Merge pull request #2493 from quran/use_coroutines_for_translations

Use coroutines instead of Rx for translations

app/src/main/java/com/quran/labs/androidquran/model/translation/TranslationModel.kt

@@ -10,7 +10,8 @@ import com.quran.labs.androidquran.database.DatabaseHandler
 import com.quran.labs.androidquran.database.DatabaseHandler.TextType
 import com.quran.labs.androidquran.util.QuranFileUtils
 import com.quran.mobile.di.qualifier.ApplicationContext
-import io.reactivex.rxjava3.core.Single
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
 import javax.inject.Inject
 
 @ActivityScope
@@ -20,7 +21,7 @@ class TranslationModel @Inject internal constructor(
   private val ayahMapper: AyahMapper
 ) {
 
-  fun getArabicFromDatabase(verses: VerseRange): Single<List<QuranText>> {
+  suspend fun getArabicFromDatabase(verses: VerseRange): List<QuranText> {
     return getVersesFromDatabase(
         verses,
         QuranDataProvider.QURAN_ARABIC_DATABASE,
@@ -29,17 +30,17 @@ class TranslationModel @Inject internal constructor(
     )
   }
 
-  fun getTranslationFromDatabase(verses: VerseRange, db: String): Single<List<QuranText>> {
+  suspend fun getTranslationFromDatabase(verses: VerseRange, db: String): List<QuranText> {
     return getVersesFromDatabase(verses, db, TextType.TRANSLATION, shouldMap = true)
   }
 
-  private fun getVersesFromDatabase(
+  private suspend fun getVersesFromDatabase(
     verses: VerseRange,
     database: String,
     @TextType type: Int,
     shouldMap: Boolean = false
-  ): Single<List<QuranText>> {
-    return Single.fromCallable {
+  ): List<QuranText> {
+    return withContext(Dispatchers.IO) {
       val databaseHandler = DatabaseHandler.getDatabaseHandler(appContext, database, quranFileUtils)
 
       if (shouldMap) {

app/src/main/java/com/quran/labs/androidquran/presenter/translation/BaseTranslationPresenter.kt

@@ -5,7 +5,6 @@ import com.quran.data.model.QuranText
 import com.quran.data.model.SuraAyah
 import com.quran.data.model.SuraAyahIterator
 import com.quran.data.model.VerseRange
-import com.quran.labs.androidquran.common.LocalTranslationDisplaySort
 import com.quran.labs.androidquran.common.QuranAyahInfo
 import com.quran.labs.androidquran.common.TranslationMetadata
 import com.quran.labs.androidquran.database.TranslationsDBAdapter
@@ -14,12 +13,12 @@ import com.quran.labs.androidquran.presenter.Presenter
 import com.quran.labs.androidquran.util.QuranSettings
 import com.quran.labs.androidquran.util.TranslationUtil
 import com.quran.mobile.translation.model.LocalTranslation
-import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers
-import io.reactivex.rxjava3.core.Observable
-import io.reactivex.rxjava3.core.Single
-import io.reactivex.rxjava3.disposables.Disposable
-import io.reactivex.rxjava3.schedulers.Schedulers
-import java.util.Collections
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.async
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.withContext
 
 open class BaseTranslationPresenter<T : Any> internal constructor(
     private val translationModel: TranslationModel,
@@ -30,46 +29,57 @@ open class BaseTranslationPresenter<T : Any> internal constructor(
   private val translationMap: MutableMap<String, LocalTranslation> = HashMap()
 
   var translationScreen: T? = null
-  var disposable: Disposable? = null
-
-  fun getVerses(getArabic: Boolean,
-                translationsFileNames: List<String>,
-                verseRange: VerseRange
-  ): Single<ResultHolder> {
-
-    val translations = translationsAdapter.legacyGetTranslations()
-    val sortedTranslations: List<LocalTranslation> = ArrayList(translations)
-    Collections.sort(sortedTranslations, LocalTranslationDisplaySort())
-
-    val orderedTranslationsFileNames = sortedTranslations
-      .filter { translationsFileNames.contains(it.filename) }
-      .map { it.filename }
-
-    // get all the translations for these verses, using a source of the list of ordered active translations
-    val source = Observable.fromIterable(orderedTranslationsFileNames)
-
-    val translationsObservable =
-      source.concatMapEager { db ->
-        translationModel.getTranslationFromDatabase(verseRange, db)
-          .map { texts -> ensureProperTranslations(verseRange, texts) }
-          .onErrorReturnItem(ArrayList())
-          .toObservable()
+
+  suspend fun getVerses(
+    getArabic: Boolean,
+    translationsFileNames: List<String>,
+    verseRange: VerseRange
+  ): ResultHolder {
+    return withContext(Dispatchers.IO) {
+      val translations = translationsAdapter.getTranslations().first()
+      val sortedTranslations: List<LocalTranslation> = translations.sortedBy { it.displayOrder }
+
+      val orderedTranslationsFileNames = sortedTranslations
+        .filter { translationsFileNames.contains(it.filename) }
+        .map { it.filename }
+
+      val job = SupervisorJob()
+      // get all the translations for these verses, using a source of the list of ordered active translations
+      val translationData = orderedTranslationsFileNames.map {
+        async(job) {
+          val initialTexts = translationModel.getTranslationFromDatabase(verseRange, it)
+          ensureProperTranslations(verseRange, initialTexts)
+        }
+      }
+
+      val arabic = async(job) {
+        if (getArabic) {
+          translationModel.getArabicFromDatabase(verseRange)
+        } else {
+          emptyList()
+        }
+      }
+
+      val arabicText =
+        try {
+          arabic.await()
+        } catch (e: Exception) {
+          emptyList()
+        }
+
+      val translationTexts = translationData.map { deferred ->
+        try {
+          deferred.await()
+        } catch (e: Exception) {
+          emptyList()
+        }
       }
-        .toList()
-    val arabicObservable = if (!getArabic)
-      Single.just(ArrayList())
-    else
-      translationModel.getArabicFromDatabase(verseRange).onErrorReturnItem(ArrayList())
-    return Single.zip(
-      arabicObservable, translationsObservable, getTranslationMapSingle()
-    ) { arabic: List<QuranText>,
-        texts: List<List<QuranText>>,
-        map: Map<String, LocalTranslation> ->
-      val translationInfos = getTranslations(orderedTranslationsFileNames, map)
-      val ayahInfo = combineAyahData(verseRange, arabic, texts, translationInfos)
+      val translationMap = getTranslationMap()
+
+      val translationInfos = getTranslations(orderedTranslationsFileNames, translationMap)
+      val ayahInfo = combineAyahData(verseRange, arabicText, translationTexts, translationInfos)
       ResultHolder(translationInfos, ayahInfo)
     }
-      .subscribeOn(Schedulers.io())
   }
 
   fun getTranslations(quranSettings: QuranSettings): List<String> {
@@ -174,18 +184,19 @@ open class BaseTranslationPresenter<T : Any> internal constructor(
     return texts
   }
 
-  private fun getTranslationMapSingle(): Single<Map<String, LocalTranslation>> {
-    return if (this.translationMap.isEmpty()) {
-          Single.fromCallable { translationsAdapter.legacyGetTranslations() }
-            .map { translations -> translations.associateBy { it.filename } }
-            .subscribeOn(Schedulers.io())
-            .observeOn(AndroidSchedulers.mainThread())
-            .doOnSuccess { map ->
-              this.translationMap.clear()
-              this.translationMap.putAll(map)
-            }
-    } else {
-      Single.just(this.translationMap)
+  private suspend fun getTranslationMap(): Map<String, LocalTranslation> {
+    val currentTranslationMap = translationMap
+    return withContext(Dispatchers.IO) {
+      if (currentTranslationMap.isEmpty()) {
+        val updatedTranslations = translationsAdapter.getTranslations()
+          .map { it.associateBy { it.filename } }
+          .first()
+        translationMap.clear()
+        translationMap.putAll(updatedTranslations)
+        updatedTranslations
+      } else {
+        currentTranslationMap
+      }
     }
   }
 
@@ -198,6 +209,5 @@ open class BaseTranslationPresenter<T : Any> internal constructor(
 
   override fun unbind(what: T) {
     translationScreen = null
-    disposable?.dispose()
   }
 }

app/src/main/java/com/quran/labs/androidquran/presenter/translation/InlineTranslationPresenter.kt

@@ -9,11 +9,11 @@ import com.quran.labs.androidquran.presenter.translationlist.TranslationListPres
 import com.quran.labs.androidquran.util.QuranSettings
 import com.quran.labs.androidquran.util.TranslationUtil
 import com.quran.mobile.translation.model.LocalTranslation
-import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers
-import io.reactivex.rxjava3.observers.DisposableSingleObserver
+import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.MainScope
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
+import kotlinx.coroutines.withContext
 import javax.inject.Inject
 
 class InlineTranslationPresenter @Inject constructor(
@@ -38,17 +38,11 @@ class InlineTranslationPresenter @Inject constructor(
       .launchIn(scope)
   }
 
-  fun refresh(verseRange: VerseRange) {
-    disposable?.dispose()
-    disposable = getVerses(false, getTranslations(quranSettings), verseRange)
-      .observeOn(AndroidSchedulers.mainThread())
-      .subscribeWith(object : DisposableSingleObserver<ResultHolder>() {
-        override fun onSuccess(result: ResultHolder) {
-          translationScreen?.setVerses(result.translations, result.ayahInformation)
-        }
-
-        override fun onError(e: Throwable) {}
-      })
+  suspend fun refresh(verseRange: VerseRange) {
+    val result = withContext(Dispatchers.IO) {
+      getVerses(false, getTranslations(quranSettings), verseRange)
+    }
+    translationScreen?.setVerses(result.translations, result.ayahInformation)
   }
 
   override fun bind(what: TranslationScreen) {

app/src/main/java/com/quran/labs/androidquran/presenter/translation/TranslationManagerPresenter.kt

@@ -2,7 +2,6 @@ package com.quran.labs.androidquran.presenter.translation
 
 import android.content.Context
 import android.util.Pair
-import androidx.annotation.VisibleForTesting
 import com.quran.labs.androidquran.dao.translation.Translation
 import com.quran.labs.androidquran.dao.translation.TranslationItem
 import com.quran.labs.androidquran.dao.translation.TranslationList
@@ -43,8 +42,7 @@ open class TranslationManagerPresenter @Inject internal constructor(
   private val translationsDBAdapter: TranslationsDBAdapter,
   private val quranFileUtils: QuranFileUtils
 ) {
-  @VisibleForTesting
-  var host: String = Constants.HOST
+  internal var host: String = Constants.HOST
 
   private val scope = MainScope()
 

app/src/main/java/com/quran/labs/androidquran/presenter/translation/TranslationPresenter.kt

@@ -11,43 +11,61 @@ import com.quran.mobile.translation.model.LocalTranslation
 import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers
 import io.reactivex.rxjava3.core.Observable
 import io.reactivex.rxjava3.observers.DisposableObserver
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.MainScope
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.flow.asFlow
+import kotlinx.coroutines.flow.flatMapLatest
+import kotlinx.coroutines.flow.flatMapMerge
+import kotlinx.coroutines.flow.flowOf
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.onEach
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import javax.inject.Inject
 
 @QuranPageScope
-internal class TranslationPresenter @Inject internal constructor(translationModel: TranslationModel,
-                     private val quranSettings: QuranSettings,
-                     translationsAdapter: TranslationsDBAdapter,
-                     translationUtil: TranslationUtil,
-                     private val quranInfo: QuranInfo,
-                     private val pages: IntArray) :
-    BaseTranslationPresenter<TranslationPresenter.TranslationScreen>(
-        translationModel, translationsAdapter, translationUtil, quranInfo) {
+internal class TranslationPresenter @Inject internal constructor(
+  translationModel: TranslationModel,
+  private val quranSettings: QuranSettings,
+  translationsAdapter: TranslationsDBAdapter,
+  translationUtil: TranslationUtil,
+  private val quranInfo: QuranInfo,
+  private val pages: IntArray
+) :
+  BaseTranslationPresenter<TranslationPresenter.TranslationScreen>(
+    translationModel, translationsAdapter, translationUtil, quranInfo
+  ) {
 
-  fun refresh() {
-    disposable?.dispose()
+  private val scope = MainScope()
 
-    disposable = Observable.fromArray(*pages.toTypedArray())
-        .flatMap { page ->
-          getVerses(quranSettings.wantArabicInTranslationView(),
-              getTranslations(quranSettings), quranInfo.getVerseRangeForPage(page))
-              .toObservable()
-        }
-        .observeOn(AndroidSchedulers.mainThread())
-        .subscribeWith(object : DisposableObserver<ResultHolder>() {
-          override fun onNext(result: ResultHolder) {
-            val screen = translationScreen
-            if (screen != null && result.ayahInformation.isNotEmpty()) {
-              screen.setVerses(
-                  getPage(result.ayahInformation), result.translations,
-                  result.ayahInformation)
-              screen.updateScrollPosition()
-            }
-          }
-
-          override fun onError(e: Throwable) {}
+  fun legacyRefresh() {
+    scope.launch {
+      refresh()
+    }
+  }
 
-          override fun onComplete() {}
-        })
+  suspend fun refresh() {
+    pages
+      .map {
+        withContext(Dispatchers.IO) {
+          getVerses(
+            quranSettings.wantArabicInTranslationView(),
+            getTranslations(quranSettings), quranInfo.getVerseRangeForPage(it)
+          )
+        }
+      }
+      .onEach { result ->
+        val screen = translationScreen
+        if (screen != null && result.ayahInformation.isNotEmpty()) {
+          screen.setVerses(
+            getPage(result.ayahInformation), result.translations,
+            result.ayahInformation
+          )
+          screen.updateScrollPosition()
+        }
+      }
   }
 
   private fun getPage(result: List<QuranAyahInfo>): Int {
@@ -60,9 +78,12 @@ internal class TranslationPresenter @Inject internal constructor(translationMode
   }
 
   interface TranslationScreen {
-    fun setVerses(page: Int,
-                  translations: Array<LocalTranslation>,
-                  verses: List<@JvmSuppressWildcards QuranAyahInfo>)
+    fun setVerses(
+      page: Int,
+      translations: Array<LocalTranslation>,
+      verses: List<@JvmSuppressWildcards QuranAyahInfo>
+    )
+
     fun updateScrollPosition()
   }
 }