Made synchronization server address configurable

app/src/main/AndroidManifest.xml

@@ -95,6 +95,7 @@
 
 				<data android:scheme="kotatsu" />
 				<data android:host="about" />
+				<data android:host="sync-settings" />
 			</intent-filter>
 		</activity>
 		<activity

app/src/main/java/org/koitharu/kotatsu/core/prefs/AppSettings.kt

@@ -388,6 +388,7 @@ class AppSettings @Inject constructor(@ApplicationContext context: Context) {
 		const val KEY_EXIT_CONFIRM = "exit_confirm"
 		const val KEY_INCOGNITO_MODE = "incognito"
 		const val KEY_SYNC = "sync"
+		const val KEY_SYNC_SETTINGS = "sync_settings"
 		const val KEY_READER_BAR = "reader_bar"
 		const val KEY_READER_SLIDER = "reader_slider"
 		const val KEY_SHORTCUTS = "dynamic_shortcuts"

app/src/main/java/org/koitharu/kotatsu/settings/DomainValidator.kt

@@ -1,20 +1,17 @@
 package org.koitharu.kotatsu.settings
 
 import okhttp3.HttpUrl
-import okhttp3.internal.toCanonicalHost
 import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.utils.EditTextValidator
 
 class DomainValidator : EditTextValidator() {
 
-	private val urlBuilder = HttpUrl.Builder()
-
 	override fun validate(text: String): ValidationResult {
 		val trimmed = text.trim()
 		if (trimmed.isEmpty()) {
 			return ValidationResult.Success
 		}
-		return if (!checkCharacters(trimmed) || trimmed.toCanonicalHost() == null) {
+		return if (!checkCharacters(trimmed)) {
 			ValidationResult.Failed(context.getString(R.string.invalid_domain_message))
 		} else {
 			ValidationResult.Success
@@ -22,6 +19,12 @@ class DomainValidator : EditTextValidator() {
 	}
 
 	private fun checkCharacters(value: String): Boolean = runCatching {
-		urlBuilder.host(value)
+		val parts = value.split(':')
+		require(parts.size <= 2)
+		val urlBuilder = HttpUrl.Builder()
+		urlBuilder.host(parts.first())
+		if (parts.size == 2) {
+			urlBuilder.port(parts[1].toInt())
+		}
 	}.isSuccess
 }

app/src/main/java/org/koitharu/kotatsu/settings/ServicesSettingsFragment.kt

@@ -153,6 +153,7 @@ class ServicesSettingsFragment : BasePreferenceFragment(R.string.services) {
 					else -> getString(R.string.disabled)
 				}
 			}
+			findPreference<Preference>(AppSettings.KEY_SYNC_SETTINGS)?.isEnabled = account != null
 		}
 	}
 }

app/src/main/java/org/koitharu/kotatsu/settings/SettingsActivity.kt

@@ -137,6 +137,7 @@ class SettingsActivity :
 			Intent.ACTION_VIEW -> {
 				when (intent.data?.host) {
 					HOST_ABOUT -> AboutSettingsFragment()
+					HOST_SYNC_SETTINGS -> SyncSettingsFragment()
 					else -> SettingsHeadersFragment()
 				}
 			}
@@ -159,6 +160,7 @@ class SettingsActivity :
 		private const val ACTION_MANAGE_SOURCES = "${BuildConfig.APPLICATION_ID}.action.MANAGE_SOURCES_LIST"
 		private const val EXTRA_SOURCE = "source"
 		private const val HOST_ABOUT = "about"
+		private const val HOST_SYNC_SETTINGS = "sync-settings"
 
 		fun newIntent(context: Context) = Intent(context, SettingsActivity::class.java)
 

app/src/main/java/org/koitharu/kotatsu/settings/SyncSettingsFragment.kt

@@ -0,0 +1,49 @@
+package org.koitharu.kotatsu.settings
+
+import android.os.Bundle
+import android.view.View
+import androidx.fragment.app.FragmentResultListener
+import androidx.preference.Preference
+import dagger.hilt.android.AndroidEntryPoint
+import org.koitharu.kotatsu.R
+import org.koitharu.kotatsu.base.ui.BasePreferenceFragment
+import org.koitharu.kotatsu.sync.data.SyncSettings
+import org.koitharu.kotatsu.sync.ui.SyncHostDialogFragment
+import javax.inject.Inject
+
+@AndroidEntryPoint
+class SyncSettingsFragment : BasePreferenceFragment(R.string.sync_settings), FragmentResultListener {
+
+	@Inject
+	lateinit var syncSettings: SyncSettings
+
+	override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
+		addPreferencesFromResource(R.xml.pref_sync)
+		bindHostSummary()
+	}
+
+	override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+		super.onViewCreated(view, savedInstanceState)
+		childFragmentManager.setFragmentResultListener(SyncHostDialogFragment.REQUEST_KEY, viewLifecycleOwner, this)
+	}
+
+	override fun onPreferenceTreeClick(preference: Preference): Boolean {
+		return when (preference.key) {
+			SyncSettings.KEY_HOST -> {
+				SyncHostDialogFragment.show(childFragmentManager)
+				true
+			}
+
+			else -> super.onPreferenceTreeClick(preference)
+		}
+	}
+
+	override fun onFragmentResult(requestKey: String, result: Bundle) {
+		bindHostSummary()
+	}
+
+	private fun bindHostSummary() {
+		val preference = findPreference<Preference>(SyncSettings.KEY_HOST) ?: return
+		preference.summary = syncSettings.host
+	}
+}

app/src/main/java/org/koitharu/kotatsu/settings/utils/AutoCompleteTextViewPreference.kt

@@ -10,6 +10,7 @@ import android.widget.EditText
 import androidx.annotation.ArrayRes
 import androidx.annotation.AttrRes
 import androidx.annotation.StyleRes
+import androidx.core.content.withStyledAttributes
 import androidx.preference.EditTextPreference
 import org.koitharu.kotatsu.R
 
@@ -25,6 +26,12 @@ class AutoCompleteTextViewPreference @JvmOverloads constructor(
 
 	init {
 		super.setOnBindEditTextListener(autoCompleteBindListener)
+		context.withStyledAttributes(attrs, R.styleable.AutoCompleteTextViewPreference, defStyleAttr, defStyleRes) {
+			val entriesId = getResourceId(R.styleable.AutoCompleteTextViewPreference_android_entries, 0)
+			if (entriesId != 0) {
+				setEntries(entriesId)
+			}
+		}
 	}
 
 	fun setEntries(@ArrayRes arrayResId: Int) {

app/src/main/java/org/koitharu/kotatsu/sync/data/SyncAuthApi.kt

@@ -1,11 +1,9 @@
 package org.koitharu.kotatsu.sync.data
 
-import android.content.Context
+import dagger.Reusable
-import dagger.hilt.android.qualifiers.ApplicationContext
 import okhttp3.OkHttpClient
 import okhttp3.Request
 import org.json.JSONObject
-import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.core.exceptions.SyncApiException
 import org.koitharu.kotatsu.parsers.util.await
 import org.koitharu.kotatsu.parsers.util.parseJson
@@ -13,19 +11,17 @@ import org.koitharu.kotatsu.parsers.util.removeSurrounding
 import org.koitharu.kotatsu.utils.ext.toRequestBody
 import javax.inject.Inject
 
+@Reusable
 class SyncAuthApi @Inject constructor(
-	@ApplicationContext context: Context,
 	private val okHttpClient: OkHttpClient,
 ) {
 
-	private val baseUrl = context.getString(R.string.url_sync_server)
+	suspend fun authenticate(host: String, email: String, password: String): String {
-
-	suspend fun authenticate(email: String, password: String): String {
 		val body = JSONObject(
 			mapOf("email" to email, "password" to password),
 		).toRequestBody()
 		val request = Request.Builder()
-			.url("$baseUrl/auth")
+			.url("http://$host/auth")
 			.post(body)
 			.build()
 		val response = okHttpClient.newCall(request).await()

app/src/main/java/org/koitharu/kotatsu/sync/data/SyncAuthenticator.kt

@@ -13,6 +13,7 @@ import org.koitharu.kotatsu.R
 class SyncAuthenticator(
 	context: Context,
 	private val account: Account,
+	private val syncSettings: SyncSettings,
 	private val authApi: SyncAuthApi,
 ) : Authenticator {
 
@@ -30,6 +31,7 @@ class SyncAuthenticator(
 	private fun tryRefreshToken() = runCatching {
 		runBlocking {
 			authApi.authenticate(
+				syncSettings.host,
 				account.name,
 				accountManager.getPassword(account),
 			)

app/src/main/java/org/koitharu/kotatsu/sync/data/SyncSettings.kt

@@ -0,0 +1,46 @@
+package org.koitharu.kotatsu.sync.data
+
+import android.accounts.Account
+import android.accounts.AccountManager
+import android.content.Context
+import androidx.annotation.WorkerThread
+import dagger.Reusable
+import dagger.hilt.android.qualifiers.ApplicationContext
+import org.koitharu.kotatsu.R
+import org.koitharu.kotatsu.utils.ext.ifNullOrEmpty
+import javax.inject.Inject
+
+@Reusable
+class SyncSettings(
+	context: Context,
+	private val account: Account?,
+) {
+
+	@Inject
+	constructor(@ApplicationContext context: Context) : this(
+		context,
+		AccountManager.get(context)
+			.getAccountsByType(context.getString(R.string.account_type_sync))
+			.firstOrNull(),
+	)
+
+	private val accountManager = AccountManager.get(context)
+	private val defaultHost = context.getString(R.string.sync_host_default)
+
+	@get:WorkerThread
+	@set:WorkerThread
+	var host: String
+		get() = account?.let {
+			accountManager.getUserData(it, KEY_HOST)
+		}.ifNullOrEmpty { defaultHost }
+		set(value) {
+			account?.let {
+				accountManager.setUserData(it, KEY_HOST, value)
+			}
+		}
+
+	companion object {
+
+		const val KEY_HOST = "host"
+	}
+}

app/src/main/java/org/koitharu/kotatsu/sync/domain/SyncAuthResult.kt

@@ -1,6 +1,7 @@
 package org.koitharu.kotatsu.sync.domain
 
 class SyncAuthResult(
+	val host: String,
 	val email: String,
 	val password: String,
 	val token: String,
@@ -12,15 +13,15 @@ class SyncAuthResult(
 
 		other as SyncAuthResult
 
+		if (host != other.host) return false
 		if (email != other.email) return false
 		if (password != other.password) return false
-		if (token != other.token) return false
+		return token == other.token
-
-		return true
 	}
 
 	override fun hashCode(): Int {
-		var result = email.hashCode()
+		var result = host.hashCode()
+		result = 31 * result + email.hashCode()
 		result = 31 * result + password.hashCode()
 		result = 31 * result + token.hashCode()
 		return result

app/src/main/java/org/koitharu/kotatsu/sync/domain/SyncHelper.kt

@@ -26,6 +26,7 @@ import org.koitharu.kotatsu.parsers.util.json.mapJSONTo
 import org.koitharu.kotatsu.sync.data.SyncAuthApi
 import org.koitharu.kotatsu.sync.data.SyncAuthenticator
 import org.koitharu.kotatsu.sync.data.SyncInterceptor
+import org.koitharu.kotatsu.sync.data.SyncSettings
 import org.koitharu.kotatsu.utils.GZipInterceptor
 import org.koitharu.kotatsu.utils.ext.parseJsonOrNull
 import org.koitharu.kotatsu.utils.ext.toContentValues
@@ -41,18 +42,20 @@ private const val FIELD_TIMESTAMP = "timestamp"
 @WorkerThread
 class SyncHelper(
 	context: Context,
-	account: Account,
+	private val account: Account,
 	private val provider: ContentProviderClient,
 ) {
 
 	private val authorityHistory = context.getString(R.string.sync_authority_history)
 	private val authorityFavourites = context.getString(R.string.sync_authority_favourites)
+	private val settings = SyncSettings(context, account)
 	private val httpClient = OkHttpClient.Builder()
-		.authenticator(SyncAuthenticator(context, account, SyncAuthApi(context, OkHttpClient())))
+		.authenticator(SyncAuthenticator(context, account, settings, SyncAuthApi(OkHttpClient())))
 		.addInterceptor(SyncInterceptor(context, account))
 		.addInterceptor(GZipInterceptor())
 		.build()
-	private val baseUrl = context.getString(R.string.url_sync_server)
+	private val baseUrl: String
+		get() = "http://${settings.host}"
 	private val defaultGcPeriod: Long // gc period if sync enabled
 		get() = TimeUnit.DAYS.toMillis(4)
 

app/src/main/java/org/koitharu/kotatsu/sync/ui/SyncAuthActivity.kt

@@ -11,8 +11,8 @@ import android.widget.Button
 import androidx.activity.OnBackPressedCallback
 import androidx.activity.viewModels
 import androidx.core.graphics.Insets
-import androidx.core.view.isGone
 import androidx.core.view.isVisible
+import androidx.fragment.app.FragmentResultListener
 import androidx.transition.Fade
 import androidx.transition.TransitionManager
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
@@ -20,12 +20,13 @@ import dagger.hilt.android.AndroidEntryPoint
 import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.base.ui.BaseActivity
 import org.koitharu.kotatsu.databinding.ActivitySyncAuthBinding
+import org.koitharu.kotatsu.sync.data.SyncSettings
 import org.koitharu.kotatsu.sync.domain.SyncAuthResult
 import org.koitharu.kotatsu.utils.ext.getDisplayMessage
 import org.koitharu.kotatsu.utils.ext.getParcelableExtraCompat
 
 @AndroidEntryPoint
-class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickListener {
+class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickListener, FragmentResultListener {
 
 	private var accountAuthenticatorResponse: AccountAuthenticatorResponse? = null
 	private var resultBundle: Bundle? = null
@@ -43,6 +44,8 @@ class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickLi
 		binding.buttonNext.setOnClickListener(this)
 		binding.buttonBack.setOnClickListener(this)
 		binding.buttonDone.setOnClickListener(this)
+		binding.layoutProgress.setOnClickListener(this)
+		binding.buttonSettings.setOnClickListener(this)
 		binding.editEmail.addTextChangedListener(EmailTextWatcher(binding.buttonNext))
 		binding.editPassword.addTextChangedListener(PasswordTextWatcher(binding.buttonDone))
 
@@ -52,6 +55,7 @@ class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickLi
 		viewModel.onError.observe(this, ::onError)
 		viewModel.isLoading.observe(this, ::onLoadingStateChanged)
 
+		supportFragmentManager.setFragmentResultListener(SyncHostDialogFragment.REQUEST_KEY, this, this)
 		pageBackCallback.update()
 	}
 
@@ -73,12 +77,14 @@ class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickLi
 			}
 
 			R.id.button_next -> {
-				binding.switcher.showNext()
+				binding.groupLogin.isVisible = false
+				binding.groupPassword.isVisible = true
 				pageBackCallback.update()
 			}
 
 			R.id.button_back -> {
-				binding.switcher.showPrevious()
+				binding.groupPassword.isVisible = false
+				binding.groupLogin.isVisible = true
 				pageBackCallback.update()
 			}
 
@@ -88,9 +94,18 @@ class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickLi
 					password = binding.editPassword.text.toString(),
 				)
 			}
+
+			R.id.button_settings -> {
+				SyncHostDialogFragment.show(supportFragmentManager)
+			}
 		}
 	}
 
+	override fun onFragmentResult(requestKey: String, result: Bundle) {
+		val host = result.getString(SyncHostDialogFragment.KEY_HOST) ?: return
+		viewModel.host.value = host
+	}
+
 	override fun finish() {
 		accountAuthenticatorResponse?.let { response ->
 			resultBundle?.also {
@@ -105,7 +120,6 @@ class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickLi
 			return
 		}
 		TransitionManager.beginDelayedTransition(binding.root, Fade())
-		binding.switcher.isGone = isLoading
 		binding.layoutProgress.isVisible = isLoading
 		pageBackCallback.update()
 	}
@@ -121,8 +135,10 @@ class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickLi
 	private fun onTokenReceived(authResult: SyncAuthResult) {
 		val am = AccountManager.get(this)
 		val account = Account(authResult.email, getString(R.string.account_type_sync))
+		val userdata = Bundle(1)
+		userdata.putString(SyncSettings.KEY_HOST, authResult.host)
 		val result = Bundle()
-		if (am.addAccountExplicitly(account, authResult.password, Bundle())) {
+		if (am.addAccountExplicitly(account, authResult.password, userdata)) {
 			result.putString(AccountManager.KEY_ACCOUNT_NAME, account.name)
 			result.putString(AccountManager.KEY_ACCOUNT_TYPE, account.type)
 			result.putString(AccountManager.KEY_AUTHTOKEN, authResult.token)
@@ -168,12 +184,13 @@ class SyncAuthActivity : BaseActivity<ActivitySyncAuthBinding>(), View.OnClickLi
 	private inner class PageBackCallback : OnBackPressedCallback(false) {
 
 		override fun handleOnBackPressed() {
-			binding.switcher.showPrevious()
+			binding.groupLogin.isVisible = true
+			binding.groupPassword.isVisible = false
 			update()
 		}
 
 		fun update() {
-			isEnabled = binding.switcher.isVisible && binding.switcher.displayedChild > 0
+			isEnabled = !binding.layoutProgress.isVisible && binding.groupPassword.isVisible
 		}
 	}
 }

app/src/main/java/org/koitharu/kotatsu/sync/ui/SyncAuthViewModel.kt

@@ -1,24 +1,34 @@
 package org.koitharu.kotatsu.sync.ui
 
+import android.content.Context
+import androidx.lifecycle.MutableLiveData
 import dagger.hilt.android.lifecycle.HiltViewModel
+import dagger.hilt.android.qualifiers.ApplicationContext
 import kotlinx.coroutines.Dispatchers
+import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.base.ui.BaseViewModel
 import org.koitharu.kotatsu.sync.data.SyncAuthApi
 import org.koitharu.kotatsu.sync.domain.SyncAuthResult
 import org.koitharu.kotatsu.utils.SingleLiveEvent
+import org.koitharu.kotatsu.utils.ext.ifNullOrEmpty
 import javax.inject.Inject
 
 @HiltViewModel
 class SyncAuthViewModel @Inject constructor(
+	@ApplicationContext context: Context,
 	private val api: SyncAuthApi,
 ) : BaseViewModel() {
 
 	val onTokenObtained = SingleLiveEvent<SyncAuthResult>()
+	val host = MutableLiveData("")
+
+	private val defaultHost = context.getString(R.string.sync_host_default)
 
 	fun obtainToken(email: String, password: String) {
+		val hostValue = host.value.ifNullOrEmpty { defaultHost }
 		launchLoadingJob(Dispatchers.Default) {
-			val token = api.authenticate(email, password)
+			val token = api.authenticate(hostValue, email, password)
-			val result = SyncAuthResult(email, password, token)
+			val result = SyncAuthResult(host.value.orEmpty(), email, password, token)
 			onTokenObtained.emitCall(result)
 		}
 	}

app/src/main/java/org/koitharu/kotatsu/sync/ui/SyncHostDialogFragment.kt

@@ -0,0 +1,79 @@
+package org.koitharu.kotatsu.sync.ui
+
+import android.content.DialogInterface
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.view.ViewGroup.MarginLayoutParams
+import android.widget.ArrayAdapter
+import androidx.core.os.bundleOf
+import androidx.core.view.updateLayoutParams
+import androidx.fragment.app.FragmentManager
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
+import dagger.hilt.android.AndroidEntryPoint
+import org.koitharu.kotatsu.R
+import org.koitharu.kotatsu.base.ui.AlertDialogFragment
+import org.koitharu.kotatsu.databinding.PreferenceDialogAutocompletetextviewBinding
+import org.koitharu.kotatsu.settings.DomainValidator
+import org.koitharu.kotatsu.sync.data.SyncSettings
+import javax.inject.Inject
+
+@AndroidEntryPoint
+class SyncHostDialogFragment : AlertDialogFragment<PreferenceDialogAutocompletetextviewBinding>(),
+	DialogInterface.OnClickListener {
+
+	@Inject
+	lateinit var syncSettings: SyncSettings
+
+	override fun onInflateView(
+		inflater: LayoutInflater,
+		container: ViewGroup?
+	) = PreferenceDialogAutocompletetextviewBinding.inflate(inflater, container, false)
+
+	override fun onBuildDialog(builder: MaterialAlertDialogBuilder): MaterialAlertDialogBuilder {
+		return super.onBuildDialog(builder)
+			.setPositiveButton(android.R.string.ok, this)
+			.setNegativeButton(android.R.string.cancel, this)
+			.setCancelable(false)
+			.setTitle(R.string.server_address)
+	}
+
+	override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+		super.onViewCreated(view, savedInstanceState)
+		binding.message.updateLayoutParams<MarginLayoutParams> {
+			topMargin = view.resources.getDimensionPixelOffset(R.dimen.screen_padding)
+			bottomMargin = topMargin
+		}
+		binding.message.setText(R.string.sync_host_description)
+		val entries = view.resources.getStringArray(R.array.sync_host_list)
+		val editText = binding.edit
+		editText.setText(syncSettings.host)
+		editText.threshold = 0
+		editText.setAdapter(ArrayAdapter(view.context, android.R.layout.simple_spinner_dropdown_item, entries))
+		binding.dropdown.setOnClickListener {
+			editText.showDropDown()
+		}
+		DomainValidator().attachToEditText(editText)
+	}
+
+	override fun onClick(dialog: DialogInterface, which: Int) {
+		when (which) {
+			DialogInterface.BUTTON_POSITIVE -> {
+				val result = binding.edit.text?.toString().orEmpty()
+				syncSettings.host = result
+				parentFragmentManager.setFragmentResult(REQUEST_KEY, bundleOf(KEY_HOST to result))
+			}
+		}
+		dialog.dismiss()
+	}
+
+	companion object {
+
+		private const val TAG = "SyncHostDialogFragment"
+		const val REQUEST_KEY = "sync_host"
+		const val KEY_HOST = "host"
+
+		fun show(fm: FragmentManager) = SyncHostDialogFragment().show(fm, TAG)
+	}
+}

app/src/main/res/layout/activity_sync_auth.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout
+<androidx.constraintlayout.widget.ConstraintLayout
 	xmlns:android="http://schemas.android.com/apk/res/android"
 	xmlns:app="http://schemas.android.com/apk/res-auto"
 	xmlns:tools="http://schemas.android.com/tools"
@@ -10,9 +10,8 @@
 
 	<TextView
 		android:id="@+id/textView_title"
-		android:layout_width="match_parent"
+		android:layout_width="0dp"
 		android:layout_height="wrap_content"
-		android:layout_marginTop="8dp"
 		android:drawablePadding="16dp"
 		android:gravity="center_horizontal"
 		android:text="@string/sync_title"
@@ -23,40 +22,40 @@
 		app:layout_constraintStart_toStartOf="parent"
 		app:layout_constraintTop_toTopOf="parent" />
 
-	<ViewSwitcher
+	<ImageButton
-		android:id="@+id/switcher"
+		android:id="@+id/button_settings"
-		android:layout_width="match_parent"
+		android:layout_width="wrap_content"
-		android:layout_height="match_parent">
+		android:layout_height="wrap_content"
-
+		android:background="?selectableItemBackgroundBorderless"
-		<RelativeLayout
+		android:padding="4dp"
-			android:id="@+id/page_email"
+		app:layout_constraintEnd_toEndOf="parent"
-			android:layout_width="match_parent"
+		app:layout_constraintTop_toTopOf="parent"
-			android:layout_height="match_parent">
+		app:srcCompat="@drawable/ic_settings" />
 
 	<TextView
 		android:id="@+id/textView_subtitle"
 		android:layout_width="0dp"
 		android:layout_height="wrap_content"
-				android:layout_alignParentStart="true"
-				android:layout_alignParentTop="true"
-				android:layout_alignParentEnd="true"
 		android:layout_marginTop="12dp"
 		android:gravity="center_horizontal"
 		android:text="@string/email_enter_hint"
-				android:textAppearance="?textAppearanceSubtitle1" />
+		android:textAppearance="?textAppearanceSubtitle1"
+		app:layout_constraintEnd_toEndOf="parent"
+		app:layout_constraintStart_toStartOf="parent"
+		app:layout_constraintTop_toBottomOf="@id/textView_title" />
 
 	<com.google.android.material.textfield.TextInputLayout
 		android:id="@+id/layout_email"
 		style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
 		android:layout_width="0dp"
 		android:layout_height="wrap_content"
-				android:layout_below="@id/textView_subtitle"
-				android:layout_alignParentStart="true"
-				android:layout_alignParentEnd="true"
 		android:layout_marginTop="30dp"
 		app:errorIconDrawable="@null"
 		app:helperText="@string/sync_auth_hint"
-				app:hintEnabled="false">
+		app:hintEnabled="false"
+		app:layout_constraintEnd_toEndOf="parent"
+		app:layout_constraintStart_toStartOf="parent"
+		app:layout_constraintTop_toBottomOf="@id/textView_subtitle">
 
 		<com.google.android.material.textfield.TextInputEditText
 			android:id="@+id/edit_email"
@@ -76,52 +75,44 @@
 		style="@style/Widget.Material3.Button.OutlinedButton"
 		android:layout_width="wrap_content"
 		android:layout_height="wrap_content"
-				android:layout_alignParentStart="true"
+		android:text="@android:string/cancel"
-				android:layout_alignParentBottom="true"
+		app:layout_constraintBottom_toBottomOf="parent"
-				android:text="@android:string/cancel" />
+		app:layout_constraintStart_toStartOf="parent" />
 
 	<Button
 		android:id="@+id/button_next"
 		style="@style/Widget.Material3.Button.TonalButton"
-				android:layout_width="wrap_content"
+		android:layout_width="0dp"
 		android:layout_height="wrap_content"
-				android:layout_alignParentEnd="true"
-				android:layout_alignParentBottom="true"
 		android:enabled="false"
 		android:text="@string/next"
-				tools:ignore="RelativeOverlap" />
+		app:layout_constraintBottom_toBottomOf="parent"
-
+		app:layout_constraintEnd_toEndOf="parent" />
-		</RelativeLayout>
-
-		<RelativeLayout
-			android:id="@+id/page_password"
-			android:layout_width="match_parent"
-			android:layout_height="match_parent">
 
 	<TextView
 		android:id="@+id/textView_subtitle_2"
 		android:layout_width="0dp"
 		android:layout_height="wrap_content"
-				android:layout_alignParentStart="true"
-				android:layout_alignParentTop="true"
-				android:layout_alignParentEnd="true"
 		android:layout_marginTop="12dp"
 		android:gravity="center_horizontal"
 		android:text="@string/enter_password"
-				android:textAppearance="?textAppearanceSubtitle1" />
+		android:textAppearance="?textAppearanceSubtitle1"
+		app:layout_constraintEnd_toEndOf="parent"
+		app:layout_constraintStart_toStartOf="parent"
+		app:layout_constraintTop_toBottomOf="@id/textView_title" />
 
 	<com.google.android.material.textfield.TextInputLayout
 		android:id="@+id/layout_password"
 		style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
 		android:layout_width="0dp"
 		android:layout_height="wrap_content"
-				android:layout_below="@id/textView_subtitle_2"
-				android:layout_alignParentStart="true"
-				android:layout_alignParentEnd="true"
 		android:layout_marginTop="30dp"
 		app:endIconMode="password_toggle"
 		app:errorIconDrawable="@null"
-				app:hintEnabled="false">
+		app:hintEnabled="false"
+		app:layout_constraintEnd_toEndOf="parent"
+		app:layout_constraintStart_toStartOf="parent"
+		app:layout_constraintTop_toBottomOf="@id/textView_subtitle_2">
 
 		<com.google.android.material.textfield.TextInputEditText
 			android:id="@+id/edit_password"
@@ -142,31 +133,46 @@
 		style="@style/Widget.Material3.Button.OutlinedButton"
 		android:layout_width="wrap_content"
 		android:layout_height="wrap_content"
-				android:layout_alignParentStart="true"
+		android:text="@string/back"
-				android:layout_alignParentBottom="true"
+		app:layout_constraintBottom_toBottomOf="parent"
-				android:text="@string/back" />
+		app:layout_constraintStart_toStartOf="parent" />
 
 	<Button
 		android:id="@+id/button_done"
 		style="@style/Widget.Material3.Button.TonalButton"
 		android:layout_width="wrap_content"
 		android:layout_height="wrap_content"
-				android:layout_alignParentEnd="true"
-				android:layout_alignParentBottom="true"
 		android:enabled="false"
 		android:text="@string/done"
-				tools:ignore="RelativeOverlap" />
+		app:layout_constraintBottom_toBottomOf="parent"
+		app:layout_constraintEnd_toEndOf="parent" />
 
-		</RelativeLayout>
+	<androidx.constraintlayout.widget.Group
-	</ViewSwitcher>
+		android:id="@+id/group_login"
+		android:layout_width="wrap_content"
+		android:layout_height="wrap_content"
+		app:constraint_referenced_ids="textView_subtitle,button_cancel,button_next,layout_email" />
+
+	<androidx.constraintlayout.widget.Group
+		android:id="@+id/group_password"
+		android:layout_width="wrap_content"
+		android:layout_height="wrap_content"
+		android:visibility="gone"
+		app:constraint_referenced_ids="textView_subtitle_2,button_back,button_done,layout_password" />
 
 	<FrameLayout
 		android:id="@+id/layout_progress"
-		android:layout_width="match_parent"
+		android:layout_width="0dp"
-		android:layout_height="match_parent"
+		android:layout_height="0dp"
-		android:visibility="gone">
+		android:background="?android:windowBackground"
+		android:visibility="gone"
+		app:layout_constraintBottom_toBottomOf="parent"
+		app:layout_constraintEnd_toEndOf="parent"
+		app:layout_constraintStart_toStartOf="parent"
+		app:layout_constraintTop_toBottomOf="@id/textView_title">
 
 		<com.google.android.material.progressindicator.CircularProgressIndicator
+			android:id="@+id/circularProgressIndicator"
 			android:layout_width="wrap_content"
 			android:layout_height="wrap_content"
 			android:layout_gravity="center"
@@ -174,4 +180,4 @@
 
 	</FrameLayout>
 
-</LinearLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/values/attrs.xml

@@ -103,4 +103,8 @@
 		<attr name="cornerSizeBottomRight" />
 	</declare-styleable>
 
+	<declare-styleable name="AutoCompleteTextViewPreference">
+		<attr name="android:entries" />
+	</declare-styleable>
+
 </resources>

app/src/main/res/values/constants.xml

@@ -7,7 +7,7 @@
 	<string name="url_weblate" translatable="false">https://hosted.weblate.org/engage/kotatsu</string>
 	<string name="url_error_report" translatable="false">https://acra.kotatsu.app/report</string>
 	<string name="account_type_sync" translatable="false">org.kotatsu.sync</string>
-	<string name="url_sync_server" translatable="false">https://sync.kotatsu.app</string>
+	<string name="sync_host_default" translatable="false">sync.kotatsu.app</string>
 	<string name="shikimori_clientId" translatable="false">Mw6F0tPEOgyV7F9U9Twg50Q8SndMY7hzIOfXg0AX_XU</string>
 	<string name="shikimori_clientSecret" translatable="false">euBMt1GGRSDpVIFQVPxZrO7Kh6X4gWyv0dABuj4B-M8</string>
 	<string name="anilist_clientId" translatable="false">9887</string>
@@ -41,9 +41,13 @@
 		<item>block_nsfw</item>
 		<item>block_all</item>
 	</string-array>
-	<string-array name="values_network_policy">
+	<string-array name="values_network_policy" translatable="false">
 		<item>1</item>
 		<item>2</item>
 		<item>0</item>
 	</string-array>
+	<string-array name="sync_host_list" translatable="false">
+		<item>@string/sync_host_default</item>
+		<item>86.57.183.214:8081</item>
+	</string-array>
 </resources>

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

@@ -435,4 +435,7 @@
 	<string name="show_on_shelf">Show on the Shelf</string>
 	<string name="sync_auth_hint">You can sign in into an existing account or create a new one</string>
 	<string name="find_similar">Find similar</string>
+	<string name="sync_settings">Synchronization settings</string>
+	<string name="server_address">Server address</string>
+	<string name="sync_host_description">You can use a self-hosted synchronization server or a default one. Don\'t change this if you\'re not sure what you\'re doing.</string>
 </resources>

app/src/main/res/xml/authenticator_sync.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <account-authenticator
 	xmlns:android="http://schemas.android.com/apk/res/android"
-	android:accountPreferences="@xml/pref_sync"
+	android:accountPreferences="@xml/pref_sync_header"
 	android:accountType="@string/account_type_sync"
 	android:icon="@mipmap/ic_launcher_round"
 	android:label="@string/app_name" />

app/src/main/res/xml/pref_services.xml

@@ -10,6 +10,12 @@
 		android:summary="@string/sync_title"
 		android:title="@string/sync" />
 
+	<PreferenceScreen
+		android:enabled="false"
+		android:fragment="org.koitharu.kotatsu.settings.SyncSettingsFragment"
+		android:key="sync_settings"
+		android:title="@string/sync_settings" />
+
 	<PreferenceCategory android:title="@string/tracking">
 
 		<Preference

app/src/main/res/xml/pref_sync.xml

@@ -1,2 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
-<PreferenceScreen />
+<PreferenceScreen
+	xmlns:android="http://schemas.android.com/apk/res/android">
+
+	<Preference
+		android:key="host"
+		android:title="@string/server_address" />
+
+</PreferenceScreen>

app/src/main/res/xml/pref_sync_header.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PreferenceScreen
+	xmlns:android="http://schemas.android.com/apk/res/android">
+
+	<Preference android:title="@string/sync_settings">
+
+		<intent
+			android:action="android.intent.action.VIEW"
+			android:data="kotatsu://sync-settings" />
+	</Preference>
+
+</PreferenceScreen>