Refactor MainService to prevent unnecessary activity starts

There should be no logic change. Just moving the code in separate methods
and directly check the condition instead of checking in the activity.

Most of the time this will safe jumping between activities and service
as permissions are only requested the first time.
This helps when automating the start process of a session.

Author: Niels-Be

app/src/main/java/net/christianbeier/droidvnc_ng/MainService.java

@@ -21,6 +21,7 @@
 
 package net.christianbeier.droidvnc_ng;
 
+import android.Manifest;
 import android.annotation.SuppressLint;
 import android.app.Notification;
 import android.app.NotificationChannel;
@@ -31,6 +32,7 @@
 import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
+import android.content.pm.PackageManager;
 import android.content.pm.ServiceInfo;
 import android.net.ConnectivityManager;
 import android.net.Network;
@@ -353,36 +355,7 @@ public int onStartCommand(Intent intent, int flags, int startId)
                 stopScreenCapture();
                 startScreenCapture();
             } else {
-                DisplayMetrics displayMetrics = Utils.getDisplayMetrics(this, Display.DEFAULT_DISPLAY);
-                Intent startIntent = Objects.requireNonNull(MainServicePersistData.loadStartIntent(this));
-                int port = startIntent.getIntExtra(EXTRA_PORT, PreferenceManager.getDefaultSharedPreferences(this).getInt(Constants.PREFS_KEY_SETTINGS_PORT, mDefaults.getPort()));
-                String password = startIntent.getStringExtra(EXTRA_PASSWORD) != null ? startIntent.getStringExtra(EXTRA_PASSWORD) : PreferenceManager.getDefaultSharedPreferences(this).getString(Constants.PREFS_KEY_SETTINGS_PASSWORD, mDefaults.getPassword());
-                // get device name
-                String name = Utils.getDeviceName(this);
-
-                boolean status = vncStartServer(displayMetrics.widthPixels,
-                        displayMetrics.heightPixels,
-                        port,
-                        name,
-                        password,
-                        getFilesDir().getAbsolutePath() + File.separator + "novnc");
-                Intent answer = new Intent(ACTION_START);
-                answer.putExtra(EXTRA_REQUEST_ID, startIntent.getStringExtra(EXTRA_REQUEST_ID));
-                answer.putExtra(EXTRA_REQUEST_SUCCESS, status);
-                sendBroadcastToOthersAndUs(answer);
-
-                if (status) {
-                    MainServicePersistData.saveLastActiveState(this, true);
-                    startScreenCapture();
-                    registerNSD(name, port);
-                    updateNotification();
-                    // if we got here, we want to restart if we were killed
-                    return START_REDELIVER_INTENT;
-                } else {
-                    MainServicePersistData.clear(this);
-                    stopSelfByUs();
-                    return START_NOT_STICKY;
-                }
+                return step4StartCapture();
             }
         }
 
@@ -399,69 +372,14 @@ public int onStartCommand(Intent intent, int flags, int startId)
                 // or ask for capturing permission first (then going in step 4)
             }
 
-            Intent startIntent = Objects.requireNonNull(MainServicePersistData.loadStartIntent(this));
-
-            if (mResultCode != 0 && mResultData != null
-                    || (Build.VERSION.SDK_INT >= 30 && startIntent.getBooleanExtra(EXTRA_FALLBACK_SCREEN_CAPTURE, false))) {
-                DisplayMetrics displayMetrics = Utils.getDisplayMetrics(this, Display.DEFAULT_DISPLAY);
-                int port = startIntent.getIntExtra(EXTRA_PORT, PreferenceManager.getDefaultSharedPreferences(this).getInt(Constants.PREFS_KEY_SETTINGS_PORT, mDefaults.getPort()));
-                String password = startIntent.getStringExtra(EXTRA_PASSWORD) != null ? startIntent.getStringExtra(EXTRA_PASSWORD) : PreferenceManager.getDefaultSharedPreferences(this).getString(Constants.PREFS_KEY_SETTINGS_PASSWORD, mDefaults.getPassword());
-                String name = Utils.getDeviceName(this);
-                boolean status = vncStartServer(displayMetrics.widthPixels,
-                        displayMetrics.heightPixels,
-                        port,
-                        name,
-                        password,
-                        getFilesDir().getAbsolutePath() + File.separator + "novnc");
-
-                Intent answer = new Intent(ACTION_START);
-                answer.putExtra(EXTRA_REQUEST_ID, startIntent.getStringExtra(EXTRA_REQUEST_ID));
-                answer.putExtra(EXTRA_REQUEST_SUCCESS, status);
-                sendBroadcastToOthersAndUs(answer);
-
-                if(status) {
-                    MainServicePersistData.saveLastActiveState(this, true);
-                    startScreenCapture();
-                    registerNSD(name, port);
-                    updateNotification();
-                    // if we got here, we want to restart if we were killed
-                    return START_REDELIVER_INTENT;
-                } else {
-                    MainServicePersistData.clear(this);
-                    stopSelfByUs();
-                    return START_NOT_STICKY;
-                }
-            } else {
-                Log.i(TAG, "Requesting confirmation");
-                // This initiates a prompt dialog for the user to confirm screen projection.
-                Intent mediaProjectionRequestIntent = new Intent(this, MediaProjectionRequestActivity.class);
-                mediaProjectionRequestIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-                startActivity(mediaProjectionRequestIntent);
-                // if screen capturing was not started, we don't want a restart if we were killed
-                // especially, we don't want the permission asking to replay.
-                return START_NOT_STICKY;
-            }
+            return step3RequestProjectionPermission();
         }
 
         if(ACTION_HANDLE_INPUT_RESULT.equals(intent.getAction()) && MainServicePersistData.loadStartIntent(this) != null) {
             Log.d(TAG, "onStartCommand: handle input result");
             // Step 2: coming back from input permission check, now setup InputService and ask for write storage permission or notification permission
             InputService.isInputEnabled = intent.getBooleanExtra(EXTRA_INPUT_RESULT, false);
-            if(Build.VERSION.SDK_INT < 33) {
-                Intent writeStorageRequestIntent = new Intent(this, WriteStorageRequestActivity.class);
-                writeStorageRequestIntent.putExtra(
-                        EXTRA_FILE_TRANSFER,
-                        Objects.requireNonNull(MainServicePersistData.loadStartIntent(this)).getBooleanExtra(EXTRA_FILE_TRANSFER, PreferenceManager.getDefaultSharedPreferences(this).getBoolean(Constants.PREFS_KEY_SETTINGS_FILE_TRANSFER, mDefaults.getFileTransfer())));
-                writeStorageRequestIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-                startActivity(writeStorageRequestIntent);
-            } else {
-                Intent notificationRequestIntent = new Intent(this, NotificationRequestActivity.class);
-                notificationRequestIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-                startActivity(notificationRequestIntent);
-            }
-            // if screen capturing was not started, we don't want a restart if we were killed
-            // especially, we don't want the permission asking to replay.
-            return START_NOT_STICKY;
+            return step2RequestStorageOrNotifications();
         }
 
         if(ACTION_START.equals(intent.getAction())) {
@@ -487,13 +405,7 @@ public int onStartCommand(Intent intent, int flags, int startId)
             InputService.scaling = PreferenceManager.getDefaultSharedPreferences(this).getFloat(Constants.PREFS_KEY_SERVER_LAST_SCALING, new Defaults(this).getScaling());
 
             // Step 1: check input/start-on-boot permission
-            Intent inputRequestIntent = new Intent(this, InputRequestActivity.class);
-            inputRequestIntent.putExtra(EXTRA_VIEW_ONLY, intent.getBooleanExtra(EXTRA_VIEW_ONLY, mDefaults.getViewOnly()));
-            inputRequestIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-            startActivity(inputRequestIntent);
-            // if screen capturing was not started, we don't want a restart if we were killed
-            // especially, we don't want the permission asking to replay.
-            return START_NOT_STICKY;
+            return step1ConnectInputService(intent.getBooleanExtra(EXTRA_VIEW_ONLY, mDefaults.getViewOnly()));
         }
 
         if(ACTION_STOP.equals(intent.getAction())) {
@@ -567,6 +479,99 @@ public int onStartCommand(Intent intent, int flags, int startId)
         return START_NOT_STICKY;
     }
 
+    private int step1ConnectInputService(boolean viewOnly) {
+        if (!InputService.isConnected()) {
+            Intent inputRequestIntent = new Intent(this, InputRequestActivity.class);
+            inputRequestIntent.putExtra(EXTRA_VIEW_ONLY, viewOnly);
+            inputRequestIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+            startActivity(inputRequestIntent);
+            // if screen capturing was not started, we don't want a restart if we were killed
+            // especially, we don't want the permission asking to replay.
+            return START_NOT_STICKY;
+        } else {
+            InputService.isInputEnabled = true;
+            return step2RequestStorageOrNotifications();
+        }
+    }
+
+    private int step2RequestStorageOrNotifications() {
+        if (Build.VERSION.SDK_INT < 33) {
+            if (checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED &&
+                    !PreferenceManager.getDefaultSharedPreferences(this).getBoolean(WriteStorageRequestActivity.PREFS_KEY_PERMISSION_ASKED_BEFORE, false)) {
+                Intent writeStorageRequestIntent = new Intent(this, WriteStorageRequestActivity.class);
+                writeStorageRequestIntent.putExtra(
+                        EXTRA_FILE_TRANSFER,
+                        Objects.requireNonNull(MainServicePersistData.loadStartIntent(this)).getBooleanExtra(EXTRA_FILE_TRANSFER, PreferenceManager.getDefaultSharedPreferences(this).getBoolean(Constants.PREFS_KEY_SETTINGS_FILE_TRANSFER, mDefaults.getFileTransfer())));
+                writeStorageRequestIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+                startActivity(writeStorageRequestIntent);
+            } else {
+                return step3RequestProjectionPermission();
+            }
+        } else {
+            if (checkSelfPermission(Manifest.permission.POST_NOTIFICATIONS) != PackageManager.PERMISSION_GRANTED &&
+                    !PreferenceManager.getDefaultSharedPreferences(this).getBoolean(NotificationRequestActivity.PREFS_KEY_POST_NOTIFICATION_PERMISSION_ASKED_BEFORE, false)) {
+                Intent notificationRequestIntent = new Intent(this, NotificationRequestActivity.class);
+                notificationRequestIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+                startActivity(notificationRequestIntent);
+            } else {
+                return step3RequestProjectionPermission();
+            }
+        }
+        // if screen capturing was not started, we don't want a restart if we were killed
+        // especially, we don't want the permission asking to replay.
+        return START_NOT_STICKY;
+    }
+
+    private int step3RequestProjectionPermission() {
+        Intent startIntent = Objects.requireNonNull(MainServicePersistData.loadStartIntent(this));
+
+        if (mResultCode != 0 && mResultData != null
+                || (Build.VERSION.SDK_INT >= 30 && startIntent.getBooleanExtra(EXTRA_FALLBACK_SCREEN_CAPTURE, false))) {
+            return step4StartCapture();
+        } else {
+            Log.i(TAG, "Requesting confirmation");
+            // This initiates a prompt dialog for the user to confirm screen projection.
+            Intent mediaProjectionRequestIntent = new Intent(this, MediaProjectionRequestActivity.class);
+            mediaProjectionRequestIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+            startActivity(mediaProjectionRequestIntent);
+            // if screen capturing was not started, we don't want a restart if we were killed
+            // especially, we don't want the permission asking to replay.
+            return START_NOT_STICKY;
+        }
+    }
+
+    private int step4StartCapture() {
+        DisplayMetrics displayMetrics = Utils.getDisplayMetrics(this, Display.DEFAULT_DISPLAY);
+        Intent startIntent = Objects.requireNonNull(MainServicePersistData.loadStartIntent(this));
+        int port = startIntent.getIntExtra(EXTRA_PORT, PreferenceManager.getDefaultSharedPreferences(this).getInt(Constants.PREFS_KEY_SETTINGS_PORT, mDefaults.getPort()));
+        String password = startIntent.getStringExtra(EXTRA_PASSWORD) != null ? startIntent.getStringExtra(EXTRA_PASSWORD) : PreferenceManager.getDefaultSharedPreferences(this).getString(Constants.PREFS_KEY_SETTINGS_PASSWORD, mDefaults.getPassword());
+        String name = Utils.getDeviceName(this);
+        boolean status = vncStartServer(displayMetrics.widthPixels,
+                displayMetrics.heightPixels,
+                port,
+                name,
+                password,
+                getFilesDir().getAbsolutePath() + File.separator + "novnc");
+
+        Intent answer = new Intent(ACTION_START);
+        answer.putExtra(EXTRA_REQUEST_ID, startIntent.getStringExtra(EXTRA_REQUEST_ID));
+        answer.putExtra(EXTRA_REQUEST_SUCCESS, status);
+        sendBroadcastToOthersAndUs(answer);
+
+        if (status) {
+            MainServicePersistData.saveLastActiveState(this, true);
+            startScreenCapture();
+            registerNSD(name, port);
+            updateNotification();
+            // if we got here, we want to restart if we were killed
+            return START_REDELIVER_INTENT;
+        } else {
+            MainServicePersistData.clear(this);
+            stopSelfByUs();
+            return START_NOT_STICKY;
+        }
+    }
+
     @SuppressLint("WakelockTimeout")
     @SuppressWarnings("unused")
     static void onClientConnected(long client) {

app/src/main/java/net/christianbeier/droidvnc_ng/NotificationRequestActivity.java

@@ -18,7 +18,7 @@ public class NotificationRequestActivity extends AppCompatActivity {
 
     private static final String TAG = "NotificationRequestActivity";
     private static final int REQUEST_POST_NOTIFICATION = 45;
-    private static final String PREFS_KEY_POST_NOTIFICATION_PERMISSION_ASKED_BEFORE = "post_notification_permission_asked_before";
+    public static final String PREFS_KEY_POST_NOTIFICATION_PERMISSION_ASKED_BEFORE = "post_notification_permission_asked_before";
 
 
     @Override

app/src/main/java/net/christianbeier/droidvnc_ng/WriteStorageRequestActivity.java

@@ -38,7 +38,7 @@ public class WriteStorageRequestActivity extends AppCompatActivity {
 
     private static final String TAG = "WriteStorageRequestActivity";
     private static final int REQUEST_WRITE_STORAGE = 44;
-    private static final String PREFS_KEY_PERMISSION_ASKED_BEFORE = "write_storage_permission_asked_before";
+    public static final String PREFS_KEY_PERMISSION_ASKED_BEFORE = "write_storage_permission_asked_before";
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {