fix(helper): report denied clipboard writes so text input can fall back

packages/artemis-accessibility-helper/app/src/main/java/com/artemis/helper/GestureController.java

@@ -2,6 +2,8 @@
 
 import android.accessibilityservice.AccessibilityService;
 import android.accessibilityservice.GestureDescription;
+import android.app.ActivityManager;
+import android.app.AppOpsManager;
 import android.content.ClipData;
 import android.content.ClipboardManager;
 import android.content.Context;
@@ -198,12 +200,18 @@ public void onCancelled(GestureDescription gestureDescription) {
     }
 
     /**
-     * Write text to the system clipboard. Clipboard writes are allowed from any
-     * app on every API level (only reads are restricted since Android 10), so this
-     * is the IME-free path the host uses for multiline and non-ASCII input:
-     * set the clip here, then KEYCODE_PASTE over adb.
+     * Write text to the system clipboard. This is the IME-free path the host uses
+     * for multiline and non-ASCII input: set the clip here, then KEYCODE_PASTE over
+     * adb. Some OEM builds restrict WRITE_CLIPBOARD to the foreground via AppOps,
+     * and ClipboardService then drops the write without throwing, so the mode is
+     * checked first; returning false lets the host fall back to another input path
+     * instead of pasting stale clipboard contents.
      */
     public static boolean setClipboard(final AccessibilityService service, final String text) {
+        if (!isClipboardWriteAllowed(service)) {
+            Log.w(TAG, "setClipboard skipped: WRITE_CLIPBOARD is not allowed for this process");
+            return false;
+        }
         final CountDownLatch latch = new CountDownLatch(1);
         final AtomicBoolean ok = new AtomicBoolean(false);
         MAIN_HANDLER.post(new Runnable() {
@@ -229,4 +237,33 @@ public void run() {
         }
         return ok.get();
     }
+
+    private static final String OPSTR_WRITE_CLIPBOARD = "android:write_clipboard";
+    // AppOpsManager.MODE_FOREGROUND, which only exists as a constant from API 29.
+    private static final int MODE_FOREGROUND = 4;
+
+    private static boolean isClipboardWriteAllowed(Context context) {
+        AppOpsManager appOps = (AppOpsManager) context.getSystemService(Context.APP_OPS_SERVICE);
+        if (appOps == null) return true;
+        int mode;
+        try {
+            int uid = android.os.Process.myUid();
+            String pkg = context.getPackageName();
+            mode = Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q
+                    ? appOps.unsafeCheckOpNoThrow(OPSTR_WRITE_CLIPBOARD, uid, pkg)
+                    : appOps.checkOpNoThrow(OPSTR_WRITE_CLIPBOARD, uid, pkg);
+        } catch (RuntimeException e) {
+            // Unknown op name on this build: keep the previous optimistic behaviour.
+            return true;
+        }
+        if (mode == AppOpsManager.MODE_ALLOWED || mode == AppOpsManager.MODE_DEFAULT) return true;
+        if (mode == MODE_FOREGROUND) return isProcessForeground();
+        return false;
+    }
+
+    private static boolean isProcessForeground() {
+        ActivityManager.RunningAppProcessInfo info = new ActivityManager.RunningAppProcessInfo();
+        ActivityManager.getMyMemoryState(info);
+        return info.importance <= ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND_SERVICE;
+    }
 }

tests/unit/test_drivers.py

@@ -101,6 +101,35 @@ async def test_android_driver_with_mock_adb():
     mock_adb_device.shell.assert_called_with("input keyevent 4")
 
 
+@pytest.mark.asyncio
+async def test_android_input_text_falls_back_to_adbkeyboard_when_clipboard_rejected():
+    """A rejected clipboard write must not paste; ADBKeyboard should receive the text."""
+    mock_adb_client = MagicMock()
+    mock_adb_device = MagicMock()
+    mock_adb_client.device.return_value = mock_adb_device
+    mock_adb_device.shell.side_effect = lambda cmd: (
+        "com.android.adbkeyboard/.AdbIME"
+        if cmd == "settings get secure default_input_method"
+        else ""
+    )
+    mock_ui_client = MagicMock()
+    mock_ui_client.set_clipboard.return_value = False
+
+    driver = AndroidAdbDriver(
+        device_id="emulator-5554",
+        adb_client=mock_adb_client,
+        ui_adb_client=mock_ui_client,
+    )
+
+    assert await driver.input_text("你好", clear_existing=False) is True
+
+    commands = [call.args[0] for call in mock_adb_device.shell.call_args_list]
+    mock_ui_client.set_clipboard.assert_called_once_with("你好")
+    assert "input keyevent 279" not in commands
+    b64_text = base64.b64encode("你好".encode()).decode("utf-8")
+    assert f"am broadcast -a ADB_INPUT_B64 --es msg '{b64_text}'" in commands
+
+
 @pytest.mark.asyncio
 async def test_android_driver_preserves_elements_from_combined_screen_data():
     """The combined uiautomator2 response is the authoritative live snapshot."""