Add a new lib-i18n to make message translation easier (#16942)

* Add support to better internationalization with a new lib.

* Add info about `lib-i18n` in the contributing guide.

* Use lib-i18n in M+ as well.

* Change properties files to UTF-8.

CONTRIBUTING.md

@@ -257,6 +257,16 @@ dependencies {
 }
 ```
 
+#### I18n library
+
+[`lib-i18n`](https://github.com/tachiyomiorg/tachiyomi-extensions/tree/master/lib/i18n) is a library for handling internationalization in the sources. It allows loading `.properties` files with messages located under the `res/raw` folder of each extension, that can be used to translate strings under the source.
+
+```gradle
+dependencies {
+    implementation(project(':lib-i18n'))
+}
+```
+
 #### Additional dependencies
 
 If you find yourself needing additional functionality, you can add more dependencies to your `build.gradle` file.

lib/i18n/build.gradle.kts

@@ -0,0 +1,21 @@
+plugins {
+    id("com.android.library")
+    kotlin("android")
+}
+
+android {
+    compileSdk = AndroidConfig.compileSdk
+
+    defaultConfig {
+        minSdk = AndroidConfig.minSdk
+        targetSdk = AndroidConfig.targetSdk
+    }
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    compileOnly(libs.kotlin.stdlib)
+}

lib/i18n/src/main/AndroidManifest.xml

@@ -0,0 +1,2 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="eu.kanade.tachiyomi.lib.i18n" />

lib/i18n/src/main/java/eu/kanade/tachiyomi/lib/i18n/Intl.kt

@@ -0,0 +1,83 @@
+package eu.kanade.tachiyomi.lib.i18n
+
+import java.io.InputStreamReader
+import java.text.Collator
+import java.util.Locale
+import java.util.PropertyResourceBundle
+
+/**
+ * A simple wrapper to make internationalization easier to use in sources.
+ *
+ * Message files should be put at the `/res/raw` folder, with the name
+ * `messages_{iso_639_1}.properties`, where `iso_639_1` should be using
+ * snake case and be in lowercase.
+ *
+ * To edit the strings, use the official JetBrain's
+ * [Resource Bundle Editor plugin](https://plugins.jetbrains.com/plugin/17035-resource-bundle-editor).
+ *
+ * Make sure to configure Android Studio to save Properties files as UTF-8 as well.
+ * You can refer to this [documentation](https://www.jetbrains.com/help/idea/properties-files.html#1cbc434e)
+ * on how to do so.
+ */
+class Intl(
+    private val language: String,
+    private val baseLanguage: String,
+    private val availableLanguages: Set<String>,
+    private val classLoader: ClassLoader,
+    private val createMessageFileName: (String) -> String = { createDefaultMessageFileName(it) }
+) {
+
+    val chosenLanguage: String = when (language) {
+        in availableLanguages -> language
+        else -> baseLanguage
+    }
+
+    private val locale: Locale = Locale.forLanguageTag(chosenLanguage)
+
+    val collator: Collator = Collator.getInstance(locale)
+
+    private val baseBundle: PropertyResourceBundle by lazy { createBundle(baseLanguage) }
+
+    private val bundle: PropertyResourceBundle by lazy {
+        if (chosenLanguage == baseLanguage) baseBundle else createBundle(chosenLanguage)
+    }
+
+    /**
+     * Returns the string from the message file. If the [key] is not present
+     * in the current language, the English value will be returned. If the [key]
+     * is also not present in English, the [key] surrounded by brackets will be returned.
+     */
+    operator fun get(key: String): String = when {
+        bundle.containsKey(key) -> bundle.getString(key)
+        baseBundle.containsKey(key) -> baseBundle.getString(key)
+        else -> "[$key]"
+    }
+
+    fun languageDisplayName(localeCode: String): String =
+        Locale.forLanguageTag(localeCode)
+            .getDisplayName(locale)
+            .replaceFirstChar { if (it.isLowerCase()) it.titlecase(locale) else it.toString() }
+
+    /**
+     * Creates a [PropertyResourceBundle] instance from the language specified.
+     * The expected message file will be loaded from the `res/raw`.
+     *
+     * The [PropertyResourceBundle] is used directly instead of [java.util.ResourceBundle]
+     * because the later has issues with UTF-8 files in Java 8, which would need
+     * the message files to be saved in ISO-8859-1, making the file readability bad.
+     */
+    private fun createBundle(lang: String): PropertyResourceBundle {
+        val fileName = createMessageFileName(lang)
+        val fileContent = classLoader.getResourceAsStream(fileName)
+
+        return PropertyResourceBundle(InputStreamReader(fileContent, "UTF-8"))
+    }
+
+    companion object {
+        fun createDefaultMessageFileName(lang: String): String {
+            val langSnakeCase = lang.replace("-", "_").lowercase()
+
+            return "res/raw/messages_$langSnakeCase.properties"
+        }
+    }
+}

settings.gradle.kts

@@ -1,6 +1,6 @@
 include(":core")
 
-listOf("dataimage", "unpacker", "cryptoaes", "textinterceptor", "synchrony").forEach {
+listOf("dataimage", "unpacker", "cryptoaes", "textinterceptor", "synchrony", "i18n").forEach {
     include(":lib-$it")
     project(":lib-$it").projectDir = File("lib/$it")
 }

src/all/mangadex/build.gradle

@@ -6,8 +6,12 @@ ext {
     extName = 'MangaDex'
     pkgNameSuffix = 'all.mangadex'
     extClass = '.MangaDexFactory'
-    extVersionCode = 181
+    extVersionCode = 182
     isNsfw = true
 }
 
+dependencies {
+    implementation(project(":lib-i18n"))
+}
+
 apply from: "$rootDir/common.gradle"

src/all/mangadex/res/raw/messages_en.properties

@@ -0,0 +1,145 @@
+alternative_titles=Alternative titles:
+alternative_titles_in_description=Alternative titles in description
+alternative_titles_in_description_summary=Include a manga's alternative titles at the end of its description
+block_group_by_uuid=Block groups by UUID
+block_group_by_uuid_summary=Chapters from blocked groups will not show up in Latest or Manga feed. Enter as a Comma-separated list of group UUIDs
+block_uploader_by_uuid=Block uploader by UUID
+block_uploader_by_uuid_summary=Chapters from blocked uploaders will not show up in Latest or Manga feed. Enter as a Comma-separated list of uploader UUIDs
+content=Content
+content_gore=Gore
+content_rating=Content rating
+content_rating_erotica=Erotica
+content_rating_genre=Content rating: %s
+content_rating_pornographic=Pornographic
+content_rating_safe=Safe
+content_rating_suggestive=Suggestive
+content_sexual_violence=Sexual violence
+cover_quality=Cover quality
+cover_quality_low=Low
+cover_quality_medium=Medium
+cover_quality_original=Original
+data_saver=Data saver
+data_saver_summary=Enables smaller, more compressed images
+excluded_tags_mode=Excluded tags mode
+filter_original_languages=Filter original languages
+filter_original_languages_summary=Only show content that was originally published in the selected languages in both latest and browse
+format=Format
+format_adaptation=Adaptation
+format_anthology=Anthology
+format_award_winning=Award winning
+format_doujinshi=Doujinshi
+format_fan_colored=Fan colored
+format_full_color=Full color
+format_long_strip=Long strip
+format_official_colored=Official colored
+format_oneshot=Oneshot
+format_user_created=User created
+format_web_comic=Web comic
+format_yonkoma=4-Koma
+genre=Genre
+genre_action=Action
+genre_adventure=Adventure
+genre_boys_love=Boy's Love
+genre_comedy=Comedy
+genre_crime=Crime
+genre_drama=Drama
+genre_fantasy=Fantasy
+genre_girls_love=Girl's Love
+genre_historical=Historical
+genre_horror=Horror
+genre_isekai=Isekai
+genre_magical_girls=Magical girls
+genre_mecha=Mecha
+genre_medical=Medical
+genre_mystery=Mystery
+genre_philosophical=Philosophical
+genre_romance=Romance
+genre_sci_fi=Sci-Fi
+genre_slice_of_life=Slice of life
+genre_sports=Sports
+genre_superhero=Superhero
+genre_thriller=Thriller
+genre_tragedy=Tragedy
+genre_wuxia=Wuxia
+has_available_chapters=Has available chapters
+included_tags_mode=Included tags mode
+invalid_author_id=Not a valid author ID
+invalid_group_id=Not a valid group ID
+invalid_uuids=The text contains invalid UUIDs
+migrate_warning=Migrate this entry from MangaDex to MangaDex to update it
+mode_and=And
+mode_or=Or
+no_group=No Group
+no_series_in_list=No series in the list
+original_language=Original language
+original_language_filter_chinese=%s (Manhua)
+original_language_filter_japanese=%s (Manga)
+original_language_filter_korean=%s (Manhwa)
+publication_demographic=Publication demographic
+publication_demographic_josei=Josei
+publication_demographic_none=None
+publication_demographic_seinen=Seinen
+publication_demographic_shoujo=Shoujo
+publication_demographic_shounen=Shounen
+sort=Sort
+sort_alphabetic=Alphabetic
+sort_chapter_uploaded_at=Chapter uploaded at
+sort_content_created_at=Content created at
+sort_content_info_updated_at=Content info updated at
+sort_number_of_follows=Number of follows
+sort_rating=Rating
+sort_relevance=Relevance
+sort_year=Year
+standard_content_rating=Default content rating
+standard_content_rating_summary=Show content with the selected ratings by default
+standard_https_port=Use HTTPS port 443 only
+standard_https_port_summary=Enable to only request image servers that use port 443. This allows users with stricter firewall restrictions to access MangaDex images
+status=Status
+status_cancelled=Cancelled
+status_completed=Completed
+status_hiatus=Hiatus
+status_ongoing=Ongoing
+tags_mode=Tags mode
+theme=Theme
+theme_aliens=Aliens
+theme_animals=Animals
+theme_cooking=Cooking
+theme_crossdressing=Crossdressing
+theme_delinquents=Delinquents
+theme_demons=Demons
+theme_gender_swap=Genderswap
+theme_ghosts=Ghosts
+theme_gyaru=Gyaru
+theme_harem=Harem
+theme_incest=Incest
+theme_loli=Loli
+theme_mafia=Mafia
+theme_magic=Magic
+theme_martial_arts=Martial arts
+theme_military=Military
+theme_monster_girls=Monster girls
+theme_monsters=Monsters
+theme_music=Music
+theme_ninja=Ninja
+theme_office_workers=Office workers
+theme_police=Police
+theme_post_apocalyptic=Post-apocalyptic
+theme_psychological=Psychological
+theme_reincarnation=Reincarnation
+theme_reverse_harem=Reverse harem
+theme_samurai=Samurai
+theme_school_life=School life
+theme_shota=Shota
+theme_supernatural=Supernatural
+theme_survival=Survival
+theme_time_travel=Time travel
+theme_traditional_games=Traditional games
+theme_vampires=Vampires
+theme_video_games=Video games
+theme_villainess=Vilania
+theme_virtual_reality=Virtual reality
+theme_zombies=Zombies
+try_using_first_volume_cover=Attempt to use the first volume cover as cover
+try_using_first_volume_cover_summary=May need to manually refresh entries already in library. Otherwise, clear database to have new covers to show up.
+unable_to_process_chapter_request=Unable to process Chapter request. HTTP code: %d
+uploaded_by=Uploaded by %s