Adds option to dim the screensaver (#1834)

## Description
Adds a new sceensaver setting to add dimming. A larger value is darker

This works with or without the in-app screensaver. If dimming is
enabled, the screen be will be dimmed after inactivity. If both dimming
and the in-app screensaver are enabled, the screensaver will show dimmed
after inactivity.

### Related issues
Closes #1179

### Testing
Emulator

## Screenshots
N/A, it's just darker

## AI or LLM usage
None

app/src/main/java/com/github/damontecres/wholphin/MainContent.kt

@@ -17,6 +17,7 @@ import androidx.compose.runtime.rememberUpdatedState
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.RectangleShape
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.Lifecycle
@@ -136,12 +137,26 @@ fun MainContent(
             val screenSaverState by screensaverService.state.collectAsState()
             if (screenSaverState.enabled || screenSaverState.enabledTemp) {
                 AnimatedVisibility(
-                    screenSaverState.show,
+                    visible = screenSaverState.show,
-                    Modifier.fillMaxSize(),
+                    enter = ScreensaverService.enterAnimation,
+                    exit = ScreensaverService.exitAnimation,
+                    modifier = Modifier.fillMaxSize(),
                 ) {
                     AppScreensaver(userPreferences.appPreferences, Modifier.fillMaxSize())
                 }
             }
+            AnimatedVisibility(
+                visible = screenSaverState.showDim || (screenSaverState.dimEnabled && screenSaverState.show),
+                enter = ScreensaverService.enterAnimation,
+                exit = ScreensaverService.exitAnimation,
+                modifier = Modifier.fillMaxSize(),
+            ) {
+                val alpha =
+                    userPreferences.appPreferences.interfacePreferences.screensaverPreference.dimPercent / 100f
+                Box(
+                    Modifier.background(Color.Black.copy(alpha = alpha)),
+                )
+            }
         }
     }
 }

app/src/main/java/com/github/damontecres/wholphin/WholphinDreamService.kt

@@ -9,6 +9,7 @@ import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.alpha
 import androidx.compose.ui.platform.ComposeView
 import androidx.datastore.core.DataStore
 import androidx.lifecycle.Lifecycle
@@ -94,6 +95,14 @@ class WholphinDreamService :
                             preferencesDataStore.data.collectLatest { prefs = it }
                         }
                         prefs?.let { prefs ->
+                            val alpha =
+                                prefs.interfacePreferences.screensaverPreference.run {
+                                    if (dimEnabled) {
+                                        dimPercent / 100f
+                                    } else {
+                                        1f
+                                    }
+                                }
                             CoilConfig(
                                 prefs = prefs,
                                 okHttpClient = okHttpClient,
@@ -109,7 +118,10 @@ class WholphinDreamService :
                                         showClock = screensaverPrefs.showClock,
                                         duration = screensaverPrefs.duration.milliseconds,
                                         animate = screensaverPrefs.animate,
-                                        modifier = Modifier.fillMaxSize(),
+                                        modifier =
+                                            Modifier
+                                                .fillMaxSize()
+                                                .alpha(alpha = alpha),
                                     )
                                 }
                             }

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

@@ -1338,6 +1338,14 @@ val screensaverPreferences =
                     ScreensaverPreference.Start,
                 ),
         ),
+        PreferenceGroup(
+            title = R.string.dim_screen,
+            preferences =
+                listOf(
+                    ScreensaverPreference.DimToggle,
+                    ScreensaverPreference.DimPercentage,
+                ),
+        ),
     )
 
 data class AppSwitchPreference<Pref>(

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

@@ -176,6 +176,37 @@ object ScreensaverPreference {
             },
         )
 
+    val DimToggle =
+        AppSwitchPreference<AppPreferences>(
+            title = R.string.dim_after_delay,
+            defaultValue = AppPreference.ShowClock.defaultValue,
+            getter = { it.interfacePreferences.screensaverPreference.dimEnabled },
+            setter = { prefs, value ->
+                prefs.updateScreensaverPreferences { dimEnabled = value }
+            },
+            summaryOn = R.string.yes,
+            summaryOff = R.string.no,
+        )
+
+    val DimPercentage =
+        AppSliderPreference<AppPreferences>(
+            title = R.string.dim_percentage,
+            defaultValue = 75,
+            min = 0,
+            max = 95,
+            interval = 5,
+            getter = {
+                it.interfacePreferences.screensaverPreference.dimPercent
+                    .toLong()
+            },
+            setter = { prefs, value ->
+                prefs.updateScreensaverPreferences { dimPercent = value.toInt() }
+            },
+            summarizer = { value ->
+                value?.let { "$value%" }
+            },
+        )
+
     val Start =
         AppClickablePreference<AppPreferences>(
             title = R.string.start_screensaver,

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

@@ -418,5 +418,13 @@ class AppUpgradeHandler
                     }
                 }
             }
+
+            if (previous.isEqualOrBefore(Version.fromString("1.0.6-0-g0"))) {
+                appPreferences.updateData {
+                    it.updateScreensaverPreferences {
+                        dimPercent = ScreensaverPreference.DimPercentage.defaultValue.toInt()
+                    }
+                }
+            }
         }
     }

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

@@ -1,6 +1,9 @@
 package com.github.damontecres.wholphin.services
 
 import android.content.Context
+import androidx.compose.animation.core.tween
+import androidx.compose.animation.fadeIn
+import androidx.compose.animation.fadeOut
 import coil3.imageLoader
 import coil3.request.ImageRequest
 import com.github.damontecres.wholphin.services.hilt.DefaultCoroutineScope
@@ -57,6 +60,7 @@ class ScreensaverService
         val keepScreenOn = MutableStateFlow(false)
 
         private var waitJob: Job? = null
+        private var dimJob: Job? = null
 
         init {
             userPreferencesService.flow
@@ -65,7 +69,14 @@ class ScreensaverService
                         val enabled =
                             prefs.appPreferences.interfacePreferences.screensaverPreference.enabled
                         keepScreenOnInternal(enabled)
-                        ScreensaverState(enabled, false, false, false)
+                        ScreensaverState(
+                            enabled = enabled,
+                            enabledTemp = false,
+                            active = false,
+                            paused = false,
+                            dimEnabled = prefs.appPreferences.interfacePreferences.screensaverPreference.dimEnabled,
+                            dimActive = false,
+                        )
                     }
                 }.launchIn(scope)
         }
@@ -74,12 +85,16 @@ class ScreensaverService
          * Reset the timer before showing the in-app screensaver
          */
         fun pulse() {
+            Timber.v("state=%s", _state.value)
             waitJob?.cancel()
             if (_state.value.enabled) {
 //                Timber.v("pulse")
                 _state.update {
                     if (!it.active) {
-                        it.copy(active = false)
+                        it.copy(
+                            active = false,
+                            dimActive = false,
+                        )
                     } else {
                         it
                     }
@@ -94,7 +109,30 @@ class ScreensaverService
                                     .appPreferences.interfacePreferences.screensaverPreference.startDelay.milliseconds
                             delay(startDelay)
                             _state.update {
-                                it.copy(active = true)
+                                it.copy(
+                                    active = true,
+                                    dimActive = it.dimEnabled,
+                                )
+                            }
+                        }
+                }
+            }
+            dimJob?.cancel()
+            if (_state.value.dimEnabled) {
+                _state.update {
+                    it.copy(dimActive = false)
+                }
+                if (!_state.value.paused) {
+                    dimJob =
+                        scope.launch(ExceptionHandler()) {
+                            val startDelay =
+                                userPreferencesService
+                                    .getCurrent()
+                                    .appPreferences.interfacePreferences.screensaverPreference.startDelay.milliseconds
+                            delay(startDelay)
+                            Timber.v("state dim=%s", _state.value)
+                            _state.update {
+                                it.copy(dimActive = !_state.value.paused)
                             }
                         }
                 }
@@ -109,6 +147,7 @@ class ScreensaverService
                 it.copy(
                     enabledTemp = true,
                     active = true,
+                    dimActive = true,
                 )
             }
         }
@@ -121,9 +160,13 @@ class ScreensaverService
                 it.copy(
                     enabledTemp = false,
                     active = false,
+                    dimActive = false,
                 )
             }
-            if (cancelJob) waitJob?.cancel()
+            if (cancelJob) {
+                waitJob?.cancel()
+                dimJob?.cancel()
+            }
         }
 
         /**
@@ -131,12 +174,16 @@ class ScreensaverService
          */
         fun keepScreenOn(keep: Boolean) {
             scope.launchDefault {
-                val screensaverEnabled = _state.value.enabled
+                val screensaverEnabled = _state.value.run { enabled || dimEnabled }
                 Timber.d("Keep screen on: %s, screensaverEnabled=%s", keep, screensaverEnabled)
                 if (screensaverEnabled) {
                     // Page is requesting to keep screen on, so we don't wait to show the screensaver
                     _state.update {
-                        it.copy(active = false, paused = keep)
+                        it.copy(
+                            active = false,
+                            dimActive = false,
+                            paused = keep,
+                        )
                     }
                     if (!keep) {
                         pulse()
@@ -245,6 +292,11 @@ class ScreensaverService
                 )
             return ApiRequestPager(api, request, GetItemsRequestHandler, scope).init()
         }
+
+        companion object {
+            val enterAnimation = fadeIn(animationSpec = tween(durationMillis = 1000))
+            val exitAnimation = fadeOut(animationSpec = tween(durationMillis = 500))
+        }
     }
 
 data class ScreensaverState(
@@ -252,6 +304,10 @@ data class ScreensaverState(
     val enabledTemp: Boolean,
     val active: Boolean,
     val paused: Boolean,
+    val dimEnabled: Boolean = false,
+    val dimActive: Boolean = false,
 ) {
     val show get() = (enabled || enabledTemp) && active && !paused
+
+    val showDim get() = dimEnabled && dimActive && !paused
 }

app/src/main/proto/WholphinDataStore.proto

@@ -174,6 +174,8 @@ message ScreensaverPreferences{
   bool enabled = 5;
   repeated string item_types = 6;
   bool show_clock = 7;
+  bool dim_enabled = 8;
+  int32 dim_percent = 9;
 }
 
 message SearchPreferences {

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

@@ -910,4 +910,7 @@
     <string name="audio_books">Audio books</string>
     <string name="server_version_not_supported">Server version not supported</string>
     <string name="appears_on">Appears on</string>
+    <string name="dim_after_delay">Dim screen after delay</string>
+    <string name="dim_percentage">Dim percentage</string>
+    <string name="dim_screen">Dim screen</string>
 </resources>