feat: Preserve source and subtitle selection between episodes

app/src/main/java/com/lagradost/cloudstream3/ui/player/EpisodePlaybackSelection.kt

@@ -0,0 +1,88 @@
+package com.lagradost.cloudstream3.ui.player
+
+import com.lagradost.cloudstream3.utils.ExtractorLinkType
+
+internal data class EpisodeSourceSelection(
+    val source: String?,
+    val name: String,
+    val quality: Int?,
+    val type: ExtractorLinkType?,
+)
+
+internal sealed interface EpisodeSubtitleSelection {
+    data class Selected(
+        val originalName: String,
+        val nameSuffix: String,
+    ) : EpisodeSubtitleSelection
+
+    data object Disabled : EpisodeSubtitleSelection
+}
+
+internal data class EpisodeSubtitleResolution(
+    val subtitle: SubtitleData?,
+    val selectionMatched: Boolean,
+    val subtitlesDisabled: Boolean,
+)
+
+internal fun VideoLink.toEpisodeSourceSelection(): EpisodeSourceSelection? {
+    val link = first
+    if (link != null) {
+        return EpisodeSourceSelection(link.source, link.name, link.quality, link.type)
+    }
+
+    val uri = second ?: return null
+    return EpisodeSourceSelection(null, uri.name, null, null)
+}
+
+internal fun findEpisodeSource(
+    links: List<VideoLink>,
+    selection: EpisodeSourceSelection?,
+): VideoLink? {
+    return selection?.let { remembered ->
+        links.firstOrNull { it.toEpisodeSourceSelection() == remembered }
+    }
+}
+
+internal fun createEpisodeSubtitleSelection(
+    subtitle: SubtitleData?,
+    subtitlesDisabled: Boolean,
+): EpisodeSubtitleSelection? {
+    return when {
+        subtitle != null -> EpisodeSubtitleSelection.Selected(
+            subtitle.originalName,
+            subtitle.nameSuffix,
+        )
+
+        subtitlesDisabled -> EpisodeSubtitleSelection.Disabled
+        else -> null
+    }
+}
+
+internal fun findEpisodeSubtitle(
+    subtitles: Set<SubtitleData>,
+    selection: EpisodeSubtitleSelection?,
+): SubtitleData? {
+    val remembered = selection as? EpisodeSubtitleSelection.Selected ?: return null
+    return subtitles.firstOrNull {
+        it.originalName == remembered.originalName &&
+                it.nameSuffix == remembered.nameSuffix
+    }
+}
+
+internal fun resolveEpisodeSubtitle(
+    subtitles: Set<SubtitleData>,
+    selection: EpisodeSubtitleSelection?,
+    fallback: () -> SubtitleData?,
+): EpisodeSubtitleResolution {
+    val rememberedSubtitle = findEpisodeSubtitle(subtitles, selection)
+    val subtitlesDisabled = selection == EpisodeSubtitleSelection.Disabled
+    return EpisodeSubtitleResolution(
+        subtitle = when {
+            subtitlesDisabled -> null
+            rememberedSubtitle != null -> rememberedSubtitle
+            else -> fallback()
+        },
+        selectionMatched = rememberedSubtitle != null,
+        subtitlesDisabled = subtitlesDisabled,
+    )
+}

app/src/main/java/com/lagradost/cloudstream3/ui/player/GeneratorPlayer.kt

@@ -47,7 +47,6 @@ import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import com.lagradost.cloudstream3.APIHolder.getApiFromNameNull
 import com.lagradost.cloudstream3.CloudStreamApp
-import com.lagradost.cloudstream3.CloudStreamApp.Companion.setKey
 import com.lagradost.cloudstream3.CommonActivity.showToast
 import com.lagradost.cloudstream3.LoadResponse
 import com.lagradost.cloudstream3.LoadResponse.Companion.getAniListId
@@ -96,7 +95,6 @@ import com.lagradost.cloudstream3.ui.settings.Globals.EMULATOR
 import com.lagradost.cloudstream3.ui.settings.Globals.PHONE
 import com.lagradost.cloudstream3.ui.settings.Globals.TV
 import com.lagradost.cloudstream3.ui.settings.Globals.isLayout
-import com.lagradost.cloudstream3.ui.subtitles.SUBTITLE_AUTO_SELECT_KEY
 import com.lagradost.cloudstream3.ui.subtitles.SubtitlesFragment
 import com.lagradost.cloudstream3.ui.subtitles.SubtitlesFragment.Companion.getAutoSelectLanguageTagIETF
 import com.lagradost.cloudstream3.utils.AppContextUtils.getShortSeasonText
@@ -177,13 +175,32 @@ class GeneratorPlayer : FullScreenPlayer() {
 
     private var currentSelectedLink: Pair<ExtractorLink?, ExtractorUri?>? = null
     private var currentSelectedSubtitles: SubtitleData? = null
+    private var nextEpisodeSelection: EpisodePlaybackSelection? = null
     private val currentMeta: Any? get() = viewModel.state.generatorState?.meta
     private val nextMeta: Any? get() = viewModel.state.generatorState?.nextMeta
 
     private var isPlayerActive: AtomicBoolean = AtomicBoolean(false)
     private var isNextEpisode: Boolean = false // this is used to reset the watch time
 
     private var preferredAutoSelectSubtitles: String? = null // null means do nothing, "" means none
+    private var subtitlesDisabledByUser = false
+
+    private data class EpisodePlaybackSelection(
+        val source: EpisodeSourceSelection?,
+        val subtitle: EpisodeSubtitleSelection?,
+    )
+
+    private fun rememberEpisodePlaybackSelection() {
+        val subtitle = player.getCurrentPreferredSubtitle() ?: currentSelectedSubtitles
+        nextEpisodeSelection = EpisodePlaybackSelection(
+            source = currentSelectedLink?.toEpisodeSourceSelection(),
+            subtitle = createEpisodeSubtitleSelection(
+                subtitle,
+                subtitlesDisabled = subtitlesDisabledByUser,
+            ),
+        )
+    }
+
     private val allMeta: List<ResultEpisode>?
         get() = viewModel.state.generatorState?.allMeta?.filterIsInstance<ResultEpisode>()
             ?.map { episode ->
@@ -194,19 +211,12 @@ class GeneratorPlayer : FullScreenPlayer() {
             }
 
     private fun setSubtitles(subtitle: SubtitleData?, userInitiated: Boolean): Boolean {
-        // If subtitle is changed and user initiated -> Save the language
-        if (subtitle != currentSelectedSubtitles && userInitiated) {
-            val subtitleLanguageTagIETF = if (subtitle == null) {
-                "" // -> No Subtitles
-            } else {
-                subtitle.getIETF_tag()
-            }
-
-            if (subtitleLanguageTagIETF != null) {
-                Log.i(TAG, "Set SUBTITLE_AUTO_SELECT_KEY to '$subtitleLanguageTagIETF'")
-                setKey(SUBTITLE_AUTO_SELECT_KEY, subtitleLanguageTagIETF)
-                preferredAutoSelectSubtitles = subtitleLanguageTagIETF
-            }
+        if (userInitiated) {
+            nextEpisodeSelection = null
+            subtitlesDisabledByUser = subtitle == null
+        }
+        if (subtitle != null) {
+            subtitlesDisabledByUser = false
         }
 
         currentSelectedSubtitles = subtitle
@@ -523,6 +533,22 @@ class GeneratorPlayer : FullScreenPlayer() {
         context?.let { ctx ->
             val (url, uri) = link
             val subtitles = viewModel.state.subtitles
+            val subtitleSelection = nextEpisodeSelection?.subtitle
+            val subtitleResolution = resolveEpisodeSubtitle(subtitles, subtitleSelection) {
+                getAutoSelectSubtitle(subtitles, settings = true, downloads = true)
+            }
+            val preferredSubtitle =
+                if (sameEpisode) currentSelectedSubtitles else subtitleResolution.subtitle
+            if (!sameEpisode) {
+                subtitlesDisabledByUser = subtitleResolution.subtitlesDisabled
+            }
+            currentSelectedSubtitles = preferredSubtitle
+            if (!sameEpisode &&
+                (subtitleSelection !is EpisodeSubtitleSelection.Selected ||
+                        subtitleResolution.selectionMatched)
+            ) {
+                nextEpisodeSelection = null
+            }
             player.loadPlayer(
                 ctx,
                 sameEpisode,
@@ -532,9 +558,7 @@ class GeneratorPlayer : FullScreenPlayer() {
                     if (isNextEpisode) 0L else getPos()
                 },
                 subtitles,
-                (if (sameEpisode) currentSelectedSubtitles else null) ?: getAutoSelectSubtitle(
-                    subtitles, settings = true, downloads = true
-                ),
+                preferredSubtitle,
                 preview = true
             )
         }
@@ -1574,7 +1598,19 @@ class GeneratorPlayer : FullScreenPlayer() {
         if (!isPlayerActive.compareAndSet(false, true)) {
             return
         }
-        loadLink(links.first(), false)
+
+        val preferredSource = nextEpisodeSelection?.source
+        val preferredLink = findEpisodeSource(links, preferredSource)
+        if (preferredSource != null &&
+            preferredLink == null &&
+            viewModel.state.loading is Resource.Loading
+        ) {
+            isPlayerActive.set(false)
+            return
+        }
+
+        nextEpisodeSelection = nextEpisodeSelection?.copy(source = null)
+        loadLink(preferredLink ?: links.first(), false)
         showPlayerMetadata()
     }
 
@@ -1628,6 +1664,7 @@ class GeneratorPlayer : FullScreenPlayer() {
     override fun nextEpisode() {
         if (viewModel.hasNextEpisode() == true) {
             isNextEpisode = true
+            rememberEpisodePlaybackSelection()
             releasePlayer()
             viewModel.loadLinksNext()
         }
@@ -1636,6 +1673,7 @@ class GeneratorPlayer : FullScreenPlayer() {
     override fun prevEpisode() {
         if (viewModel.hasPrevEpisode() == true) {
             isNextEpisode = true
+            rememberEpisodePlaybackSelection()
             releasePlayer()
             viewModel.loadLinksPrev()
         }
@@ -1806,10 +1844,40 @@ class GeneratorPlayer : FullScreenPlayer() {
         player.handleEvent(CSPlayerEvent.Play)
     }
 
+    private fun autoSelectFromPreviousEpisode(): Boolean {
+        if (!isPlayerActive.get()) return false
+        val selection = nextEpisodeSelection ?: return false
+        if (selection.subtitle == EpisodeSubtitleSelection.Disabled) {
+            nextEpisodeSelection = null
+            return true
+        }
+        val subtitle = findEpisodeSubtitle(
+            viewModel.state.subtitles,
+            selection.subtitle,
+        ) ?: run {
+            if (selection.subtitle == null) {
+                nextEpisodeSelection = null
+            }
+            return false
+        }
+        nextEpisodeSelection = null
+        context?.let { ctx ->
+            if (setSubtitles(subtitle, false)) {
+                player.saveData()
+                player.reloadPlayer(ctx)
+                player.handleEvent(CSPlayerEvent.Play)
+            }
+        }
+        return true
+    }
+
     private fun autoSelectSubtitles() {
         //Log.i(TAG, "autoSelectSubtitles")
         safe {
-            if (!autoSelectFromSettings()) {
+            if (!subtitlesDisabledByUser &&
+                !autoSelectFromPreviousEpisode() &&
+                !autoSelectFromSettings()
+            ) {
                 autoSelectFromDownloads()
             }
         }
@@ -2095,6 +2163,7 @@ class GeneratorPlayer : FullScreenPlayer() {
                     { episodeClick ->
                         if (episodeClick.action == ACTION_CLICK_DEFAULT) {
                             isNextEpisode = false
+                            nextEpisodeSelection = null
                             releasePlayer()
                             playerEpisodeOverlay.isGone = true
                             episodeClick.position?.let { viewModel.loadThisEpisode(it) }