new: add playback speed control

data/playback/src/commonMain/kotlin/fr/ajaury/gwenedeg/player/data/PlaybackRepositoryImpl.kt

@@ -136,6 +136,10 @@ internal class PlaybackRepositoryImpl(
         audioPlayer.seekTo(position)
     }
 
+    override fun setSpeed(speed: Float) {
+        audioPlayer.setSpeed(speed)
+    }
+
     override fun seekToSentence(sentenceIndex: Int) {
         val matchingSubtitleLine = subtitle.value.lines.getOrNull(sentenceIndex) ?: return
         audioPlayer.seekTo(matchingSubtitleLine.startTime)

data/playback/src/commonMain/kotlin/fr/ajaury/gwenedeg/player/domain/PlaybackRepository.kt

@@ -25,6 +25,8 @@ interface PlaybackRepository {
 
     fun seekTo(position: Duration)
 
+    fun setSpeed(speed: Float)
+
     fun seekToSentence(sentenceIndex: Int)
 
     fun goToPreviousSentence()

data/preferences/src/commonMain/kotlin/fr/ajaury/gwenedeg/preferences/data/PreferencesRepositoryImpl.kt

@@ -1,6 +1,7 @@
 package fr.ajaury.gwenedeg.preferences.data
 
 import fr.ajaury.gwenedeg.preferences.domain.PreferencesRepository
+import fr.ajaury.gwenedeg.preferences.model.PlaybackPreferences
 import fr.ajaury.gwenedeg.preferences.model.SubtitlePreferences
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
@@ -8,14 +9,21 @@ import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.flow.update
 
 internal class PreferencesRepositoryImpl : PreferencesRepository {
-    private val state = MutableStateFlow(SubtitlePreferences())
-    override val subtitlePreferences: StateFlow<SubtitlePreferences> = state.asStateFlow()
+    private val subtitleState = MutableStateFlow(SubtitlePreferences())
+    override val subtitlePreferences: StateFlow<SubtitlePreferences> = subtitleState.asStateFlow()
+
+    private val playbackState = MutableStateFlow(PlaybackPreferences())
+    override val playbackPreferences: StateFlow<PlaybackPreferences> = playbackState.asStateFlow()
 
     override fun setShowTranscription(enabled: Boolean) {
-        state.update { it.copy(showTranscription = enabled) }
+        subtitleState.update { it.copy(showTranscription = enabled) }
     }
 
     override fun setShowTranslation(enabled: Boolean) {
-        state.update { it.copy(showTranslation = enabled) }
+        subtitleState.update { it.copy(showTranslation = enabled) }
+    }
+
+    override fun setPlaybackSpeed(speed: Float) {
+        playbackState.update { it.copy(speed = speed) }
     }
 }

data/preferences/src/commonMain/kotlin/fr/ajaury/gwenedeg/preferences/domain/PreferencesRepository.kt

@@ -1,12 +1,17 @@
 package fr.ajaury.gwenedeg.preferences.domain
 
+import fr.ajaury.gwenedeg.preferences.model.PlaybackPreferences
 import fr.ajaury.gwenedeg.preferences.model.SubtitlePreferences
 import kotlinx.coroutines.flow.StateFlow
 
 interface PreferencesRepository {
     val subtitlePreferences: StateFlow<SubtitlePreferences>
 
+    val playbackPreferences: StateFlow<PlaybackPreferences>
+
     fun setShowTranscription(enabled: Boolean)
 
     fun setShowTranslation(enabled: Boolean)
+
+    fun setPlaybackSpeed(speed: Float)
 }

data/preferences/src/commonMain/kotlin/fr/ajaury/gwenedeg/preferences/model/PlaybackPreferences.kt

@@ -0,0 +1,18 @@
+package fr.ajaury.gwenedeg.preferences.model
+
+/**
+ * User preferences controlling audio playback.
+ *
+ * @property speed playback speed multiplier, clamped between [MIN_SPEED] and [MAX_SPEED] in
+ * [SPEED_STEP] increments. [DEFAULT_SPEED] is the normal, unaltered speed.
+ */
+data class PlaybackPreferences(
+    val speed: Float = DEFAULT_SPEED,
+) {
+    companion object {
+        const val DEFAULT_SPEED = 1f
+        const val MIN_SPEED = 0.5f
+        const val MAX_SPEED = 1f
+        const val SPEED_STEP = 0.1f
+    }
+}