From b1fa9d1d2273a1f6687f0aac185f53095e5bbd5e Mon Sep 17 00:00:00 2001
From: Koitharu <nvasya95@gmail.com>
Date: Sat, 2 Dec 2023 15:02:48 +0200
Subject: [PATCH] Fix mapping local chapters #577

---
 .../kotatsu/details/data/MangaDetails.kt      | 25 +++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/app/src/main/kotlin/org/koitharu/kotatsu/details/data/MangaDetails.kt b/app/src/main/kotlin/org/koitharu/kotatsu/details/data/MangaDetails.kt
index cc68e0a6c..30c814b96 100644
--- a/app/src/main/kotlin/org/koitharu/kotatsu/details/data/MangaDetails.kt
+++ b/app/src/main/kotlin/org/koitharu/kotatsu/details/data/MangaDetails.kt
@@ -21,8 +21,7 @@ data class MangaDetails(
 	val branches: Set<String?>
 		get() = chapters.keys
 
-	val allChapters: List<MangaChapter>
-		get() = manga.chapters.orEmpty()
+	val allChapters: List<MangaChapter> by lazy { mergeChapters() }
 
 	val isLocal
 		get() = manga.isLocal
@@ -40,4 +39,26 @@ data class MangaDetails(
 		description = description,
 		isLoaded = isLoaded,
 	)
+
+	private fun mergeChapters(): List<MangaChapter> {
+		val chapters = manga.chapters
+		val localChapters = local?.manga?.chapters.orEmpty()
+		if (chapters.isNullOrEmpty()) {
+			return localChapters
+		}
+		val localMap = if (localChapters.isNotEmpty()) {
+			localChapters.associateByTo(LinkedHashMap(localChapters.size)) { it.id }
+		} else {
+			null
+		}
+		val result = ArrayList<MangaChapter>(chapters.size)
+		for (chapter in chapters) {
+			val local = localMap?.remove(chapter.id)
+			result += local ?: chapter
+		}
+		if (!localMap.isNullOrEmpty()) {
+			result.addAll(localMap.values)
+		}
+		return result
+	}
 }