1 files changed, 195 insertions, 0 deletions
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSystemStateListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSystemStateListener.java
new file mode 100644
index 0000000000..8b188438a4
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSystemStateListener.java
@@ -0,0 +1,195 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.content.res.Configuration;
+import android.database.ContentObserver;
+import android.hardware.input.InputManager;
+import android.net.Uri;
+import android.os.Handler;
+import android.os.Looper;
+import android.provider.Settings;
+import android.util.Log;
+import android.view.InputDevice;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.util.InputDeviceUtils;
+import org.mozilla.gecko.util.ThreadUtils;
+
+public class GeckoSystemStateListener implements InputManager.InputDeviceListener {
+  private static final String LOGTAG = "SystemStateListener";
+
+  private static final GeckoSystemStateListener listenerInstance = new GeckoSystemStateListener();
+
+  private boolean mInitialized;
+  private ContentObserver mContentObserver;
+  private static Context sApplicationContext;
+  private InputManager mInputManager;
+  private boolean mIsNightMode;
+
+  public static GeckoSystemStateListener getInstance() {
+    return listenerInstance;
+  }
+
+  private GeckoSystemStateListener() {}
+
+  public synchronized void initialize(final Context context) {
+    if (mInitialized) {
+      Log.w(LOGTAG, "Already initialized!");
+      return;
+    }
+    mInputManager = (InputManager) context.getSystemService(Context.INPUT_SERVICE);
+    mInputManager.registerInputDeviceListener(listenerInstance, ThreadUtils.getUiHandler());
+
+    sApplicationContext = context;
+    final ContentResolver contentResolver = sApplicationContext.getContentResolver();
+    final Uri animationSetting = Settings.System.getUriFor(Settings.Global.ANIMATOR_DURATION_SCALE);
+    mContentObserver =
+        new ContentObserver(new Handler(Looper.getMainLooper())) {
+          @Override
+          public void onChange(final boolean selfChange) {
+            onDeviceChanged();
+          }
+        };
+    contentResolver.registerContentObserver(animationSetting, false, mContentObserver);
+
+    final Uri invertSetting =
+        Settings.Secure.getUriFor(Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED);
+    contentResolver.registerContentObserver(invertSetting, false, mContentObserver);
+
+    final Uri textContrastSetting =
+        Settings.Secure.getUriFor(
+            /*Settings.Secure.ACCESSIBILITY_HIGH_TEXT_CONTRAST_ENABLED*/ "high_text_contrast_enabled");
+    contentResolver.registerContentObserver(textContrastSetting, false, mContentObserver);
+
+    mIsNightMode =
+        (sApplicationContext.getResources().getConfiguration().uiMode
+                & Configuration.UI_MODE_NIGHT_MASK)
+            == Configuration.UI_MODE_NIGHT_YES;
+
+    mInitialized = true;
+  }
+
+  public synchronized void shutdown() {
+    if (!mInitialized) {
+      Log.w(LOGTAG, "Already shut down!");
+      return;
+    }
+
+    if (mInputManager == null) {
+      Log.e(LOGTAG, "mInputManager should be valid!");
+      return;
+    }
+
+    mInputManager.unregisterInputDeviceListener(listenerInstance);
+
+    final ContentResolver contentResolver = sApplicationContext.getContentResolver();
+    contentResolver.unregisterContentObserver(mContentObserver);
+
+    mInitialized = false;
+    mInputManager = null;
+    mContentObserver = null;
+  }
+
+  @WrapForJNI(calledFrom = "gecko")
+  /**
+   * For prefers-reduced-motion media queries feature.
+   *
+   * <p>Uses `Settings.Global` which was introduced in API version 17.
+   */
+  private static boolean prefersReducedMotion() {
+    final ContentResolver contentResolver = sApplicationContext.getContentResolver();
+
+    return Settings.Global.getFloat(contentResolver, Settings.Global.ANIMATOR_DURATION_SCALE, 1)
+        == 0.0f;
+  }
+
+  @WrapForJNI(calledFrom = "gecko")
+  /**
+   * For inverted-colors queries feature.
+   *
+   * <p>Uses `Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED` which was introduced in API
+   * version 21.
+   */
+  private static boolean isInvertedColors() {
+    final ContentResolver contentResolver = sApplicationContext.getContentResolver();
+
+    return Settings.Secure.getInt(
+            contentResolver, Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED, 0)
+        == 1;
+  }
+
+  @WrapForJNI(calledFrom = "gecko")
+  /**
+   * For prefers-contrast queries feature.
+   *
+   * <p>Uses `Settings.Secure.ACCESSIBILITY_HIGH_TEXT_CONTRAST_ENABLED` which was introduced in API
+   * version 21.
+   */
+  private static boolean prefersContrast() {
+    final ContentResolver contentResolver = sApplicationContext.getContentResolver();
+
+    return Settings.Secure.getInt(
+            contentResolver, /*Settings.Secure.ACCESSIBILITY_HIGH_TEXT_CONTRAST_ENABLED*/
+            "high_text_contrast_enabled",
+            0)
+        == 1;
+  }
+
+  /** For prefers-color-scheme media queries feature. */
+  public boolean isNightMode() {
+    return mIsNightMode;
+  }
+
+  public void updateNightMode(final int newUIMode) {
+    final boolean isNightMode =
+        (newUIMode & Configuration.UI_MODE_NIGHT_MASK) == Configuration.UI_MODE_NIGHT_YES;
+    if (isNightMode == mIsNightMode) {
+      return;
+    }
+    mIsNightMode = isNightMode;
+    onDeviceChanged();
+  }
+
+  @WrapForJNI(stubName = "OnDeviceChanged", calledFrom = "any", dispatchTo = "gecko")
+  private static native void nativeOnDeviceChanged();
+
+  public static void onDeviceChanged() {
+    if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+      nativeOnDeviceChanged();
+    } else {
+      GeckoThread.queueNativeCallUntil(
+          GeckoThread.State.PROFILE_READY, GeckoSystemStateListener.class, "nativeOnDeviceChanged");
+    }
+  }
+
+  private void notifyDeviceChanged(final int deviceId) {
+    final InputDevice device = InputDevice.getDevice(deviceId);
+    if (device == null || !InputDeviceUtils.isPointerTypeDevice(device)) {
+      return;
+    }
+    onDeviceChanged();
+  }
+
+  @Override
+  public void onInputDeviceAdded(final int deviceId) {
+    notifyDeviceChanged(deviceId);
+  }
+
+  @Override
+  public void onInputDeviceRemoved(final int deviceId) {
+    // Call onDeviceChanged directly without checking device source types
+    // since we can no longer get a valid `InputDevice` in the case of
+    // device removal.
+    onDeviceChanged();
+  }
+
+  @Override
+  public void onInputDeviceChanged(final int deviceId) {
+    notifyDeviceChanged(deviceId);
+  }
+}