Fix chapters duplicates

src/main/kotlin/org/koitharu/kotatsu/parsers/site/BatoToParser.kt

@@ -54,6 +54,7 @@ internal class BatoToParser(override val context: MangaLoaderContext) : MangaPar
 			when (sortOrder) {
 				SortOrder.UPDATED,
 				-> append("update.za")
+
 				SortOrder.POPULARITY -> append("views_a.za")
 				SortOrder.NEWEST -> append("create.za")
 				SortOrder.ALPHABETICAL -> append("title.az")
@@ -93,7 +94,7 @@ internal class BatoToParser(override val context: MangaLoaderContext) : MangaPar
 				?.selectFirst(".main")
 				?.children()
 				?.reversed()
-				?.mapIndexedNotNull { i, div ->
+				?.mapChapters { i, div ->
 					div.parseChapter(i)
 				}.orEmpty(),
 		)

src/main/kotlin/org/koitharu/kotatsu/parsers/site/ExHentaiParser.kt

@@ -158,7 +158,7 @@ internal class ExHentaiParser(
 				a.text().toIntOrNull() != null
 			}?.let { a ->
 				val count = a.text().toInt()
-				val chapters = ArrayList<MangaChapter>(count)
+				val chapters = ChaptersListBuilder(count)
 				for (i in 1..count) {
 					val url = "${manga.url}?p=${i - 1}"
 					chapters += MangaChapter(
@@ -172,7 +172,7 @@ internal class ExHentaiParser(
 						branch = null,
 					)
 				}
-				chapters
+				chapters.toList()
 			},
 		)
 	}

src/main/kotlin/org/koitharu/kotatsu/parsers/site/Madara5Parser.kt

@@ -125,7 +125,7 @@ abstract class Madara5Parser @InternalParsersApi constructor(
 	private suspend fun loadChapters(mangaId: Long): List<MangaChapter> {
 		val dateFormat = SimpleDateFormat("MMMM dd, HH:mm", sourceLocale ?: Locale.US)
 		val doc = context.httpGet("https://${getDomain()}/ajax-list-chapter?mangaID=$mangaId").parseHtml()
-		return doc.select("li.wp-manga-chapter").asReversed().mapIndexed { i, li ->
+		return doc.select("li.wp-manga-chapter").asReversed().mapChapters { i, li ->
 			val a = li.selectFirstOrThrow("a")
 			val href = a.attrAsRelativeUrl("href")
 			MangaChapter(

src/main/kotlin/org/koitharu/kotatsu/parsers/site/MadaraParser.kt

@@ -137,7 +137,7 @@ internal abstract class MadaraParser(
 				?.select("p")
 				?.filterNot { it.ownText().startsWith("A brief description") }
 				?.joinToString { it.html() },
-			chapters = root2.select("li").asReversed().mapIndexed { i, li ->
+			chapters = root2.select("li").asReversed().mapChapters { i, li ->
 				val a = li.selectFirst("a")
 				val href = a?.attrAsRelativeUrlOrNull("href") ?: parseFailed("Link is missing")
 				MangaChapter(
@@ -200,6 +200,7 @@ internal abstract class MadaraParser(
 					set(Calendar.MILLISECOND, 0)
 				}.timeInMillis
 			}
+
 			date.startsWith("today", ignoreCase = true) -> {
 				Calendar.getInstance().apply {
 					set(Calendar.HOUR_OF_DAY, 0)
@@ -208,6 +209,7 @@ internal abstract class MadaraParser(
 					set(Calendar.MILLISECOND, 0)
 				}.timeInMillis
 			}
+
 			date.contains(Regex("""\d(st|nd|rd|th)""")) -> {
 				// Clean date (e.g. 5th December 2019 to 5 December 2019) before parsing it
 				date.split(" ").map {
@@ -219,6 +221,7 @@ internal abstract class MadaraParser(
 				}
 					.let { dateFormat.tryParse(it.joinToString(" ")) }
 			}
+
 			else -> dateFormat.tryParse(date)
 		}
 	}
@@ -238,24 +241,28 @@ internal abstract class MadaraParser(
 				"dia",
 				"day",
 			).anyWordIn(date) -> cal.apply { add(Calendar.DAY_OF_MONTH, -number) }.timeInMillis
+
 			WordSet("jam", "saat", "heure", "hora", "hour").anyWordIn(date) -> cal.apply {
 				add(
 					Calendar.HOUR,
 					-number,
 				)
 			}.timeInMillis
+
 			WordSet("menit", "dakika", "min", "minute", "minuto").anyWordIn(date) -> cal.apply {
 				add(
 					Calendar.MINUTE,
 					-number,
 				)
 			}.timeInMillis
+
 			WordSet("detik", "segundo", "second").anyWordIn(date) -> cal.apply {
 				add(
 					Calendar.SECOND,
 					-number,
 				)
 			}.timeInMillis
+
 			WordSet("month").anyWordIn(date) -> cal.apply { add(Calendar.MONTH, -number) }.timeInMillis
 			WordSet("year").anyWordIn(date) -> cal.apply { add(Calendar.YEAR, -number) }.timeInMillis
 			else -> 0
@@ -270,12 +277,12 @@ internal abstract class MadaraParser(
 
 	private fun createRequestTemplate() =
 		(
-			"action=madara_load_more&page=1&template=madara-core%2Fcontent%2Fcontent-search&vars%5Bs%5D=&vars%5B" +
-				"orderby%5D=meta_value_num&vars%5Bpaged%5D=1&vars%5Btemplate%5D=search&vars%5Bmeta_query" +
-				"%5D%5B0%5D%5Brelation%5D=AND&vars%5Bmeta_query%5D%5Brelation%5D=OR&vars%5Bpost_type" +
-				"%5D=wp-manga&vars%5Bpost_status%5D=publish&vars%5Bmeta_key%5D=_latest_update&vars%5Border" +
-				"%5D=desc&vars%5Bmanga_archives_item_layout%5D=default"
-			).split('&')
+				"action=madara_load_more&page=1&template=madara-core%2Fcontent%2Fcontent-search&vars%5Bs%5D=&vars%5B" +
+						"orderby%5D=meta_value_num&vars%5Bpaged%5D=1&vars%5Btemplate%5D=search&vars%5Bmeta_query" +
+						"%5D%5B0%5D%5Brelation%5D=AND&vars%5Bmeta_query%5D%5Brelation%5D=OR&vars%5Bpost_type" +
+						"%5D=wp-manga&vars%5Bpost_status%5D=publish&vars%5Bmeta_key%5D=_latest_update&vars%5Border" +
+						"%5D=desc&vars%5Bmanga_archives_item_layout%5D=default"
+				).split('&')
 			.map {
 				val pos = it.indexOf('=')
 				it.substring(0, pos) to it.substring(pos + 1)
@@ -293,7 +300,8 @@ internal abstract class MadaraParser(
 	class KingManga(context: MangaLoaderContext) : MadaraParser(context, MangaSource.KINGMANGA, "king-manga.com")
 
 	@MangaSourceParser("MANGAHATACHI", "MangahaTachi", "ja")
-	class MangahaTachi(context: MangaLoaderContext) : MadaraParser(context, MangaSource.MANGAHATACHI, "mangahatachi.com")
+	class MangahaTachi(context: MangaLoaderContext) :
+		MadaraParser(context, MangaSource.MANGAHATACHI, "mangahatachi.com")
 
 	@MangaSourceParser("PIANMANGA", "PianManga", "en")
 	class PianManga(context: MangaLoaderContext) : MadaraParser(context, MangaSource.PIANMANGA, "pianmanga.com")
@@ -400,7 +408,8 @@ internal abstract class MadaraParser(
 	}
 
 	@MangaSourceParser("MANGA_DISTRICT", "Manga District", "en")
-	class MangaDistrict(context: MangaLoaderContext) : MadaraParser(context, MangaSource.MANGA_DISTRICT, "mangadistrict.com") {
+	class MangaDistrict(context: MangaLoaderContext) :
+		MadaraParser(context, MangaSource.MANGA_DISTRICT, "mangadistrict.com") {
 
 		override val tagPrefix = "publication-genre/"
 
@@ -408,7 +417,8 @@ internal abstract class MadaraParser(
 	}
 
 	@MangaSourceParser("HENTAI_4FREE", "Hentai4Free", "en")
-	class Hentai4Free(context: MangaLoaderContext) : MadaraParser(context, MangaSource.HENTAI_4FREE, "hentai4free.net") {
+	class Hentai4Free(context: MangaLoaderContext) :
+		MadaraParser(context, MangaSource.HENTAI_4FREE, "hentai4free.net") {
 
 		override val tagPrefix = "hentai-tag/"
 
@@ -437,7 +447,8 @@ internal abstract class MadaraParser(
 	}
 
 	@MangaSourceParser("ALLPORN_COMIC", "All Porn Comic", "en")
-	class AllPornComic(context: MangaLoaderContext) : MadaraParser(context, MangaSource.ALLPORN_COMIC, "allporncomic.com") {
+	class AllPornComic(context: MangaLoaderContext) :
+		MadaraParser(context, MangaSource.ALLPORN_COMIC, "allporncomic.com") {
 
 		override val tagPrefix = "porncomic-genre/"
 
@@ -488,7 +499,8 @@ internal abstract class MadaraParser(
 	}
 
 	@MangaSourceParser("MANGA_MANHUA", "Manga Manhua", "en")
-	class MangaManhua(context: MangaLoaderContext) : MadaraParser(context, MangaSource.MANGA_MANHUA, "mangamanhua.online")
+	class MangaManhua(context: MangaLoaderContext) :
+		MadaraParser(context, MangaSource.MANGA_MANHUA, "mangamanhua.online")
 
 	@MangaSourceParser("MANGA_247", "247MANGA", "en")
 	class Manga247(context: MangaLoaderContext) : MadaraParser(context, MangaSource.MANGA_247, "247manga.com") {

src/main/kotlin/org/koitharu/kotatsu/parsers/site/MangaInUaParser.kt

@@ -29,13 +29,14 @@ class MangaInUaParser(override val context: MangaLoaderContext) : MangaParser(Ma
 		val searchPage = (offset / 10f).toIntUp().inc()
 		val url = when {
 			!query.isNullOrEmpty() -> (
-				"/index.php?do=search" +
-					"&subaction=search" +
-					"&search_start=$searchPage" +
-					"&full_search=1" +
-					"&story=$query" +
-					"&titleonly=3"
-				).toAbsoluteUrl(getDomain())
+					"/index.php?do=search" +
+							"&subaction=search" +
+							"&search_start=$searchPage" +
+							"&full_search=1" +
+							"&story=$query" +
+							"&titleonly=3"
+					).toAbsoluteUrl(getDomain())
+
 			tags.isNullOrEmpty() -> "/mangas/page/$page".toAbsoluteUrl(getDomain())
 			tags.size == 1 -> "${tags.first().key}/page/$page"
 			tags.size > 1 -> throw IllegalArgumentException("This source supports only 1 genre")
@@ -90,16 +91,16 @@ class MangaInUaParser(override val context: MangaLoaderContext) : MangaParser(Ma
 			description = root.selectFirst("div.item__full-description")?.text(),
 			largeCoverUrl = root.selectFirst("div.item__full-sidebar--poster")?.selectFirst("img")
 				?.attrAsAbsoluteUrlOrNull("src"),
-			chapters = chapterNodes.mapNotNull { item ->
+			chapters = chapterNodes.mapChapters { _, item ->
 				val href = item?.selectFirst("a")?.attrAsRelativeUrlOrNull("href")
-					?: return@mapNotNull null
+					?: return@mapChapters null
 				val isAlternative = item.styleValueOrNull("background") != null
 				val name = item.selectFirst("a")?.text().orEmpty()
 				if (!isAlternative) i++
 				MangaChapter(
 					id = generateUid(href),
 					name = if (isAlternative) {
-						prevChapterName ?: return@mapNotNull null
+						prevChapterName ?: return@mapChapters null
 					} else {
 						prevChapterName = name
 						name

src/main/kotlin/org/koitharu/kotatsu/parsers/site/MangaLibParser.kt

@@ -92,7 +92,7 @@ internal open class MangaLibParser(
 		val chaptersDoc = context.httpGet("$fullUrl?section=chapters").parseHtml()
 		val scripts = chaptersDoc.select("script")
 		val dateFormat = SimpleDateFormat("yyy-MM-dd", Locale.US)
-		var chapters: ArrayList<MangaChapter>? = null
+		var chapters: ChaptersListBuilder? = null
 		scripts@ for (script in scripts) {
 			val raw = script.html().lines()
 			for (line in raw) {
@@ -100,7 +100,7 @@ internal open class MangaLibParser(
 					val json = JSONObject(line.substringAfter('=').substringBeforeLast(';'))
 					val list = json.getJSONObject("chapters").getJSONArray("list")
 					val total = list.length()
-					chapters = ArrayList(total)
+					chapters = ChaptersListBuilder(total)
 					for (i in 0 until total) {
 						val item = list.getJSONObject(i)
 						val chapterId = item.getLong("chapter_id")
@@ -111,7 +111,6 @@ internal open class MangaLibParser(
 							append(item.getInt("chapter_volume"))
 							append("/c")
 							append(item.getString("chapter_number"))
-							@Suppress("BlockingMethodInNonBlockingContext") // lint issue
 							append('/')
 							append(item.optString("chapter_string"))
 						}
@@ -160,7 +159,7 @@ internal open class MangaLibParser(
 				} ?: manga.tags,
 			isNsfw = isNsfw(doc),
 			description = info?.selectFirst("div.media-description__text")?.html(),
-			chapters = chapters,
+			chapters = chapters?.toList(),
 		)
 	}
 

src/main/kotlin/org/koitharu/kotatsu/parsers/site/MangaOwlParser.kt

@@ -38,12 +38,14 @@ internal class MangaOwlParser(override val context: MangaLoaderContext) : MangaP
 					append("/search/$page?search=")
 					append(query.urlEncoded())
 				}
+
 				!tags.isNullOrEmpty() -> {
 					for (tag in tags) {
 						append(tag.key)
 					}
 					append("/$page?type=${getAlternativeSortKey(sortOrder)}")
 				}
+
 				else -> {
 					append("/${getSortKey(sortOrder)}/$page")
 				}
@@ -110,7 +112,7 @@ internal class MangaOwlParser(override val context: MangaLoaderContext) : MangaP
 			state = parseStatus(info.select("p.fexi_header_para:contains(status)").first()?.ownText()),
 			tags = manga.tags + parsedTags,
 			chapters = table.select("div.table.table-chapter-list").select("li.list-group-item.chapter_list")
-				.asReversed().mapIndexed { i, li ->
+				.asReversed().mapChapters { i, li ->
 					val a = li.select("a")
 					val href = a.attr("data-href").ifEmpty {
 						parseFailed("Link is missing")

src/main/kotlin/org/koitharu/kotatsu/parsers/site/MangaTownParser.kt

@@ -45,6 +45,7 @@ internal class MangaTownParser(override val context: MangaLoaderContext) : Manga
 				}
 				"/search?name=${query.urlEncoded()}".toAbsoluteUrl(getDomain())
 			}
+
 			tags.isNullOrEmpty() -> "/directory/$page.htm$sortKey".toAbsoluteUrl(getDomain())
 			tags.size == 1 -> "/directory/${tags.first().key}/$page.htm$sortKey".toAbsoluteUrl(getDomain())
 			else -> tags.joinToString(
@@ -112,9 +113,9 @@ internal class MangaTownParser(override val context: MangaLoaderContext) : Manga
 				)
 			}.orEmpty(),
 			description = info?.getElementById("show")?.ownText(),
-			chapters = chaptersList?.mapIndexedNotNull { i, li ->
+			chapters = chaptersList?.mapChapters { i, li ->
 				val href = li.selectFirst("a")?.attrAsRelativeUrlOrNull("href")
-					?: return@mapIndexedNotNull null
+					?: return@mapChapters null
 				val name = li.select("span")
 					.filter { x -> x.className().isEmpty() }
 					.joinToString(" - ") { it.text() }.trim()

src/main/kotlin/org/koitharu/kotatsu/parsers/site/NicovideoSeigaParser.kt

@@ -47,7 +47,9 @@ class NicovideoSeigaParser(override val context: MangaLoaderContext) :
 		val url = when {
 			!query.isNullOrEmpty() -> return if (offset == 0) getSearchList(query, page) else emptyList()
 			tags.isNullOrEmpty() -> "https://$domain/manga/list?page=$page&sort=${getSortKey(sortOrder)}"
-			tags.size == 1 -> "https://$domain/manga/list?category=${tags.first().key}&page=$page&sort=${getSortKey(sortOrder)}"
+			tags.size == 1 -> "https://$domain/manga/list?category=${tags.first().key}&page=$page" +
+					"&sort=${getSortKey(sortOrder)}"
+
 			tags.size > 1 -> throw IllegalArgumentException("This source supports only 1 category")
 			else -> "https://$domain/manga/list?page=$page&sort=${getSortKey(sortOrder)}"
 		}
@@ -55,7 +57,8 @@ class NicovideoSeigaParser(override val context: MangaLoaderContext) :
 		val comicList = doc.body().select("#comic_list > ul > li") ?: parseFailed("Container not found")
 		val items = comicList.select("div > .description > div > div")
 		return items.mapNotNull { item ->
-			val href = item.selectFirst(".comic_icon > div > a")?.attrAsRelativeUrlOrNull("href") ?: return@mapNotNull null
+			val href =
+				item.selectFirst(".comic_icon > div > a")?.attrAsRelativeUrlOrNull("href") ?: return@mapNotNull null
 			val statusText = item.selectFirst(".mg_description_header > .mg_icon > .content_status > span")?.text()
 			Manga(
 				id = generateUid(href),
@@ -92,15 +95,17 @@ class NicovideoSeigaParser(override val context: MangaLoaderContext) :
 			.text()
 		return manga.copy(
 			description = contents.selectFirst("div.mg_work_detail > div > div.row > div.description_text")?.html(),
-			largeCoverUrl = contents.selectFirst("div.primaries > div.main_visual > a > img")?.attrAsAbsoluteUrlOrNull("src"),
+			largeCoverUrl = contents.selectFirst("div.primaries > div.main_visual > a > img")
+				?.attrAsAbsoluteUrlOrNull("src"),
 			state = when (statusText) {
 				STATUS_ONGOING -> MangaState.ONGOING
 				STATUS_FINISHED -> MangaState.FINISHED
 				else -> null
 			},
 			isNsfw = contents.select(".icon_adult").isNotEmpty(),
-			chapters = contents.select("#episode_list > ul > li").mapIndexedNotNull { i, li ->
-				val href = li.selectFirst("div > div.description > div.title > a")?.attrAsRelativeUrl("href") ?: parseFailed()
+			chapters = contents.select("#episode_list > ul > li").mapChapters { i, li ->
+				val href = li.selectFirst("div > div.description > div.title > a")
+					?.attrAsRelativeUrl("href") ?: parseFailed()
 				MangaChapter(
 					id = generateUid(href),
 					name = li.select("div > div.description > div.title > a").text(),
@@ -151,7 +156,8 @@ class NicovideoSeigaParser(override val context: MangaLoaderContext) :
 		val doc = context.httpGet("https://$domain/manga/search/?q=$query&page=$page&sort=score").parseHtml()
 		val root = doc.body().select(".search_result__item")
 		return root.mapNotNull { item ->
-			val href = item.selectFirst(".search_result__item__thumbnail > a")?.attrAsRelativeUrl("href") ?: parseFailed()
+			val href = item.selectFirst(".search_result__item__thumbnail > a")
+				?.attrAsRelativeUrl("href") ?: parseFailed()
 			Manga(
 				id = generateUid(href),
 				url = href,

src/main/kotlin/org/koitharu/kotatsu/parsers/site/NineMangaParser.kt

@@ -50,6 +50,7 @@ internal abstract class NineMangaParser(
 					append(query.urlEncoded())
 					append("&page=")
 				}
+
 				!tags.isNullOrEmpty() -> {
 					append("/search/?category_id=")
 					for (tag in tags) {
@@ -58,6 +59,7 @@ internal abstract class NineMangaParser(
 					}
 					append("&page=")
 				}
+
 				else -> {
 					append("/category/index_")
 				}
@@ -115,7 +117,7 @@ internal abstract class NineMangaParser(
 			description = infoRoot.getElementsByAttributeValue("itemprop", "description").first()
 				?.html()?.substringAfter("</b>"),
 			chapters = root.selectFirst("div.chapterbox")?.select("ul.sub_vol_ul > li")
-				?.asReversed()?.mapIndexed { i, li ->
+				?.asReversed()?.mapChapters { i, li ->
 					val a = li.selectFirst("a.chapter_list_a")
 					val href = a?.attrAsRelativeUrlOrNull("href")
 						?.replace("%20", " ") ?: parseFailed("Link not found")

src/main/kotlin/org/koitharu/kotatsu/parsers/site/RemangaParser.kt

@@ -141,7 +141,7 @@ internal class RemangaParser(
 					source = MangaSource.REMANGA,
 				)
 			},
-			chapters = chapters.mapIndexed { i, jo ->
+			chapters = chapters.mapChapters { i, jo ->
 				val id = jo.getLong("id")
 				val name = jo.getString("name").toTitleCase(Locale.ROOT)
 				val publishers = jo.optJSONArray("publishers")

src/main/kotlin/org/koitharu/kotatsu/parsers/site/grouple/GroupleParser.kt

@@ -161,8 +161,8 @@ internal abstract class GroupleParser(
 			author = root.selectFirst("a.person-link")?.text() ?: manga.author,
 			isNsfw = root.select(".alert-warning").any { it.ownText().contains(NSFW_ALERT) },
 			chapters = root.selectFirst("div.chapters-link")?.selectFirst("table")
-				?.select("tr:has(td > a)")?.asReversed()?.mapIndexedNotNull { i, tr ->
-					val a = tr.selectFirst("a") ?: return@mapIndexedNotNull null
+				?.select("tr:has(td > a)")?.asReversed()?.mapChapters { i, tr ->
+					val a = tr.selectFirst("a") ?: return@mapChapters null
 					val href = a.attrAsRelativeUrl("href")
 					var translators = ""
 					val translatorElement = a.attr("title")

src/main/kotlin/org/koitharu/kotatsu/parsers/site/multichan/ChanParser.kt

@@ -90,9 +90,9 @@ internal abstract class ChanParser(source: MangaSource) : MangaParser(source), M
 		return manga.copy(
 			description = root.getElementById("description")?.html()?.substringBeforeLast("<div"),
 			largeCoverUrl = root.getElementById("cover")?.absUrl("src"),
-			chapters = root.select("table.table_cha tr:gt(1)").reversed().mapIndexedNotNull { i, tr ->
+			chapters = root.select("table.table_cha tr:gt(1)").reversed().mapChapters { i, tr ->
 				val href = tr?.selectFirst("a")?.attrAsRelativeUrlOrNull("href")
-					?: return@mapIndexedNotNull null
+					?: return@mapChapters null
 				MangaChapter(
 					id = generateUid(href),
 					name = tr.selectFirst("a")?.text().orEmpty(),

src/main/kotlin/org/koitharu/kotatsu/parsers/site/multichan/YaoiChanParser.kt

@@ -8,6 +8,7 @@ import org.koitharu.kotatsu.parsers.model.Manga
 import org.koitharu.kotatsu.parsers.model.MangaChapter
 import org.koitharu.kotatsu.parsers.model.MangaSource
 import org.koitharu.kotatsu.parsers.util.attrAsRelativeUrl
+import org.koitharu.kotatsu.parsers.util.mapChapters
 import org.koitharu.kotatsu.parsers.util.parseHtml
 import org.koitharu.kotatsu.parsers.util.toAbsoluteUrl
 
@@ -25,7 +26,7 @@ internal class YaoiChanParser(override val context: MangaLoaderContext) : ChanPa
 			largeCoverUrl = root.getElementById("cover")?.absUrl("src"),
 			chapters = root.select("table.table_cha").flatMap { table ->
 				table.select("div.manga")
-			}.mapNotNull { it.selectFirst("a") }.reversed().mapIndexed { i, a ->
+			}.mapNotNull { it.selectFirst("a") }.reversed().mapChapters { i, a ->
 				val href = a.attrAsRelativeUrl("href")
 				MangaChapter(
 					id = generateUid(href),

src/main/kotlin/org/koitharu/kotatsu/parsers/util/Chapters.kt

@@ -0,0 +1,42 @@
+package org.koitharu.kotatsu.parsers.util
+
+import org.koitharu.kotatsu.parsers.InternalParsersApi
+import org.koitharu.kotatsu.parsers.model.MangaChapter
+
+@InternalParsersApi
+inline fun <T> Iterable<T>.mapChapters(transform: (index: Int, T) -> MangaChapter?): List<MangaChapter> {
+	val builder = ChaptersListBuilder(collectionSize())
+	var index = 0
+	for (item in this) {
+		if (builder.add(transform(index, item))) {
+			index++
+		}
+	}
+	return builder.toList()
+}
+
+@PublishedApi
+internal fun <T> Iterable<T>.collectionSize(): Int {
+	return if (this is Collection<*>) this.size else 10
+}
+
+@PublishedApi
+internal class ChaptersListBuilder(initialSize: Int) {
+
+	private val ids = HashSet<Long>(initialSize)
+	private val list = ArrayList<MangaChapter>(initialSize)
+
+	fun add(chapter: MangaChapter?): Boolean {
+		return chapter != null && ids.add(chapter.id) && list.add(chapter)
+	}
+
+	operator fun plusAssign(chapter: MangaChapter?) {
+		add(chapter)
+	}
+
+	fun reverse() {
+		list.reverse()
+	}
+
+	fun toList(): List<MangaChapter> = list
+}