Add option to group by langauge

Closes #1376

app/src/main/java/eu/kanade/tachiyomi/data/database/models/Category.kt

@@ -28,6 +28,8 @@ interface Category : Serializable {
 
     var sourceId: Long?
 
+    var langId: String?
+
     fun isAscending(): Boolean {
         return ((mangaSort?.minus('a') ?: 0) % 2) != 1
     }

app/src/main/java/eu/kanade/tachiyomi/data/database/models/CategoryImpl.kt

@@ -22,6 +22,8 @@ class CategoryImpl : Category {
 
     override var sourceId: Long? = null
 
+    override var langId: String? = null
+
     override fun equals(other: Any?): Boolean {
         if (this === other) return true
         if (other == null || javaClass != other.javaClass) return false

app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryController.kt

@@ -75,6 +75,7 @@ import eu.kanade.tachiyomi.ui.category.CategoryController
 import eu.kanade.tachiyomi.ui.category.ManageCategoryDialog
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_AUTHOR
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_DEFAULT
+import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_LANGUAGE
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_SOURCE
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_STATUS
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_TAG
@@ -506,6 +507,7 @@ class LibraryController(
         if (presenter.isLoggedIntoTracking) {
             groupItems.add(BY_TRACK_STATUS)
         }
+        groupItems.add(BY_LANGUAGE)
         if (presenter.allCategories.size > 1) {
             groupItems.add(UNGROUPED)
         }

app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryGroup.kt

@@ -10,6 +10,7 @@ object LibraryGroup {
     const val BY_STATUS = 3
     const val BY_TRACK_STATUS = 4
     const val BY_AUTHOR = 6
+    const val BY_LANGUAGE = 7
     const val UNGROUPED = 5
 
     fun groupTypeStringRes(type: Int, hasCategories: Boolean = true): Int {
@@ -19,6 +20,7 @@ object LibraryGroup {
             BY_SOURCE -> R.string.sources
             BY_TRACK_STATUS -> R.string.tracking_status
             BY_AUTHOR -> R.string.author
+            BY_LANGUAGE -> R.string.language
             UNGROUPED -> R.string.ungrouped
             else -> if (hasCategories) R.string.categories else R.string.ungrouped
         }
@@ -31,6 +33,7 @@ object LibraryGroup {
             BY_TRACK_STATUS -> R.drawable.ic_sync_24dp
             BY_SOURCE -> R.drawable.ic_browse_24dp
             BY_AUTHOR -> R.drawable.ic_author_24dp
+            BY_LANGUAGE -> R.drawable.ic_translate_24dp
             UNGROUPED -> R.drawable.ic_ungroup_24dp
             else -> R.drawable.ic_label_outline_24dp
         }

app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryHeaderHolder.kt

@@ -169,6 +169,9 @@ class LibraryHeaderHolder(val view: View, val adapter: LibraryCategoryAdapter) :
             val icon = adapter.sourceManager.get(category.sourceId!!)?.icon()
             icon?.setBounds(0, 0, 32.dpToPx, 32.dpToPx)
             binding.categoryTitle.setCompoundDrawablesRelative(icon, null, null, null)
+        } else if (category.langId != null) {
+            val icon = getFlagIcon(category.langId!!) ?: 0
+            binding.categoryTitle.setCompoundDrawablesRelativeWithIntrinsicBounds(0, 0, icon, 0)
         } else {
             binding.categoryTitle.setCompoundDrawablesRelative(null, null, null, null)
         }
@@ -190,7 +193,7 @@ class LibraryHeaderHolder(val view: View, val adapter: LibraryCategoryAdapter) :
                 binding.updateButton.isVisible = false
                 setSelection()
             }
-            category.id ?: -1 < 0 -> {
+            (category.id ?: -1) < 0 -> {
                 binding.collapseArrow.isVisible = false
                 binding.checkbox.isVisible = false
                 setRefreshing(false)
@@ -211,6 +214,24 @@ class LibraryHeaderHolder(val view: View, val adapter: LibraryCategoryAdapter) :
         }
     }
 
+    @SuppressLint("DiscouragedApi")
+    fun getFlagIcon(lang: String): Int? {
+        val flagId = itemView.resources.getIdentifier(
+            "ic_flag_${lang.replace("-", "_")}",
+            "drawable",
+            itemView.context.packageName,
+        ).takeIf { it != 0 } ?: (
+            if (lang.contains("-")) {
+                itemView.resources.getIdentifier(
+                    "ic_flag_${lang.split("-").first()}",
+                    "drawable",
+                    itemView.context.packageName,
+                ).takeIf { it != 0 }
+            } else null
+            )
+        return flagId
+    }
+
     fun setRefreshing(refreshing: Boolean) {
         binding.updateButton.isClickable = !refreshing
         if (refreshing) {

app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryPresenter.kt

@@ -22,6 +22,7 @@ import eu.kanade.tachiyomi.source.online.HttpSource
 import eu.kanade.tachiyomi.ui.base.presenter.BaseCoroutinePresenter
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_AUTHOR
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_DEFAULT
+import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_LANGUAGE
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_SOURCE
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_TAG
 import eu.kanade.tachiyomi.ui.library.LibraryGroup.BY_TRACK_STATUS
@@ -415,15 +416,15 @@ class LibraryPresenter(
     private fun setSourceLanguage(itemList: List<LibraryItem>) {
         val showLanguageBadges = preferences.languageBadge().get()
         for (item in itemList) {
-            item.sourceLanguage = if (showLanguageBadges) {
+            item.sourceLanguage = if (showLanguageBadges) getLanguage(item.manga) else null
-                if (item.manga.isLocal()) {
+        }
-                    LocalSource.getMangaLang(item.manga, context)
+    }
-                } else {
+
-                    sourceManager.get(item.manga.source)?.lang
+    private fun getLanguage(manga: Manga): String? {
-                }
+        return if (manga.isLocal()) {
-            } else {
+            LocalSource.getMangaLang(manga, context)
-                null
+        } else {
-            }
+            sourceManager.get(manga.source)?.lang
         }
     }
 
@@ -730,7 +731,25 @@ class LibraryPresenter(
                         }
                     }
                 }
-                else -> listOf(LibraryItem(manga, makeOrGetHeader(context.mapStatus(manga.status)), viewContext))
+                BY_LANGUAGE -> {
+                    val lang = getLanguage(manga)
+                    listOf(
+                        LibraryItem(
+                            manga,
+                            makeOrGetHeader(
+                                lang?.plus(langSplitter)?.plus(
+                                    run {
+                                        val locale = Locale.forLanguageTag(lang)
+                                        locale.getDisplayName(locale)
+                                            .replaceFirstChar { it.uppercase(locale) }
+                                    },
+                                ) ?: unknown,
+                            ),
+                            viewContext,
+                        ),
+                    )
+                }
+                else /* BY_STATUS */ -> listOf(LibraryItem(manga, makeOrGetHeader(context.mapStatus(manga.status)), viewContext))
             }
         }.flatten().toMutableList()
 
@@ -746,6 +765,10 @@ class LibraryPresenter(
                     val split = name.split(sourceSplitter)
                     name = split.first()
                     sourceId = split.last().toLongOrNull()
+                } else if (name.contains(langSplitter)) {
+                    val split = name.split(langSplitter)
+                    name = split.last()
+                    langId = split.first()
                 }
                 isHidden = getDynamicCategoryName(this) in hiddenDynamics
             }
@@ -764,7 +787,13 @@ class LibraryPresenter(
         headers.forEach { category ->
             val catId = category.id ?: return@forEach
             val headerItem =
-                tagItems[if (category.sourceId != null) "${category.name}$sourceSplitter${category.sourceId}" else category.name]
+                tagItems[
+                    when {
+                        category.sourceId != null -> "${category.name}$sourceSplitter${category.sourceId}"
+                        category.langId != null -> "${category.langId}$langSplitter${category.name}"
+                        else -> category.name
+                    },
+                ]
             if (category.isHidden) {
                 val mangaToRemove = items.filter { it.header.catId == catId }
                 val mergedTitle = mangaToRemove.joinToString("-") {
@@ -1052,8 +1081,7 @@ class LibraryPresenter(
 
     private fun getDynamicCategoryName(category: Category): String =
         groupType.toString() + dynamicCategorySplitter + (
-            category.sourceId?.toString()
+            category.sourceId?.toString() ?: category.langId ?: category.name
-                ?: category.name
             )
 
     fun toggleAllCategoryVisibility() {
@@ -1162,6 +1190,7 @@ class LibraryPresenter(
         private var lastLibraryItems: List<LibraryItem>? = null
         private var lastCategories: List<Category>? = null
         private const val sourceSplitter = "◘•◘"
+        private const val langSplitter = "⨼⨦⨠"
         private const val dynamicCategorySplitter = "▄╪\t▄╪\t▄"
 
         private val randomTags = arrayOf(0, 1, 2)

app/src/main/res/drawable/ic_translate_24dp.xml

@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="#000000"
+    android:viewportHeight="24" android:viewportWidth="24"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="@android:color/white" android:pathData="M12.87,15.07l-2.54,-2.51 0.03,-0.03c1.74,-1.94 2.98,-4.17 3.71,-6.53L17,6L17,4h-7L10,2L8,2v2L1,4v1.99h11.17C11.5,7.92 10.44,9.75 9,11.35 8.07,10.32 7.3,9.19 6.69,8h-2c0.73,1.63 1.73,3.17 2.98,4.56l-5.09,5.02L4,19l5,-5 3.11,3.11 0.76,-2.04zM18.5,10h-2L12,22h2l1.12,-3h4.75L21,22h2l-4.5,-12zM15.88,17l1.62,-4.33L19.12,17h-3.24z"/>
+</vector>

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

@@ -145,7 +145,7 @@
                     android:text="@string/language"
                     android:textColor="?attr/colorOnBackground"
                     app:checkedIconEnabled="false"
-                    app:chipIcon="@drawable/ic_language_24dp"
+                    app:chipIcon="@drawable/ic_translate_24dp"
                     app:chipIconEnabled="false"
                     app:chipIconTint="?attr/colorOnBackground"
                     app:chipStrokeColor="?attr/colorSecondary"