Create RotationChangeProvider in sysui

This allows to subscribe to rotation changes in a specific executor.
Raw usages of IRotationWatcher made the callback be received in a binder thread (not the main one).

Usages in child cls to make each small.

Bug: 241743859
Test: RotationChangeProviderTest
Change-Id: I2de074a3d5330d93b3d4cc2be1e60864a34ce6a6

packages/SystemUI/tests/src/com/android/systemui/unfold/updates/RotationChangeProviderTest.kt

@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2022 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.systemui.unfold.updates
+
+import android.testing.AndroidTestingRunner
+import android.view.IRotationWatcher
+import android.view.IWindowManager
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.unfold.updates.RotationChangeProvider.RotationListener
+import com.android.systemui.util.concurrency.FakeExecutor
+import com.android.systemui.util.time.FakeSystemClock
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.ArgumentCaptor
+import org.mockito.ArgumentMatchers.any
+import org.mockito.ArgumentMatchers.anyInt
+import org.mockito.Captor
+import org.mockito.Mock
+import org.mockito.Mockito.verify
+import org.mockito.Mockito.verifyNoMoreInteractions
+import org.mockito.MockitoAnnotations
+
+@RunWith(AndroidTestingRunner::class)
+@SmallTest
+class RotationChangeProviderTest : SysuiTestCase() {
+
+    private lateinit var rotationChangeProvider: RotationChangeProvider
+
+    @Mock lateinit var windowManagerInterface: IWindowManager
+    @Mock lateinit var listener: RotationListener
+    @Captor lateinit var rotationWatcher: ArgumentCaptor<IRotationWatcher>
+    private val fakeExecutor = FakeExecutor(FakeSystemClock())
+
+    @Before
+    fun setup() {
+        MockitoAnnotations.initMocks(this)
+        rotationChangeProvider =
+            RotationChangeProvider(windowManagerInterface, context, fakeExecutor)
+        rotationChangeProvider.addCallback(listener)
+        fakeExecutor.runAllReady()
+        verify(windowManagerInterface).watchRotation(rotationWatcher.capture(), anyInt())
+    }
+
+    @Test
+    fun onRotationChanged_rotationUpdated_listenerReceivesIt() {
+        sendRotationUpdate(42)
+
+        verify(listener).onRotationChanged(42)
+    }
+
+    @Test
+    fun onRotationChanged_subscribersRemoved_noRotationChangeReceived() {
+        sendRotationUpdate(42)
+        verify(listener).onRotationChanged(42)
+
+        rotationChangeProvider.removeCallback(listener)
+        fakeExecutor.runAllReady()
+        sendRotationUpdate(43)
+
+        verify(windowManagerInterface).removeRotationWatcher(any())
+        verifyNoMoreInteractions(listener)
+    }
+
+    private fun sendRotationUpdate(newRotation: Int) {
+        rotationWatcher.value.onRotationChanged(newRotation)
+        fakeExecutor.runAllReady()
+    }
+}

packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/RotationChangeProvider.kt

@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2022 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.systemui.unfold.updates
+
+import android.content.Context
+import android.os.RemoteException
+import android.view.IRotationWatcher
+import android.view.IWindowManager
+import android.view.Surface.Rotation
+import com.android.systemui.unfold.dagger.UnfoldMain
+import com.android.systemui.unfold.util.CallbackController
+import java.util.concurrent.Executor
+import javax.inject.Inject
+
+/**
+ * Allows to subscribe to rotation changes.
+ *
+ * This is needed as rotation updates from [IWindowManager] are received in a binder thread, while
+ * most of the times we want them in the main one. Updates are provided for the display associated
+ * to [context].
+ */
+class RotationChangeProvider
+@Inject
+constructor(
+    private val windowManagerInterface: IWindowManager,
+    private val context: Context,
+    @UnfoldMain private val mainExecutor: Executor,
+) : CallbackController<RotationChangeProvider.RotationListener> {
+
+    private val listeners = mutableListOf<RotationListener>()
+
+    private val rotationWatcher = RotationWatcher()
+
+    override fun addCallback(listener: RotationListener) {
+        mainExecutor.execute {
+            if (listeners.isEmpty()) {
+                subscribeToRotation()
+            }
+            listeners += listener
+        }
+    }
+
+    override fun removeCallback(listener: RotationListener) {
+        mainExecutor.execute {
+            listeners -= listener
+            if (listeners.isEmpty()) {
+                unsubscribeToRotation()
+            }
+        }
+    }
+
+    private fun subscribeToRotation() {
+        try {
+            windowManagerInterface.watchRotation(rotationWatcher, context.displayId)
+        } catch (e: RemoteException) {
+            throw e.rethrowFromSystemServer()
+        }
+    }
+
+    private fun unsubscribeToRotation() {
+        try {
+            windowManagerInterface.removeRotationWatcher(rotationWatcher)
+        } catch (e: RemoteException) {
+            throw e.rethrowFromSystemServer()
+        }
+    }
+
+    /** Gets notified of rotation changes. */
+    fun interface RotationListener {
+        /** Called once rotation changes. */
+        fun onRotationChanged(@Rotation newRotation: Int)
+    }
+
+    private inner class RotationWatcher : IRotationWatcher.Stub() {
+        override fun onRotationChanged(rotation: Int) {
+            mainExecutor.execute { listeners.forEach { it.onRotationChanged(rotation) } }
+        }
+    }
+}