[Media] Add a MediaController.Callback that will disconnect us when

onSessionDestroyed is triggered.

Bug: 225403871
Test: ResumeMediaBrowserTest
Change-Id: I2626a6af7d09f12184b2dda88b28838b51a247c6

packages/SystemUI/src/com/android/systemui/media/ResumeMediaBrowser.java

@@ -52,8 +52,10 @@ public class ResumeMediaBrowser {
     private final MediaBrowserFactory mBrowserFactory;
     private final ResumeMediaBrowserLogger mLogger;
     private final ComponentName mComponentName;
+    private final MediaController.Callback mMediaControllerCallback = new SessionDestroyCallback();
 
     private MediaBrowser mMediaBrowser;
+    @Nullable private MediaController mMediaController;
 
     /**
      * Initialize a new media browser
@@ -90,6 +92,7 @@ public class ResumeMediaBrowser {
                 mComponentName,
                 mConnectionCallback,
                 rootHints);
+        updateMediaController();
         mLogger.logConnection(mComponentName, "findRecentMedia");
         mMediaBrowser.connect();
     }
@@ -154,7 +157,8 @@ public class ResumeMediaBrowser {
         @Override
         public void onConnected() {
             Log.d(TAG, "Service connected for " + mComponentName);
-            if (mMediaBrowser != null && mMediaBrowser.isConnected()) {
+            updateMediaController();
+            if (isBrowserConnected()) {
                 String root = mMediaBrowser.getRoot();
                 if (!TextUtils.isEmpty(root)) {
                     if (mCallback != null) {
@@ -207,6 +211,7 @@ public class ResumeMediaBrowser {
             mMediaBrowser.disconnect();
         }
         mMediaBrowser = null;
+        updateMediaController();
     }
 
     /**
@@ -225,7 +230,8 @@ public class ResumeMediaBrowser {
                     @Override
                     public void onConnected() {
                         Log.d(TAG, "Connected for restart " + mMediaBrowser.isConnected());
-                        if (mMediaBrowser == null || !mMediaBrowser.isConnected()) {
+                        updateMediaController();
+                        if (!isBrowserConnected()) {
                             if (mCallback != null) {
                                 mCallback.onError();
                             }
@@ -259,6 +265,7 @@ public class ResumeMediaBrowser {
                         disconnect();
                     }
                 }, rootHints);
+        updateMediaController();
         mLogger.logConnection(mComponentName, "restart");
         mMediaBrowser.connect();
     }
@@ -273,7 +280,7 @@ public class ResumeMediaBrowser {
      * @return the token, or null if the MediaBrowser is null or disconnected
      */
     public MediaSession.Token getToken() {
-        if (mMediaBrowser == null || !mMediaBrowser.isConnected()) {
+        if (!isBrowserConnected()) {
             return null;
         }
         return mMediaBrowser.getSessionToken();
@@ -305,10 +312,39 @@ public class ResumeMediaBrowser {
                 mComponentName,
                 mConnectionCallback,
                 rootHints);
+        updateMediaController();
         mLogger.logConnection(mComponentName, "testConnection");
         mMediaBrowser.connect();
     }
 
+    /** Updates mMediaController based on our current browser values. */
+    private void updateMediaController() {
+        MediaSession.Token controllerToken =
+                mMediaController != null ? mMediaController.getSessionToken() : null;
+        MediaSession.Token currentToken = getToken();
+        boolean areEqual = (controllerToken == null && currentToken == null)
+                || (controllerToken != null && controllerToken.equals(currentToken));
+        if (areEqual) {
+            return;
+        }
+
+        // Whenever the token changes, un-register the callback on the old controller (if we have
+        // one) and create a new controller with the callback attached.
+        if (mMediaController != null) {
+            mMediaController.unregisterCallback(mMediaControllerCallback);
+        }
+        if (currentToken != null) {
+            mMediaController = createMediaController(currentToken);
+            mMediaController.registerCallback(mMediaControllerCallback);
+        } else {
+            mMediaController = null;
+        }
+    }
+
+    private boolean isBrowserConnected() {
+        return mMediaBrowser != null && mMediaBrowser.isConnected();
+    }
+
     /**
      * Interface to handle results from ResumeMediaBrowser
      */
@@ -335,4 +371,12 @@ public class ResumeMediaBrowser {
                 ResumeMediaBrowser browser) {
         }
     }
+
+    private class SessionDestroyCallback extends MediaController.Callback {
+        @Override
+        public void onSessionDestroyed() {
+            mLogger.logSessionDestroyed(isBrowserConnected(), mComponentName);
+            disconnect();
+        }
+    }
 }

packages/SystemUI/src/com/android/systemui/media/ResumeMediaBrowserLogger.kt

@@ -48,6 +48,27 @@ class ResumeMediaBrowserLogger @Inject constructor(
         },
         { "Disconnecting browser for component $str1" }
     )
+
+    /**
+     * Logs that we received a [android.media.session.MediaController.Callback.onSessionDestroyed]
+     * event.
+     *
+     * @param isBrowserConnected true if there's a currently connected
+     *     [android.media.browse.MediaBrowser] and false otherwise.
+     * @param componentName the component name for the [ResumeMediaBrowser] that triggered this log.
+     */
+    fun logSessionDestroyed(
+        isBrowserConnected: Boolean,
+        componentName: ComponentName
+    ) = buffer.log(
+        TAG,
+        LogLevel.DEBUG,
+        {
+            bool1 = isBrowserConnected
+            str1 = componentName.toShortString()
+        },
+        { "Session destroyed. Active browser = $bool1. Browser component = $str1." }
+    )
 }
 
 private const val TAG = "MediaBrowser"

packages/SystemUI/tests/src/com/android/systemui/media/ResumeMediaBrowserTest.kt

@@ -35,6 +35,7 @@ import org.mockito.ArgumentCaptor
 import org.mockito.Captor
 import org.mockito.Mock
 import org.mockito.Mockito
+import org.mockito.Mockito.reset
 import org.mockito.Mockito.verify
 import org.mockito.MockitoAnnotations
 import org.mockito.Mockito.`when` as whenever
@@ -73,6 +74,7 @@ public class ResumeMediaBrowserTest : SysuiTestCase() {
 
     @Captor lateinit var connectionCallback: ArgumentCaptor<MediaBrowser.ConnectionCallback>
     @Captor lateinit var subscriptionCallback: ArgumentCaptor<MediaBrowser.SubscriptionCallback>
+    @Captor lateinit var mediaControllerCallback: ArgumentCaptor<MediaController.Callback>
 
     @Before
     fun setUp() {
@@ -82,6 +84,7 @@ public class ResumeMediaBrowserTest : SysuiTestCase() {
                 .thenReturn(browser)
 
         whenever(mediaController.transportControls).thenReturn(transportControls)
+        whenever(mediaController.sessionToken).thenReturn(token)
 
         resumeBrowser = TestableResumeMediaBrowser(
             context,
@@ -136,6 +139,22 @@ public class ResumeMediaBrowserTest : SysuiTestCase() {
         verify(callback).addTrack(eq(description), eq(component), eq(resumeBrowser))
     }
 
+    @Test
+    fun testConnection_thenSessionDestroyed_disconnects() {
+        // When testConnection is called and we connect successfully
+        setupBrowserConnection()
+        resumeBrowser.testConnection()
+        verify(mediaController).registerCallback(mediaControllerCallback.capture())
+        reset(browser)
+
+        // And a sessionDestroyed event is triggered
+        mediaControllerCallback.value.onSessionDestroyed()
+
+        // Then we disconnect the browser and unregister the callback
+        verify(browser).disconnect()
+        verify(mediaController).unregisterCallback(mediaControllerCallback.value)
+    }
+
     @Test
     fun testConnection_calledTwice_oldBrowserDisconnected() {
         val oldBrowser = mock<MediaBrowser>()
@@ -187,6 +206,22 @@ public class ResumeMediaBrowserTest : SysuiTestCase() {
         verify(callback).onConnected()
     }
 
+    @Test
+    fun testFindRecentMedia_thenSessionDestroyed_disconnects() {
+        // When findRecentMedia is called and we connect successfully
+        setupBrowserConnection()
+        resumeBrowser.findRecentMedia()
+        verify(mediaController).registerCallback(mediaControllerCallback.capture())
+        reset(browser)
+
+        // And a sessionDestroyed event is triggered
+        mediaControllerCallback.value.onSessionDestroyed()
+
+        // Then we disconnect the browser and unregister the callback
+        verify(browser).disconnect()
+        verify(mediaController).unregisterCallback(mediaControllerCallback.value)
+    }
+
     @Test
     fun testFindRecentMedia_calledTwice_oldBrowserDisconnected() {
         val oldBrowser = mock<MediaBrowser>()
@@ -260,6 +295,22 @@ public class ResumeMediaBrowserTest : SysuiTestCase() {
         verify(transportControls).play()
     }
 
+    @Test
+    fun testRestart_thenSessionDestroyed_disconnects() {
+        // When restart is called and we connect successfully
+        setupBrowserConnection()
+        resumeBrowser.restart()
+        verify(mediaController).registerCallback(mediaControllerCallback.capture())
+        reset(browser)
+
+        // And a sessionDestroyed event is triggered
+        mediaControllerCallback.value.onSessionDestroyed()
+
+        // Then we disconnect the browser and unregister the callback
+        verify(browser).disconnect()
+        verify(mediaController).unregisterCallback(mediaControllerCallback.value)
+    }
+
     @Test
     fun testRestart_calledTwice_oldBrowserDisconnected() {
         val oldBrowser = mock<MediaBrowser>()