Implement drag then snap flicker test

Add a flicker test for dragging the pip window
away from the edge and verifying that it snaps
back to that same edge

Bug: 264555500

Test: atest WMShellFlickerTests:PipDragThenSnapTest
Change-Id: I3397f7f47198b33f4d0250704ef5f2fd54446517
(cherry picked from commit d389b97058)

libs/WindowManager/Shell/tests/flicker/src/com/android/wm/shell/flicker/pip/PipDragThenSnapTest.kt

@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.wm.shell.flicker.pip
+
+import android.platform.test.annotations.Postsubmit
+import android.tools.common.Rotation
+import android.tools.device.flicker.junit.FlickerParametersRunnerFactory
+import android.graphics.Rect
+import android.tools.device.flicker.legacy.FlickerBuilder
+import android.tools.device.flicker.legacy.FlickerTest
+import android.tools.device.flicker.legacy.FlickerTestFactory
+import android.tools.device.flicker.rules.RemoveAllTasksButHomeRule
+import androidx.test.filters.RequiresDevice
+import com.android.server.wm.flicker.helpers.setRotation
+import com.android.server.wm.flicker.testapp.ActivityOptions
+import org.junit.FixMethodOrder
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.junit.runners.MethodSorters
+import org.junit.runners.Parameterized
+
+/**
+ * Test the snapping of a PIP window via dragging, releasing, and checking its final location.
+ */
+@RequiresDevice
+@RunWith(Parameterized::class)
+@Parameterized.UseParametersRunnerFactory(FlickerParametersRunnerFactory::class)
+@FixMethodOrder(MethodSorters.NAME_ASCENDING)
+class PipDragThenSnapTest(flicker: FlickerTest) : PipTransition(flicker){
+    override val transition: FlickerBuilder.() -> Unit
+        get() = {
+            val stringExtras: Map<String, String> =
+                mapOf(ActivityOptions.Pip.EXTRA_ENTER_PIP to "true")
+
+            // cache the starting bounds here
+            val startBounds = Rect()
+
+            setup {
+                // Launch the PIP activity and wait for it to enter PiP mode
+                setRotation(Rotation.ROTATION_0)
+                RemoveAllTasksButHomeRule.removeAllTasksButHome()
+                pipApp.launchViaIntentAndWaitForPip(wmHelper, stringExtras = stringExtras)
+
+                val initRegion = pipApp.dragPipWindowAwayFromEdge(wmHelper, 50)
+                startBounds
+                    .set(initRegion.left, initRegion.top, initRegion.right, initRegion.bottom)
+            }
+            transitions {
+                // continue the transition until the PIP snaps
+                pipApp.waitForPipToSnapTo(wmHelper, startBounds)
+            }
+        }
+
+    /** Checks that the visible region area of [pipApp] always moves right during the animation. */
+    @Postsubmit
+    @Test
+    fun pipLayerMovesRight() {
+        flicker.assertLayers {
+            val pipLayerList = layers { pipApp.layerMatchesAnyOf(it) && it.isVisible }
+            pipLayerList.zipWithNext { previous, current ->
+                current.visibleRegion.isToTheRight(previous.visibleRegion.region)
+            }
+        }
+    }
+
+    companion object {
+        /**
+         * Creates the test configurations.
+         *
+         * See [FlickerTestFactory.nonRotationTests] for configuring screen orientation and
+         * navigation modes.
+         */
+        @Parameterized.Parameters(name = "{0}")
+        @JvmStatic
+        fun getParams(): List<FlickerTest> {
+            return FlickerTestFactory.nonRotationTests(
+                supportedRotations = listOf(Rotation.ROTATION_0)
+            )
+        }
+    }
+}

tests/FlickerTests/src/com/android/server/wm/flicker/helpers/PipAppHelper.kt

@@ -58,7 +58,51 @@ open class PipAppHelper(instrumentation: Instrumentation) :
     }
 
     /**
-     * Expands the PIP window my using the pinch out gesture.
+     * Drags the PIP window away from the screen edge while not crossing the display center.
+     *
+     * @throws IllegalStateException if default display bounds are not available
+     * @return initial bounds of the PIP window
+     */
+    fun dragPipWindowAwayFromEdge(wmHelper: WindowManagerStateHelper, steps: Int): Rect {
+        val initWindowRect = getWindowRect(wmHelper).clone()
+
+        // initial pointer at the center of the window
+        val startX = initWindowRect.centerX()
+        val y = initWindowRect.centerY()
+
+        val displayRect = wmHelper.currentState.wmState.getDefaultDisplay()?.displayRect
+                ?: throw IllegalStateException("Default display is null")
+
+        // the offset to the right of the display center to drag the window to
+        val offset = 20
+
+        // the actual final x coordinate with the offset included
+        // if the pip window is closer to the right edge of the display the offset is positive
+        // otherwise the offset is negative
+        val endX = displayRect.centerX() + offset * (if (isCloserToRightEdge(wmHelper)) 1 else -1)
+
+        // drag the window to the left but not beyond the center of the display
+        uiDevice.drag(startX, y, endX, y, steps)
+
+        return initWindowRect
+    }
+
+    /**
+     * Returns true if PIP window is closer to the right edge of the display than left.
+     *
+     * @throws IllegalStateException if default display bounds are not available
+     */
+    private fun isCloserToRightEdge(wmHelper: WindowManagerStateHelper): Boolean {
+        val windowRect = getWindowRect(wmHelper)
+
+        val displayRect = wmHelper.currentState.wmState.getDefaultDisplay()?.displayRect
+                ?: throw IllegalStateException("Default display is null")
+
+        return windowRect.centerX() > displayRect.centerX()
+    }
+
+    /**
+     * Expands the PIP window by using the pinch out gesture.
      *
      * @param percent The percentage by which to increase the pip window size.
      * @throws IllegalArgumentException if percentage isn't between 0.0f and 1.0f
@@ -106,7 +150,7 @@ open class PipAppHelper(instrumentation: Instrumentation) :
     }
 
     /**
-     * Minimizes the PIP window my using the pinch in gesture.
+     * Minimizes the PIP window by using the pinch in gesture.
      *
      * @param percent The percentage by which to decrease the pip window size.
      * @throws IllegalArgumentException if percentage isn't between 0.0f and 1.0f
@@ -307,6 +351,27 @@ open class PipAppHelper(instrumentation: Instrumentation) :
             .waitForAndVerify()
     }
 
+    /**
+     * Waits until the PIP window snaps horizontally to the provided bounds.
+     *
+     * @param finalRightX the final x coordinate of the right edge of the pip window
+     */
+    fun waitForPipToSnapTo(wmHelper: WindowManagerStateHelper, finalBounds: android.graphics.Rect) {
+        wmHelper
+            .StateSyncBuilder()
+            .add("pipWindowSnapped") {
+                val pipAppWindow =
+                    it.wmState.visibleWindows.firstOrNull { window ->
+                        this.windowMatchesAnyOf(window)
+                    }
+                        ?: return@add false
+                val pipRegionBounds = pipAppWindow.frameRegion.bounds
+                return@add pipRegionBounds.left == finalBounds.left &&
+                    pipRegionBounds.right == finalBounds.right
+            }
+            .waitForAndVerify()
+    }
+
     companion object {
         private const val TAG = "PipAppHelper"
         private const val ENTER_PIP_BUTTON_ID = "enter_pip"