Actually compare chapter numbers as numbers when sorting (fixes #7247)

(cherry picked from commit da8669c826e6575a76751842bda3da59dc2f07c7)

app/src/main/java/eu/kanade/tachiyomi/ui/browse/migration/MigrationFlags.kt

@@ -20,8 +20,8 @@ object MigrationFlags {
     private const val CATEGORIES2 = 0x2
     private const val TRACK2 = 0x4
 
-	private val coverCache: CoverCache by injectLazy()
-	private val db: DatabaseHelper = Injekt.get()
+    private val coverCache: CoverCache by injectLazy()
+    private val db: DatabaseHelper = Injekt.get()
 
     val flags get() = arrayOf(CHAPTERS, CATEGORIES, TRACK, CUSTOM_COVER)
 
@@ -49,19 +49,19 @@ object MigrationFlags {
         return positions.fold(0) { accumulated, position -> accumulated or (1 shl position) }
     }
 
-	fun titles(manga: Manga?): Array<Int> {
-		val titles = arrayOf(R.string.chapters, R.string.categories).toMutableList()
-		if (manga != null) {
-			db.inTransaction {
-				if (db.getTracks(manga).executeAsBlocking().isNotEmpty()) {
-					titles.add(R.string.track)
-				}
+    fun titles(manga: Manga?): Array<Int> {
+        val titles = arrayOf(R.string.chapters, R.string.categories).toMutableList()
+        if (manga != null) {
+            db.inTransaction {
+                if (db.getTracks(manga).executeAsBlocking().isNotEmpty()) {
+                    titles.add(R.string.track)
+                }
 
-				if (manga.hasCustomCover(coverCache)) {
-					titles.add(R.string.custom_cover)
-				}
-			}
-		}
-			return titles.toTypedArray()
-	}
+                if (manga.hasCustomCover(coverCache)) {
+                    titles.add(R.string.custom_cover)
+                }
+            }
+        }
+        return titles.toTypedArray()
+    }
 }

app/src/main/java/eu/kanade/tachiyomi/util/chapter/ChapterSorter.kt

@@ -2,7 +2,6 @@ package eu.kanade.tachiyomi.util.chapter
 
 import eu.kanade.tachiyomi.data.database.models.Chapter
 import eu.kanade.tachiyomi.data.database.models.Manga
-import eu.kanade.tachiyomi.util.lang.compareToCaseInsensitiveNaturalOrder
 
 fun getChapterSort(manga: Manga, sortDescending: Boolean = manga.sortDescending()): (Chapter, Chapter) -> Int {
     return when (manga.sorting) {
@@ -11,13 +10,13 @@ fun getChapterSort(manga: Manga, sortDescending: Boolean = manga.sortDescending(
             false -> { c1, c2 -> c2.source_order.compareTo(c1.source_order) }
         }
         Manga.CHAPTER_SORTING_NUMBER -> when (sortDescending) {
-            true -> { c1, c2 -> c2.chapter_number.toString().compareToCaseInsensitiveNaturalOrder(c1.chapter_number.toString()) }
-            false -> { c1, c2 -> c1.chapter_number.toString().compareToCaseInsensitiveNaturalOrder(c2.chapter_number.toString()) }
+            true -> { c1, c2 -> c2.chapter_number.compareTo(c1.chapter_number) }
+            false -> { c1, c2 -> c1.chapter_number.compareTo(c2.chapter_number) }
         }
         Manga.CHAPTER_SORTING_UPLOAD_DATE -> when (sortDescending) {
             true -> { c1, c2 -> c2.date_upload.compareTo(c1.date_upload) }
             false -> { c1, c2 -> c1.date_upload.compareTo(c2.date_upload) }
         }
-        else -> throw NotImplementedError("Unimplemented sorting method")
+        else -> throw NotImplementedError("Invalid chapter sorting method: ${manga.sorting}")
     }
 }