Add setting for subtitle outline size (#375)

Adds a settings allowing for adjusting the thickness of unstyled
subtitle outlines, if outline is enabled.

This is applied for both ExoPlayer & MPV

Closes #179

![outline
Large](https://github.com/user-attachments/assets/dfef74a5-a4d4-49db-a8d2-231e46ab151e)

Dev note: the ExoPlayer implementation is bad code, don't write code
like this. It works though

app/src/main/java/com/github/damontecres/wholphin/preferences/AppPreferencesSerializer.kt

@@ -170,4 +170,5 @@ fun SubtitlePreferences.Builder.resetSubtitles() {
     backgroundOpacity = SubtitleSettings.BackgroundOpacity.defaultValue.toInt()
     backgroundStyle = SubtitleSettings.BackgroundStylePref.defaultValue
     margin = SubtitleSettings.Margin.defaultValue.toInt()
+    edgeThickness = SubtitleSettings.EdgeThickness.defaultValue.toInt()
 }

app/src/main/java/com/github/damontecres/wholphin/services/AppUpgradeHandler.kt

@@ -163,4 +163,14 @@ suspend fun upgradeApp(
             }
         }
     }
+
+    if (previous.isEqualOrBefore(Version.fromString("0.3.5-0-g0"))) {
+        appPreferences.updateData {
+            it.updateSubtitlePreferences {
+                if (edgeThickness < 1) {
+                    edgeThickness = SubtitleSettings.EdgeThickness.defaultValue.toInt()
+                }
+            }
+        }
+    }
 }

app/src/main/java/com/github/damontecres/wholphin/ui/playback/PlaybackPage.kt

@@ -73,12 +73,14 @@ import com.github.damontecres.wholphin.ui.components.ErrorMessage
 import com.github.damontecres.wholphin.ui.components.LoadingPage
 import com.github.damontecres.wholphin.ui.nav.Destination
 import com.github.damontecres.wholphin.ui.preferences.subtitle.SubtitleSettings.applyToMpv
+import com.github.damontecres.wholphin.ui.preferences.subtitle.SubtitleSettings.calculateEdgeSize
 import com.github.damontecres.wholphin.ui.preferences.subtitle.SubtitleSettings.toSubtitleStyle
 import com.github.damontecres.wholphin.ui.seasonEpisode
 import com.github.damontecres.wholphin.ui.skipStringRes
 import com.github.damontecres.wholphin.ui.tryRequestFocus
 import com.github.damontecres.wholphin.util.ExceptionHandler
 import com.github.damontecres.wholphin.util.LoadingState
+import com.github.damontecres.wholphin.util.Media3SubtitleOverride
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
@@ -329,6 +331,10 @@ fun PlaybackPage(
                             },
                             update = {
                                 it.setCues(cues)
+                                Media3SubtitleOverride(
+                                    preferences.appPreferences.interfacePreferences.subtitlesPreferences
+                                        .calculateEdgeSize(density),
+                                ).apply(it)
                             },
                             onReset = {
                                 it.setCues(null)

app/src/main/java/com/github/damontecres/wholphin/ui/preferences/subtitle/SubtitleSettings.kt

@@ -140,6 +140,23 @@ object SubtitleSettings {
             },
         )
 
+    val EdgeThickness =
+        AppSliderPreference<AppPreferences>(
+            title = R.string.edge_size,
+            defaultValue = 4,
+            min = 1,
+            max = 32,
+            interval = 1,
+            getter = {
+                it.interfacePreferences.subtitlesPreferences.edgeThickness
+                    .toLong()
+            },
+            setter = { prefs, value ->
+                prefs.updateSubtitlePreferences { edgeThickness = value.toInt() }
+            },
+            summarizer = { value -> value?.let { "${it / 2.0}" } },
+        )
+
     val BackgroundColor =
         AppChoicePreference<AppPreferences, Color>(
             title = R.string.background_color,
@@ -230,6 +247,7 @@ object SubtitleSettings {
                     listOf(
                         EdgeStylePref,
                         EdgeColor,
+                        EdgeThickness,
                     ),
             ),
             PreferenceGroup(
@@ -278,6 +296,8 @@ object SubtitleSettings {
         )
     }
 
+    fun SubtitlePreferences.calculateEdgeSize(density: Density): Float = with(density) { (edgeThickness / 2f).dp.toPx() }
+
     fun SubtitlePreferences.applyToMpv(
         configuration: Configuration,
         density: Density,
@@ -316,6 +336,8 @@ object SubtitleSettings {
                 MPVLib.setPropertyDouble("sub-outline-size", 0.0)
             }
         }
+        val outlineSizePx = calculateEdgeSize(density) * .8
+        MPVLib.setPropertyDouble("sub-outline-size", outlineSizePx)
 
 //        if (fontBold) {
 //            MPVLib.setPropertyString("sub-font", "Roboto Bold")

app/src/main/java/com/github/damontecres/wholphin/ui/preferences/subtitle/SubtitleStylePage.kt

@@ -20,6 +20,7 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.layout.ContentScale
+import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.viewinterop.AndroidView
@@ -32,7 +33,9 @@ import com.github.damontecres.wholphin.preferences.AppPreferences
 import com.github.damontecres.wholphin.ui.preferences.PreferenceScreenOption
 import com.github.damontecres.wholphin.ui.preferences.PreferencesContent
 import com.github.damontecres.wholphin.ui.preferences.PreferencesViewModel
+import com.github.damontecres.wholphin.ui.preferences.subtitle.SubtitleSettings.calculateEdgeSize
 import com.github.damontecres.wholphin.ui.preferences.subtitle.SubtitleSettings.toSubtitleStyle
+import com.github.damontecres.wholphin.util.Media3SubtitleOverride
 
 @OptIn(UnstableApi::class)
 @Composable
@@ -41,6 +44,7 @@ fun SubtitleStylePage(
     modifier: Modifier = Modifier,
     viewModel: PreferencesViewModel = hiltViewModel(),
 ) {
+    val density = LocalDensity.current
     var preferences by remember { mutableStateOf(initialPreferences) }
     LaunchedEffect(Unit) {
         viewModel.preferenceDataStore.data.collect {
@@ -95,6 +99,7 @@ fun SubtitleStylePage(
                                         Cue.Builder().setText(text).build(),
                                     ),
                                 )
+                                Media3SubtitleOverride(prefs.calculateEdgeSize(density)).apply(it)
                             },
                             modifier =
                                 Modifier

app/src/main/java/com/github/damontecres/wholphin/util/Media3SubtitleOverride.kt

@@ -0,0 +1,56 @@
+package com.github.damontecres.wholphin.util
+
+import androidx.media3.ui.SubtitleView
+import timber.log.Timber
+import java.lang.reflect.Field
+
+/**
+ * Utility class to override private fields in media3's [SubtitleView]
+ */
+class Media3SubtitleOverride(
+    val outlineThicknessPx: Float,
+) {
+    companion object {
+        private lateinit var outputField: Field
+        private lateinit var classCanvasSubtitleOutput: Class<*>
+        private lateinit var paintersField: Field
+        private lateinit var classSubtitlePainter: Class<*>
+        private lateinit var outlineWidthField: Field
+
+        var initialized: Boolean
+            private set
+
+        init {
+            try {
+                // This is bad times
+                outputField = SubtitleView::class.java.getDeclaredField("output")
+                classCanvasSubtitleOutput = Class.forName("androidx.media3.ui.CanvasSubtitleOutput")
+                paintersField = classCanvasSubtitleOutput.getDeclaredField("painters")
+                classSubtitlePainter = Class.forName("androidx.media3.ui.SubtitlePainter")
+                outlineWidthField = classSubtitlePainter.getDeclaredField("outlineWidth")
+                outputField.isAccessible = true
+                outlineWidthField.isAccessible = true
+                paintersField.isAccessible = true
+                initialized = true
+            } catch (ex: Exception) {
+                Timber.w(ex, "Error initializing")
+                initialized = false
+            }
+        }
+    }
+
+    fun apply(subtitleView: SubtitleView) {
+        try {
+            if (initialized) {
+                // Basically hijack the field that controls the subtitle outline size
+                val canvasSubtitleOutput = outputField.get(subtitleView)
+                val painters = paintersField.get(canvasSubtitleOutput) as List<*>
+                painters.forEach { painter ->
+                    outlineWidthField.set(painter, outlineThicknessPx)
+                }
+            }
+        } catch (ex: Exception) {
+            Timber.w(ex, "Failed to apply")
+        }
+    }
+}

app/src/main/proto/WholphinDataStore.proto

@@ -121,6 +121,7 @@ message SubtitlePreferences{
   bool font_bold = 9;
   bool font_italic = 10;
   int32 margin = 11;
+  int32 edge_thickness = 12;
 }
 
 message InterfacePreferences {

app/src/main/res/values/strings.xml

@@ -349,6 +349,7 @@
     <string name="image_type">Image type</string>
     <string name="cast_and_crew"><![CDATA[Cast & Crew]]></string>
     <string name="guest_stars">Guest stars</string>
+    <string name="edge_size">Edge size</string>
 
 
     <string-array name="theme_song_volume">

app/src/test/java/com/github/damontecres/wholphin/test/TestMedia3SubtitleOverride.kt

@@ -0,0 +1,14 @@
+package com.github.damontecres.wholphin.test
+
+import com.github.damontecres.wholphin.util.Media3SubtitleOverride
+import org.junit.Assert
+import org.junit.Test
+
+class TestMedia3SubtitleOverride {
+    @Test
+    fun test() {
+        // This tests whether the class and field names exist
+        Media3SubtitleOverride(2f)
+        Assert.assertTrue(Media3SubtitleOverride.Companion.initialized)
+    }
+}