballyPositioned { circleTop = it.positionInRoot().y } else Modifier),
                 ) {
-                    Text(
+                    Text("${date.dayOfMonth}", style = MaterialTheme.typography.titleMediumEmphasized, color = ink)
-                        "${date.dayOfMonth}",
+                    if (marks) Box(
-                        style = MaterialTheme.typography.titleMediumEmphasized,
+                        Modifier
-                        color = when {
+                            .align(Alignment.BottomCenter)
-                            isSelected -> scheme.onPrimary
+                            .padding(bottom = 4.dp)
-                            isToday -> scheme.primary
+                            .size(4.dp)
-                            busy -> scheme.onSurface
+                            .graphicsLayer { scaleX = dot.value; scaleY = dot.value }
-                            else -> scheme.onSurfaceVariant
+                            .background(ink, CircleShape),
-                        },
                     )
                 }
             }

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Done.kt

@@ -0,0 +1,119 @@
+package org.xtimms.psu.schedule.ui
+
+import androidx.compose.animation.animateColorAsState
+import androidx.compose.animation.core.Animatable
+import androidx.compose.animation.core.Spring
+import androidx.compose.animation.core.animateFloatAsState
+import androidx.compose.animation.core.snap
+import androidx.compose.animation.core.spring
+import androidx.compose.animation.core.tween
+import androidx.compose.foundation.Canvas
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.drawWithContent
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.graphics.Path
+import androidx.compose.ui.graphics.PathMeasure
+import androidx.compose.ui.graphics.StrokeCap
+import androidx.compose.ui.graphics.StrokeJoin
+import androidx.compose.ui.graphics.drawscope.Stroke
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.text.TextLayoutResult
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+
+// Finishing a task: its text is struck through from left to right, line after line, and once the
+// last open task of the plans is done a small check pops up by "Всё сделано".
+
+/** A task's text, struck through as it is done; the line draws itself instead of appearing. */
+@Composable
+fun StrikeText(text: String, done: Boolean, style: TextStyle, maxLines: Int, modifier: Modifier = Modifier) {
+    val reduced = rememberReducedMotion()
+    val strike by animateFloatAsState(if (done) 1f else 0f, if (reduced) snap() else tween(350, easing = EmphasizedDecelerate), label = "strike")
+    val color by animateColorAsState(
+        if (done) MaterialTheme.colorScheme.onSurfaceVariant else MaterialTheme.colorScheme.onSurface,
+        tween(350),
+        label = "done-color",
+    )
+    var layout by remember { mutableStateOf<TextLayoutResult?>(null) }
+    Text(
+        text,
+        style = style,
+        color = color,
+        maxLines = maxLines,
+        overflow = TextOverflow.Ellipsis,
+        onTextLayout = { layout = it },
+        modifier = modifier.drawWithContent {
+            drawContent()
+            val l = layout ?: return@drawWithContent
+            if (strike <= 0f) return@drawWithContent
+            // One run across all the lines: the first line is struck through, then the next.
+            val widths = (0 until l.lineCount).map { l.getLineRight(it) - l.getLineLeft(it) }
+            var left = widths.sum() * strike
+            for (i in 0 until l.lineCount) {
+                if (left <= 0f) break
+                val w = minOf(widths[i], left)
+                val y = (l.getLineTop(i) + l.getLineBottom(i)) / 2
+                drawLine(color, Offset(l.getLineLeft(i), y), Offset(l.getLineLeft(i) + w, y), strokeWidth = 1.5.dp.toPx())
+                left -= w
+            }
+        },
+    )
+}
+
+/** How long a ticked task stays in place, struck through, before it moves down to the done ones. */
+const val DONE_PAUSE = 420L
+
+/**
+ * A check in a circle that pops up (a springy scale, M3 Expressive) and draws its tick when
+ * [visible] turns true; already true when shown, it just sits there.
+ */
+@Composable
+fun DoneMark(visible: Boolean, modifier: Modifier = Modifier) {
+    val reduced = rememberReducedMotion()
+    val first = remember { visible }
+    val scale = remember { Animatable(if (first) 1f else 0f) }
+    val tick = remember { Animatable(if (first) 1f else 0f) }
+    LaunchedEffect(visible) {
+        if (!visible) {
+            scale.snapTo(0f)
+            tick.snapTo(0f)
+            return@LaunchedEffect
+        }
+        if (reduced) {
+            scale.snapTo(1f)
+            tick.snapTo(1f)
+            return@LaunchedEffect
+        }
+        launch { scale.animateTo(1f, spring(dampingRatio = 0.45f, stiffness = Spring.StiffnessMediumLow)) }
+        delay(120)
+        tick.animateTo(1f, tween(300, easing = EmphasizedDecelerate))
+    }
+    if (!visible && scale.value == 0f) return
+    val fill = MaterialTheme.colorScheme.primary
+    val ink = MaterialTheme.colorScheme.onPrimary
+    Canvas(modifier.padding(end = 6.dp).size(16.dp).graphicsLayer { scaleX = scale.value; scaleY = scale.value }) {
+        drawCircle(fill)
+        val path = Path().apply {
+            moveTo(size.width * 0.28f, size.height * 0.52f)
+            lineTo(size.width * 0.44f, size.height * 0.68f)
+            lineTo(size.width * 0.74f, size.height * 0.36f)
+        }
+        val measure = PathMeasure().apply { setPath(path, false) }
+        val drawn = Path()
+        measure.getSegment(0f, measure.length * tick.value, drawn, true)
+        drawPath(drawn, ink, style = Stroke(width = 2.dp.toPx(), cap = StrokeCap.Round, join = StrokeJoin.Round))
+    }
+}

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/GroupsScreen.kt

@@ -56,6 +56,7 @@ import org.xtimms.psu.schedule.data.GroupResult
 import org.xtimms.psu.schedule.data.attempt
 import org.xtimms.psu.schedule.data.GroupsResponse
 import org.xtimms.psu.schedule.data.SavedGroup
+import org.xtimms.psu.schedule.data.choiceKey
 
 private val PLAIN_PERIOD = Regex("^(осенний|весенний) семестр$|^расписание из word$", RegexOption.IGNORE_CASE)
 
@@ -97,15 +98,25 @@ fun GroupsScreen(
     }
     val searching = query.trim().length >= 2
 
-    // Before going back to the overview, a group with subgroups asks which one is yours,
+    // Before going back to the overview, a group with subgroups asks which one is yours, and a
-    // unless you already chose it for this group.
+    // group whose parts study German or French which you study, unless you chose it already.
     var askSubgroup by remember { mutableStateOf<List<String>?>(null) }
+    var askChoices by remember { mutableStateOf<List<List<String>>>(emptyList()) }
+    var askForeign by remember { mutableStateOf(false) }
+    // After the subgroup, the choices and then whether you are a foreign student; then the overview.
+    fun next() {
+        if (askSubgroup == null && askChoices.isEmpty() && !askForeign) onOpened()
+    }
     fun opened() {
         val t = vm.timetable.value
         val subgroups = t?.subgroups.orEmpty()
         val s = vm.settings.value
-        val chosen = s?.current?.group == t?.group && s?.subgroup != null
+        val same = s?.current?.group == t?.group
-        if (subgroups.isNotEmpty() && !chosen && !onboarding) askSubgroup = subgroups else onOpened()
+        if (onboarding) return onOpened()
+        askChoices = t?.choices.orEmpty().filterNot { same && s?.choices?.containsKey(choiceKey(it)) == true }
+        askForeign = t?.audience == true && !(same && s?.foreign != null)
+        if (subgroups.isNotEmpty() && !(same && s?.subgroup != null)) askSubgroup = subgroups
+        next()
     }
 
     fun open(result: GroupResult) {
@@ -169,6 +180,12 @@ fun GroupsScreen(
                         subgroups = timetable?.subgroups.orEmpty(),
                         subgroup = settings?.subgroup,
                         onSubgroup = vm::setSubgroup,
+                        choices = timetable?.choices.orEmpty(),
+                        taken = settings?.choices.orEmpty(),
+                        onChoice = vm::setChoice,
+                        audience = timetable?.audience == true,
+                        foreign = settings?.foreign,
+                        onForeign = vm::setForeign,
                     )
                 }
                 val recent = settings?.recent.orEmpty().filterNot { it.docId == current?.docId && it.group == current?.group }
@@ -233,9 +250,7 @@ fun GroupsScreen(
                         }
                     }
                 }
-                if (data == null && error == null) item {
+                if (data == null && error == null) item { RowsSkeleton() }
-                    Row(Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.Center) { LoadingIndicator() }
-                }
             }
         }
         }
@@ -244,7 +259,32 @@ fun GroupsScreen(
         SubgroupDialog(
             group = vm.timetable.value?.group.orEmpty(),
             subgroups = subgroups,
-            onPick = { vm.setSubgroup(it); askSubgroup = null; onOpened() },
+            onPick = {
+                vm.setSubgroup(it)
+                askSubgroup = null
+                next()
+            },
+        )
+    }
+    if (askSubgroup == null) askChoices.firstOrNull()?.let { options ->
+        ChoiceDialog(
+            group = vm.timetable.value?.group.orEmpty(),
+            options = options,
+            onPick = {
+                vm.setChoice(options, it)
+                askChoices = askChoices.drop(1)
+                next()
+            },
+        )
+    }
+    if (askSubgroup == null && askChoices.isEmpty() && askForeign) {
+        ForeignDialog(
+            group = vm.timetable.value?.group.orEmpty(),
+            onPick = {
+                vm.setForeign(it)
+                askForeign = false
+                next()
+            },
         )
     }
 }
@@ -270,7 +310,18 @@ private fun GroupRows(results: List<GroupResult>, opening: String?, onOpen: (Gro
 }
 
 @Composable
-private fun CurrentGroup(current: SavedGroup, subgroups: List<String>, subgroup: String?, onSubgroup: (String?) -> Unit) {
+private fun CurrentGroup(
+    current: SavedGroup,
+    subgroups: List<String>,
+    subgroup: String?,
+    onSubgroup: (String?) -> Unit,
+    choices: List<List<String>>,
+    taken: Map<String, String>,
+    onChoice: (List<String>, String?) -> Unit,
+    audience: Boolean,
+    foreign: Boolean?,
+    onForeign: (Boolean?) -> Unit,
+) {
     ListCard(Icons.Rounded.CheckCircle, "Сейчас открыта") {
         CardRow(
             avatar = avatarLabel(current.group),
@@ -291,9 +342,113 @@ private fun CurrentGroup(current: SavedGroup, subgroups: List<String>, subgroup:
                 modifier = Modifier.fillMaxWidth(),
             )
         }
+        // Long names ("Стилистика русского языка. Культура речи") wrap as chips instead of a button row.
+        choices.forEach { options ->
+            val mine = taken[choiceKey(options)]
+            Column(
+                verticalArrangement = Arrangement.spacedBy(4.dp),
+                modifier = Modifier.padding(start = 20.dp, end = 20.dp, bottom = 12.dp),
+            ) {
+                Text("Что вы изучаете", style = MaterialTheme.typography.labelLarge, color = MaterialTheme.colorScheme.onSurfaceVariant)
+                FlowRow(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                    (listOf<String?>(null) + options).forEach { option ->
+                        val on = mine == option
+                        FilterChip(
+                            selected = on,
+                            onClick = { onChoice(options, option) },
+                            label = { Text(option ?: "Всё") },
+                            leadingIcon = if (on) ({ Icon(Icons.Rounded.Check, null, Modifier.size(FilterChipDefaults.IconSize)) }) else null,
+                        )
+                    }
+                }
+            }
+        }
+        if (audience) Column(
+            verticalArrangement = Arrangement.spacedBy(8.dp),
+            modifier = Modifier.padding(start = 20.dp, end = 20.dp, bottom = 12.dp),
+        ) {
+            Text("Иностранный студент", style = MaterialTheme.typography.labelLarge, color = MaterialTheme.colorScheme.onSurfaceVariant)
+            ConnectedChoice(
+                options = listOf<Pair<Boolean?, String>>(null to "Всё", true to "Да", false to "Нет"),
+                selected = foreign,
+                onSelect = onForeign,
+                modifier = Modifier.fillMaxWidth(),
+            )
+        }
     }
 }
 
+internal fun foreignText(group: String): String =
+    "В группе $group часть пар только для иностранных студентов («Русский язык как иностранный»), а часть — только для остальных. " +
+        "Ответьте, и чужие пары скроются из расписания, виджета и напоминаний. Изменить можно в разделе «Группы»."
+
+/** "Вы иностранный студент?": the answer is remembered for this group. */
+@Composable
+private fun ForeignDialog(group: String, onPick: (Boolean?) -> Unit) {
+    AlertDialog(
+        onDismissRequest = { onPick(null) },
+        icon = { Icon(Icons.Rounded.Groups, contentDescription = null) },
+        title = { Text("Вы иностранный студент?") },
+        text = {
+            Column(verticalArrangement = Arrangement.spacedBy(4.dp)) {
+                Text(foreignText(group), style = MaterialTheme.typography.bodyMedium)
+                Spacer(Modifier.height(8.dp))
+                listOf<Pair<Boolean?, String>>(true to "Да, иностранный", false to "Нет", null to "Показывать всё").forEach { (value, label) ->
+                    Surface(
+                        onClick = { onPick(value) },
+                        shape = MaterialTheme.shapes.large,
+                        color = MaterialTheme.colorScheme.secondaryContainer,
+                        contentColor = MaterialTheme.colorScheme.onSecondaryContainer,
+                        modifier = Modifier.fillMaxWidth(),
+                    ) {
+                        Text(label, style = MaterialTheme.typography.titleSmallEmphasized, modifier = Modifier.padding(horizontal = 16.dp, vertical = 14.dp))
+                    }
+                }
+            }
+        },
+        confirmButton = {},
+        dismissButton = { TextButton(onClick = { onPick(null) }) { Text("Позже") } },
+    )
+}
+
+/** What a part of the group takes, in a sentence: "«Немецкий язык» или «Французский язык»". */
+internal fun choiceText(group: String, options: List<String>): String =
+    "В группе $group часть пар идёт на выбор: ${options.joinToString(" или ") { "«$it»" }}. Выберите, что изучаете вы, — " +
+        "пары другого варианта скроются из расписания, виджета и напоминаний. Изменить можно в разделе «Группы»."
+
+/** "Что вы изучаете": German or French, say; the choice is remembered for this group. */
+@Composable
+private fun ChoiceDialog(group: String, options: List<String>, onPick: (String?) -> Unit) {
+    AlertDialog(
+        onDismissRequest = { onPick(null) },
+        icon = { Icon(Icons.Rounded.Groups, contentDescription = null) },
+        title = { Text("Что вы изучаете?") },
+        text = {
+            Column(verticalArrangement = Arrangement.spacedBy(4.dp)) {
+                Text(choiceText(group, options), style = MaterialTheme.typography.bodyMedium)
+                Spacer(Modifier.height(8.dp))
+                (options + listOf<String?>(null)).forEach { option ->
+                    Surface(
+                        onClick = { onPick(option) },
+                        shape = MaterialTheme.shapes.large,
+                        color = MaterialTheme.colorScheme.secondaryContainer,
+                        contentColor = MaterialTheme.colorScheme.onSecondaryContainer,
+                        modifier = Modifier.fillMaxWidth(),
+                    ) {
+                        Text(
+                            option ?: "Показывать всё",
+                            style = MaterialTheme.typography.titleSmallEmphasized,
+                            modifier = Modifier.padding(horizontal = 16.dp, vertical = 14.dp),
+                        )
+                    }
+                }
+            }
+        },
+        confirmButton = {},
+        dismissButton = { TextButton(onClick = { onPick(null) }) { Text("Позже") } },
+    )
+}
+
 /** "Ваша подгруппа": all of them, or one; the choice is remembered for this group. */
 @Composable
 private fun SubgroupDialog(group: String, subgroups: List<String>, onPick: (String?) -> Unit) {

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/HomeScreen.kt

@@ -62,7 +62,6 @@ import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.ExperimentalMaterial3ExpressiveApi
 import androidx.compose.material3.HorizontalDivider
 import androidx.compose.material3.Icon
-import androidx.compose.material3.LoadingIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.ModalBottomSheet
 import androidx.compose.material3.Surface
@@ -127,10 +126,11 @@ fun rememberClock(): LocalTime {
 
 @Composable
 fun HomeScreen(vm: MainViewModel, nav: AppNav) {
+    val undo = LocalUndo.current
     val timetable by vm.timetable.collectAsStateWithLifecycle()
     val settings by vm.settings.collectAsStateWithLifecycle()
     val status by vm.status.collectAsStateWithLifecycle()
-    var details by remember { mutableStateOf<Pair<Lesson, LocalDate>?>(null) }
+    val openLesson = rememberLessonOpener(vm)
     var editing by remember { mutableStateOf<Note?>(null) }
     var session by remember { mutableStateOf(false) }
     val changes by vm.changes.collectAsStateWithLifecycle()
@@ -180,7 +180,7 @@ fun HomeScreen(vm: MainViewModel, nav: AppNav) {
         status.message?.let { Banner(it, offline = status.offline, onClose = vm::dismissMessage, onRetry = if (status.offline) vm::retry else null, action = if (status.needsGroup) "Выбрать группу" to nav.openGroups else null) }
         val t = timetable
         when {
-            t == null && status.loading -> Box(Modifier.fillMaxSize(), contentAlignment = Alignment.Center) { LoadingIndicator() }
+            t == null && status.loading -> OverviewSkeleton()
             t == null -> CenteredEmpty {
                 Empty(
                     "Расписание не загружено",
@@ -196,8 +196,10 @@ fun HomeScreen(vm: MainViewModel, nav: AppNav) {
                     Empty("Обзор недоступен", "Строки Word по дням недели — во вкладке «Расписание».", icon = Icons.Rounded.Description, action = "Открыть" to { nav.openDay(date) })
                 }
             }
-            else -> BoxWithConstraints(Modifier.fillMaxSize()) {
+            // Pull down for the latest timetable, as on the schedule.
+            else -> ExpressiveRefresh(refreshing = status.loading, onRefresh = { vm.refresh() }) { BoxWithConstraints(Modifier.fillMaxSize()) {
                 val twoPane = twoPane(maxWidth)
+                val intro = remember { vm.takeIntro() }
                 val overview: @Composable (Modifier) -> Unit = { listModifier ->
                 val todaySlots = vm.slotsOn(t, date, subgroup)
                 val next = (1..7).asSequence()
@@ -225,10 +227,10 @@ fun HomeScreen(vm: MainViewModel, nav: AppNav) {
                             }
                         }
                     }
-                    item(key = "week") { AnimatedItem { WeekReport(vm, t, subgroup, date, clock) } }
+                    item(key = "week") { AnimatedItem { Entrance(0, intro) { WeekReport(vm, t, subgroup, date, clock) } } }
-                    item(key = "session") { AnimatedItem { SessionCard(vm, t, onOpen = { session = true }) } }
+                    item(key = "session") { AnimatedItem { Entrance(1, intro) { SessionCard(vm, t, onOpen = { session = true }) } } }
-                    item(key = "today-title") { AnimatedItem { DayTitle("Сегодня", date) } }
+                    item(key = "today-title") { AnimatedItem { Entrance(2, intro) { DayTitle("Сегодня", date) } } }
-                    item(key = "today") { AnimatedItem { TodayCard(todaySlots, vm.placesOn(t, date, subgroup), clock, onOpen = { details = it to date }, onDay = { nav.openDay(date) }) } }
+                    item(key = "today") { AnimatedItem { Entrance(3, intro) { TodayCard(todaySlots, vm.placesOn(t, date, subgroup), clock, onOpen = { openLesson(it, date) }, onDay = { nav.openDay(date) }) } } }
                     item(key = "attendance") { AnimatedItem { AttendanceCard(vm, todaySlots) } }
                     item(key = "tasks") { AnimatedItem { TasksCard(vm, onEdit = { editing = it }, onAll = nav.openPlans) } }
                     if (next != null) {
@@ -237,7 +239,7 @@ fun HomeScreen(vm: MainViewModel, nav: AppNav) {
                         item(key = "next") {
                             SectionCard(Icons.Rounded.EventAvailable, plural(slots.size, "пара", "пары", "пар").let { "${slots.size} $it" }) {
                                 DayPlaces(vm.placesOn(t, day, subgroup))
-                                slots.forEach { slot -> slot.lessons.forEach { CompactLesson(it, slot, onClick = { details = it to day }) } }
+                                slots.forEach { slot -> slot.lessons.forEach { CompactLesson(it, slot, onClick = { openLesson(it, day) }) } }
                                 DayButton { nav.openDay(day) }
                             }
                         }
@@ -248,10 +250,10 @@ fun HomeScreen(vm: MainViewModel, nav: AppNav) {
                 // a foldable half opened like a book puts one on each side of the fold.
                 if (twoPane) PaneRow(Modifier.fillMaxSize().padding(end = 16.dp), firstWidth = 440.dp, gap = 0.dp, first = { overview(it) }) {
                     DetailPane(it) {
-                        WeekPane(vm, t, subgroup, onOpen = { lesson, day -> details = lesson to day })
+                        WeekPane(vm, t, subgroup, onOpen = { lesson, day -> openLesson(lesson, day) })
                     }
                 } else ContentColumn { overview(Modifier.fillMaxSize()) }
-            }
+            } }
         }
     }
     if (changesOpen) changes?.let { record ->
@@ -267,13 +269,10 @@ fun HomeScreen(vm: MainViewModel, nav: AppNav) {
             editing = note,
             groupKey = note.group,
             onSave = { vm.saveNote(it); editing = null },
-            onDelete = { vm.deleteNote(it.id); editing = null },
+            onDelete = { vm.deleteNote(it.id, undo); editing = null },
             onDismiss = { editing = null },
         )
     }
-    details?.let { lesson ->
-        ModalBottomSheet(onDismissRequest = { details = null }) { LessonDetails(lesson.first, timetable?.bells.orEmpty(), lesson.second, vm, onClose = { details = null }) }
-    }
 }
 
 /** Shortcuts under the app bar, as in School Planner's overview. */
@@ -520,6 +519,7 @@ private fun FeaturedLesson(lesson: Lesson, slot: Slot, clock: LocalTime, onClick
     Row(
         Modifier
             .fillMaxWidth()
+            .morphOrigin("featured|${slot.date}|${lesson.key}|${lesson.start}", MaterialTheme.colorScheme.card, 12.dp)
             .clip(MaterialTheme.shapes.medium)
             .clickable(onClickLabel = "Подробнее", role = Role.Button, onClick = onClick),
     ) {
@@ -537,7 +537,7 @@ private fun FeaturedLesson(lesson: Lesson, slot: Slot, clock: LocalTime, onClick
                     color = if (running) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.secondaryContainer,
                     contentColor = if (running) MaterialTheme.colorScheme.onPrimary else MaterialTheme.colorScheme.onSecondaryContainer,
                 ) {
-                    Text(
+                    RollingText(
                         if (running) "Идёт · ещё ${minutesLabel(minutes)}" else "Через ${minutesLabel(minutes)}",
                         style = MaterialTheme.typography.labelLarge,
                         modifier = Modifier.padding(horizontal = 10.dp, vertical = 4.dp),
@@ -560,7 +560,10 @@ fun CompactLesson(lesson: Lesson, slot: Slot, onClick: (() -> Unit)?) {
         Modifier
             .fillMaxWidth()
             .then(
-                if (onClick != null) Modifier.clip(MaterialTheme.shapes.medium).clickable(onClickLabel = "Подробнее", role = Role.Button, onClick = onClick)
+                if (onClick != null) Modifier
+                    .morphOrigin("compact|${slot.date}|${lesson.key}|${lesson.start}", MaterialTheme.colorScheme.card, 12.dp)
+                    .clip(MaterialTheme.shapes.medium)
+                    .clickable(onClickLabel = "Подробнее", role = Role.Button, onClick = onClick)
                 else Modifier,
             ),
         verticalAlignment = Alignment.CenterVertically,

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/MainViewModel.kt

@@ -74,7 +74,19 @@ class MainViewModel(application: Application) : AndroidViewModel(application) {
     }
 
     fun saveNote(note: Note) = viewModelScope.launch { app.notes.save(note) }
-    fun deleteNote(id: String) = viewModelScope.launch { app.notes.delete(id) }
+    /** Deletes at once and offers it back in [undo]; the photos go only when the offer is gone. */
+    fun deleteNote(id: String, undo: UndoHost? = null) = viewModelScope.launch {
+        val note = app.notes.remove(id) ?: return@launch
+        if (undo == null) {
+            app.notes.discard(note.photos)
+            return@launch
+        }
+        undo.offer(
+            if (note.task) "Задание удалено" else "Заметка удалена",
+            onUndo = { viewModelScope.launch { app.notes.save(note) } },
+            onGone = { app.notes.discard(note.photos) },
+        )
+    }
     fun toggleNote(id: String) = viewModelScope.launch { app.notes.toggle(id) }
 
     /** The key new notes are filed under, or null before a group is chosen. */
@@ -148,6 +160,16 @@ class MainViewModel(application: Application) : AndroidViewModel(application) {
         SyncWorker.afterChange(getApplication())
     }
 
+    fun setChoice(options: List<String>, option: String?) = viewModelScope.launch {
+        app.settings.setChoice(options, option)
+        SyncWorker.afterChange(getApplication())
+    }
+
+    fun setForeign(foreign: Boolean?) = viewModelScope.launch {
+        app.settings.setForeign(foreign)
+        SyncWorker.afterChange(getApplication())
+    }
+
     fun setTheme(mode: ThemeMode) = viewModelScope.launch { app.settings.setTheme(mode) }
     fun setDynamicColor(on: Boolean) = viewModelScope.launch { app.settings.setDynamicColor(on) }
     fun setDisplay(display: Display) = viewModelScope.launch { app.settings.setDisplay(display) }
@@ -166,6 +188,14 @@ class MainViewModel(application: Application) : AndroidViewModel(application) {
 
     fun setChangeAlerts(on: Boolean) = viewModelScope.launch { app.settings.setChangeAlerts(on) }
 
+    /** The overview's cards rise in once per launch, after the launch screen, not on every return. */
+    private var introShown = false
+    fun takeIntro(): Boolean = !introShown.also { introShown = true }
+
+    /** Lessons a republished document just added or changed; each card glows once. */
+    val fresh: StateFlow<Set<String>> = app.repository.fresh
+    fun freshShown(key: String) = app.repository.freshShown(key)
+
     /** "Новое задание" from the launcher: the plans open with the add sheet. */
     val newTask = kotlinx.coroutines.flow.MutableStateFlow(false)
 

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Morph.kt

@@ -0,0 +1,261 @@
+package org.xtimms.psu.schedule.ui
+
+import androidx.activity.compose.PredictiveBackHandler
+import androidx.compose.animation.core.Animatable
+import androidx.compose.animation.core.tween
+import androidx.compose.foundation.background
+import androidx.compose.foundation.gestures.awaitEachGesture
+import androidx.compose.foundation.gestures.awaitFirstDown
+import androidx.compose.foundation.gestures.detectTapGestures
+import androidx.compose.foundation.gestures.detectVerticalDragGestures
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.BoxWithConstraints
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.offset
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.Stable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.setValue
+import androidx.compose.runtime.staticCompositionLocalOf
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.draw.drawBehind
+import androidx.compose.ui.draw.drawWithContent
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.geometry.Rect
+import androidx.compose.ui.geometry.lerp
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.graphics.layer.GraphicsLayer
+import androidx.compose.ui.graphics.layer.drawLayer
+import androidx.compose.ui.graphics.lerp
+import androidx.compose.ui.graphics.rememberGraphicsLayer
+import androidx.compose.ui.graphics.drawscope.scale
+import androidx.compose.ui.input.pointer.PointerEventPass
+import androidx.compose.ui.input.pointer.pointerInput
+import androidx.compose.ui.layout.Layout
+import androidx.compose.ui.layout.boundsInRoot
+import androidx.compose.ui.layout.onGloballyPositioned
+import androidx.compose.ui.layout.positionInRoot
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.unit.Constraints
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.IntOffset
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.lerp
+import kotlinx.coroutines.CancellationException
+import kotlinx.coroutines.launch
+import kotlin.math.roundToInt
+
+// The M3 container transform: a card grows into its details, the "+" button into the sheet of a
+// new plan, and back. Bottom sheets live in windows of their own and cannot grow from a card, so
+// these open in one overlay over the app (MorphOverlay) instead.
+
+/** Where a transform starts: an element's bounds, its fill and corners and a picture of it. */
+class MorphOrigin(val bounds: Rect, val color: Color, val radius: Dp, val picture: GraphicsLayer)
+
+enum class MorphKind {
+    /** A page: the whole screen on a phone, a large panel on a tablet. */
+    Page,
+
+    /** A sheet from the bottom, with a handle to drag it away. */
+    Sheet,
+}
+
+class MorphEntry(val key: String?, val kind: MorphKind, val content: @Composable (close: () -> Unit) -> Unit)
+
+@Stable
+class MorphHost {
+    internal val origins = mutableMapOf<String, MorphOrigin>()
+    // The element the finger went down on, and when: the page grows from what was tapped.
+    internal var touched: String? = null
+    internal var touchedAt = 0L
+    var entry by mutableStateOf<MorphEntry?>(null)
+        internal set
+    internal var closing by mutableStateOf(false)
+    internal val progress = Animatable(0f)
+
+    /** Opens [content] growing out of the element tapped a moment ago, if any. */
+    fun open(kind: MorphKind, content: @Composable (close: () -> Unit) -> Unit) {
+        val key = touched?.takeIf { System.currentTimeMillis() - touchedAt < 1500 }
+        closing = false
+        entry = MorphEntry(key, kind, content)
+    }
+
+    fun close() {
+        if (entry != null) closing = true
+    }
+}
+
+val LocalMorph = staticCompositionLocalOf<MorphHost?> { null }
+
+/**
+ * Marks a card or a button as a place a page or a sheet grows from. While its page is open the
+ * element itself is hidden: the page has taken its place.
+ */
+@Composable
+fun Modifier.morphOrigin(key: String, color: Color, radius: Dp): Modifier {
+    val host = LocalMorph.current ?: return this
+    val picture = rememberGraphicsLayer()
+    DisposableEffect(host, key) { onDispose { host.origins.remove(key) } }
+    val hidden = host.entry?.key == key
+    return this
+        .onGloballyPositioned { host.origins[key] = MorphOrigin(it.boundsInRoot(), color, radius, picture) }
+        .pointerInput(host, key) {
+            awaitEachGesture {
+                awaitFirstDown(requireUnconsumed = false, pass = PointerEventPass.Initial)
+                host.touched = key
+                host.touchedAt = System.currentTimeMillis()
+            }
+        }
+        .drawWithContent {
+            picture.record { this@drawWithContent.drawContent() }
+            if (!hidden) drawLayer(picture)
+        }
+}
+
+/**
+ * The open page or sheet over the app. Opening, it grows from its origin (or from the middle):
+ * the origin's picture fades out over the first third, the content fades in after it. Back,
+ * a tap on the scrim or the predictive back gesture shrink it back the same way.
+ */
+@Composable
+fun MorphOverlay(host: MorphHost) {
+    val entry = host.entry ?: return
+    val reduced = rememberReducedMotion()
+    val scope = rememberCoroutineScope()
+    var back by remember { mutableFloatStateOf(0f) }
+    var drag by remember { mutableFloatStateOf(0f) }
+    var rootOffset by remember { mutableStateOf(Offset.Zero) }
+    LaunchedEffect(entry) {
+        back = 0f
+        drag = 0f
+        host.progress.snapTo(0f)
+        host.progress.animateTo(1f, tween(if (reduced) 0 else 450, easing = Emphasized))
+    }
+    LaunchedEffect(host.closing) {
+        if (!host.closing) return@LaunchedEffect
+        host.progress.animateTo(0f, tween(if (reduced) 0 else 350, easing = Emphasized))
+        host.entry = null
+        host.closing = false
+    }
+    PredictiveBackHandler(enabled = !host.closing) { events ->
+        try {
+            events.collect { back = it.progress }
+            host.close()
+        } catch (e: CancellationException) {
+            scope.launch { back = 0f }
+            throw e
+        }
+    }
+
+    val density = LocalDensity.current
+    val surface = MaterialTheme.colorScheme.surfaceContainerLow
+    BoxWithConstraints(Modifier.fillMaxSize().onGloballyPositioned { rootOffset = it.positionInRoot() }) {
+        val w = constraints.maxWidth.toFloat()
+        val h = constraints.maxHeight.toFloat()
+        val wide = maxWidth >= 600.dp
+        val margin = with(density) { 24.dp.toPx() }
+        val target = when (entry.kind) {
+            MorphKind.Page -> if (wide) {
+                val pw = minOf(w - 2 * margin, with(density) { 680.dp.toPx() })
+                Rect(Offset((w - pw) / 2, margin), androidx.compose.ui.geometry.Size(pw, h - 2 * margin))
+            } else Rect(0f, 0f, w, h)
+            MorphKind.Sheet -> {
+                val sw = minOf(w, with(density) { 640.dp.toPx() })
+                val sh = h * 0.82f
+                Rect(Offset((w - sw) / 2, h - sh), androidx.compose.ui.geometry.Size(sw, sh))
+            }
+        }
+        val origin = entry.key?.let { host.origins[it] }
+        val from = origin?.bounds?.translate(-rootOffset) ?: Rect(target.center, 0f).inflate(minOf(target.width, target.height) * 0.3f)
+        val p = host.progress.value
+        val rect = lerp(from, target, p)
+        val targetRadius = when {
+            entry.kind == MorphKind.Sheet -> 28.dp
+            wide -> 28.dp
+            else -> 0.dp
+        }
+        val radius = lerp(origin?.radius ?: 28.dp, targetRadius, p)
+        val shape = if (entry.kind == MorphKind.Sheet) RoundedCornerShape(radius, radius, lerp(origin?.radius ?: 28.dp, 0.dp, p), lerp(origin?.radius ?: 28.dp, 0.dp, p))
+        else RoundedCornerShape(radius)
+        // The scrim; a tap on it closes.
+        Box(
+            Modifier
+                .fillMaxSize()
+                .background(Color.Black.copy(alpha = 0.32f * p))
+                .pointerInput(host) { detectTapGestures { host.close() } },
+        )
+        Layout(
+            content = {
+                // The content, laid out once at its final size, revealed by the growing bounds.
+                Box(Modifier.graphicsLayer { alpha = ((p - 0.3f) / 0.7f).coerceIn(0f, 1f) }) {
+                    if (entry.kind == MorphKind.Sheet) SheetChrome(onDrag = { drag = (drag + it).coerceAtLeast(0f) }, onRelease = {
+                        if (drag > with(density) { 120.dp.toPx() }) host.close() else drag = 0f
+                    }) { entry.content(host::close) }
+                    else entry.content(host::close)
+                }
+                // The origin's own picture, fading out as the page takes over.
+                if (origin != null) Box(
+                    Modifier
+                        .graphicsLayer { alpha = (1f - p / 0.3f).coerceIn(0f, 1f) }
+                        .drawBehind {
+                            val s = rect.width / origin.bounds.width.coerceAtLeast(1f)
+                            scale(s, s, pivot = Offset.Zero) { drawLayer(origin.picture) }
+                        },
+                )
+            },
+            modifier = Modifier
+                .offset { IntOffset(rect.left.roundToInt(), rect.top.roundToInt()) }
+                .graphicsLayer {
+                    val s = 1f - 0.08f * back
+                    scaleX = s
+                    scaleY = s
+                    translationY = drag
+                }
+                .clip(shape)
+                .background(lerp(origin?.color ?: surface, surface, (p / 0.5f).coerceIn(0f, 1f)))
+                // Taps inside the page never reach the scrim under it.
+                .pointerInput(Unit) { detectTapGestures { } },
+        ) { measurables, _ ->
+            val content = measurables[0].measure(Constraints.fixed(target.width.roundToInt(), target.height.roundToInt()))
+            val picture = measurables.getOrNull(1)?.measure(Constraints.fixed(rect.width.roundToInt().coerceAtLeast(0), rect.height.roundToInt().coerceAtLeast(0)))
+            layout(rect.width.roundToInt().coerceAtLeast(0), rect.height.roundToInt().coerceAtLeast(0)) {
+                content.place((target.left - rect.left).roundToInt(), (target.top - rect.top).roundToInt())
+                picture?.place(0, 0)
+            }
+        }
+    }
+}
+
+/** A sheet's handle, which drags the sheet down and away. */
+@Composable
+private fun SheetChrome(onDrag: (Float) -> Unit, onRelease: () -> Unit, content: @Composable () -> Unit) {
+    Column(Modifier.fillMaxSize()) {
+        Box(
+            Modifier
+                .fillMaxWidth()
+                .height(36.dp)
+                .pointerInput(Unit) { detectVerticalDragGestures(onDragEnd = onRelease, onDragCancel = onRelease) { _, dy -> onDrag(dy) } },
+            contentAlignment = Alignment.Center,
+        ) {
+            Surface(shape = RoundedCornerShape(2.dp), color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.4f), modifier = Modifier.size(32.dp, 4.dp)) {}
+        }
+        Box(Modifier.weight(1f)) { content() }
+    }
+}

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Motion.kt

@@ -28,6 +28,8 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.remember
 import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.unit.dp
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.draw.drawWithContent
 
 // Material motion patterns, as in RideBus: shared axis X between a screen and the page it
 // opens, fade through between top-level destinations.
@@ -103,3 +105,130 @@ fun LazyStaggeredGridItemScope.AnimatedItem(content: @Composable () -> Unit) {
 fun materialFadeThrough(): ContentTransform =
     (fadeIn(tween(400, easing = EmphasizedDecelerate)) + scaleIn(tween(400, easing = EmphasizedDecelerate), initialScale = 0.92f)) togetherWith
         fadeOut(tween(200, easing = EmphasizedAccelerate))
+
+/**
+ * Whether the student turned animations off ("Убрать анимацию" sets the animator scale to 0):
+ * decorative motion is skipped then.
+ */
+@Composable
+fun rememberReducedMotion(): Boolean {
+    val resolver = androidx.compose.ui.platform.LocalContext.current.contentResolver
+    return remember {
+        android.provider.Settings.Global.getFloat(resolver, android.provider.Settings.Global.ANIMATOR_DURATION_SCALE, 1f) == 0f
+    }
+}
+
+/**
+ * The overview's cards after the launch screen: each rises 24dp and fades in, a little after
+ * the one above it. Only on [play] (the first overview of a launch), never with reduced motion.
+ */
+@Composable
+fun Entrance(index: Int, play: Boolean, content: @Composable () -> Unit) {
+    val reduced = rememberReducedMotion()
+    if (!play || reduced) {
+        content()
+        return
+    }
+    val shown = remember { androidx.compose.animation.core.Animatable(0f) }
+    androidx.compose.runtime.LaunchedEffect(Unit) {
+        kotlinx.coroutines.delay(60L * index)
+        shown.animateTo(1f, tween(MotionDuration.Medium4, easing = EmphasizedDecelerate))
+    }
+    Box(
+        Modifier.graphicsLayer {
+            alpha = shown.value
+            translationY = (1f - shown.value) * 24.dp.toPx()
+        },
+    ) { content() }
+}
+
+/**
+ * A short changing label ("ещё 25 мин" → "ещё 24 мин") that rolls up to its new value instead
+ * of flicking; still with animations turned off.
+ */
+@Composable
+fun RollingText(text: String, style: androidx.compose.ui.text.TextStyle, modifier: Modifier = Modifier) {
+    if (rememberReducedMotion()) {
+        androidx.compose.material3.Text(text, style = style, modifier = modifier)
+        return
+    }
+    androidx.compose.animation.AnimatedContent(
+        targetState = text,
+        transitionSpec = {
+            (androidx.compose.animation.slideInVertically(tween(MotionDuration.Short4, easing = EmphasizedDecelerate)) { it } + fadeIn(tween(MotionDuration.Short4))) togetherWith
+                (androidx.compose.animation.slideOutVertically(tween(MotionDuration.Short4, easing = EmphasizedAccelerate)) { -it } + fadeOut(tween(MotionDuration.Short4))) using
+                androidx.compose.animation.SizeTransform(clip = true)
+        },
+        label = "rolling",
+        modifier = modifier,
+    ) { androidx.compose.material3.Text(it, style = style) }
+}
+
+/**
+ * The lesson under way: a line runs around the card's edge as the pair goes, from its top-left
+ * corner clockwise, over a faint full outline. [progress] is 0..1.
+ */
+fun Modifier.progressBorder(progress: Float, color: androidx.compose.ui.graphics.Color, radius: androidx.compose.ui.unit.Dp): Modifier =
+    drawWithContent {
+        drawContent()
+        val stroke = 3.dp.toPx()
+        val inset = stroke / 2
+        val r = radius.toPx() - inset
+        // Round the card clockwise from just after its top-left corner, so the line starts there.
+        val l = inset
+        val t = inset
+        val rr = size.width - inset
+        val b = size.height - inset
+        val path = androidx.compose.ui.graphics.Path().apply {
+            moveTo(l + r, t)
+            lineTo(rr - r, t)
+            arcTo(androidx.compose.ui.geometry.Rect(rr - 2 * r, t, rr, t + 2 * r), -90f, 90f, false)
+            lineTo(rr, b - r)
+            arcTo(androidx.compose.ui.geometry.Rect(rr - 2 * r, b - 2 * r, rr, b), 0f, 90f, false)
+            lineTo(l + r, b)
+            arcTo(androidx.compose.ui.geometry.Rect(l, b - 2 * r, l + 2 * r, b), 90f, 90f, false)
+            lineTo(l, t + r)
+            arcTo(androidx.compose.ui.geometry.Rect(l, t, l + 2 * r, t + 2 * r), 180f, 90f, false)
+            close()
+        }
+        drawPath(path, color.copy(alpha = 0.22f), style = androidx.compose.ui.graphics.drawscope.Stroke(width = 2.dp.toPx()))
+        val measure = androidx.compose.ui.graphics.PathMeasure().apply { setPath(path, false) }
+        val done = androidx.compose.ui.graphics.Path()
+        measure.getSegment(0f, measure.length * progress.coerceIn(0f, 1f), done, true)
+        drawPath(done, color, style = androidx.compose.ui.graphics.drawscope.Stroke(width = stroke, cap = androidx.compose.ui.graphics.StrokeCap.Round))
+    }
+
+/**
+ * Pull to refresh with the M3 Expressive loading indicator, its shape morphing while the
+ * timetable loads; a tick under the finger when the pull is far enough to refresh.
+ */
+@OptIn(androidx.compose.material3.ExperimentalMaterial3Api::class, androidx.compose.material3.ExperimentalMaterial3ExpressiveApi::class)
+@Composable
+fun ExpressiveRefresh(
+    refreshing: Boolean,
+    onRefresh: () -> Unit,
+    modifier: Modifier = Modifier,
+    content: @Composable androidx.compose.foundation.layout.BoxScope.() -> Unit,
+) {
+    val state = androidx.compose.material3.pulltorefresh.rememberPullToRefreshState()
+    val haptic = androidx.compose.ui.platform.LocalHapticFeedback.current
+    val busy = androidx.compose.runtime.rememberUpdatedState(refreshing)
+    androidx.compose.runtime.LaunchedEffect(state) {
+        androidx.compose.runtime.snapshotFlow { state.distanceFraction >= 1f }
+            .collect { far -> if (far && !busy.value) haptic.performHapticFeedback(androidx.compose.ui.hapticfeedback.HapticFeedbackType.GestureThresholdActivate) }
+    }
+    androidx.compose.material3.pulltorefresh.PullToRefreshBox(
+        isRefreshing = refreshing,
+        onRefresh = onRefresh,
+        state = state,
+        modifier = modifier,
+        indicator = {
+            androidx.compose.material3.pulltorefresh.PullToRefreshDefaults.LoadingIndicator(
+                state = state,
+                isRefreshing = refreshing,
+                modifier = Modifier.align(androidx.compose.ui.Alignment.TopCenter),
+            )
+        },
+        content = content,
+    )
+}

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Notes.kt

@@ -2,6 +2,11 @@
 
 package org.xtimms.psu.schedule.ui
 
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.delay
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.platform.LocalHapticFeedback
+import androidx.compose.ui.hapticfeedback.HapticFeedbackType
 import androidx.compose.ui.draw.clip
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material.icons.rounded.CalendarToday
@@ -9,7 +14,13 @@ import androidx.compose.material3.rememberDatePickerState
 import androidx.compose.material3.OutlinedButton
 import androidx.compose.material3.DatePickerDialog
 import androidx.compose.material3.DatePicker
+import androidx.compose.foundation.background
 import androidx.compose.foundation.clickable
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.rounded.Image
+import androidx.compose.ui.platform.LocalContext
+import org.xtimms.psu.schedule.app
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
@@ -111,6 +122,11 @@ fun MainViewModel.nextOccurrence(t: Timetable, subject: String, after: LocalDate
 @Composable
 fun NoteRow(note: Note, onToggle: () -> Unit, onClick: () -> Unit, showSubject: Boolean, showDue: Boolean = true) {
     val overdue = note.overdue()
+    var viewing by remember { mutableStateOf(false) }
+    val haptic = LocalHapticFeedback.current
+    // A ticked task is struck through in place first, then moves down to the done ones.
+    var shownDone by remember(note.id, note.done) { mutableStateOf(note.done) }
+    val scope = rememberCoroutineScope()
     Row(
         verticalAlignment = Alignment.CenterVertically,
         modifier = Modifier
@@ -119,20 +135,20 @@ fun NoteRow(note: Note, onToggle: () -> Unit, onClick: () -> Unit, showSubject:
             .clickable(onClickLabel = "Изменить", role = Role.Button, onClick = onClick)
             .padding(start = 8.dp, end = 16.dp, top = 2.dp, bottom = 2.dp),
     ) {
-        if (note.task) Checkbox(checked = note.done, onCheckedChange = { onToggle() })
+        if (note.task) Checkbox(checked = shownDone, onCheckedChange = { done ->
+            haptic.performHapticFeedback(if (done) HapticFeedbackType.Confirm else HapticFeedbackType.ToggleOff)
+            shownDone = done
+            if (done) scope.launch {
+                delay(DONE_PAUSE)
+                onToggle()
+            } else onToggle()
+        })
         else Box(Modifier.size(48.dp), contentAlignment = Alignment.Center) {
             Icon(Icons.Rounded.StickyNote2, contentDescription = "Заметка", tint = MaterialTheme.colorScheme.onSurfaceVariant)
         }
         Spacer(Modifier.width(8.dp))
         Column(Modifier.weight(1f).padding(vertical = 8.dp)) {
-            Text(
+            StrikeText(note.text, done = note.task && shownDone, style = MaterialTheme.typography.bodyLarge, maxLines = 3)
-                note.text,
-                style = MaterialTheme.typography.bodyLarge,
-                textDecoration = if (note.task && note.done) TextDecoration.LineThrough else null,
-                color = if (note.task && note.done) MaterialTheme.colorScheme.onSurfaceVariant else MaterialTheme.colorScheme.onSurface,
-                maxLines = 3,
-                overflow = TextOverflow.Ellipsis,
-            )
             Row(verticalAlignment = Alignment.CenterVertically) {
                 if (showSubject && !note.general) {
                     SubjectDot(note.subject, 8.dp)
@@ -155,7 +171,22 @@ fun NoteRow(note: Note, onToggle: () -> Unit, onClick: () -> Unit, showSubject:
                 )
             }
         }
+        // The first photo, with how many more; it opens the viewer, the row the editor.
+        if (note.photos.isNotEmpty()) Box(Modifier.padding(start = 12.dp)) {
+            PhotoThumb(note.photos.first(), 48.dp, onClick = { viewing = true })
+            if (note.photos.size > 1) Text(
+                "+${note.photos.size - 1}",
+                style = MaterialTheme.typography.labelMedium,
+                color = MaterialTheme.colorScheme.inverseOnSurface,
+                modifier = Modifier
+                    .align(Alignment.BottomEnd)
+                    .padding(3.dp)
+                    .background(MaterialTheme.colorScheme.inverseSurface.copy(alpha = 0.85f), MaterialTheme.shapes.small)
+                    .padding(horizontal = 5.dp),
+            )
+        }
     }
+    if (viewing) PhotoViewer(note.photos, 0) { viewing = false }
 }
 
 /** What the editor needs to file a new note: the lesson it opened from and the next one. */
@@ -182,11 +213,19 @@ fun NoteEditor(
     val general = editing?.general ?: (target?.subject?.isBlank() == true)
     var day by rememberSaveable { mutableStateOf((editing?.date?.let(::parseDate) ?: target?.date ?: today()).toEpochDay()) }
     var picking by remember { mutableStateOf(false) }
+    // Photos of this edit; the ones added here go from the disk again if it is not saved.
+    var photos by rememberSaveable { mutableStateOf(editing?.photos.orEmpty()) }
+    var added by rememberSaveable { mutableStateOf(emptyList<String>()) }
+    val store = LocalContext.current.app.notes
+    val cancel = {
+        store.discard(added)
+        onDismiss()
+    }
     val focus = remember { FocusRequester() }
     LaunchedEffect(Unit) { focus.requestFocus() }
 
     AlertDialog(
-        onDismissRequest = onDismiss,
+        onDismissRequest = cancel,
         icon = { Icon(if (task) Icons.AutoMirrored.Rounded.Assignment else Icons.Rounded.StickyNote2, contentDescription = null) },
         title = {
             Text(
@@ -198,7 +237,7 @@ fun NoteEditor(
             )
         },
         text = {
-            Column(verticalArrangement = Arrangement.spacedBy(12.dp)) {
+            Column(verticalArrangement = Arrangement.spacedBy(12.dp), modifier = Modifier.verticalScroll(rememberScrollState())) {
                 ConnectedChoice(
                     options = listOf(true to "Задание", false to "Заметка"),
                     selected = task,
@@ -212,6 +251,19 @@ fun NoteEditor(
                     keyboardOptions = KeyboardOptions(capitalization = KeyboardCapitalization.Sentences),
                     modifier = Modifier.fillMaxWidth().heightIn(min = 96.dp).focusRequester(focus),
                 )
+                // A photo of the board or the assignment instead of copying it out.
+                NotePhotosEditor(
+                    photos = photos,
+                    onAdd = { photos = photos + it; added = added + it },
+                    onRemove = { name ->
+                        photos = photos - name
+                        // A photo added in this edit has no saved note to keep it.
+                        if (name in added) {
+                            added = added - name
+                            store.discard(listOf(name))
+                        }
+                    },
+                )
                 if (general) {
                     Text("День", style = MaterialTheme.typography.labelLarge, color = MaterialTheme.colorScheme.onSurfaceVariant)
                     OutlinedButton(onClick = { picking = true }, modifier = Modifier.fillMaxWidth()) {
@@ -241,7 +293,8 @@ fun NoteEditor(
         },
         confirmButton = {
             TextButton(
-                enabled = text.isNotBlank(),
+                // A photo alone is a note too: "задание на фото".
+                enabled = text.isNotBlank() || photos.isNotEmpty(),
                 onClick = {
                     val base = editing ?: run {
                         val t = target ?: return@TextButton
@@ -249,16 +302,16 @@ fun NoteEditor(
                         Note(group = groupKey, subject = t.subject, date = date.toString(), start = start, text = "")
                     }
                     val dated = if (general) base.copy(date = LocalDate.ofEpochDay(day).toString()) else base
-                    onSave(dated.copy(text = text.trim(), task = task))
+                    onSave(dated.copy(text = text.trim().ifEmpty { "Фото" }, task = task, photos = photos))
                 },
             ) { Text("Сохранить") }
         },
         dismissButton = {
             Row {
-                if (editing != null) TextButton(onClick = { onDelete(editing) }) {
+                if (editing != null) TextButton(onClick = { store.discard(added); onDelete(editing) }) {
                     Text("Удалить", color = MaterialTheme.colorScheme.error)
                 }
-                TextButton(onClick = onDismiss) { Text("Отмена") }
+                TextButton(onClick = cancel) { Text("Отмена") }
             }
         },
     )
@@ -280,6 +333,7 @@ fun NoteEditor(
 /** The lesson sheet's section: this lesson's tasks and notes and a button to add one. */
 @Composable
 fun LessonNotes(vm: MainViewModel, lesson: Lesson, date: LocalDate) {
+    val undo = LocalUndo.current
     val all by vm.notes.collectAsStateWithLifecycle()
     val timetable by vm.timetable.collectAsStateWithLifecycle()
     val settings by vm.settings.collectAsStateWithLifecycle()
@@ -317,7 +371,7 @@ fun LessonNotes(vm: MainViewModel, lesson: Lesson, date: LocalDate) {
             editing = editing,
             groupKey = group,
             onSave = { vm.saveNote(it); adding = false; editing = null },
-            onDelete = { vm.deleteNote(it.id); editing = null },
+            onDelete = { vm.deleteNote(it.id, undo); editing = null },
             onDismiss = { adding = false; editing = null },
         )
     }
@@ -342,6 +396,11 @@ fun NotesHint(notes: List<Note>, color: androidx.compose.ui.graphics.Color) {
             color = color,
             maxLines = 1,
             overflow = TextOverflow.Ellipsis,
+            modifier = Modifier.weight(1f, fill = false),
         )
+        if (open.any { it.photos.isNotEmpty() }) {
+            Spacer(Modifier.width(6.dp))
+            Icon(Icons.Rounded.Image, contentDescription = "С фото", tint = color, modifier = Modifier.size(18.dp))
+        }
     }
 }

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Onboarding.kt

@@ -51,6 +51,8 @@ import androidx.compose.material.icons.automirrored.rounded.KeyboardArrowRight
 import androidx.compose.material.icons.rounded.CalendarMonth
 import androidx.compose.material.icons.rounded.Checklist
 import androidx.compose.material.icons.rounded.Groups
+import androidx.compose.material.icons.rounded.Check
+import org.xtimms.psu.schedule.data.choiceKey
 import androidx.compose.material.icons.rounded.NotificationsActive
 import androidx.compose.material.icons.rounded.DownloadForOffline
 import androidx.compose.material3.Button
@@ -93,14 +95,15 @@ import org.xtimms.psu.schedule.ui.theme.page
 import kotlin.coroutines.cancellation.CancellationException
 
 /** The first run, in the order a student needs it: what this is, their group, their subgroup, reminders. */
-private enum class Step { Welcome, Group, Subgroup, Reminders }
+private enum class Step { Welcome, Group, Subgroup, Choice, Foreign, Reminders }
 
 /** Text and controls of the onboarding pages keep to a phone's width on tablets. */
 private val PAGE_WIDTH = 560.dp
 
 /**
  * First-run onboarding. Only the group is required: the welcome leads straight to it,
- * the subgroup page appears only for groups split into subgroups, and reminders can wait.
+ * the subgroup page appears only for groups split into subgroups, the choice page only for groups
+ * whose parts study one subject or another (German or French), and reminders can wait.
  * [onDone] opens the overview with the chosen group.
  */
 @Composable
@@ -108,14 +111,18 @@ fun Onboarding(vm: MainViewModel, onDone: () -> Unit) {
     val timetable by vm.timetable.collectAsStateWithLifecycle()
     val settings by vm.settings.collectAsStateWithLifecycle()
     val subgroups = timetable?.subgroups.orEmpty()
+    val choices = timetable?.choices.orEmpty()
     var step by rememberSaveable { mutableStateOf(Step.Welcome) }
     // The steps the progress bar counts; the welcome is not one of them.
-    val steps = if (subgroups.isEmpty()) listOf(Step.Group, Step.Reminders) else listOf(Step.Group, Step.Subgroup, Step.Reminders)
+    val steps = listOfNotNull(
-    fun previous(of: Step): Step = when (of) {
+        Step.Group,
-        Step.Welcome, Step.Group -> Step.Welcome
+        Step.Subgroup.takeIf { subgroups.isNotEmpty() },
-        Step.Subgroup -> Step.Group
+        Step.Choice.takeIf { choices.isNotEmpty() },
-        Step.Reminders -> if (subgroups.isEmpty()) Step.Group else Step.Subgroup
+        Step.Foreign.takeIf { timetable?.audience == true },
-    }
+        Step.Reminders,
+    )
+    fun previous(of: Step): Step = if (of == Step.Welcome) Step.Welcome else steps.getOrNull(steps.indexOf(of) - 1) ?: Step.Welcome
+    fun next(of: Step): Step = steps.getOrNull(steps.indexOf(of) + 1) ?: Step.Reminders
 
     // Predictive back, as in the rest of the app: the gesture scrubs the way back to the previous step.
     val state = remember { SeekableTransitionState(step) }
@@ -162,7 +169,16 @@ fun Onboarding(vm: MainViewModel, onDone: () -> Unit) {
                 Step.Welcome -> Welcome(onStart = { step = Step.Group })
                 Step.Group -> GroupsScreen(
                     vm,
-                    onOpened = { step = if (vm.timetable.value?.subgroups.isNullOrEmpty()) Step.Reminders else Step.Subgroup },
+                    // The steps above still count the previous group's timetable: read the new one.
+                    onOpened = {
+                        val t = vm.timetable.value
+                        step = when {
+                            !t?.subgroups.isNullOrEmpty() -> Step.Subgroup
+                            !t?.choices.isNullOrEmpty() -> Step.Choice
+                            t?.audience == true -> Step.Foreign
+                            else -> Step.Reminders
+                        }
+                    },
                     onBack = null,
                     onboarding = true,
                 )
@@ -170,7 +186,18 @@ fun Onboarding(vm: MainViewModel, onDone: () -> Unit) {
                     group = timetable?.group.orEmpty(),
                     subgroups = subgroups,
                     selected = settings?.subgroup,
-                    onPick = { vm.setSubgroup(it); step = Step.Reminders },
+                    onPick = { vm.setSubgroup(it); step = next(Step.Subgroup) },
+                )
+                Step.Choice -> ChoiceStep(
+                    group = timetable?.group.orEmpty(),
+                    choices = choices,
+                    taken = settings?.choices.orEmpty(),
+                    onPick = vm::setChoice,
+                    onNext = { step = next(Step.Choice) },
+                )
+                Step.Foreign -> ForeignStep(
+                    group = timetable?.group.orEmpty(),
+                    onPick = { vm.setForeign(it); step = Step.Reminders },
                 )
                 Step.Reminders -> RemindersStep(
                     minutes = settings?.reminderMinutes ?: 10,
@@ -441,6 +468,75 @@ private fun SubgroupStep(group: String, subgroups: List<String>, selected: Strin
     }
 }
 
+/**
+ * "Что вы изучаете": German or French, say. With one choice a tap picks and moves on; with
+ * several, each list keeps its pick and "Далее" moves on.
+ */
+@Composable
+private fun ChoiceStep(
+    group: String,
+    choices: List<List<String>>,
+    taken: Map<String, String>,
+    onPick: (List<String>, String?) -> Unit,
+    onNext: () -> Unit,
+) {
+    StepPage(
+        centered = false,
+        buttons = {
+            if (choices.size > 1) PrimaryButton("Далее", onNext)
+            TextButton(onClick = onNext) { Text("Пропустить") }
+        },
+    ) {
+        StepHeading(Icons.Rounded.Groups, "Что вы изучаете?", choiceText(group, choices.first()))
+        choices.forEachIndexed { n, options ->
+            if (n > 0) Spacer(Modifier.height(16.dp))
+            SegmentedList {
+                val all = options + listOf<String?>(null)
+                all.forEachIndexed { i, option ->
+                    SegmentedItem(
+                        index = i,
+                        count = all.size,
+                        headline = option ?: "Показывать всё",
+                        supporting = if (option == null) "Занятия всех вариантов" else null,
+                        onClick = {
+                            onPick(options, option)
+                            if (choices.size == 1) onNext()
+                        },
+                        trailing = {
+                            if (choices.size > 1 && taken[choiceKey(options)] == option) Icon(Icons.Rounded.Check, contentDescription = "Выбрано")
+                            else Icon(Icons.AutoMirrored.Rounded.KeyboardArrowRight, contentDescription = null)
+                        },
+                    )
+                }
+            }
+        }
+    }
+}
+
+/** "Вы иностранный студент?" as a page: one tap answers and moves on. */
+@Composable
+private fun ForeignStep(group: String, onPick: (Boolean?) -> Unit) {
+    StepPage(
+        centered = false,
+        buttons = { TextButton(onClick = { onPick(null) }) { Text("Пропустить") } },
+    ) {
+        StepHeading(Icons.Rounded.Groups, "Вы иностранный студент?", foreignText(group))
+        SegmentedList {
+            val answers = listOf<Pair<Boolean?, String>>(true to "Да, иностранный", false to "Нет", null to "Показывать всё")
+            answers.forEachIndexed { i, (value, label) ->
+                SegmentedItem(
+                    index = i,
+                    count = answers.size,
+                    headline = label,
+                    supporting = if (value == null) "Пары для всех студентов" else null,
+                    onClick = { onPick(value) },
+                    trailing = { Icon(Icons.AutoMirrored.Rounded.KeyboardArrowRight, contentDescription = null) },
+                )
+            }
+        }
+    }
+}
+
 /** Reminders before each lesson; Android asks for the notification permission here, when it makes sense. */
 @Composable
 private fun RemindersStep(minutes: Int, onMinutes: (Int) -> Unit, onDone: (Boolean) -> Unit) {

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Photos.kt

@@ -0,0 +1,274 @@
+package org.xtimms.psu.schedule.ui
+
+import android.graphics.BitmapFactory
+import android.net.Uri
+import android.util.LruCache
+import androidx.activity.compose.rememberLauncherForActivityResult
+import androidx.activity.result.PickVisualMediaRequest
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.gestures.detectTapGestures
+import androidx.compose.foundation.gestures.awaitEachGesture
+import androidx.compose.foundation.gestures.awaitFirstDown
+import androidx.compose.foundation.gestures.calculatePan
+import androidx.compose.foundation.gestures.calculateZoom
+import androidx.compose.foundation.horizontalScroll
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.statusBarsPadding
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.pager.HorizontalPager
+import androidx.compose.foundation.pager.rememberPagerState
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.rounded.Close
+import androidx.compose.material.icons.rounded.PhotoCamera
+import androidx.compose.material.icons.rounded.PhotoLibrary
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.FilledIconButton
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.IconButtonDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.mutableIntStateOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.produceState
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.ImageBitmap
+import androidx.compose.ui.graphics.asImageBitmap
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.input.pointer.pointerInput
+import androidx.compose.ui.input.pointer.positionChanged
+import androidx.compose.ui.layout.ContentScale
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.window.Dialog
+import androidx.compose.ui.window.DialogProperties
+import androidx.core.content.FileProvider
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import org.xtimms.psu.schedule.app
+import java.io.File
+
+// Photos of the board or the assignment, pinned to a task or a note (NotesStore keeps the files).
+
+/** Decoded thumbnails, so lists scrolling past the same photos do not decode them again. */
+private val thumbnails = object : LruCache<String, ImageBitmap>(24 * 1024 * 1024) {
+    override fun sizeOf(key: String, value: ImageBitmap) = value.width * value.height * 4
+}
+
+/** A photo decoded no larger than [max] pixels on its long side; null while it loads. */
+@Composable
+private fun rememberPhoto(file: File, max: Int): ImageBitmap? {
+    val key = "${file.name}@$max"
+    return produceState(thumbnails.get(key), key) {
+        if (value != null) return@produceState
+        value = withContext(Dispatchers.IO) {
+            runCatching {
+                val bounds = BitmapFactory.Options().apply { inJustDecodeBounds = true }
+                BitmapFactory.decodeFile(file.path, bounds)
+                var sample = 1
+                while (maxOf(bounds.outWidth, bounds.outHeight) / (sample * 2) >= max) sample *= 2
+                BitmapFactory.decodeFile(file.path, BitmapFactory.Options().apply { inSampleSize = sample })?.asImageBitmap()
+            }.getOrNull()
+        }?.also { thumbnails.put(key, it) }
+    }.value
+}
+
+/** A square thumbnail; [onClick] opens the viewer. */
+@Composable
+fun PhotoThumb(name: String, size: Dp, onClick: (() -> Unit)?, modifier: Modifier = Modifier) {
+    val store = LocalContext.current.app.notes
+    val px = with(LocalDensity.current) { size.roundToPx() } * 2
+    val image = rememberPhoto(store.photo(name), px)
+    Box(
+        modifier
+            .size(size)
+            .clip(MaterialTheme.shapes.medium)
+            .background(MaterialTheme.colorScheme.surfaceContainerHighest)
+            .then(if (onClick != null) Modifier.clickable(onClickLabel = "Открыть фото", onClick = onClick) else Modifier),
+    ) {
+        image?.let { Image(it, contentDescription = "Фото", contentScale = ContentScale.Crop, modifier = Modifier.fillMaxSize()) }
+    }
+}
+
+/**
+ * The editor's photos: thumbnails with a remove button, then "Снять" (the camera app) and
+ * "Галерея" (the system photo picker, no storage permission needed).
+ */
+@Composable
+fun NotePhotosEditor(photos: List<String>, onAdd: (String) -> Unit, onRemove: (String) -> Unit) {
+    val context = LocalContext.current
+    val store = context.app.notes
+    val scope = rememberCoroutineScope()
+    var loading by remember { mutableIntStateOf(0) }
+    var viewing by remember { mutableStateOf<Int?>(null) }
+    fun import(uris: List<Uri>) {
+        uris.forEach { uri ->
+            loading++
+            scope.launch {
+                store.importPhoto(uri)?.let(onAdd)
+                loading--
+            }
+        }
+    }
+    // The camera app writes the full-size shot here; the store keeps a smaller copy.
+    val shot = remember { File(context.cacheDir, "camera/shot.jpg") }
+    val camera = rememberLauncherForActivityResult(ActivityResultContracts.TakePicture()) { taken ->
+        if (taken) {
+            loading++
+            scope.launch {
+                store.importPhoto(Uri.fromFile(shot))?.let(onAdd)
+                shot.delete()
+                loading--
+            }
+        }
+    }
+    val gallery = rememberLauncherForActivityResult(ActivityResultContracts.PickMultipleVisualMedia(MAX_PHOTOS)) { import(it) }
+    val room = MAX_PHOTOS - photos.size
+
+    Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
+        if (photos.isNotEmpty() || loading > 0) Row(
+            horizontalArrangement = Arrangement.spacedBy(8.dp),
+            modifier = Modifier.horizontalScroll(rememberScrollState()),
+        ) {
+            photos.forEachIndexed { index, name ->
+                Box {
+                    PhotoThumb(name, 72.dp, onClick = { viewing = index })
+                    FilledIconButton(
+                        onClick = { onRemove(name) },
+                        colors = IconButtonDefaults.filledIconButtonColors(
+                            containerColor = MaterialTheme.colorScheme.inverseSurface,
+                            contentColor = MaterialTheme.colorScheme.inverseOnSurface,
+                        ),
+                        modifier = Modifier.align(Alignment.TopEnd).padding(4.dp).size(24.dp),
+                    ) { Icon(Icons.Rounded.Close, contentDescription = "Убрать фото", modifier = Modifier.size(16.dp)) }
+                }
+            }
+            repeat(loading) {
+                Box(
+                    Modifier.size(72.dp).clip(MaterialTheme.shapes.medium).background(MaterialTheme.colorScheme.surfaceContainerHighest),
+                    contentAlignment = Alignment.Center,
+                ) { CircularProgressIndicator(Modifier.size(24.dp), strokeWidth = 2.dp) }
+            }
+        }
+        if (room > 0) Row(horizontalArrangement = Arrangement.spacedBy(8.dp), modifier = Modifier.fillMaxWidth()) {
+            OutlinedButton(
+                onClick = {
+                    shot.parentFile?.mkdirs()
+                    val uri = FileProvider.getUriForFile(context, context.packageName + ".photos", shot)
+                    // A phone without a camera app: the gallery is still there.
+                    runCatching { camera.launch(uri) }
+                },
+                modifier = Modifier.weight(1f),
+            ) {
+                Icon(Icons.Rounded.PhotoCamera, contentDescription = null, modifier = Modifier.size(18.dp))
+                Spacer(Modifier.width(8.dp))
+                Text("Снять", maxLines = 1)
+            }
+            OutlinedButton(
+                onClick = { gallery.launch(PickVisualMediaRequest(ActivityResultContracts.PickVisualMedia.ImageOnly)) },
+                modifier = Modifier.weight(1f),
+            ) {
+                Icon(Icons.Rounded.PhotoLibrary, contentDescription = null, modifier = Modifier.size(18.dp))
+                Spacer(Modifier.width(8.dp))
+                Text("Галерея", maxLines = 1)
+            }
+        }
+    }
+    viewing?.let { PhotoViewer(photos, it) { viewing = null } }
+}
+
+/** Photos full screen, swiped sideways; pinch or double-tap to zoom into the board. */
+@Composable
+fun PhotoViewer(photos: List<String>, start: Int, onDismiss: () -> Unit) {
+    if (photos.isEmpty()) return
+    val store = LocalContext.current.app.notes
+    Dialog(onDismissRequest = onDismiss, properties = DialogProperties(usePlatformDefaultWidth = false)) {
+        val pager = rememberPagerState(initialPage = start.coerceIn(0, photos.lastIndex)) { photos.size }
+        Box(Modifier.fillMaxSize().background(Color.Black)) {
+            HorizontalPager(state = pager, modifier = Modifier.fillMaxSize()) { page ->
+                var scale by remember { mutableFloatStateOf(1f) }
+                var offset by remember { mutableStateOf(Offset.Zero) }
+                val image = rememberPhoto(store.photo(photos[page]), 2048)
+                Box(
+                    Modifier
+                        .fillMaxSize()
+                        .pointerInput(Unit) {
+                            detectTapGestures(onDoubleTap = {
+                                if (scale > 1f) { scale = 1f; offset = Offset.Zero } else scale = 2.5f
+                            })
+                        }
+                        .pointerInput(Unit) {
+                            // Two fingers zoom; one finger pans only while zoomed in, so at 1x the
+                            // pager still takes the swipe to the next photo.
+                            awaitEachGesture {
+                                awaitFirstDown(requireUnconsumed = false)
+                                do {
+                                    val event = awaitPointerEvent()
+                                    if (event.changes.size > 1 || scale > 1f) {
+                                        scale = (scale * event.calculateZoom()).coerceIn(1f, 5f)
+                                        offset = if (scale > 1f) offset + event.calculatePan() else Offset.Zero
+                                        event.changes.forEach { if (it.positionChanged()) it.consume() }
+                                    }
+                                } while (event.changes.any { it.pressed })
+                            }
+                        },
+                    contentAlignment = Alignment.Center,
+                ) {
+                    if (image == null) CircularProgressIndicator(color = Color.White)
+                    else Image(
+                        image,
+                        contentDescription = "Фото ${page + 1} из ${photos.size}",
+                        contentScale = ContentScale.Fit,
+                        modifier = Modifier.fillMaxSize().graphicsLayer {
+                            scaleX = scale
+                            scaleY = scale
+                            translationX = offset.x
+                            translationY = offset.y
+                        },
+                    )
+                }
+            }
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                modifier = Modifier.fillMaxWidth().statusBarsPadding().padding(8.dp),
+            ) {
+                IconButton(onClick = onDismiss) { Icon(Icons.Rounded.Close, contentDescription = "Закрыть", tint = Color.White) }
+                Spacer(Modifier.weight(1f))
+                if (photos.size > 1) Surface(shape = CircleShape, color = Color.Black.copy(alpha = 0.5f), contentColor = Color.White) {
+                    Text("${pager.currentPage + 1} / ${photos.size}", style = MaterialTheme.typography.labelLarge, modifier = Modifier.padding(horizontal = 12.dp, vertical = 6.dp))
+                }
+            }
+        }
+    }
+}
+
+/** Up to this many photos per task or note. */
+const val MAX_PHOTOS = 6

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/PlansScreen.kt

@@ -28,6 +28,7 @@ import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.navigationBarsPadding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.lazy.LazyColumn
@@ -119,22 +120,33 @@ private sealed interface Row {
  */
 @Composable
 fun PlansScreen(vm: MainViewModel, nav: AppNav) {
+    val undo = LocalUndo.current
     val all by vm.notes.collectAsStateWithLifecycle()
     val timetable by vm.timetable.collectAsStateWithLifecycle()
     val settings by vm.settings.collectAsStateWithLifecycle()
     val prefs = settings?.plans ?: PlansPrefs()
     var editing by remember { mutableStateOf<Note?>(null) }
-    var adding by remember { mutableStateOf(false) }
+    var target by remember { mutableStateOf<NoteTarget?>(null) }
+    // "+" grows into the sheet of a new plan (Morph.kt); a shortcut opens it from the middle.
+    val morph = LocalMorph.current
+    val addPlan = {
+        morph?.open(MorphKind.Sheet) { close ->
+            AddPlanSheet(vm, timetable, settings?.subgroup, day = null) {
+                close()
+                target = it
+            }
+        }
+        Unit
+    }
     val wantsTask by vm.newTask.collectAsStateWithLifecycle()
     LaunchedEffect(wantsTask) {
         if (wantsTask) {
-            adding = true
+            addPlan()
             vm.newTask.value = false
         }
     }
     var tuning by remember { mutableStateOf(false) }
-    var details by remember { mutableStateOf<Pair<Lesson, LocalDate>?>(null) }
+    val openLesson = rememberLessonOpener(vm)
-    var target by remember { mutableStateOf<NoteTarget?>(null) }
     var date by remember { mutableStateOf(today()) }
     // Each layout keeps its own list, so the outgoing and incoming layouts can be on screen
     // together while one fades through to the other.
@@ -174,11 +186,15 @@ fun PlansScreen(vm: MainViewModel, nav: AppNav) {
             title = {
                 Column {
                     Text("Планы", style = MaterialTheme.typography.titleLargeEmphasized)
-                    Text(
+                    androidx.compose.foundation.layout.Row(verticalAlignment = Alignment.CenterVertically) {
-                        if (open == 0) "Всё сделано" else "$open ${plural(open, "дело", "дела", "дел")} впереди",
+                        // The last task done: a check pops up by "Всё сделано".
-                        style = MaterialTheme.typography.bodyMedium,
+                        DoneMark(open == 0)
-                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        Text(
-                    )
+                            if (open == 0) "Всё сделано" else "$open ${plural(open, "дело", "дела", "дел")} впереди",
+                            style = MaterialTheme.typography.bodyMedium,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        )
+                    }
                 }
             },
             actions = {
@@ -254,7 +270,7 @@ fun PlansScreen(vm: MainViewModel, nav: AppNav) {
                         DetailPane(it) {
                             DayAgenda(
                                 vm, timetable, settings?.subgroup, date, all,
-                                onLesson = { details = it to date },
+                                onLesson = { openLesson(it, date) },
                                 onNote = { editing = it },
                                 modifier = Modifier.fillMaxSize().padding(top = 12.dp),
                             )
@@ -265,30 +281,22 @@ fun PlansScreen(vm: MainViewModel, nav: AppNav) {
             }
         }
         FloatingActionButton(
-            onClick = { adding = true },
+            onClick = addPlan,
-            modifier = Modifier.align(Alignment.BottomEnd).padding(end = 16.dp, bottom = 16.dp + navBarPadding()),
+            modifier = Modifier
+                .align(Alignment.BottomEnd)
+                .padding(end = 16.dp, bottom = 16.dp + navBarPadding())
+                .morphOrigin("fab|plans", MaterialTheme.colorScheme.primaryContainer, 16.dp),
         ) { Icon(Icons.Rounded.Add, contentDescription = "Новое задание") }
     }
 
-    details?.let { (lesson, d) ->
-        ModalBottomSheet(onDismissRequest = { details = null }) {
-            LessonDetails(lesson, timetable?.bells.orEmpty(), d, vm, onClose = { details = null })
-        }
-    }
     if (tuning) ModalBottomSheet(onDismissRequest = { tuning = false }) { PlansSettings(prefs, vm::setPlans) }
     val group = vm.currentGroupKey()
-    if (adding) ModalBottomSheet(onDismissRequest = { adding = false }) {
-        AddPlanSheet(vm, timetable, settings?.subgroup, day = null) {
-            adding = false
-            target = it
-        }
-    }
     if (group != null && (target != null || editing != null)) NoteEditor(
         target = target,
         editing = editing,
         groupKey = editing?.group ?: group,
         onSave = { vm.saveNote(it); target = null; editing = null },
-        onDelete = { vm.deleteNote(it.id); editing = null },
+        onDelete = { vm.deleteNote(it.id, undo); editing = null },
         onDismiss = { target = null; editing = null },
     )
 }
@@ -564,6 +572,7 @@ internal fun AddPlanSheet(vm: MainViewModel, t: Timetable?, subgroup: String?, d
     Column(
         Modifier
             .verticalScroll(rememberScrollState())
+            .navigationBarsPadding()
             .padding(start = 24.dp, end = 24.dp, bottom = 32.dp),
         verticalArrangement = Arrangement.spacedBy(10.dp),
     ) {

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/ScheduleScreen.kt

@@ -2,6 +2,10 @@
 
 package org.xtimms.psu.schedule.ui
 
+import androidx.compose.animation.core.tween
+import kotlinx.coroutines.flow.drop
+import androidx.compose.ui.platform.LocalHapticFeedback
+import androidx.compose.ui.hapticfeedback.HapticFeedbackType
 import androidx.compose.ui.unit.Dp
 import androidx.compose.animation.togetherWith
 import androidx.compose.animation.Crossfade
@@ -19,6 +23,7 @@ import androidx.compose.foundation.interaction.collectIsDraggedAsState
 import androidx.compose.material.icons.rounded.VisibilityOff
 import androidx.compose.material3.OutlinedButton
 import org.xtimms.psu.schedule.data.hideKey
+import org.xtimms.psu.schedule.data.hiddenIn
 import androidx.compose.runtime.snapshotFlow
 import androidx.compose.ui.graphics.Color
 import kotlin.math.abs
@@ -33,6 +38,7 @@ import androidx.compose.foundation.background
 import androidx.compose.foundation.layout.widthIn
 import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.foundation.layout.windowInsetsPadding
+import androidx.compose.foundation.layout.systemBars
 import androidx.compose.foundation.layout.statusBars
 import androidx.compose.foundation.layout.WindowInsets
 import androidx.compose.material.icons.rounded.Today
@@ -81,16 +87,15 @@ import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.ExperimentalMaterial3ExpressiveApi
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
-import androidx.compose.material3.LoadingIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.ModalBottomSheet
 import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
 import androidx.compose.material3.TopAppBar
-import androidx.compose.material3.pulltorefresh.PullToRefreshBox
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
@@ -128,12 +133,12 @@ fun ScheduleScreen(
     val timetable by vm.timetable.collectAsStateWithLifecycle()
     val settings by vm.settings.collectAsStateWithLifecycle()
     val status by vm.status.collectAsStateWithLifecycle()
-    var details by remember { mutableStateOf<Pair<Lesson, LocalDate?>?>(null) }
+    val openLesson = rememberLessonOpener(vm)
     val subgroup = settings?.subgroup
     val t = timetable
 
     if (t?.semester != null) {
-        Planner(vm, nav, t, subgroup, weekView, onWeekView, focus, onFocusHandled, onOpen = { lesson, date -> details = lesson to date })
+        Planner(vm, nav, t, subgroup, weekView, onWeekView, focus, onFocusHandled, onOpen = { lesson, date -> openLesson(lesson, date) })
     } else Column(Modifier.fillMaxSize()) {
         TopAppBar(
             colors = appBarColors(),
@@ -143,7 +148,7 @@ fun ScheduleScreen(
         )
         status.message?.let { Banner(it, offline = status.offline, onClose = vm::dismissMessage, onRetry = if (status.offline) vm::retry else null, action = if (status.needsGroup) "Выбрать группу" to nav.openGroups else null) }
         when {
-            t == null && status.loading -> Box(Modifier.fillMaxSize(), contentAlignment = Alignment.Center) { LoadingIndicator() }
+            t == null && status.loading -> ScheduleSkeleton()
             t == null -> CenteredEmpty {
                 Empty(
                     "Расписание не загружено",
@@ -153,12 +158,7 @@ fun ScheduleScreen(
                     action = if (settings?.current != null) "Повторить" to { vm.refresh(); Unit } else "Выбрать группу" to nav.openGroups,
                 )
             }
-            else -> WordRows(t, subgroup, settings?.hidden.orEmpty(), onOpen = { details = it to null })
+            else -> WordRows(t, subgroup, settings?.hidden.orEmpty(), onOpen = { openLesson(it, null) })
-        }
-    }
-    details?.let { (lesson, date) ->
-        ModalBottomSheet(onDismissRequest = { details = null }) {
-            LessonDetails(lesson, timetable?.bells.orEmpty(), date, vm, onClose = { details = null })
         }
     }
 }
@@ -233,6 +233,17 @@ private fun Planner(
         }
     }
 
+    // A finger swipe to another day ticks like a tap on the strip.
+    val haptic = LocalHapticFeedback.current
+    val draggingDays by pager.interactionSource.collectIsDraggedAsState()
+    var daySwiped by remember { mutableStateOf(false) }
+    LaunchedEffect(draggingDays) { if (draggingDays) daySwiped = true }
+    LaunchedEffect(pager) {
+        snapshotFlow { pager.settledPage }.drop(1).collect {
+            if (daySwiped) haptic.performHapticFeedback(HapticFeedbackType.SegmentTick)
+            daySwiped = false
+        }
+    }
     // The strip is a pager of weeks: it follows the day pager, and swiping it moves the days.
     val strip = rememberPagerState(initialPage = mondays.indexOf(date.monday()).coerceAtLeast(0)) { mondays.size }
     LaunchedEffect(date.monday()) {
@@ -336,6 +347,7 @@ private fun Planner(
                         enabled = { d -> dates.contains(d) },
                         onSelect = ::go,
                         onWeek = ::week,
+                        marks = true,
                         modifier = Modifier.widthIn(max = MAX_CONTENT).padding(horizontal = 8.dp),
                     )
                 }
@@ -382,7 +394,8 @@ private fun Planner(
                         modifier = if (wide) Modifier.padding(top = 16.dp) else Modifier,
                     )
                 }
-            } else PullToRefreshBox(isRefreshing = status.loading, onRefresh = { vm.refresh() }) {
+            } else ExpressiveRefresh(refreshing = status.loading, onRefresh = { vm.refresh() }) {
+                val fresh by vm.fresh.collectAsStateWithLifecycle()
                 HorizontalPager(state = pager, modifier = Modifier.fillMaxSize()) { page ->
                     val pageDate = dates[page]
                     DayPage(
@@ -390,6 +403,8 @@ private fun Planner(
                         slots = vm.slotsOn(t, pageDate, subgroup),
                         places = vm.placesOn(t, pageDate, subgroup),
                         onOpen = onOpen,
+                        fresh = fresh,
+                        onFreshShown = vm::freshShown,
                     )
                 }
             }
@@ -437,12 +452,30 @@ private fun Planner(
 }
 
 @Composable
-private fun DayPage(date: LocalDate, slots: List<Slot>, places: List<DayPlace>, onOpen: (Lesson, LocalDate) -> Unit) {
+private fun DayPage(
+    date: LocalDate,
+    slots: List<Slot>,
+    places: List<DayPlace>,
+    onOpen: (Lesson, LocalDate) -> Unit,
+    fresh: Set<String> = emptySet(),
+    onFreshShown: (String) -> Unit = {},
+) {
     val clock = rememberClock()
     val isToday = date == today()
     val next = if (isToday) slots.firstOrNull { it.start.isAfter(clock) } else null
+    val list = rememberLazyListState()
+    // Today opens on the lesson under way (or the next one), not on the morning's first: one
+    // look tells where to go now. Once per page, so a scroll back up stays where it is.
+    LaunchedEffect(isToday) {
+        if (!isToday) return@LaunchedEffect
+        val now = slots.indexOfFirst { clock.isBefore(it.end) }
+        if (now <= 0) return@LaunchedEffect
+        val before = (if (places.isNotEmpty()) 1 else 0) + slots.take(now).sumOf { it.lessons.size }
+        list.scrollToItem(before)
+    }
     ContentColumn {
         LazyColumn(
+            state = list,
             contentPadding = PaddingValues(start = 16.dp, end = 16.dp, top = 16.dp, bottom = 24.dp + navBarPadding()),
             verticalArrangement = Arrangement.spacedBy(12.dp),
             modifier = Modifier.fillMaxSize(),
@@ -472,7 +505,11 @@ private fun DayPage(date: LocalDate, slots: List<Slot>, places: List<DayPlace>,
                             date = date,
                             status = status,
                             running = running,
+                            progress = if (running) Duration.between(slot.start, clock).toSeconds().toFloat() /
+                                Duration.between(slot.start, slot.end).toSeconds().coerceAtLeast(1) else null,
                             onClick = { onOpen(lesson, date) },
+                            fresh = lesson.key in fresh,
+                            onFreshShown = { onFreshShown(lesson.key) },
                         )
                     }
                 }
@@ -491,7 +528,12 @@ fun LessonCard(
     date: LocalDate? = null,
     status: String? = null,
     running: Boolean = false,
+    /** How far the lesson under way has gone, 0..1: a line runs round the card. */
+    progress: Float? = null,
     onClick: (() -> Unit)?,
+    /** Just added or changed by a republished document: the card glows twice, then [onFreshShown]. */
+    fresh: Boolean = false,
+    onFreshShown: () -> Unit = {},
 ) {
     val color = subjectColor(lesson.subject)
     val show = LocalDisplay.current
@@ -509,7 +551,7 @@ fun LessonCard(
                         color = if (running) color.onSoft else color.onSoft.copy(alpha = 0.12f),
                         contentColor = if (running) color.soft else color.onSoft,
                     ) {
-                        Text(it, style = MaterialTheme.typography.labelLarge, modifier = Modifier.padding(horizontal = 8.dp, vertical = 3.dp))
+                        RollingText(it, style = MaterialTheme.typography.labelLarge, modifier = Modifier.padding(horizontal = 8.dp, vertical = 3.dp))
                     }
                 }
             }
@@ -527,6 +569,13 @@ fun LessonCard(
                 lesson.type.ifEmpty { null }?.takeIf { session == null },
                 if (lesson.variant != "all") (if (lesson.variant == "upper") "белые недели" else "зелёные недели") else null,
                 if (lesson.groups.size > 1) "общее занятие" else null,
+                // German or French: a part of the group has this one, the rest the other.
+                if (lesson.option != null) "на выбор" else null,
+                when (lesson.audience) {
+                    "foreign" -> "для иностранных студентов"
+                    "local" -> "кроме иностранных студентов"
+                    else -> null
+                },
             )
             val mark = date?.let { LocalMarks.current.forLesson(lesson.subject, it, lesson.start) }
             if (tags.isNotEmpty() || lesson.uncertain || mark != null) FlowRow(
@@ -544,7 +593,26 @@ fun LessonCard(
             if (date != null) NotesHint(LocalNotes.current.forLesson(lesson.subject, date, lesson.start), color.onSoft)
         }
     }
+    // A tapped card grows into its details page (Morph.kt).
+    val glow = remember { androidx.compose.animation.core.Animatable(0f) }
+    val reduced = rememberReducedMotion()
+    LaunchedEffect(fresh) {
+        if (!fresh) return@LaunchedEffect
+        if (!reduced) repeat(2) {
+            glow.animateTo(1f, tween(350, easing = EmphasizedDecelerate))
+            glow.animateTo(0f, tween(450))
+        }
+        onFreshShown()
+    }
+    // The fill itself turns tertiary and back, so the text stays as crisp as on any card.
+    val highlight = MaterialTheme.colorScheme.tertiaryContainer
+    val fill = if (glow.value > 0f) androidx.compose.ui.graphics.lerp(color.soft, highlight, glow.value) else color.soft
+    val origin = if (onClick != null) Modifier.morphOrigin("card|$date|${lesson.key}|${lesson.start}", color.soft, 16.dp) else Modifier
+    // The line round a running card grows a little every half minute, never jumps.
+    val shown by androidx.compose.animation.core.animateFloatAsState(progress ?: 0f, tween(1000), label = "progress")
+    val live = if (running && progress != null) Modifier.progressBorder(shown, color.onSoft, 16.dp) else Modifier
     val border = when {
+        running && progress != null -> null
         running -> BorderStroke(2.dp, color.onSoft)
         session != null -> BorderStroke(2.dp, session.outline())
         else -> null
@@ -552,10 +620,10 @@ fun LessonCard(
     if (onClick != null) Surface(
         onClick = onClick,
         shape = MaterialTheme.shapes.large,
-        color = color.soft,
+        color = fill,
         contentColor = color.onSoft,
         border = border,
-        modifier = Modifier.fillMaxWidth(),
+        modifier = Modifier.fillMaxWidth().then(origin).then(live),
         content = content,
     ) else Surface(
         shape = MaterialTheme.shapes.large,
@@ -627,6 +695,9 @@ internal fun LessonDetails(
     onClose: () -> Unit = {},
 ) {
     val bell = bells.firstOrNull { it.start == lesson.start }
+    // Hiding closes the sheet, so its "Вернуть" goes to the screen; tasks deleted here, to the sheet.
+    val screenUndo = LocalUndo.current
+    UndoArea(bottom = false) {
     Column(
         Modifier
             .verticalScroll(rememberScrollState())
@@ -668,7 +739,11 @@ internal fun LessonDetails(
             Text(lesson.raw, style = MaterialTheme.typography.bodyLarge, modifier = Modifier.padding(16.dp).fillMaxWidth())
         }
         if (vm != null) {
-            OutlinedButton(onClick = { vm.setHidden(lesson.hideKey, true); onClose() }) {
+            OutlinedButton(onClick = {
+                vm.setHidden(lesson.hideKey, true)
+                onClose()
+                screenUndo?.offer("Скрыто: «${lesson.subject}»", onUndo = { vm.setHidden(lesson.hideKey, false) })
+            }) {
                 Icon(Icons.Rounded.VisibilityOff, contentDescription = null, modifier = Modifier.size(18.dp))
                 Spacer(Modifier.width(8.dp))
                 Text("Скрыть такие занятия")
@@ -681,6 +756,7 @@ internal fun LessonDetails(
             )
         }
     }
+    }
 }
 
 @Composable
@@ -710,7 +786,7 @@ private fun WordRows(t: Timetable, subgroup: String?, hidden: Set<String>, onOpe
                 Heading(dayName(day.day), style = MaterialTheme.typography.headlineSmallEmphasized)
             }
             val lessons = day.lessons.filter { subgroup == null || it.subgroup == null || it.subgroup == subgroup }
-                .filter { it.hideKey !in hidden }
+                .filter { !it.hiddenIn(hidden) }
             val places = if (lessons.isEmpty()) emptyList() else day.places.forSubgroup(subgroup)
             if (places.isNotEmpty()) item(key = "p${day.day}") { DayPlaces(places) }
             items(lessons, key = { "${day.day}-${it.key}" }) { lesson ->
@@ -828,3 +904,31 @@ private val FACULTIES = mapOf(
 )
 
 fun facultyShort(name: String): String? = name.takeIf { it.isNotEmpty() }?.let { FACULTIES[it] ?: it }
+
+/**
+ * Opens a lesson's details as a page growing out of the card that was tapped (Morph.kt); from
+ * anywhere else (the week grid of a narrow column, a notification) it grows from the middle.
+ */
+@Composable
+fun rememberLessonOpener(vm: MainViewModel): (Lesson, LocalDate?) -> Unit {
+    val morph = LocalMorph.current
+    return remember(morph, vm) {
+        { lesson, date -> morph?.open(MorphKind.Page) { close -> LessonPage(lesson, date, vm, close) } }
+    }
+}
+
+/** The details as a page: a close button over them; full screen on a phone, a panel on a tablet. */
+@Composable
+private fun LessonPage(lesson: Lesson, date: LocalDate?, vm: MainViewModel, close: () -> Unit) {
+    val timetable by vm.timetable.collectAsStateWithLifecycle()
+    BoxWithConstraints(Modifier.fillMaxSize()) {
+        // The phone's page covers the bars; a tablet's panel sits inside them.
+        val insets = if (maxWidth >= 600.dp) Modifier else Modifier.windowInsetsPadding(WindowInsets.systemBars)
+        Column(Modifier.fillMaxSize().then(insets)) {
+            Row(verticalAlignment = Alignment.CenterVertically, modifier = Modifier.padding(start = 8.dp, top = 4.dp)) {
+                IconButton(onClick = close) { Icon(Icons.Rounded.Close, contentDescription = "Закрыть") }
+            }
+            LessonDetails(lesson, timetable?.bells.orEmpty(), date, vm, onClose = close)
+        }
+    }
+}

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/SearchScreen.kt

@@ -51,7 +51,6 @@ import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.ExperimentalMaterial3ExpressiveApi
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
-import androidx.compose.material3.LoadingIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
@@ -243,7 +242,7 @@ fun SearchScreen(vm: MainViewModel, nav: AppNav) {
         ) {
             if (target != null) {
                 val d = day
-                if (loading && d == null) item { Row(Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.Center) { LoadingIndicator() } }
+                if (loading && d == null) item { LessonsSkeleton(3) }
                 if (d != null) {
                     if (d.lessons.isEmpty()) item {
                         Box(Modifier.fillParentMaxHeight(0.8f).fillMaxWidth(), contentAlignment = Alignment.Center) {

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/SettingsScreen.kt

@@ -2,6 +2,8 @@
 
 package org.xtimms.psu.schedule.ui
 
+import androidx.compose.ui.platform.LocalHapticFeedback
+import androidx.compose.ui.hapticfeedback.HapticFeedbackType
 import androidx.compose.ui.draw.clip
 import androidx.compose.foundation.selection.toggleable
 import androidx.compose.ui.semantics.Role
@@ -43,6 +45,8 @@ import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import org.xtimms.psu.schedule.BuildConfig
 import org.xtimms.psu.schedule.data.ThemeMode
+import org.xtimms.psu.schedule.data.OPTION_PREFIX
+import org.xtimms.psu.schedule.data.AUDIENCE_PREFIX
 import org.xtimms.psu.schedule.notify.Reminders
 
 @OptIn(ExperimentalMaterial3Api::class)
@@ -120,9 +124,12 @@ fun SettingsScreen(vm: MainViewModel, onBack: () -> Unit) {
                 SwitchRow("Пометки из Word", "Например, «3-13н.» — даты по ним уже рассчитаны", d.notes) {
                     vm.setDisplay(d.copy(notes = it))
                 }
-                if (s.hidden.isNotEmpty()) {
+                // The options of a choice the student did not take, and the lessons for foreign
+                // students or the others, are set in "Группы", not here.
+                val hidden = s.hidden.filterNot { it.startsWith(OPTION_PREFIX) || it.startsWith(AUDIENCE_PREFIX) }
+                if (hidden.isNotEmpty()) {
                     Text("Скрытые занятия", style = MaterialTheme.typography.labelLarge, color = MaterialTheme.colorScheme.onSurfaceVariant)
-                    s.hidden.sorted().forEach { key ->
+                    hidden.sorted().forEach { key ->
                         val (subject, type) = key.split("|", limit = 2).let { it[0] to it.getOrElse(1) { "" } }
                         Row(verticalAlignment = Alignment.CenterVertically) {
                             Text(
@@ -283,7 +290,12 @@ private fun Section(title: String, content: @Composable () -> Unit) {
 }
 
 @Composable
-private fun SwitchRow(title: String, text: String, checked: Boolean, onChange: (Boolean) -> Unit) {
+private fun SwitchRow(title: String, text: String, checked: Boolean, change: (Boolean) -> Unit) {
+    val haptic = LocalHapticFeedback.current
+    val onChange: (Boolean) -> Unit = { on ->
+        haptic.performHapticFeedback(if (on) HapticFeedbackType.ToggleOn else HapticFeedbackType.ToggleOff)
+        change(on)
+    }
     // The whole row is the touch target, not only the switch.
     Row(
         verticalAlignment = Alignment.CenterVertically,

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Skeleton.kt

@@ -0,0 +1,195 @@
+package org.xtimms.psu.schedule.ui
+
+import androidx.compose.animation.core.LinearEasing
+import androidx.compose.animation.core.animateFloat
+import androidx.compose.animation.core.infiniteRepeatable
+import androidx.compose.animation.core.rememberInfiniteTransition
+import androidx.compose.animation.core.tween
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.layout.widthIn
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.draw.drawBehind
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.graphics.Brush
+import androidx.compose.ui.graphics.Shape
+import androidx.compose.ui.semantics.LiveRegionMode
+import androidx.compose.ui.semantics.clearAndSetSemantics
+import androidx.compose.ui.semantics.contentDescription
+import androidx.compose.ui.semantics.liveRegion
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import org.xtimms.psu.schedule.ui.theme.card
+
+// Placeholders in the shape of what is loading: the first timetable of a group, a teacher's day,
+// the catalog. The screen keeps its layout instead of a lone spinner in the middle.
+
+/**
+ * A soft light sweeping across a placeholder, once every 1.2 s. With animations turned off in
+ * the system it stays a plain tone.
+ */
+@Composable
+private fun Modifier.shimmer(): Modifier {
+    val ink = MaterialTheme.colorScheme.onSurface
+    val base = ink.copy(alpha = 0.08f)
+    val light = ink.copy(alpha = 0.15f)
+    if (rememberReducedMotion()) return background(base)
+    val sweep = rememberInfiniteTransition(label = "shimmer")
+    val x by sweep.animateFloat(-1f, 2f, infiniteRepeatable(tween(1200, easing = LinearEasing)), label = "x")
+    return drawBehind {
+        val w = size.width.coerceAtLeast(1f)
+        drawRect(Brush.linearGradient(listOf(base, light, base), start = Offset(w * (x - 0.5f), 0f), end = Offset(w * (x + 0.5f), size.height)))
+    }
+}
+
+/** One placeholder bar or shape. */
+@Composable
+private fun Bone(modifier: Modifier, shape: Shape = MaterialTheme.shapes.small) {
+    Box(modifier.clip(shape).shimmer())
+}
+
+/** Screen readers hear "Загрузка" once, not every bar. */
+private fun Modifier.loading(): Modifier = clearAndSetSemantics {
+    contentDescription = "Загрузка"
+    liveRegion = LiveRegionMode.Polite
+}
+
+/** A lesson card: subject, time, room and teacher. */
+@Composable
+fun LessonCardSkeleton(modifier: Modifier = Modifier) {
+    Surface(shape = MaterialTheme.shapes.large, color = MaterialTheme.colorScheme.surfaceContainerHigh, modifier = modifier.fillMaxWidth()) {
+        Column(Modifier.padding(horizontal = 20.dp, vertical = 16.dp), verticalArrangement = Arrangement.spacedBy(10.dp)) {
+            Bone(Modifier.fillMaxWidth(0.72f).height(20.dp))
+            Bone(Modifier.fillMaxWidth(0.4f).height(16.dp))
+            Row(horizontalArrangement = Arrangement.spacedBy(16.dp)) {
+                Bone(Modifier.width(72.dp).height(14.dp))
+                Bone(Modifier.width(112.dp).height(14.dp))
+            }
+        }
+    }
+}
+
+/** A few lesson cards, for a day that is loading. */
+@Composable
+fun LessonsSkeleton(count: Int = 3, modifier: Modifier = Modifier) {
+    Column(modifier.loading(), verticalArrangement = Arrangement.spacedBy(12.dp)) {
+        repeat(count) { LessonCardSkeleton() }
+    }
+}
+
+/** The schedule: the week's day strip, then the day's cards. */
+@Composable
+fun ScheduleSkeleton() {
+    Column(Modifier.fillMaxSize().loading()) {
+        Row(Modifier.fillMaxWidth().padding(horizontal = 8.dp, vertical = 8.dp)) {
+            repeat(7) {
+                Column(Modifier.weight(1f), horizontalAlignment = Alignment.CenterHorizontally) {
+                    Bone(Modifier.width(18.dp).height(12.dp))
+                    Spacer(Modifier.height(8.dp))
+                    Bone(Modifier.size(36.dp), CircleShape)
+                }
+            }
+        }
+        ContentColumn {
+            LessonsSkeleton(4, Modifier.padding(16.dp))
+        }
+    }
+}
+
+/** The overview: the week card, "Сегодня" and the next lessons. */
+@Composable
+fun OverviewSkeleton() {
+    ContentColumn {
+        Column(
+            Modifier.fillMaxSize().padding(horizontal = 16.dp, vertical = 8.dp).loading(),
+            verticalArrangement = Arrangement.spacedBy(16.dp),
+        ) {
+            SkeletonCard {
+                Bone(Modifier.width(120.dp).height(20.dp))
+                Bone(Modifier.fillMaxWidth(0.7f).height(26.dp))
+                Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                    repeat(6) { Bone(Modifier.weight(1f).height(52.dp), MaterialTheme.shapes.medium) }
+                }
+            }
+            Bone(Modifier.width(140.dp).height(28.dp).padding(top = 4.dp))
+            SkeletonCard {
+                Bone(Modifier.width(180.dp).height(20.dp))
+                repeat(3) {
+                    Row(verticalAlignment = Alignment.CenterVertically) {
+                        Bone(Modifier.size(12.dp), CircleShape)
+                        Spacer(Modifier.width(16.dp))
+                        Column(verticalArrangement = Arrangement.spacedBy(6.dp)) {
+                            Bone(Modifier.widthIn(max = 260.dp).fillMaxWidth(0.8f).height(18.dp))
+                            Bone(Modifier.width(120.dp).height(14.dp))
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+/** Subjects: a card per subject with its badge, name and next lesson. */
+@Composable
+fun SubjectsSkeleton() {
+    ContentColumn {
+        Column(
+            Modifier.fillMaxSize().padding(16.dp).loading(),
+            verticalArrangement = Arrangement.spacedBy(12.dp),
+        ) {
+            repeat(5) {
+                SkeletonCard {
+                    Row(verticalAlignment = Alignment.CenterVertically) {
+                        Bone(Modifier.size(48.dp), CircleShape)
+                        Spacer(Modifier.width(16.dp))
+                        Column(Modifier.weight(1f), verticalArrangement = Arrangement.spacedBy(8.dp)) {
+                            Bone(Modifier.fillMaxWidth(0.75f).height(18.dp))
+                            Bone(Modifier.fillMaxWidth(0.5f).height(14.dp))
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+/** Rows of a list with an avatar: the groups of the catalog. */
+@Composable
+fun RowsSkeleton(count: Int = 6, avatar: Dp = 40.dp) {
+    Column(Modifier.fillMaxWidth().loading(), verticalArrangement = Arrangement.spacedBy(18.dp)) {
+        repeat(count) {
+            Row(verticalAlignment = Alignment.CenterVertically, modifier = Modifier.padding(horizontal = 4.dp)) {
+                Bone(Modifier.size(avatar), CircleShape)
+                Spacer(Modifier.width(16.dp))
+                Column(verticalArrangement = Arrangement.spacedBy(6.dp)) {
+                    Bone(Modifier.width(120.dp).height(16.dp))
+                    Bone(Modifier.width(180.dp).height(13.dp))
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun SkeletonCard(content: @Composable () -> Unit) {
+    Surface(shape = MaterialTheme.shapes.extraLarge, color = MaterialTheme.colorScheme.card, modifier = Modifier.fillMaxWidth()) {
+        Column(Modifier.padding(20.dp), verticalArrangement = Arrangement.spacedBy(14.dp)) { content() }
+    }
+}

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/SubjectsScreen.kt

@@ -41,7 +41,6 @@ import androidx.compose.material.icons.rounded.Person
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.ExperimentalMaterial3ExpressiveApi
 import androidx.compose.material3.Icon
-import androidx.compose.material3.LoadingIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.ModalBottomSheet
 import androidx.compose.material3.Surface
@@ -128,7 +127,7 @@ fun SubjectsScreen(vm: MainViewModel, nav: AppNav) {
         )
         val t = timetable
         when {
-            t == null && status.loading -> Box(Modifier.fillMaxSize(), contentAlignment = Alignment.Center) { LoadingIndicator() }
+            t == null && status.loading -> SubjectsSkeleton()
             t == null -> CenteredEmpty {
                 Empty("Предметов пока нет", "Выберите группу — предметы появятся из её расписания.", icon = Icons.AutoMirrored.Rounded.MenuBook, action = "Выбрать группу" to nav.openGroups)
             }
@@ -328,6 +327,8 @@ private fun Fact(icon: ImageVector, text: String, strong: Boolean = false) {
 @Composable
 private fun SubjectDetails(s: SubjectSummary, vm: MainViewModel) {
     val color = subjectColor(s.name)
+    // A task deleted in the sheet offers "Вернуть" in the sheet itself.
+    UndoArea(bottom = false) {
     Column(
         Modifier
             .verticalScroll(rememberScrollState())
@@ -372,6 +373,7 @@ private fun SubjectDetails(s: SubjectSummary, vm: MainViewModel) {
             }
         }
     }
+    }
 }
 
 @Composable
@@ -389,6 +391,7 @@ private fun DetailLine(icon: ImageVector, label: String, value: String) {
 /** Every task and note of the subject, open ones first, with a quick add for the next lesson. */
 @Composable
 private fun SubjectNotes(s: SubjectSummary, vm: MainViewModel) {
+    val undo = LocalUndo.current
     val all by vm.notes.collectAsStateWithLifecycle()
     val group = vm.currentGroupKey() ?: return
     val notes = all.filter { subjectKey(it.subject) == subjectKey(s.name) }
@@ -414,7 +417,7 @@ private fun SubjectNotes(s: SubjectSummary, vm: MainViewModel) {
         editing = editing,
         groupKey = editing?.group ?: group,
         onSave = { vm.saveNote(it); adding = false; editing = null },
-        onDelete = { vm.deleteNote(it.id); editing = null },
+        onDelete = { vm.deleteNote(it.id, undo); editing = null },
         onDismiss = { adding = false; editing = null },
     )
 }

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Tabletop.kt

@@ -131,7 +131,7 @@ private fun StandLesson(slot: Slot, clock: LocalTime, isToday: Boolean, onOpen:
         shape = MaterialTheme.shapes.extraLarge,
         color = color.soft,
         contentColor = color.onSoft,
-        modifier = modifier,
+        modifier = modifier.morphOrigin("stand|${slot.date}|${lesson.key}|${lesson.start}", color.soft, 28.dp),
     ) {
         Column(Modifier.padding(24.dp), verticalArrangement = Arrangement.spacedBy(8.dp)) {
             Row(verticalAlignment = Alignment.CenterVertically) {
@@ -147,7 +147,7 @@ private fun StandLesson(slot: Slot, clock: LocalTime, isToday: Boolean, onOpen:
                         color = if (running) color.container else MaterialTheme.colorScheme.surface,
                         contentColor = if (running) color.content else MaterialTheme.colorScheme.onSurface,
                     ) {
-                        Text(
+                        RollingText(
                             if (running) "Идёт · ещё ${minutesLabel(minutes)}" else "Через ${minutesLabel(minutes)}",
                             style = MaterialTheme.typography.labelLarge,
                             modifier = Modifier.padding(horizontal = 12.dp, vertical = 6.dp),

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/Undo.kt

@@ -0,0 +1,67 @@
+package org.xtimms.psu.schedule.ui
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.BoxScope
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.navigationBarsPadding
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.widthIn
+import androidx.compose.material3.SnackbarDuration
+import androidx.compose.material3.SnackbarHost
+import androidx.compose.material3.SnackbarHostState
+import androidx.compose.material3.SnackbarResult
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.staticCompositionLocalOf
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.launch
+
+/**
+ * "Задание удалено · Вернуть": actions that are easy to regret are done at once and offered back
+ * in a snackbar instead of asking first. [offer] shows it in the nearest host — the screen's, or
+ * a bottom sheet's own, since a sheet covers the screen's.
+ */
+class UndoHost(val state: SnackbarHostState, private val scope: CoroutineScope) {
+    /** [onGone] runs when the chance to undo has passed: the snackbar timed out or was replaced. */
+    fun offer(message: String, onUndo: () -> Unit, onGone: () -> Unit = {}) {
+        scope.launch {
+            // A new action replaces the previous offer, which then cannot be undone any more.
+            state.currentSnackbarData?.dismiss()
+            var undone = false
+            try {
+                undone = state.showSnackbar(message, actionLabel = "Вернуть", duration = SnackbarDuration.Long) ==
+                    SnackbarResult.ActionPerformed
+                if (undone) onUndo()
+            } finally {
+                if (!undone) onGone()
+            }
+        }
+    }
+}
+
+val LocalUndo = staticCompositionLocalOf<UndoHost?> { null }
+
+/** A host for [content] and its snackbar at the bottom: the app's screens, or a sheet. */
+@Composable
+fun UndoArea(modifier: Modifier = Modifier, bottom: Boolean = true, content: @Composable BoxScope.() -> Unit) {
+    val state = remember { SnackbarHostState() }
+    val scope = rememberCoroutineScope()
+    val host = remember(state, scope) { UndoHost(state, scope) }
+    Box(modifier) {
+        CompositionLocalProvider(LocalUndo provides host) { content() }
+        SnackbarHost(
+            state,
+            Modifier
+                .align(Alignment.BottomCenter)
+                .then(if (bottom) Modifier.navigationBarsPadding() else Modifier)
+                .padding(horizontal = 16.dp, vertical = 12.dp)
+                .widthIn(max = 560.dp)
+                .fillMaxWidth(),
+        )
+    }
+}

android/app/src/main/kotlin/org/xtimms/psu/schedule/ui/WeekGrid.kt

@@ -2,6 +2,8 @@
 
 package org.xtimms.psu.schedule.ui
 
+import androidx.compose.runtime.getValue
+import androidx.compose.animation.core.tween
 import androidx.compose.ui.text.intl.LocaleList
 import androidx.compose.ui.text.style.Hyphens
 import androidx.compose.ui.text.style.LineBreak
@@ -165,7 +167,8 @@ fun WeekGrid(
                         }
                     }
                     if (d == today() && clock.hour in first until last) {
-                        val y = top(clock)
+                        // The "now" line slides down with the clock instead of hopping every half minute.
+                        val y by androidx.compose.animation.core.animateDpAsState(top(clock), tween(1000), label = "now")
                         Box(Modifier.offset(y = y - 1.dp).fillMaxWidth().height(2.dp).background(MaterialTheme.colorScheme.primary))
                         Box(Modifier.offset(x = (-5).dp, y = y - 5.dp).size(10.dp).background(MaterialTheme.colorScheme.primary, CircleShape))
                     }
@@ -179,6 +182,7 @@ fun WeekGrid(
 private fun LessonBlock(lesson: Lesson, slot: Slot, wide: Boolean, notes: Int, onClick: () -> Unit, modifier: Modifier) {
     val color = subjectColor(lesson.subject)
     val session = lesson.session
+    val origin = Modifier.morphOrigin("grid|${slot.date}|${lesson.key}|${lesson.start}", color.container, 8.dp)
     val rooms = lesson.rooms.joinToString(", ").takeIf { LocalDisplay.current.rooms }.orEmpty()
     // A narrow column keeps the room whole: the day's town is under its date.
     val room = when {
@@ -192,7 +196,7 @@ private fun LessonBlock(lesson: Lesson, slot: Slot, wide: Boolean, notes: Int, o
         color = color.container,
         contentColor = color.content,
         border = session?.let { androidx.compose.foundation.BorderStroke(2.dp, it.outline()) },
-        modifier = modifier.semantics {
+        modifier = modifier.then(origin).semantics {
             contentDescription = "${lesson.subject}, ${slot.start}–${slot.end}" +
                 (if (room.isNotEmpty()) ", ауд. $room" else "") + (lesson.type.takeIf { it.isNotEmpty() }?.let { ", $it" } ?: "") +
                 (if (notes > 0) ", заданий и заметок: $notes" else "")

android/app/src/main/kotlin/org/xtimms/psu/schedule/widget/WeekWidget.kt

@@ -0,0 +1,246 @@
+package org.xtimms.psu.schedule.widget
+
+import android.content.Context
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import androidx.glance.ColorFilter
+import androidx.glance.GlanceId
+import androidx.glance.GlanceModifier
+import androidx.glance.GlanceTheme
+import androidx.glance.Image
+import androidx.glance.ImageProvider
+import androidx.glance.LocalSize
+import androidx.glance.appwidget.action.actionStartActivity
+import androidx.glance.action.clickable
+import androidx.glance.appwidget.GlanceAppWidget
+import androidx.glance.appwidget.GlanceAppWidgetReceiver
+import androidx.glance.appwidget.SizeMode
+import androidx.glance.appwidget.provideContent
+import androidx.glance.layout.Alignment
+import androidx.glance.layout.Column
+import androidx.glance.layout.Row
+import androidx.glance.layout.Spacer
+import androidx.glance.layout.fillMaxHeight
+import androidx.glance.layout.fillMaxSize
+import androidx.glance.layout.fillMaxWidth
+import androidx.glance.layout.height
+import androidx.glance.layout.padding
+import androidx.glance.layout.size
+import androidx.glance.layout.width
+import androidx.glance.text.FontWeight
+import androidx.glance.text.Text
+import androidx.glance.text.TextAlign
+import androidx.glance.text.TextStyle
+import org.xtimms.psu.schedule.Launch
+import org.xtimms.psu.schedule.R
+import org.xtimms.psu.schedule.app
+import org.xtimms.psu.schedule.data.Week
+import org.xtimms.psu.schedule.ui.theme.WeekColors
+import androidx.glance.color.ColorProvider
+import org.xtimms.psu.schedule.data.longLabel
+import org.xtimms.psu.schedule.data.monday
+import org.xtimms.psu.schedule.data.plural
+import org.xtimms.psu.schedule.data.shortWeekday
+import org.xtimms.psu.schedule.data.today
+import org.xtimms.psu.schedule.ui.abbreviate
+import java.time.LocalDate
+
+/** A day of the week as the widget shows it. */
+private data class WeekDay(
+    val date: LocalDate,
+    /** Abbreviations of the day's lessons, one per start time: "ФГА", "ЯПОА / ПУПР". */
+    val lessons: List<String>,
+    /** "Полоцк" when the day is in another town. */
+    val place: String?,
+    val moved: Boolean,
+)
+
+private data class WeekState(
+    val group: String?,
+    val week: Week?,
+    val monday: LocalDate,
+    val days: List<WeekDay>,
+    val dynamic: Boolean,
+)
+
+private suspend fun state(context: Context): WeekState? {
+    val app = context.app
+    val t = app.repository.timetable.value ?: return null
+    val s = app.settings.now()
+    // On Sunday the coming week is the useful one, as in the overview's week pane.
+    val monday = (if (today().dayOfWeek.value == 7) today().plusDays(1) else today()).monday()
+    val all = (0..6L).map { monday.plusDays(it) }.map { d ->
+        val lessons = app.repository.lessonsOn(t, d, s.subgroup, s.hidden)
+        WeekDay(
+            date = d,
+            lessons = lessons.groupBy { it.start }.toSortedMap().values.map { slot -> slot.joinToString(" / ") { abbreviate(it.subject) } },
+            place = app.repository.placesOn(t, d, s.subgroup, s.hidden).firstOrNull()?.place,
+            moved = lessons.any { it.roomMoved },
+        )
+    }
+    return WeekState(
+        group = t.group,
+        week = t.days.firstOrNull { it.date == monday.toString() }?.week,
+        monday = monday,
+        // Sunday only takes a column when something happens on it.
+        days = all.filter { it.date.dayOfWeek.value < 7 || it.lessons.isNotEmpty() },
+        dynamic = s.dynamicColor,
+    )
+}
+
+/**
+ * The week at a glance (4×2 and larger): each day with its number of lessons, a city mark on
+ * days in another town and a swap mark on days with a room move; taller, the lessons too. A day
+ * opens in the app.
+ */
+class WeekWidget : GlanceAppWidget() {
+    override val sizeMode = SizeMode.Exact
+
+    override suspend fun provideGlance(context: Context, id: GlanceId) {
+        val data = state(context)
+        val dynamic = data?.dynamic ?: context.app.settings.now().dynamicColor
+        provideContent { WidgetTheme(dynamic) { Content(context, data) } }
+    }
+
+    @Composable
+    private fun Content(context: Context, data: WeekState?) {
+        Column(
+            modifier = GlanceModifier
+                .fillMaxSize()
+                .roundedBackground(GlanceTheme.colors.widgetBackground, 28.dp)
+                .padding(12.dp),
+        ) {
+            if (data == null) {
+                Text(
+                    "Откройте приложение и выберите группу",
+                    style = TextStyle(color = GlanceTheme.colors.onSurface, fontSize = 15.sp),
+                    modifier = GlanceModifier.padding(4.dp).clickable(actionStartActivity(Launch.intent(context, "today"))),
+                )
+                return@Column
+            }
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                modifier = GlanceModifier.fillMaxWidth().padding(start = 4.dp, end = 4.dp, bottom = 8.dp)
+                    .clickable(actionStartActivity(Launch.intent(context, "week"))),
+            ) {
+                Text(
+                    data.week?.let { "Неделя ${it.n}" } ?: "Неделя",
+                    style = TextStyle(color = GlanceTheme.colors.primary, fontWeight = FontWeight.Bold, fontSize = 15.sp),
+                )
+                data.week?.let { w ->
+                    Spacer(GlanceModifier.width(8.dp))
+                    // The university's week colours, as on the app's week mark.
+                    Text(
+                        if (w.white) "белая" else "зелёная",
+                        style = TextStyle(
+                            color = ColorProvider(day = WeekColors.content(w.white, false), night = WeekColors.content(w.white, true)),
+                            fontSize = 11.sp,
+                            fontWeight = FontWeight.Medium,
+                        ),
+                        modifier = GlanceModifier
+                            .roundedBackground(
+                                if (w.white) GlanceTheme.colors.surfaceVariant
+                                else ColorProvider(day = WeekColors.container(false, false), night = WeekColors.container(false, true)),
+                                8.dp,
+                            )
+                            .padding(horizontal = 6.dp, vertical = 1.dp),
+                    )
+                }
+                Spacer(GlanceModifier.defaultWeight())
+                Text(data.group.orEmpty(), maxLines = 1, style = TextStyle(color = GlanceTheme.colors.onSurfaceVariant, fontSize = 12.sp))
+            }
+            // Header about 40dp, padding 24dp; a lesson line about 14dp below the day's head.
+            val height = LocalSize.current.height
+            val lines = ((height - 40.dp - 24.dp - 62.dp) / 14.dp).toInt().coerceIn(0, 6)
+            val summary = summary(data.days)
+            val roomForSummary = summary != null && height >= 150.dp
+            // Glance keeps at most ten children in a row: the gaps are the tiles' padding, not spacers.
+            Row(modifier = GlanceModifier.fillMaxWidth().defaultWeight()) {
+                data.days.forEachIndexed { index, day ->
+                    DayTile(
+                        context, day, lines - if (roomForSummary) 1 else 0,
+                        GlanceModifier.defaultWeight().fillMaxHeight()
+                            .padding(start = if (index > 0) 2.dp else 0.dp, end = if (index < data.days.lastIndex) 2.dp else 0.dp),
+                    )
+                }
+            }
+            if (roomForSummary) Text(
+                summary!!,
+                maxLines = 1,
+                style = TextStyle(color = GlanceTheme.colors.onSurfaceVariant, fontSize = 11.sp),
+                modifier = GlanceModifier.padding(start = 4.dp, top = 6.dp),
+            )
+        }
+    }
+
+    @Composable
+    private fun DayTile(context: Context, day: WeekDay, lines: Int, modifier: GlanceModifier) {
+        val isToday = day.date == today()
+        val past = day.date < today()
+        val count = day.lessons.size
+        val (fill, ink) = when {
+            isToday -> GlanceTheme.colors.primary to GlanceTheme.colors.onPrimary
+            count > 0 -> GlanceTheme.colors.secondaryContainer to GlanceTheme.colors.onSecondaryContainer
+            else -> GlanceTheme.colors.surfaceVariant to GlanceTheme.colors.onSurfaceVariant
+        }
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            modifier = modifier
+                .roundedBackground(fill, 16.dp)
+                .padding(vertical = 6.dp, horizontal = 2.dp)
+                .clickable(actionStartActivity(Launch.intent(context, "day", day.date))),
+        ) {
+            Text(day.date.shortWeekday(), style = TextStyle(color = ink, fontSize = 11.sp, textAlign = TextAlign.Center))
+            Text(
+                "${day.date.dayOfMonth}",
+                style = TextStyle(color = ink, fontSize = 17.sp, fontWeight = FontWeight.Bold, textAlign = TextAlign.Center),
+            )
+            Text(
+                if (count == 0) "—" else "$count ${plural(count, "пара", "пары", "пар")}",
+                maxLines = 1,
+                style = TextStyle(
+                    color = ink,
+                    fontSize = 10.sp,
+                    textAlign = TextAlign.Center,
+                    fontWeight = if (past) FontWeight.Normal else FontWeight.Medium,
+                ),
+            )
+            if (day.place != null || day.moved) Row(modifier = GlanceModifier.padding(top = 2.dp)) {
+                if (day.place != null) Image(
+                    ImageProvider(R.drawable.ic_widget_city),
+                    contentDescription = "Занятия: ${day.place}",
+                    colorFilter = ColorFilter.tint(if (isToday) ink else GlanceTheme.colors.tertiary),
+                    modifier = GlanceModifier.size(14.dp),
+                )
+                if (day.moved) Image(
+                    ImageProvider(R.drawable.ic_widget_move),
+                    contentDescription = "Перенос аудитории",
+                    colorFilter = ColorFilter.tint(if (isToday) ink else GlanceTheme.colors.error),
+                    modifier = GlanceModifier.size(14.dp).padding(start = if (day.place != null) 2.dp else 0.dp),
+                )
+            }
+            // Taller: the lessons themselves, as the week grid abbreviates them.
+            if (lines > 0) {
+                Spacer(GlanceModifier.height(2.dp))
+                day.lessons.take(lines).forEach {
+                    Text(it, maxLines = 1, style = TextStyle(color = ink, fontSize = 10.sp, textAlign = TextAlign.Center))
+                }
+                if (day.lessons.size > lines) Text("…", style = TextStyle(color = ink, fontSize = 10.sp))
+            }
+        }
+    }
+
+    /** "Полоцк: вт, пт · перенос: пн, чт", or null for an ordinary week. */
+    private fun summary(days: List<WeekDay>): String? {
+        val away = days.filter { it.place != null }.groupBy { it.place!! }
+            .map { (place, list) -> "$place: " + list.joinToString(", ") { it.date.shortWeekday().lowercase() } }
+        val moved = days.filter { it.moved }.takeIf { it.isNotEmpty() }
+            ?.let { list -> "перенос: " + list.joinToString(", ") { it.date.shortWeekday().lowercase() } }
+        return (away + listOfNotNull(moved)).joinToString(" · ").ifEmpty { null }
+    }
+}
+
+class WeekWidgetReceiver : GlanceAppWidgetReceiver() {
+    override val glanceAppWidget: GlanceAppWidget = WeekWidget()
+}

android/app/src/main/kotlin/org/xtimms/psu/schedule/work/SyncWorker.kt

@@ -17,6 +17,7 @@ import org.xtimms.psu.schedule.notify.DayAlerts
 import org.xtimms.psu.schedule.notify.LiveLesson
 import org.xtimms.psu.schedule.notify.Reminders
 import org.xtimms.psu.schedule.widget.TodayWidget
+import org.xtimms.psu.schedule.widget.WeekWidget
 import java.util.concurrent.TimeUnit
 
 /**
@@ -61,6 +62,7 @@ class SyncWorker(context: Context, params: WorkerParameters) : CoroutineWorker(c
             LiveLesson.reschedule(context, t, s, app.repository)
             TodayWidget().updateAll(context)
             NextLessonWidget().updateAll(context)
+            WeekWidget().updateAll(context)
             LessonTileService.refresh(context)
         }
     }
@@ -71,6 +73,7 @@ class WidgetTick(context: Context, params: WorkerParameters) : CoroutineWorker(c
     override suspend fun doWork(): Result {
         TodayWidget().updateAll(applicationContext)
         NextLessonWidget().updateAll(applicationContext)
+        WeekWidget().updateAll(applicationContext)
         LessonTileService.refresh(applicationContext)
         return Result.success()
     }

android/app/src/main/res/animator/splash_calendar.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- The calendar grows into place. -->
+<set xmlns:android="http://schemas.android.com/apk/res/android">
+    <objectAnimator
+        android:duration="450"
+        android:interpolator="@interpolator/emphasized_decelerate"
+        android:propertyName="scaleX"
+        android:valueFrom="0.7"
+        android:valueTo="1" />
+    <objectAnimator
+        android:duration="450"
+        android:interpolator="@interpolator/emphasized_decelerate"
+        android:propertyName="scaleY"
+        android:valueFrom="0.7"
+        android:valueTo="1" />
+</set>

android/app/src/main/res/animator/splash_check.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Last, the green check is drawn: the day is sorted. -->
+<objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="350"
+    android:startOffset="400"
+    android:interpolator="@interpolator/emphasized_decelerate"
+    android:propertyName="trimPathEnd"
+    android:valueFrom="0"
+    android:valueTo="1" />

android/app/src/main/res/animator/splash_fade.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- A line of the calendar appears. -->
+<objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="250"
+    android:interpolator="@android:interpolator/linear"
+    android:propertyName="strokeAlpha"
+    android:valueFrom="0"
+    android:valueTo="1" />

android/app/src/main/res/animator/splash_rings.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- The rings fade in as they drop. -->
+<objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="250"
+    android:startOffset="150"
+    android:interpolator="@android:interpolator/linear"
+    android:propertyName="strokeAlpha"
+    android:valueFrom="0"
+    android:valueTo="1" />

android/app/src/main/res/animator/splash_tabs.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- The binder rings drop onto the calendar. -->
+<objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="350"
+    android:startOffset="150"
+    android:interpolator="@interpolator/emphasized_decelerate"
+    android:propertyName="translateY"
+    android:valueFrom="-4"
+    android:valueTo="0" />

android/app/src/main/res/drawable-v31/splash_icon.xml

@@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- The first frame of the launch animation (drawable/splash_icon_animated.xml).
+     The app icon for the launch screen: a blue disc, the calendar, the green check (ios/Config/AppIcon.svg). -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path android:pathData="M54,18a36,36 0,1 1,0 72a36,36 0,1 1,0 -72z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:type="linear"
+                android:startX="54"
+                android:startY="18"
+                android:endX="54"
+                android:endY="90">
+                <item android:offset="0" android:color="#FF1A7FD1" />
+                <item android:offset="1" android:color="#FF004F87" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <group
+        android:name="calendar"
+        android:pivotX="54"
+        android:pivotY="54"
+        android:scaleX="0.7"
+        android:scaleY="0.7">
+        <path
+            android:name="frame"
+            android:pathData="M35.76,40.08H72.24V72.08H35.76Z"
+            android:strokeColor="#FFFFFFFF"
+            android:strokeWidth="3.84"
+            android:strokeLineJoin="round"
+            android:strokeAlpha="0" />
+        <path
+            android:name="header"
+            android:pathData="M35.76,48.72H72.24"
+            android:strokeColor="#FFFFFFFF"
+            android:strokeWidth="3.84"
+            android:strokeLineCap="round"
+            android:strokeAlpha="0" />
+        <group
+            android:name="tabs"
+            android:translateY="-4">
+            <path
+                android:name="rings"
+                android:pathData="M45.68,35.92V43.6M62.32,35.92V43.6"
+                android:strokeColor="#FFFFFFFF"
+                android:strokeWidth="3.84"
+                android:strokeLineCap="round"
+                android:strokeAlpha="0" />
+        </group>
+        <path
+            android:name="check"
+            android:pathData="M45.84,59.92L51.44,65.52L62.48,54.16"
+            android:strokeColor="#FFC8EFB8"
+            android:strokeWidth="4"
+            android:strokeLineCap="round"
+            android:strokeLineJoin="round"
+            android:trimPathEnd="0" />
+    </group>
+</vector>

android/app/src/main/res/drawable/ic_widget_city.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Week widget: a day in another town; tinted by the widget. -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FFFFFFFF"
+        android:pathData="M15,11V5l-3,-3 -3,3v2H3v14h18V11h-6zM7,19H5v-2h2v2zM7,15H5v-2h2v2zM7,11H5V9h2v2zM13,19h-2v-2h2v2zM13,15h-2v-2h2v2zM13,11h-2V9h2v2zM13,7h-2V5h2v2zM19,19h-2v-2h2v2zM19,15h-2v-2h2v2z" />
+</vector>

android/app/src/main/res/drawable/ic_widget_move.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Week widget: a room move; tinted by the widget. -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FFFFFFFF"
+        android:pathData="M6.99,11L3,15l3.99,4v-3H14v-2H6.99v-3zM21,9l-3.99,-4v3H10v2h7.01v3L21,9z" />
+</vector>

android/app/src/main/res/drawable/splash_icon.xml

@@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Before Android 12 the launch icon does not move: its last frame. The animation starts from drawable-v31.
+     The app icon for the launch screen: a blue disc, the calendar, the green check (ios/Config/AppIcon.svg). -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path android:pathData="M54,18a36,36 0,1 1,0 72a36,36 0,1 1,0 -72z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:type="linear"
+                android:startX="54"
+                android:startY="18"
+                android:endX="54"
+                android:endY="90">
+                <item android:offset="0" android:color="#FF1A7FD1" />
+                <item android:offset="1" android:color="#FF004F87" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <group
+        android:name="calendar"
+        android:pivotX="54"
+        android:pivotY="54"
+        android:scaleX="1"
+        android:scaleY="1">
+        <path
+            android:name="frame"
+            android:pathData="M35.76,40.08H72.24V72.08H35.76Z"
+            android:strokeColor="#FFFFFFFF"
+            android:strokeWidth="3.84"
+            android:strokeLineJoin="round"
+            android:strokeAlpha="1" />
+        <path
+            android:name="header"
+            android:pathData="M35.76,48.72H72.24"
+            android:strokeColor="#FFFFFFFF"
+            android:strokeWidth="3.84"
+            android:strokeLineCap="round"
+            android:strokeAlpha="1" />
+        <group
+            android:name="tabs"
+            android:translateY="0">
+            <path
+                android:name="rings"
+                android:pathData="M45.68,35.92V43.6M62.32,35.92V43.6"
+                android:strokeColor="#FFFFFFFF"
+                android:strokeWidth="3.84"
+                android:strokeLineCap="round"
+                android:strokeAlpha="1" />
+        </group>
+        <path
+            android:name="check"
+            android:pathData="M45.84,59.92L51.44,65.52L62.48,54.16"
+            android:strokeColor="#FFC8EFB8"
+            android:strokeWidth="4"
+            android:strokeLineCap="round"
+            android:strokeLineJoin="round"
+            android:trimPathEnd="1" />
+    </group>
+</vector>

android/app/src/main/res/drawable/splash_icon_animated.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- The launch screen's icon, about 750 ms: the calendar grows, its rings drop, the check is drawn. -->
+<animated-vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:drawable="@drawable/splash_icon">
+    <target android:name="calendar" android:animation="@animator/splash_calendar" />
+    <target android:name="frame" android:animation="@animator/splash_fade" />
+    <target android:name="header" android:animation="@animator/splash_fade" />
+    <target android:name="tabs" android:animation="@animator/splash_tabs" />
+    <target android:name="rings" android:animation="@animator/splash_rings" />
+    <target android:name="check" android:animation="@animator/splash_check" />
+</animated-vector>

android/app/src/main/res/interpolator/emphasized_decelerate.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- M3 emphasized decelerate: things entering the screen. -->
+<pathInterpolator xmlns:android="http://schemas.android.com/apk/res/android"
+    android:controlX1="0.05"
+    android:controlY1="0.7"
+    android:controlX2="0.1"
+    android:controlY2="1" />

android/app/src/main/res/values-night/themes.xml

@@ -5,4 +5,12 @@
         <item name="android:statusBarColor">@android:color/transparent</item>
         <item name="android:navigationBarColor">@android:color/transparent</item>
     </style>
+
+    <!-- The launch screen (core-splashscreen): the app surface and the animated icon, then the app. -->
+    <style name="Theme.PsuSchedule.Starting" parent="Theme.SplashScreen">
+        <item name="windowSplashScreenBackground">@color/surface</item>
+        <item name="windowSplashScreenAnimatedIcon">@drawable/splash_icon_animated</item>
+        <item name="windowSplashScreenAnimationDuration">750</item>
+        <item name="postSplashScreenTheme">@style/Theme.PsuSchedule</item>
+    </style>
 </resources>

android/app/src/main/res/values/strings.xml

@@ -17,5 +17,7 @@
     <string name="shortcut_task_long">Новое задание</string>
     <string name="next_widget_name">Следующая пара</string>
     <string name="next_widget_description">Когда следующая пара, что это и в какой аудитории</string>
+    <string name="week_widget_name">Неделя</string>
+    <string name="week_widget_description">Пары каждого дня недели, дни в другом городе и переносы аудиторий</string>
     <string name="tile_name">Пара</string>
 </resources>

android/app/src/main/res/values/themes.xml

@@ -6,4 +6,12 @@
         <item name="android:statusBarColor">@android:color/transparent</item>
         <item name="android:navigationBarColor">@android:color/transparent</item>
     </style>
+
+    <!-- The launch screen (core-splashscreen): the app surface and the animated icon, then the app. -->
+    <style name="Theme.PsuSchedule.Starting" parent="Theme.SplashScreen">
+        <item name="windowSplashScreenBackground">@color/surface</item>
+        <item name="windowSplashScreenAnimatedIcon">@drawable/splash_icon_animated</item>
+        <item name="windowSplashScreenAnimationDuration">750</item>
+        <item name="postSplashScreenTheme">@style/Theme.PsuSchedule</item>
+    </style>
 </resources>

android/app/src/main/res/xml/photo_paths.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Where the camera app may write a photo for a task: the cache, copied and shrunk afterwards. -->
+<paths>
+    <cache-path name="camera" path="camera/" />
+</paths>

android/app/src/main/res/xml/week_widget_info.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
+    android:description="@string/week_widget_description"
+    android:initialLayout="@layout/glance_default_loading_layout"
+    android:minWidth="250dp"
+    android:minHeight="110dp"
+    android:targetCellWidth="4"
+    android:targetCellHeight="2"
+    android:resizeMode="horizontal|vertical"
+    android:updatePeriodMillis="1800000"
+    android:widgetCategory="home_screen" />

android/gradle/libs.versions.toml

@@ -5,6 +5,7 @@ composeBom = "2026.09.01"
 activity = "1.13.0"
 lifecycle = "2.11.0"
 coreKtx = "1.19.1"
+splashscreen = "1.2.0"
 coroutines = "1.11.0"
 serialization = "1.11.0"
 okhttp = "4.12.0"
@@ -27,6 +28,8 @@ activity-compose = { module = "androidx.activity:activity-compose", version.ref
 lifecycle-viewmodel-compose = { module = "androidx.lifecycle:lifecycle-viewmodel-compose", version.ref = "lifecycle" }
 lifecycle-runtime-compose = { module = "androidx.lifecycle:lifecycle-runtime-compose", version.ref = "lifecycle" }
 core-ktx = { module = "androidx.core:core-ktx", version.ref = "coreKtx" }
+# The launch screen with the animated icon on every Android version (Android 12+ draws its own).
+splashscreen = { module = "androidx.core:core-splashscreen", version.ref = "splashscreen" }
 coroutines-android = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-android", version.ref = "coroutines" }
 serialization-json = { module = "org.jetbrains.kotlinx:kotlinx-serialization-json", version.ref = "serialization" }
 okhttp = { module = "com.squareup.okhttp3:okhttp", version.ref = "okhttp" }

scripts/snapshot-lines.js

@@ -15,7 +15,11 @@ export const lessonLine = (l) =>
     // The town only when the cell names one or the day's note puts the lesson there.
     [l.room, l.place].filter(Boolean).join(", "),
     l.teacher,
-    [...l.groups, ...l.subgroups.map((s) => `${s.group}/${s.label.replace("Подгруппа ", "п")}`)].join(","),
+    [...l.groups, ...l.subgroups.map((s) => `${s.group}/${s.label.replace("Подгруппа ", "п")}`)].join(",") +
+      // "Немецкий язык" or "Французский язык": a part of the group takes one of them.
+      (l.option ? " · на выбор" : "") +
+      // Russian for foreign students while the others have physical education.
+      (l.audience === "foreign" ? " · иностранцам" : l.audience === "local" ? " · кроме иностранцев" : ""),
   ]
     .map((part) => String(part ?? "").replace(/\s+/g, " ").trim())
     .join(" | ");

server/index.js

@@ -80,7 +80,9 @@ app.use("/api", (_req, res, next) => {
 // 12 — a JSON log line per request;
 // 13 — the dashboard at /status (password), /api/health only says alive, ready and versions;
 // 14 — a lesson's `place` and a day's `places` ("Занятия в Полоцке") in /api/timetable.
-const API_VERSION = 14;
+// 15 — a lesson's `option` and the group's `choices` (German or French for parts of a group),
+//      a lesson's `audience` (foreign students or the others) and the group's `audience` flag.
+const API_VERSION = 15;
 
 /**
  * What the server still waits for before it answers from memory: the catalog, the week table

server/parser.js

@@ -10,7 +10,7 @@ import { parseWeekRanges, parseTextDates, DATE_LIST, weekday } from "../shared/w
 import { roomMoves, onlyPlace, weekPlan, partsByWeek } from "./rooms.js";
 import { placeNote, lessonPlace, placeOf } from "./places.js";
 const run = promisify(execFile);
-export const PARSER_VERSION = 15;
+export const PARSER_VERSION = 17;
 const days = [
   "понедельник",
   "вторник",
@@ -206,17 +206,89 @@ function byKind(text) {
   return [`${weeks(m[1])} ${at(m[2])}`, `${weeks(m[3])} ${at(m[4])}`];
 }
 
+// Who a lesson is for: "(для иностранных студентов)", "Русский язык как иностранный" are for
+// foreign students only, "(кроме иностр.студ.)" for the others.
+const FOR_FOREIGN = /\(\s*для\s+иностр[^)]*\)/iu;
+const NOT_FOREIGN = /\(\s*кроме\s+иностр[^)]*\)/iu;
+const FOREIGN_SUBJECT = /как\s+иностранн/iu;
+export function audienceOf(text) {
+  if (NOT_FOREIGN.test(text)) return "local";
+  if (FOR_FOREIGN.test(text) || FOREIGN_SUBJECT.test(text)) return "foreign";
+  return null;
+}
+/**
+ * One cell, two lessons at once: Russian for foreign students while the others have another
+ * lesson. "Ф и з и ч е с к а я к у л ь т у р а\nРусский язык как иностранный (для иностранных
+ * студентов) Семченко Е.Д. ауд.313н" or "Русский язык как иностранный (п.з.) Немирская В.А. 331Е
+ * ФИЗИЧЕСКАЯ КУЛЬТУРА". A line with only the teacher below the lesson ("Хаткевич Т.В. ауд. 323н")
+ * is no lesson of its own.
+ */
+// "Новополоцк" or "17.00" before a lesson is its town or time, not another lesson.
+const aLesson = (text) =>
+  /(?:[А-ЯЁа-яё]\s?){3}/u.test(lessonPlace(text).rest.replace(/\d{1,2}[.:]\d{2}|(?:г\.\s*)?(?:ново)?полоцк[а-яё]*/giu, ""));
+export function byAudience(text) {
+  const lines = text.split("\n");
+  const at = lines.findIndex(
+    (line, i) => i > 0 && audienceOf(line) === "foreign" && !/^\s*[А-ЯЁ][а-яё-]+\s+[А-ЯЁ]\.\s*[А-ЯЁ]\./u.test(line),
+  );
+  const head = lines.slice(0, at).join("\n");
+  if (at > 0 && audienceOf(head) !== "foreign" && aLesson(head))
+    return [
+      { text: lines.slice(0, at).join("\n").trim(), audience: "local" },
+      { text: lines.slice(at).join("\n").trim(), audience: "foreign" },
+    ];
+  // "… Немирская В.А. 331Е со 2 нед. ФИЗИЧЕСКАЯ КУЛЬТУРА": the others' lesson in capitals after it.
+  const tail = text.match(
+    /^([\s\S]*?(?:\d{2,3}\s*[А-ЯЁа-яё]?|[А-ЯЁ]\.))\s+((?:(?:с|со)\s*)?(?:\d{1,2}(?:\s*[-–,]\s*\d{1,2})*\s*н(?:ед)?\.?\s+)?[А-ЯЁ]{3,}(?:\s+[А-ЯЁ]{3,})+)\s*$/u,
+  );
+  if (tail && audienceOf(tail[1]) === "foreign" && !audienceOf(tail[2]))
+    return [
+      { text: tail[1].trim(), audience: "foreign" },
+      { text: tail[2].trim(), audience: "local" },
+    ];
+  // "Ф и з и ч е с к а я к у л ь т у р а 24-КФ: Русский язык как иностранный …" on one line.
+  const inline = text.match(/^((?:[А-ЯЁа-яё]\s?){3}[^\n]*?)\s+((?:\d{2}-[^\s:]+:\s*)?Русский\s+язык\s+как\s+иностранн[\s\S]*)$/u);
+  if (inline && !audienceOf(inline[1]) && aLesson(inline[1]))
+    return [
+      { text: inline[1].trim(), audience: "local" },
+      { text: inline[2].trim(), audience: "foreign" },
+    ];
+  return null;
+}
+
+// "25-ДОи", "24-ТНГи-2": a group of foreign students.
+const FOREIGN_GROUP = /[А-ЯЁа-яё]и(?:-\d+)?$/u;
+// A line that is a whole lesson: a subject, its kind in brackets and a teacher.
+const WHOLE_LESSON = /^\s*[А-ЯЁ][^\n]*?\((?:л|п\.?\s*з|л\.?\s*з|лаб|пр|сем)\.?\)[^\n]*?[А-ЯЁ][а-яё-]+\s+[А-ЯЁ]\.\s*[А-ЯЁ]\./u;
+/**
+ * "Немецкий язык (п.з) – Найверт Ю.О. 208А,\nФранцузский язык (п.з.) – Глобенко М.В. 336Е":
+ * one cell over the whole group, two lessons at once for the parts of the group that study one
+ * or the other. A line without a subject of its own ("321Д") stays with the lesson above.
+ */
+export function parallel(text) {
+  const parts = [];
+  for (const line of text.split("\n")) {
+    if (!parts.length || WHOLE_LESSON.test(line)) parts.push(line);
+    else parts[parts.length - 1] += "\n" + line;
+  }
+  if (parts.length < 2 || !parts.every((p) => WHOLE_LESSON.test(p))) return [text];
+  return parts.map((p) => p.trim().replace(/[,;]+$/, ""));
+}
+
 /**
  * A cell's entries, each `{text, main, plan}`: the whole text, its first line (subject, kind,
  * teacher and room are read from it) and the plan. A line that names only rooms or teachers by week
  * ("1-9н. 502н", "с 10н. – 359", "2-9н.-Клос О.Ю., 10-14н.-Конторов В.Э.") belongs to the lesson
  * above: its plan of rooms and teachers by week. A line with weeks and a kind but no subject
  * ("7,9,11н. – (п.з.) Савицкая К.Д. ауд. А1-06 8,12,14н. – (п.з.) …") is the subject above in
- * other weeks. A stray "." is no lesson.
+ * other weeks. A stray "." is no lesson. Lessons side by side for parts of the group ([parallel])
+ * also carry `choice`: the subjects to choose from.
  */
 export function entries(raw) {
   const out = [];
-  for (const alternative of alternatives(raw).flatMap(byKind)) {
+  for (const part of alternatives(raw).flatMap(byKind)) {
+    // "…Третьяк З.И. 331Е,\n2-13н. …": the comma before the next lesson is not part of the room.
+    const alternative = part.replace(/[,;]\s*$/, "");
     if (!/[\p{L}\d]/u.test(alternative)) continue;
     const prev = out.at(-1);
     if (prev && onlyPlace(alternative)) {
@@ -238,6 +310,24 @@ export function entries(raw) {
       }
       continue;
     }
+    const options = parallel(alternative);
+    // "Теория языка (кроме иностр.студ.) … / История языка (для иностр.студ.) …": not a choice,
+    // each lesson is for its own students.
+    const marks = options.map(audienceOf);
+    if (options.length > 1 && marks.every(Boolean)) {
+      options.forEach((o, i) => out.push({ text: o, main: o, plan: [], audience: marks[i] }));
+      continue;
+    }
+    const split = byAudience(alternative);
+    if (split) {
+      for (const p of split) out.push({ text: p.text, main: p.text, plan: weekPlan(p.text).filter((w) => w.color), audience: p.audience });
+      continue;
+    }
+    if (options.length > 1) {
+      const choice = options.map((o) => details(o).subject);
+      for (const o of options) out.push({ text: o, main: o, plan: [], choice });
+      continue;
+    }
     // "бел.н.504н/зел.н.524н": a room for white weeks and one for green ones.
     out.push({ text: alternative, main: alternative, plan: weekPlan(alternative).filter((p) => p.color) });
   }
@@ -400,6 +490,8 @@ export function parseDocx(buffer, source = {}) {
   const lessons = [],
     // "Занятия в Полоцке": the days a group, or one of its subgroups, spends in another town.
     places = [],
+    // Subjects that parts of a group choose between: the second foreign language, an elective.
+    choices = [],
     groups = new Set(),
     warnings = new Set();
   // The catalog folder ("2026–2027") wins: some files keep last year's header text.
@@ -576,11 +668,23 @@ export function parseDocx(buffer, source = {}) {
           raw = note.rest;
           if (!raw.trim()) return;
         }
-        for (const { text: whole, main: alternative, plan } of entries(raw)) {
+        for (const { text: whole, main, plan, choice, audience } of entries(raw)) {
+          if (choice) choices.push({ groups: targetGroups, options: choice });
+          // "24-КФ: Русский язык как иностранный": one of the cell's groups.
+          let alternative = main;
+          let lessonGroups = targetGroups;
+          const named = main.match(/^\s*([^:\n]{4,24}):\s+(?=\S)/u);
+          const only = named ? groupsIn(named[1]) : [];
+          if (only.length && only.every((g) => targetGroups.includes(g))) {
+            lessonGroups = only;
+            alternative = main.slice(named[0].length);
+          }
           // "Единый день информирования 10.09;15.10;19.11;17.12": the dates are not part of the
           // subject, nor is a move to another room on a date ("412н 26.10.2026-333").
           const read = (text) => {
-            const data = details(roomMoves(text).rest.replace(DATE_LIST, "").replace(/[ \t]{2,}/g, " ").trim());
+            // "(для иностранных студентов)" is who the lesson is for, no part of its name or room.
+            const plain = text.replace(FOR_FOREIGN, " ").replace(NOT_FOREIGN, " ");
+            const data = details(roomMoves(plain).rest.replace(DATE_LIST, "").replace(/[ \t]{2,}/g, " ").trim());
             if (credits && data.type === "Занятие") data.type = "Зачёт";
             return data;
           };
@@ -618,7 +722,7 @@ export function parseDocx(buffer, source = {}) {
             ...(start && { start, end: lead.end }),
             ...data,
             ...overrides,
-            groups: targetGroups,
+            groups: lessonGroups,
             subgroups,
             variant: spansBoth ? "all" : variant,
             weekRanges:
@@ -633,6 +737,10 @@ export function parseDocx(buffer, source = {}) {
                 ? cell.color
                 : null,
             raw: whole,
+            ...(choice && { option: data.subject }),
+            // Groups of foreign students alone ("25-ДОи") have Russian as everyone's lesson.
+            ...((audience || audienceOf(whole)) &&
+              !lessonGroups.every(FOREIGN_GROUP.test.bind(FOREIGN_GROUP)) && { audience: audience || audienceOf(whole) }),
             // Rooms and teachers by week, or by the week's colour.
             ...(plan.length && { plan }),
           });
@@ -696,6 +804,19 @@ export function parseDocx(buffer, source = {}) {
   const labels = new Map();
   for (const l of lessons)
     for (const s of l.subgroups) labels.set(s.group, new Set([...(labels.get(s.group) || []), s.label]));
+  // The chosen subject on its own in a cell ("Немецкий язык" on Thursday) is the same choice:
+  // only that part of the group has it.
+  const norm = (s) => s.toLowerCase().replace(/\s+/g, " ").trim();
+  const sets = [];
+  for (const c of choices) {
+    const key = c.groups.join("|") + "#" + c.options.map(norm).sort().join("|");
+    if (!sets.some((s) => s.key === key)) sets.push({ key, groups: c.groups, options: c.options });
+  }
+  for (const lesson of lessons) {
+    if (lesson.option || lesson.subgroups.length) continue;
+    const set = sets.find((s) => s.groups.some((g) => lesson.groups.includes(g)) && s.options.some((o) => norm(o) === norm(lesson.subject)));
+    if (set) lesson.option = set.options.find((o) => norm(o) === norm(lesson.subject));
+  }
   for (const lesson of lessons) {
     if (lesson.place || !places.length) continue;
     const place = placeOf(lesson, places, (group) => [...(labels.get(group) || [])]);
@@ -708,6 +829,7 @@ export function parseDocx(buffer, source = {}) {
       (a, b) => a.day - b.day || a.start.localeCompare(b.start),
     ),
     ...(places.length && { places }),
+    ...(sets.length && { choices: sets.map(({ groups, options }) => ({ groups, options })) }),
     notes: document.notes,
     warnings: [...warnings],
     source: {

server/timetable.js

@@ -31,6 +31,10 @@ function lessonOut(lesson, group, people, date, status, calendar, week = null) {
     condition: lesson.condition,
     variant: lesson.variant,
     subgroup: lesson.subgroups.find((s) => s.group === group)?.label || null,
+    // "Немецкий язык" when part of the group studies German and part French (see `choices`).
+    option: lesson.option || null,
+    // "foreign": for foreign students only (Russian as a foreign language); "local": for the others.
+    audience: lesson.audience || null,
     groups: lesson.groups,
     uncertain: status === "maybe",
     raw: lesson.raw,
@@ -159,6 +163,10 @@ export function timetable({ file, schedule, calendar, group, from, days, range,
         ...extra.map((e) => e.lesson.subgroups?.find((s) => s.group === group)?.label).filter(Boolean),
       ]),
     ].sort((a, b) => a.localeCompare(b, "ru", { numeric: true })),
+    // What parts of the group choose between: [["Немецкий язык", "Французский язык"]].
+    choices: (schedule.choices || []).filter((c) => c.groups.includes(group)).map((c) => c.options),
+    // Some lessons are for foreign students only, or for the others: worth asking which one you are.
+    audience: lessons.some((l) => l.audience),
     bells: calendar?.bells || [],
     from,
     days: out,

test/formats.test.js

@@ -1,6 +1,6 @@
 import { test } from "node:test";
 import assert from "node:assert/strict";
-import { groupsIn, alternatives, entries, details, leadingTime } from "../server/parser.js";
+import { groupsIn, alternatives, entries, details, leadingTime, parallel, audienceOf } from "../server/parser.js";
 import { roomMoves, weekPlan, onlyPlace } from "../server/rooms.js";
 import { peopleAndRooms, roomsOn, teachersOn, movedOn } from "../server/directory.js";
 
@@ -118,6 +118,40 @@ test("Подгруппа в тексте ячейки, точка вместо
   assert.equal(details("Интеллектуальная собственность - драйвер инновационного развития\nна пространстве Евразии").subject.includes("Евразии"), true);
 });
 
+test("Немецкий или французский: два занятия в одной ячейке на всю группу", () => {
+  const cell = "Немецкий язык (п.з) – Найверт Ю.О. 208А,\nФранцузский язык (п.з.) – Глобенко М.В. 336Е";
+  const list = entries(cell);
+  assert.deepEqual(list.map((e) => details(e.main).room), ["208А", "336Е"]);
+  assert.deepEqual(list.map((e) => details(e.main).teacher), ["Найверт Ю.О.", "Глобенко М.В."]);
+  assert.deepEqual(list[0].choice, ["Немецкий язык", "Французский язык"]);
+  // A room on its own line stays with its lesson.
+  assert.deepEqual(
+    parallel("Теория языка (англ.) (л.) (кроме иностр.студ.)-Чеботарева Е.М.305Г\nИстория языка (англ.) (л) (для иностр.студ.) Третьяк З.И.\n321Д").at(-1),
+    "История языка (англ.) (л) (для иностр.студ.) Третьяк З.И.\n321Д",
+  );
+  // A lesson with its teacher on the next line is one lesson.
+  assert.equal(entries("Русский язык как иностранный (п.з.)\nНемирская В.А. 305Г").length, 1);
+  // The comma before the next week's lesson is no part of the room.
+  assert.equal(details(entries("2-13н. Белорусский язык (п.з.) - Третьяк З.И. 331Е,\n2-13н. Стилистика (п.з.) – Коротких А.В. 301Г")[0].main).room, "331Е");
+});
+
+test("Пары для иностранных студентов и для остальных", () => {
+  assert.equal(audienceOf("История языка (п.з.) (кроме иностр.студ.) Ковшик О.С. 305Г"), "local");
+  assert.equal(audienceOf("Русский язык как иностранный (п.з.) Немирская В.А. 305Г"), "foreign");
+  assert.equal(audienceOf("Современный разговорный иностранный язык (на базе второго иностранного языка)"), null);
+  // Russian for foreign students while the others have physical education, in every spelling.
+  const pe = (text) => entries(text).map((e) => [details(e.main).subject, e.audience]);
+  assert.deepEqual(pe("Ф и з и ч е с к а я к у л ь т у р а\nРусский язык как иностранный (для иностранных студентов) Семченко Е.Д. ауд.313н"), [
+    ["Ф и з и ч е с к а я к у л ь т у р а", "local"],
+    ["Русский язык как иностранный (для иностранных студентов)", "foreign"],
+  ]);
+  assert.deepEqual(pe("со 2 нед. Русский язык как иностранный (п.з.) Немирская В.А. 331Е со 2 нед. ФИЗИЧЕСКАЯ КУЛЬТУРА").map((p) => p[1]), ["foreign", "local"]);
+  assert.equal(details(entries("Русский язык как иностранный (п.з.) Немирская В.А. 331Е ФИЗИЧЕСКАЯ КУЛЬТУРА")[0].main).room, "331Е");
+  // The town or the teacher on a line of its own is no lesson for the others.
+  assert.equal(entries("17.00 Новополоцк\nРусский язык как иностранный (п.з.)\nКириллова В.С. ауд. 537н").length, 1);
+  assert.equal(entries("Русский язык как иностранный (для иностранных студентов)\nХаткевич Т.В. ауд. 323н").length, 1);
+});
+
 test("Старое имя разделённой группы: понятная ошибка, другое написание — та же группа", async () => {
   const { timetable } = await import("../server/timetable.js");
   const schedule = { groups: ["24-ИЯ (РА)и-1", "24-ИЯ (РА)и-2"], lessons: [], notes: [], period: "Осенний семестр", source: {} };

test/snapshots/fkne-daily.txt

@@ -17,7 +17,7 @@
 вт 15:20–16:45 | каждую неделю, нижняя строка | Физический практикум: физика атома | Занятие | 210н | Окунев Д.О. | 24-КФ,24-КФ/п2
 вт 15:20–16:45 | нед. 2-14, верхняя строка | Криптографические методы защиты информации | Лабораторная | 421н | Кухта С.В. | 24-КБ,24-КБ/п2
 вт 17:00–18:25 | нед. 1-13, верхняя строка | Криптографические методы защиты информации | Лабораторная | 421н | Кухта С.В. | 24-КБ,24-КБ/п1
-пн 08:30–09:55 | каждую неделю | Русский язык как иностранный (для иностранных студентов) | Занятие | 412н | Козыренко А.Н. | 24-КБ
+пн 08:30–09:55 | каждую неделю | Русский язык как иностранный | Занятие | 412н | Козыренко А.Н. | 24-КБ · иностранцам
 пн 10:05–11:30 | каждую неделю | Уравнения математической физики | Лекция | 336н | Козлов А.А. | 24-КБ
 пн 11:45–13:10 | каждую неделю | Операционные системы | Лекция | 343 | Бураченок А.Л. | 24-КБ
 пн 11:45–13:10 | каждую неделю | Электродинамика | Лекция | 402н | Вабищевич С.А. | 24-КФ
@@ -60,7 +60,8 @@
 сб 11:45–13:10 | каждую неделю, верхняя строка | Компьютерные сети | Лабораторная | 215н | Филиппов Ю.И. | 24-КБ,24-КБ/п1
 сб 11:45–13:10 | каждую неделю, нижняя строка | Компьютерные сети | Лабораторная | 215н | Филиппов Ю.И. | 24-КБ,24-КБ/п2
 ср 10:05–11:30 | нед. 2-14 | Модуль «Майнор» | Занятие |  |  | 24-КБ,24-КФ
-чт 08:30–09:55 | каждую неделю | Ф и з и ч е с к а я к у л ь т у р а 24-КФ: Русский язык как иностранный (для иностранных студентов) | Занятие | 537н | Кириллова В.С. | 24-КБ,24-КФ
+чт 08:30–09:55 | каждую неделю | Русский язык как иностранный | Занятие | 537н | Кириллова В.С. | 24-КФ · иностранцам
+чт 08:30–09:55 | каждую неделю | Ф и з и ч е с к а я к у л ь т у р а | Занятие |  |  | 24-КБ,24-КФ · кроме иностранцев
 чт 10:05–11:30 | каждую неделю, верхняя строка | Криптографические методы защиты информации | Лекция | 329н | Кухта С.В. | 24-КБ
 чт 10:05–11:30 | каждую неделю, верхняя строка | Основы математического моделирования | Лабораторная | 215н | Сковородко М.А. | 24-КФ,24-КФ/п1
 чт 10:05–11:30 | каждую неделю, верхняя строка | Основы радиоэлектроники | Лабораторная | 406н | Грозберг Ю.Г. | 24-КФ,24-КФ/п2

test/snapshots/gf-daily.txt

@@ -1,5 +1,6 @@
 # Осенний семестр · 25-РГФ-1, 25-РГФ-2
-вт 08:30–09:55 | каждую неделю | Немецкий язык | Практика | 336Е | Найверт Ю.О. | 25-РГФ-1
+вт 08:30–09:55 | каждую неделю | Немецкий язык | Практика | 319Д | Найверт Ю.О. | 25-РГФ-1 · на выбор
+вт 08:30–09:55 | каждую неделю | Французский язык | Практика | 336Е | Глобенко М.В. | 25-РГФ-1 · на выбор
 вт 10:05–11:30 | нед. 2-14 | Философия | Практика | 206Г | Андрейчик Е.В. | 25-РГФ-1,25-РГФ-2
 вт 11:45–13:10 | каждую неделю | Английский язык | Практика | 133Е | Лагун А.М. | 25-РГФ-2
 вт 11:45–13:10 | нед. 1-13 | История литературы страны изучаемого языка XVII века | Лекция | 305Г | Смулькевич А.А. | 25-РГФ-1
@@ -10,18 +11,20 @@
 вт 15:20–16:45 | каждую неделю, нижняя строка | Современный разговорный иностранный язык (англ.) | Практика | 203Г | Ковшик О.С. | 25-РГФ-1,25-РГФ-1/п1
 вт 15:20–16:45 | каждую неделю, нижняя строка | Современный разговорный иностранный язык (англ.) | Практика | 304Г | Федорович Н.Я. | 25-РГФ-1,25-РГФ-1/п2
 вт 15:20–16:45 | нед. с 3, верхняя строка | Политология | Практика | 206Г | Радюк А.Л. | 25-РГФ-1,25-РГФ-2
-пн 08:30–09:55 | каждую неделю | Русский язык как иностранный | Практика | 305Г | Немирская В.А. | 25-РГФ-1,25-РГФ-1/п1
+пн 08:30–09:55 | каждую неделю | Русский язык как иностранный | Практика | 305Г | Немирская В.А. | 25-РГФ-1,25-РГФ-1/п1 · иностранцам
-пн 10:05–11:30 | каждую неделю | Немецкий язык | Практика | 336Е | Найверт Ю.О. | 25-РГФ-1
+пн 10:05–11:30 | каждую неделю | Немецкий язык | Практика | 208А | Найверт Ю.О. | 25-РГФ-1 · на выбор
 пн 10:05–11:30 | каждую неделю | Основы перевода | Практика | 331Е | Семченок Л.И. | 25-РГФ-2
+пн 10:05–11:30 | каждую неделю | Французский язык | Практика | 336Е | Глобенко М.В. | 25-РГФ-1 · на выбор
 пн 11:45–13:10 | каждую неделю | ФИЗИЧЕСКАЯ КУЛЬТУРА | Занятие |  |  | 25-РГФ-1,25-РГФ-2
 пн 13:40–15:05 | каждую неделю | Практика устной и письменной речи (англ.) | Практика | 331Е | Федорович Н.Я. | 25-РГФ-1,25-РГФ-1/п2
 пн 13:40–15:05 | каждую неделю | Практическая фонетика (англ) | Практика | 319Д | Кунчевская А.В. | 25-РГФ-1,25-РГФ-1/п1
 пн 13:40–15:05 | каждую неделю | Практическая фонетика (нем) | Практика | 330Е | Логвинова И.В. | 25-РГФ-2
 пн 15:20–16:45 | каждую неделю | Английский язык | Практика | 248Ж | Лагун А.М. | 25-РГФ-2
-пн 15:20–16:45 | каждую неделю | Немецкий язык | Практика | 336Е | Найверт Ю.О. | 25-РГФ-1
+пн 15:20–16:45 | каждую неделю | Немецкий язык | Практика | 332Е | Найверт Ю.О. | 25-РГФ-1 · на выбор
+пн 15:20–16:45 | каждую неделю | Французский язык | Практика | 336Е | Глобенко М.В. | 25-РГФ-1 · на выбор
 пт 08:30–09:55 | каждую неделю | Основы перевода | Практика | 208А | Семченок Л.И. | 25-РГФ-2
-пт 08:30–09:55 | каждую неделю, верхняя строка | Русский язык как иностранный | Практика | 307Г | Немирская В.А. | 25-РГФ-1,25-РГФ-1/п1
+пт 08:30–09:55 | каждую неделю, верхняя строка | Русский язык как иностранный | Практика | 307Г | Немирская В.А. | 25-РГФ-1,25-РГФ-1/п1 · иностранцам
-пт 08:30–09:55 | каждую неделю, нижняя строка | Французский язык | Практика | 336Е | Глобенко М.В. | 25-РГФ-1
+пт 08:30–09:55 | каждую неделю, нижняя строка | Французский язык | Практика | 336Е | Глобенко М.В. | 25-РГФ-1 · на выбор
 пт 10:05–11:30 | каждую неделю | История зарубежной литературы Средних веков и Возрождения | Практика | 305Г | Лушневская Е.В. | 25-РГФ-1,25-РГФ-2
 пт 11:45–13:10 | каждую неделю | Основы перевода | Практика | 203Г | Смулькевич А.А. | 25-РГФ-1
 пт 11:45–13:10 | нед. 1-13 | История литературы страны изучаемого языка XVII века | Лекция | 248Ж | Гордеенок Т.М. | 25-РГФ-2
@@ -43,19 +46,20 @@
 ср 10:05–11:30 | каждую неделю, нижняя строка | Коммуникативная грамматика | Практика | 304Г | Ковшик О.С. | 25-РГФ-1,25-РГФ-1/п1
 ср 10:05–11:30 | каждую неделю, нижняя строка | Коммуникативная грамматика | Практика | 308Г | Протас А.А. | 25-РГФ-1,25-РГФ-1/п2
 ср 10:05–11:30 | нед. 2-15 | История языка | Практика | 248Ж | Логвинова И.В. | 25-РГФ-2
-ср 11:45–13:10 | нед. с 2 | Русский язык как иностранный | Практика |  | Немирская В.А. | 25-РГФ-1,25-РГФ-2
+ср 11:45–13:10 | нед. с 2 | Русский язык как иностранный | Практика | 331Е | Немирская В.А. | 25-РГФ-1,25-РГФ-2 · иностранцам
-ср 13:40–15:05 | нед. 2-15 | История языка | Практика | 305Г | Ковшик О.С. | 25-РГФ-1
+ср 11:45–13:10 | нед. с 2 | ФИЗИЧЕСКАЯ КУЛЬТУРА | Занятие |  |  | 25-РГФ-1,25-РГФ-2 · кроме иностранцев
+ср 13:40–15:05 | нед. 2-15 | История языка | Практика | 305Г | Ковшик О.С. | 25-РГФ-1 · кроме иностранцев
 ср 15:20–16:45 | нед. 2-15 | Философия | Лекция | 211А | Борун Е.Н. | 25-РГФ-1,25-РГФ-2
-чт 08:30–09:55 | каждую неделю | Русский язык как иностранный | Практика | 307Г | Немирская В.А. | 25-РГФ-1,25-РГФ-1/п1
+чт 08:30–09:55 | каждую неделю | Русский язык как иностранный | Практика | 307Г | Немирская В.А. | 25-РГФ-1,25-РГФ-1/п1 · иностранцам
 чт 08:30–09:55 | каждую неделю, верхняя строка | Современный разговорный иностранный язык (англ.) | Практика | 304Г | Федорович Н.Я. | 25-РГФ-1,25-РГФ-1/п2
 чт 08:30–09:55 | каждую неделю, нижняя строка | Практика устной и письменной речи (англ.) | Практика | 304Г | Федорович Н.Я. | 25-РГФ-1,25-РГФ-1/п2
 чт 10:05–11:30 | каждую неделю, верхняя строка | История зарубежной литературы Средних веков и Возрождения | Лекция | 305Г | Лушневская Е.В. | 25-РГФ-1,25-РГФ-2
-чт 10:05–11:30 | каждую неделю, нижняя строка | История языка | Лекция | 305Г | Третьяк З.И. | 25-РГФ-1
+чт 10:05–11:30 | каждую неделю, нижняя строка | История языка | Лекция | 305Г | Третьяк З.И. | 25-РГФ-1 · кроме иностранцев
 чт 10:05–11:30 | каждую неделю, нижняя строка | Современный разговорный иностранный язык (нем.) | Практика | 248Ж | Белоусова Э.А. | 25-РГФ-2
 чт 11:45–13:10 | каждую неделю | Английский язык | Практика | 248Ж | Лагун А.М. | 25-РГФ-2
 чт 11:45–13:10 | каждую неделю | Основы перевода | Практика | 120Д | Смулькевич А.А. | 25-РГФ-1
 чт 13:40–15:05 | даты 2026-09-10,2026-10-15,2026-11-19,2026-12-17 | Единый день информирования: 10 сентября, 15 октября, 19 ноября, 17 декабря | Занятие |  |  | 25-РГФ-1,25-РГФ-2
 чт 13:40–15:05 | каждую неделю | Практика устной и письменной речи (нем.) | Практика | 248Ж | Белоусова Э.А. | 25-РГФ-2
 чт 13:40–15:05 | нед. 1-13 | История литературы страны изучаемого языка XVII века | Практика | 319Д | Смулькевич А.А. | 25-РГФ-1
-чт 15:20–16:45 | каждую неделю | Немецкий язык | Практика | 208А | Найверт Ю.О. | 25-РГФ-1
+чт 15:20–16:45 | каждую неделю | Немецкий язык | Практика | 208А | Найверт Ю.О. | 25-РГФ-1 · на выбор
 чт 15:20–16:45 | каждую неделю | Практическая грамматика (нем.) | Практика | 248Ж | Белоусова Э.А. | 25-РГФ-2