Introduce MediaViewerFlickToDismiss and extract to its own file

libraries/mediaviewer/impl/src/main/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerFlickToDismiss.kt

@@ -0,0 +1,85 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.mediaviewer.impl.viewer
+
+import androidx.compose.animation.core.animateFloatAsState
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.BoxScope
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.rememberUpdatedState
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import kotlinx.coroutines.delay
+import me.saket.telephoto.flick.FlickToDismiss
+import me.saket.telephoto.flick.FlickToDismissState
+import me.saket.telephoto.flick.rememberFlickToDismissState
+import kotlin.time.Duration
+
+@Composable
+fun MediaViewerFlickToDismiss(
+    onDismiss: () -> Unit,
+    modifier: Modifier = Modifier,
+    onDragging: () -> Unit = {},
+    content: @Composable BoxScope.() -> Unit,
+) {
+    val flickState = rememberFlickToDismissState(dismissThresholdRatio = 0.1f, rotateOnDrag = false)
+    DismissFlickEffects(
+        flickState = flickState,
+        onDismissing = { animationDuration ->
+            delay(animationDuration / 3)
+            onDismiss()
+        },
+        onDragging = onDragging,
+    )
+    FlickToDismiss(
+        state = flickState,
+        modifier = modifier.background(backgroundColorFor(flickState)),
+        content = content,
+    )
+}
+
+@Composable
+private fun DismissFlickEffects(
+    flickState: FlickToDismissState,
+    onDismissing: suspend (Duration) -> Unit,
+    onDragging: suspend () -> Unit,
+) {
+    val currentOnDismissing by rememberUpdatedState(onDismissing)
+    val currentOnDragging by rememberUpdatedState(onDragging)
+
+    when (val gestureState = flickState.gestureState) {
+        is FlickToDismissState.GestureState.Dismissing -> {
+            LaunchedEffect(Unit) {
+                currentOnDismissing(gestureState.animationDuration)
+            }
+        }
+        is FlickToDismissState.GestureState.Dragging -> {
+            LaunchedEffect(Unit) {
+                currentOnDragging()
+            }
+        }
+        else -> Unit
+    }
+}
+
+@Composable
+private fun backgroundColorFor(flickState: FlickToDismissState): Color {
+    val animatedAlpha by animateFloatAsState(
+        targetValue = when (flickState.gestureState) {
+            is FlickToDismissState.GestureState.Dismissed,
+            is FlickToDismissState.GestureState.Dismissing -> 0f
+            is FlickToDismissState.GestureState.Dragging,
+            is FlickToDismissState.GestureState.Idle,
+            is FlickToDismissState.GestureState.Resetting -> 1f - flickState.offsetFraction
+        },
+        label = "Background alpha",
+    )
+    return Color.Black.copy(alpha = animatedAlpha)
+}

libraries/mediaviewer/impl/src/main/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerView.kt

@@ -11,7 +11,6 @@ package io.element.android.libraries.mediaviewer.impl.viewer
 
 import androidx.activity.compose.BackHandler
 import androidx.compose.animation.AnimatedVisibility
-import androidx.compose.animation.core.animateFloatAsState
 import androidx.compose.animation.fadeIn
 import androidx.compose.animation.fadeOut
 import androidx.compose.foundation.background
@@ -81,13 +80,9 @@ import io.element.android.libraries.mediaviewer.impl.local.PlayableState
 import io.element.android.libraries.mediaviewer.impl.local.rememberLocalMediaViewState
 import io.element.android.libraries.ui.strings.CommonStrings
 import kotlinx.coroutines.delay
-import me.saket.telephoto.flick.FlickToDismiss
-import me.saket.telephoto.flick.FlickToDismissState
-import me.saket.telephoto.flick.rememberFlickToDismissState
 import me.saket.telephoto.zoomable.ZoomSpec
 import me.saket.telephoto.zoomable.rememberZoomableState
 import timber.log.Timber
-import kotlin.time.Duration
 
 @Composable
 fun MediaViewerView(
@@ -289,22 +284,13 @@ private fun MediaViewerPage(
 ) {
     val currentShowOverlay by rememberUpdatedState(showOverlay)
     val currentOnShowOverlayChange by rememberUpdatedState(onShowOverlayChange)
-    val flickState = rememberFlickToDismissState(dismissThresholdRatio = 0.1f, rotateOnDrag = false)
 
-    DismissFlickEffects(
+    MediaViewerFlickToDismiss(
-        flickState = flickState,
+        onDismiss = onDismiss,
-        onDismissing = { animationDuration ->
-            delay(animationDuration / 3)
-            onDismiss()
-        },
         onDragging = {
             currentOnShowOverlayChange(false)
-        }
+        },
-    )
+        modifier = modifier,
-
-    FlickToDismiss(
-        state = flickState,
-        modifier = modifier.background(backgroundColorFor(flickState))
     ) {
         val downloadedMedia by data.downloadedMedia
         val showProgress = rememberShowProgress(downloadedMedia)
@@ -371,20 +357,9 @@ private fun MediaViewerLoadingPage(
     onDismiss: () -> Unit,
     modifier: Modifier = Modifier,
 ) {
-    val flickState = rememberFlickToDismissState(dismissThresholdRatio = 0.1f, rotateOnDrag = false)
+    MediaViewerFlickToDismiss(
-
+        onDismiss = onDismiss,
-    DismissFlickEffects(
+        modifier = modifier,
-        flickState = flickState,
-        onDismissing = { animationDuration ->
-            delay(animationDuration / 3)
-            onDismiss()
-        },
-        onDragging = {},
-    )
-
-    FlickToDismiss(
-        state = flickState,
-        modifier = modifier.background(backgroundColorFor(flickState))
     ) {
         Box(
             modifier = Modifier
@@ -403,20 +378,9 @@ private fun MediaViewerErrorPage(
     onDismiss: () -> Unit,
     modifier: Modifier = Modifier,
 ) {
-    val flickState = rememberFlickToDismissState(dismissThresholdRatio = 0.1f, rotateOnDrag = false)
+    MediaViewerFlickToDismiss(
-
+        onDismiss = onDismiss,
-    DismissFlickEffects(
+        modifier = modifier,
-        flickState = flickState,
-        onDismissing = { animationDuration ->
-            delay(animationDuration / 3)
-            onDismiss()
-        },
-        onDragging = {},
-    )
-
-    FlickToDismiss(
-        state = flickState,
-        modifier = modifier.background(backgroundColorFor(flickState))
     ) {
         Box(
             modifier = Modifier
@@ -432,30 +396,6 @@ private fun MediaViewerErrorPage(
     }
 }
 
-@Composable
-private fun DismissFlickEffects(
-    flickState: FlickToDismissState,
-    onDismissing: suspend (Duration) -> Unit,
-    onDragging: suspend () -> Unit,
-) {
-    val currentOnDismissing by rememberUpdatedState(onDismissing)
-    val currentOnDragging by rememberUpdatedState(onDragging)
-
-    when (val gestureState = flickState.gestureState) {
-        is FlickToDismissState.GestureState.Dismissing -> {
-            LaunchedEffect(Unit) {
-                currentOnDismissing(gestureState.animationDuration)
-            }
-        }
-        is FlickToDismissState.GestureState.Dragging -> {
-            LaunchedEffect(Unit) {
-                currentOnDragging()
-            }
-        }
-        else -> Unit
-    }
-}
-
 @Composable
 private fun rememberShowProgress(downloadedMedia: AsyncData<LocalMedia>): Boolean {
     var showProgress by remember {
@@ -623,21 +563,6 @@ private fun ErrorView(
     )
 }
 
-@Composable
-private fun backgroundColorFor(flickState: FlickToDismissState): Color {
-    val animatedAlpha by animateFloatAsState(
-        targetValue = when (flickState.gestureState) {
-            is FlickToDismissState.GestureState.Dismissed,
-            is FlickToDismissState.GestureState.Dismissing -> 0f
-            is FlickToDismissState.GestureState.Dragging,
-            is FlickToDismissState.GestureState.Idle,
-            is FlickToDismissState.GestureState.Resetting -> 1f - flickState.offsetFraction
-        },
-        label = "Background alpha",
-    )
-    return Color.Black.copy(alpha = animatedAlpha)
-}
-
 // Only preview in dark, dark theme is forced on the Node.
 @Preview
 @Composable