new: add previous and next sentence navigation in PlayerControl and PlayerViewModel

shared/src/commonMain/kotlin/fr/ajaury/gwenedeg/player/ui/PlayerControl.kt

@@ -3,14 +3,18 @@ package fr.ajaury.gwenedeg.player.ui
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.size
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Pause
 import androidx.compose.material.icons.filled.PlayArrow
 import androidx.compose.material.icons.filled.Replay
+import androidx.compose.material.icons.filled.SkipNext
+import androidx.compose.material.icons.filled.SkipPrevious
 import androidx.compose.material3.Button
 import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
 import androidx.compose.material3.Slider
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
@@ -20,9 +24,11 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import fr.ajaury.gwenedeg.player.model.PlaybackState
 import fr.ajaury.gwenedeg.player.model.PlaybackTiming
+import fr.ajaury.gwenedeg.theme.GwenedegTheme
 
 @Composable
 fun PlayerControl(
@@ -30,6 +36,8 @@ fun PlayerControl(
     playbackTiming: PlaybackTiming,
     onSeek: (Float) -> Unit = {},
     onMainPlayActionButtonClicked: () -> Unit = {},
+    onPreviousSentenceClicked: () -> Unit = {},
+    onNextSentenceClicked: () -> Unit = {},
 ) {
     Column(
         modifier = Modifier.fillMaxWidth(),
@@ -51,15 +59,40 @@ fun PlayerControl(
             modifier = Modifier.fillMaxWidth(),
         )
 
-        Button(
-            modifier = Modifier.size(60.dp),
-            contentPadding = PaddingValues(0.dp),
-            onClick = onMainPlayActionButtonClicked,
+        Row(
+            verticalAlignment = Alignment.CenterVertically,
+            horizontalArrangement = Arrangement.spacedBy(16.dp),
         ) {
-            Icon(
-                imageVector = playbackState.toActionIcon(),
-                contentDescription = playbackState.toActionContentDescription(),
-            )
+            IconButton(
+                modifier = Modifier.size(60.dp),
+                onClick = onPreviousSentenceClicked,
+            ) {
+                Icon(
+                    imageVector = Icons.Default.SkipPrevious,
+                    contentDescription = "Previous sentence",
+                )
+            }
+
+            Button(
+                modifier = Modifier.size(60.dp),
+                contentPadding = PaddingValues(0.dp),
+                onClick = onMainPlayActionButtonClicked,
+            ) {
+                Icon(
+                    imageVector = playbackState.toActionIcon(),
+                    contentDescription = playbackState.toActionContentDescription(),
+                )
+            }
+
+            IconButton(
+                modifier = Modifier.size(60.dp),
+                onClick = onNextSentenceClicked,
+            ) {
+                Icon(
+                    imageVector = Icons.Default.SkipNext,
+                    contentDescription = "Next sentence",
+                )
+            }
         }
     }
 }
@@ -77,3 +110,14 @@ private fun PlaybackState.toActionContentDescription(): String =
         PlaybackState.ENDED -> "Replay"
         PlaybackState.PAUSED, PlaybackState.IDLE -> "Play"
     }
+
+@Preview
+@Composable
+private fun PlayerControlPreview() {
+    GwenedegTheme {
+        PlayerControl(
+            playbackState = PlaybackState.PLAYING,
+            playbackTiming = PlaybackTiming(positionMs = 1234, durationMs = 5000),
+        )
+    }
+}

shared/src/commonMain/kotlin/fr/ajaury/gwenedeg/player/ui/PlayerScreen.kt

@@ -50,6 +50,8 @@ fun PlayerScreen(
         onMainPlayActionButtonClicked = viewModel::performMainPlayAction,
         onSeekToTimePart = viewModel::seekToTimePart,
         onSeekToSentence = viewModel::seekToSentence,
+        onPreviousSentenceClicked = viewModel::goToPreviousSentence,
+        onNextSentenceClicked = viewModel::goToNextSentence,
         onBackClicked = onBackClicked,
     )
 }
@@ -61,6 +63,8 @@ fun PlayerScreen(
     onMainPlayActionButtonClicked: () -> Unit = {},
     onSeekToTimePart: (progress: Float) -> Unit = {},
     onSeekToSentence: (position: Int) -> Unit = {},
+    onPreviousSentenceClicked: () -> Unit = {},
+    onNextSentenceClicked: () -> Unit = {},
     onBackClicked: () -> Unit = {},
 ) {
     Scaffold(
@@ -106,6 +110,8 @@ fun PlayerScreen(
                 playbackTiming = uiState.playbackTiming,
                 onSeek = onSeekToTimePart,
                 onMainPlayActionButtonClicked = onMainPlayActionButtonClicked,
+                onPreviousSentenceClicked = onPreviousSentenceClicked,
+                onNextSentenceClicked = onNextSentenceClicked,
             )
         }
     }

shared/src/commonMain/kotlin/fr/ajaury/gwenedeg/player/ui/viewmodel/PlayerViewModel.kt

@@ -165,6 +165,33 @@ class PlayerViewModel(
         audioPlayer.seekTo(matchingSubtitleLine.startMs.milliseconds)
     }
 
+    fun goToPreviousSentence() {
+        val lines = subtitle.value.lines
+        val currentIndex = currentSentenceIndex() ?: return
+        val currentLine = lines.getOrNull(currentIndex) ?: return
+        val elapsedInSentence =
+            audioPlayer.currentPosition.inWholeMilliseconds - currentLine.startMs
+        val targetIndex = if (elapsedInSentence < PREVIOUS_SENTENCE_THRESHOLD.inWholeMilliseconds) {
+            (currentIndex - 1)
+        } else {
+            currentIndex
+        }.coerceAtLeast(0)
+
+        seekToSentence(targetIndex)
+    }
+
+    fun goToNextSentence() {
+        val lines = subtitle.value.lines
+        val currentIndex = currentSentenceIndex() ?: return
+        seekToSentence((currentIndex + 1).coerceAtMost(lines.lastIndex))
+    }
+
+    private fun currentSentenceIndex(): Int? =
+        getCurrentSubtitleIndex(
+            subtitle = subtitle.value,
+            progressMs = audioPlayer.currentPosition.inWholeMilliseconds,
+        )
+
     fun stop() {
         audioPlayer.stop()
     }
@@ -177,5 +204,6 @@ class PlayerViewModel(
 
     companion object {
         private val POSITION_POLL_INTERVAL = 50.milliseconds
+        private val PREVIOUS_SENTENCE_THRESHOLD = 4.seconds
     }
 }