refactor: densité vivante, constante settle, tests de limite swipe-back

sharedUI/src/commonMain/kotlin/com/livrets/ui/SwipeBack.kt

@@ -21,11 +21,12 @@ import androidx.compose.ui.input.pointer.pointerInput
 import androidx.compose.ui.input.pointer.positionChange
 import androidx.compose.ui.input.pointer.util.VelocityTracker
 import androidx.compose.ui.layout.onSizeChanged
-import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.unit.dp
 import kotlin.math.abs
 import kotlinx.coroutines.launch
 
+private const val SettleMillis = 200
+
 object SwipeBackGesture {
     val EdgeZone = 24.dp
     const val CommitRatio = 0.4f
@@ -44,10 +45,8 @@ fun SwipeBack(
     background: @Composable () -> Unit,
     content: @Composable () -> Unit,
 ) {
-    val density = LocalDensity.current
     val scope = rememberCoroutineScope()
     val offset = remember { Animatable(0f) }
-    val edgeZonePx = with(density) { SwipeBackGesture.EdgeZone.toPx() }
     var widthPx by remember { mutableFloatStateOf(0f) }
     val showBackground by remember { derivedStateOf { offset.value > 0f } }
 
@@ -66,7 +65,7 @@ fun SwipeBack(
                 .pointerInput(Unit) {
                     awaitEachGesture {
                         val down = awaitFirstDown()
-                        if (down.position.x > edgeZonePx) return@awaitEachGesture
+                        if (down.position.x > SwipeBackGesture.EdgeZone.toPx()) return@awaitEachGesture
 
                         val tracker = VelocityTracker()
                         tracker.addPosition(down.uptimeMillis, down.position)
@@ -81,7 +80,7 @@ fun SwipeBack(
 
                             if (change.isConsumed && !change.pressed && change.previousPressed) {
                                 if (dragging) {
-                                    scope.launch { offset.animateTo(0f, tween(200)) }
+                                    scope.launch { offset.animateTo(0f, tween(SettleMillis)) }
                                 }
                                 break
                             }
@@ -116,7 +115,7 @@ fun SwipeBack(
                             if (change.changedToUpIgnoreConsumed()) {
                                 if (dragging) {
                                     val velocityDpPerSec =
-                                        tracker.calculateVelocity().x / density.density
+                                        tracker.calculateVelocity().x / density
                                     val commit = SwipeBackGesture.shouldCommit(
                                         offsetPx = dragged,
                                         containerWidthPx = widthPx,
@@ -125,11 +124,11 @@ fun SwipeBack(
                                     scope.launch {
                                         if (commit) {
                                             offset.snapTo(dragged)
-                                            offset.animateTo(widthPx, tween(200))
+                                            offset.animateTo(widthPx, tween(SettleMillis))
                                             onBack()
                                         } else {
                                             offset.snapTo(dragged)
-                                            offset.animateTo(0f, tween(200))
+                                            offset.animateTo(0f, tween(SettleMillis))
                                         }
                                     }
                                 }

sharedUI/src/commonTest/kotlin/com/livrets/ui/SwipeBackGestureTest.kt

@@ -49,4 +49,26 @@ class SwipeBackGestureTest {
             )
         )
     }
+
+    @Test
+    fun `pas de commit a la limite exacte de 40 pourcent sans velocite`() {
+        assertFalse(
+            SwipeBackGesture.shouldCommit(
+                offsetPx = 400f,
+                containerWidthPx = 1000f,
+                velocityDpPerSec = 0f,
+            )
+        )
+    }
+
+    @Test
+    fun `pas de commit avec un offset negatif`() {
+        assertFalse(
+            SwipeBackGesture.shouldCommit(
+                offsetPx = -100f,
+                containerWidthPx = 1000f,
+                velocityDpPerSec = 0f,
+            )
+        )
+    }
 }