Create observer class for parent folders
[pub/Android/ownCloud.git] / src / com / owncloud / android / files / services / FileObserverService.java
index 25b5f1c..6d0c83e 100644 (file)
+/* ownCloud Android client application
+ *   Copyright (C) 2012 Bartek Przybylski
+ *   Copyright (C) 2012-2013 ownCloud Inc.
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License version 2,
+ *   as published by the Free Software Foundation.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
 package com.owncloud.android.files.services;
 
-import java.util.ArrayList;
-import java.util.List;
+import java.io.File;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
 
-import com.owncloud.android.AccountUtils;
-import com.owncloud.android.datamodel.FileDataStorageManager;
+import com.owncloud.android.MainApp;
+import com.owncloud.android.authentication.AccountUtils;
+import com.owncloud.android.datamodel.OCFile;
 import com.owncloud.android.db.ProviderMeta.ProviderTableMeta;
 import com.owncloud.android.files.OwnCloudFileObserver;
+import com.owncloud.android.files.OwnCloudFolderObserver;
+import com.owncloud.android.operations.SynchronizeFileOperation;
+import com.owncloud.android.utils.FileStorageUtils;
+import com.owncloud.android.utils.Log_OC;
+
 
 import android.accounts.Account;
-import android.accounts.AccountManager;
 import android.app.Service;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.database.Cursor;
-import android.os.Binder;
 import android.os.IBinder;
-import android.util.Log;
 
+/**
+ * Service keeping a list of {@link FileObserver} instances that watch for local
+ * changes in favorite files (formerly known as kept-in-sync files) and try to
+ * synchronize them with the OC server as soon as possible.
+ * 
+ * Tries to be alive as long as possible; that is the reason why stopSelf() is
+ * never called.
+ * 
+ * It is expected that the system eventually kills the service when runs low of
+ * memory. To minimize the impact of this, the service always returns
+ * Service.START_STICKY, and the later restart of the service is explicitly
+ * considered in {@link FileObserverService#onStartCommand(Intent, int, int)}.
+ * 
+ * @author David A. Velasco
+ */
 public class FileObserverService extends Service {
 
-    public final static String KEY_FILE_CMD = "KEY_FILE_CMD";
-    public final static String KEY_CMD_ARG = "KEY_CMD_ARG";
+    public final static String MY_NAME = FileObserverService.class.getCanonicalName();
+    public final static String ACTION_INIT_OBSERVED_LIST = MY_NAME + ".action.INIT_OBSERVED_LIST";
+    public final static String CMD_ADD_OBSERVED_FILE = MY_NAME + ".action.ADD_OBSERVED_FILE";
+    public final static String CMD_DEL_OBSERVED_FILE = MY_NAME + ".action.DEL_OBSERVED_FILE";
+
+    public final static String KEY_CMD_ARG_FILE = "KEY_CMD_ARG_FILE";
+    public final static String KEY_CMD_ARG_ACCOUNT = "KEY_CMD_ARG_ACCOUNT";
+
+    private static String TAG = FileObserverService.class.getSimpleName();
+
+    private static Map<String, OwnCloudFileObserver> mObserversMap;
+    private static Map<String, OwnCloudFolderObserver> mObserversFolderMap;
+    private static DownloadCompletedReceiver mDownloadReceiver;
+
+    /**
+     * Factory method to create intents that allow to start an
+     * ACTION_INIT_OBSERVED_LIST command.
+     * 
+     * @param context Android context of the caller component.
+     * @return Intent that starts a command ACTION_INIT_OBSERVED_LIST when
+     *         {@link Context#startService(Intent)} is called.
+     */
+    public static Intent makeInitIntent(Context context) {
+        Intent i = new Intent(context, FileObserverService.class);
+        i.setAction(ACTION_INIT_OBSERVED_LIST);
+        return i;
+    }
+
+    /**
+     * Factory method to create intents that allow to start or stop the
+     * observance of a file.
+     * 
+     * @param context Android context of the caller component.
+     * @param file OCFile to start or stop to watch.
+     * @param account OC account containing file.
+     * @param watchIt 'True' creates an intent to watch, 'false' an intent to
+     *            stop watching.
+     * @return Intent to start or stop the observance of a file through a call
+     *         to {@link Context#startService(Intent)}.
+     */
+    public static Intent makeObservedFileIntent(Context context, OCFile file, Account account, boolean watchIt) {
+        Intent intent = new Intent(context, FileObserverService.class);
+        intent.setAction(watchIt ? FileObserverService.CMD_ADD_OBSERVED_FILE
+                : FileObserverService.CMD_DEL_OBSERVED_FILE);
+        intent.putExtra(FileObserverService.KEY_CMD_ARG_FILE, file);
+        intent.putExtra(FileObserverService.KEY_CMD_ARG_ACCOUNT, account);
+        return intent;
+    }
+
+    @Override
+    public void onCreate() {
+        Log_OC.d(TAG, "onCreate");
+        super.onCreate();
+
+        mDownloadReceiver = new DownloadCompletedReceiver();
+        IntentFilter filter = new IntentFilter();
+        filter.addAction(FileDownloader.getDownloadAddedMessage());
+        filter.addAction(FileDownloader.getDownloadFinishMessage());
+        registerReceiver(mDownloadReceiver, filter);
+
+        mObserversMap = new HashMap<String, OwnCloudFileObserver>();
+        mObserversFolderMap = new HashMap<String, OwnCloudFolderObserver>();
+    }
 
-    public final static int CMD_INIT_OBSERVED_LIST = 1;
-    public final static int CMD_ADD_OBSERVED_FILE = 2;
-    public final static int CMD_DEL_OBSERVED_FILE = 3;
-    public final static int CMD_ADD_DOWNLOADING_FILE = 4;
+    @Override
+    public void onLowMemory() {
+        Log_OC.d(TAG, "ON LOW MEMORY");
 
-    private static String TAG = "FileObserverService";
-    private static List<OwnCloudFileObserver> mObservers;
-    private static List<DownloadCompletedReceiver> mDownloadReceivers;
-    private static Object mReceiverListLock = new Object();
-    private IBinder mBinder = new LocalBinder();
+    }
 
-    public class LocalBinder extends Binder {
-        FileObserverService getService() {
-            return FileObserverService.this;
+    @Override
+    public void onDestroy() {
+        Log_OC.d(TAG, "onDestroy - FINISHING OBSERVATION");
+
+        unregisterReceiver(mDownloadReceiver);
+
+        Iterator<OwnCloudFileObserver> it = mObserversMap.values().iterator();
+        while (it.hasNext()) {
+            it.next().stopWatching();
         }
+        mObserversMap.clear();
+        mObserversMap = null;
+
+        Iterator<OwnCloudFolderObserver> itOCFolder = mObserversFolderMap.values().iterator();
+        while (itOCFolder.hasNext()) {
+            itOCFolder.next().stopWatching();
+        }
+        mObserversFolderMap.clear();
+        mObserversFolderMap = null;
+
+        super.onDestroy();
     }
-    
+
     @Override
     public IBinder onBind(Intent intent) {
-        return mBinder;
+        // this service cannot be bound
+        return null;
     }
 
     @Override
     public int onStartCommand(Intent intent, int flags, int startId) {
-        // this occurs when system tries to restart
-        // service, so we need to reinitialize observers
-        if (intent == null) {
+        Log_OC.d(TAG, "Starting command " + intent);
+
+        if (intent == null || ACTION_INIT_OBSERVED_LIST.equals(intent.getAction())) {
+            // NULL occurs when system tries to restart the service after its
+            // process
+            // was killed
             initializeObservedList();
             return Service.START_STICKY;
-        }
-            
-        if (!intent.hasExtra(KEY_FILE_CMD)) {
-            Log.e(TAG, "No KEY_FILE_CMD argument given");
-            return Service.START_STICKY;
-        }
 
-        switch (intent.getIntExtra(KEY_FILE_CMD, -1)) {
-            case CMD_INIT_OBSERVED_LIST:
-                initializeObservedList();
-                break;
-            case CMD_ADD_OBSERVED_FILE:
-                addObservedFile(intent.getStringExtra(KEY_CMD_ARG));
-                break;
-            case CMD_DEL_OBSERVED_FILE:
-                removeObservedFile(intent.getStringExtra(KEY_CMD_ARG));
-                break;
-            case CMD_ADD_DOWNLOADING_FILE:
-                addDownloadingFile(intent.getStringExtra(KEY_CMD_ARG));
-                break;
-            default:
-                Log.wtf(TAG, "Incorrect key given");
+        } else if (CMD_ADD_OBSERVED_FILE.equals(intent.getAction())) {
+            OCFile file = (OCFile) intent.getParcelableExtra(KEY_CMD_ARG_FILE);
+            Account account = (Account) intent.getParcelableExtra(KEY_CMD_ARG_ACCOUNT);
+            addObservedFile(file, account);
+
+            String localPath = file.getStoragePath();
+            if (localPath == null || localPath.length() <= 0) {
+                // file downloading or to be downloaded for the first time
+                localPath = FileStorageUtils.getDefaultSavePathFor(account.name, file);
+            }
+
+            String parentPath = (new File(localPath)).getParent();
+
+            addObservedFolder(parentPath, account);
+
+        } else if (CMD_DEL_OBSERVED_FILE.equals(intent.getAction())) {
+            removeObservedFile((OCFile) intent.getParcelableExtra(KEY_CMD_ARG_FILE),
+                    (Account) intent.getParcelableExtra(KEY_CMD_ARG_ACCOUNT));
+
+        } else {
+            Log_OC.e(TAG, "Unknown action recieved; ignoring it: " + intent.getAction());
         }
 
         return Service.START_STICKY;
     }
 
+    /**
+     * Read from the local database the list of files that must to be kept
+     * synchronized and starts file observers to monitor local changes on them
+     */
     private void initializeObservedList() {
-        if (mObservers != null) return; // nothing to do here
-        mObservers = new ArrayList<OwnCloudFileObserver>();
-        mDownloadReceivers = new ArrayList<DownloadCompletedReceiver>();
-        Cursor c = getContentResolver().query(
-                ProviderTableMeta.CONTENT_URI,
-                null,
-                ProviderTableMeta.FILE_KEEP_IN_SYNC + " = ?",
-                new String[] {String.valueOf(1)},
-                null);
-        if (!c.moveToFirst()) return;
-        AccountManager acm = AccountManager.get(this);
-        Account[] accounts = acm.getAccounts();
-        do {
-            Account account = null;
-            for (Account a : accounts)
-                if (a.name.equals(c.getString(c.getColumnIndex(ProviderTableMeta.FILE_ACCOUNT_OWNER)))) {
-                    account = a;
-                    break;
-                }
+        Log_OC.d(TAG, "Loading all kept-in-sync files from database to start watching them");
 
-            if (account == null) continue;
-            FileDataStorageManager storage =
-                    new FileDataStorageManager(account, getContentResolver());
-            if (!storage.fileExists(c.getString(c.getColumnIndex(ProviderTableMeta.FILE_PATH))))
-                continue;
-
-            String path = c.getString(c.getColumnIndex(ProviderTableMeta.FILE_STORAGE_PATH));
-            OwnCloudFileObserver observer =
-                    new OwnCloudFileObserver(path, OwnCloudFileObserver.CHANGES_ONLY);
-            observer.setContext(getApplicationContext());
-            observer.setAccount(account);
-            observer.setStorageManager(storage);
-            observer.setOCFile(storage.getFileByPath(c.getString(c.getColumnIndex(ProviderTableMeta.FILE_PATH))));
-            observer.startWatching();
-            mObservers.add(observer);
-            Log.d(TAG, "Started watching file " + path);
-            
-        } while (c.moveToNext());
-        c.close();
-    }
-    
-    private void addObservedFile(String path) {
-        if (path == null) return;
-        if (mObservers == null) {
-            // this is very rare case when service was killed by system
-            // and observers list was deleted in that procedure
-            initializeObservedList();
-        }
-        boolean duplicate = false;
-        OwnCloudFileObserver observer = null;
-        for (int i = 0; i < mObservers.size(); ++i) {
-            observer = mObservers.get(i);
-            if (observer.getPath().equals(path))
-                duplicate = true;
-            observer.setContext(getBaseContext());
+        // mObserversMap.clear();
+        // mObserverParentsMap.clear();
+
+        Cursor cursorOnKeptInSync = getContentResolver().query(ProviderTableMeta.CONTENT_URI, null,
+                ProviderTableMeta.FILE_KEEP_IN_SYNC + " = ?", new String[] { String.valueOf(1) }, null);
+
+        if (cursorOnKeptInSync != null) {
+
+            if (cursorOnKeptInSync.moveToFirst()) {
+
+                String localPath = "";
+                // String remotePath = "";
+                String accountName = "";
+                Account account = null;
+                do {
+                    localPath = cursorOnKeptInSync.getString(cursorOnKeptInSync
+                            .getColumnIndex(ProviderTableMeta.FILE_STORAGE_PATH));
+                    accountName = cursorOnKeptInSync.getString(cursorOnKeptInSync
+                            .getColumnIndex(ProviderTableMeta.FILE_ACCOUNT_OWNER));
+                    /*
+                     * remotePath = cursorOnKeptInSync.getString(
+                     * cursorOnKeptInSync
+                     * .getColumnIndex(ProviderTableMeta.FILE_PATH) );
+                     */
+
+                    account = new Account(accountName, MainApp.getAccountType());
+                    if (!AccountUtils.exists(account, this) || localPath == null || localPath.length() <= 0) {
+                        continue;
+                    }
+
+                    OwnCloudFileObserver observer = mObserversMap.get(localPath);
+                    if (observer == null) {
+                        observer = new OwnCloudFileObserver(localPath, account, getApplicationContext(), mHandler);
+                        mObserversMap.put(localPath, observer);
+
+                        // only if being added
+                        if (new File(localPath).exists()) {
+                            observer.startWatching();
+                            Log_OC.d(TAG, "Started watching file " + localPath);
+                        }
+                    }
+
+                    String parentPath = (new File(localPath)).getParent();
+                    OwnCloudFolderObserver observerFolder = mObserversFolderMap.get(parentPath);
+                    if (observerFolder == null) {
+                        observerFolder = new OwnCloudFolderObserver(parentPath, account, getApplicationContext());
+                        mObserversFolderMap.put(parentPath, observerFolder);
+
+                        if (new File(parentPath).exists()) {
+                            observerFolder.startWatching();
+                            Log_OC.d(TAG, "Started watching parent folder " + parentPath + "/");
+                        }
+                    }
+
+                } while (cursorOnKeptInSync.moveToNext());
+
+            }
+            cursorOnKeptInSync.close();
         }
-        if (duplicate) return;
-        observer = new OwnCloudFileObserver(path, OwnCloudFileObserver.CHANGES_ONLY);
-        observer.setContext(getBaseContext());
-        Account account = AccountUtils.getCurrentOwnCloudAccount(getBaseContext());
-        observer.setAccount(account);
-        FileDataStorageManager storage =
-                new FileDataStorageManager(account, getContentResolver());
-        observer.setStorageManager(storage);
-        observer.setOCFile(storage.getFileByLocalPath(path));
-
-        DownloadCompletedReceiver receiver = new DownloadCompletedReceiver(path, observer);
-        registerReceiver(receiver, new IntentFilter(FileDownloader.DOWNLOAD_FINISH_MESSAGE));
-
-        mObservers.add(observer);
-        Log.d(TAG, "Observer added for path " + path);
+
+        // service does not stopSelf() ; that way it tries to be alive forever
+
     }
-    
-    private void removeObservedFile(String path) {
-        if (path == null) return;
-        if (mObservers == null) {
-            initializeObservedList();
+
+    /**
+     * Registers the local copy of a remote file to be observed for local
+     * changes, an automatically updated in the ownCloud server.
+     * 
+     * This method does NOT perform a {@link SynchronizeFileOperation} over the
+     * file.
+     * 
+     * @param file Object representing a remote file which local copy must be
+     *            observed.
+     * @param account OwnCloud account containing file.
+     */
+    private void addObservedFile(OCFile file, Account account) {
+        Log_OC.v(TAG, "Adding a file to be watched");
+
+        if (file == null) {
+            Log_OC.e(TAG, "Trying to add a NULL file to observer");
             return;
         }
-        for (int i = 0; i < mObservers.size(); ++i) {
-            OwnCloudFileObserver observer = mObservers.get(i);
-            if (observer.getPath().equals(path)) {
-                observer.stopWatching();
-                mObservers.remove(i);
-                break;
+        if (account == null) {
+            Log_OC.e(TAG, "Trying to add a file with a NULL account to observer");
+            return;
+        }
+
+        String localPath = file.getStoragePath();
+        if (localPath == null || localPath.length() <= 0) {
+            // file downloading or to be downloaded for the first time
+            localPath = FileStorageUtils.getDefaultSavePathFor(account.name, file);
+        }
+        OwnCloudFileObserver observer = mObserversMap.get(localPath);
+        if (observer == null) {
+            // / the local file was never registered to observe before
+            observer = new OwnCloudFileObserver(localPath, account, getApplicationContext(), mHandler);
+            mObserversMap.put(localPath, observer);
+            Log_OC.d(TAG, "Observer added for path " + localPath);
+
+            if (file.isDown()) {
+                observer.startWatching();
+                Log_OC.d(TAG, "Started watching " + localPath);
             }
+            // else - the observance can't be started on a file not already
+            // down;
+            // mDownloadReceiver will get noticed when the download of the file
+            // finishes
         }
-        Log.d(TAG, "Stopped watching " + path);
     }
-        
-    private void addDownloadingFile(String remotePath) {
-        OwnCloudFileObserver observer = null;
-        for (OwnCloudFileObserver o : mObservers) {
-            if (o.getRemotePath().equals(remotePath)) {
-                observer = o;
-                break;
+
+    /**
+     * Registers the folder to be observed in which there are changes inside any
+     * file
+     * 
+     * @param localPath String representing the folder will be observed
+     * @param account OwnCloud account containing file.
+     */
+    public void addObservedFolder(String localPath, Account account) {
+        Log_OC.v(TAG, "Adding a child file to be watched");
+
+        String parentPath = (new File(localPath)).getParent();
+        OwnCloudFolderObserver observerParent = mObserversFolderMap.get(parentPath);
+        if (observerParent == null) {
+            observerParent = new OwnCloudFolderObserver(parentPath, account, getApplicationContext());
+            mObserversFolderMap.put(parentPath, observerParent);
+            Log_OC.d(TAG, "Observer added for parent folder " + parentPath + "/");
+
+            if (new File(parentPath).exists()) {
+                observerParent.startWatching();
+                Log_OC.d(TAG, "Started watching parent folder " + parentPath + "/");
             }
         }
-        if (observer == null) {
-            Log.e(TAG, "Couldn't find observer for remote file " + remotePath);
+    }
+
+    /**
+     * Unregisters the local copy of a remote file to be observed for local
+     * changes.
+     * 
+     * Starts to watch it, if the file has a local copy to watch.
+     * 
+     * @param file Object representing a remote file which local copy must be
+     *            not observed longer.
+     * @param account OwnCloud account containing file.
+     */
+    private void removeObservedFile(OCFile file, Account account) {
+        Log_OC.v(TAG, "Removing a file from being watched");
+
+        if (file == null) {
+            Log_OC.e(TAG, "Trying to remove a NULL file");
+            return;
+        }
+        if (account == null) {
+            Log_OC.e(TAG, "Trying to add a file with a NULL account to observer");
             return;
         }
-        observer.stopWatching();
-        DownloadCompletedReceiver dcr = new DownloadCompletedReceiver(observer.getPath(), observer);
-        registerReceiver(dcr, new IntentFilter(FileDownloader.DOWNLOAD_FINISH_MESSAGE));
-    }
 
-    
-    private static void addReceiverToList(DownloadCompletedReceiver r) {
-        synchronized(mReceiverListLock) {
-            mDownloadReceivers.add(r);
+        String localPath = file.getStoragePath();
+        if (localPath == null || localPath.length() <= 0) {
+            localPath = FileStorageUtils.getDefaultSavePathFor(account.name, file);
         }
-    }
-    
-    private static void removeReceiverFromList(DownloadCompletedReceiver r) {
-        synchronized(mReceiverListLock) {
-            mDownloadReceivers.remove(r);
+
+        OwnCloudFileObserver observer = mObserversMap.get(localPath);
+        if (observer != null) {
+            observer.stopWatching();
+            mObserversMap.remove(observer);
+            Log_OC.d(TAG, "Stopped watching " + localPath);
+
+        } else {
+            Log_OC.d(TAG, "No observer to remove for path " + localPath);
         }
+
     }
-    
+
+    /**
+     * Private receiver listening to events broadcast by the FileDownloader
+     * service.
+     * 
+     * Starts and stops the observance on registered files when they are being
+     * download, in order to avoid to start unnecessary synchronizations.
+     */
     private class DownloadCompletedReceiver extends BroadcastReceiver {
-        String mPath;
-        OwnCloudFileObserver mObserver;
-        
-        public DownloadCompletedReceiver(String path, OwnCloudFileObserver observer) {
-            mPath = path;
-            mObserver = observer;
-            addReceiverToList(this);
-        }
-        
+
         @Override
         public void onReceive(Context context, Intent intent) {
-            if (mPath.equals(intent.getStringExtra(FileDownloader.EXTRA_FILE_PATH))) {
-                context.unregisterReceiver(this);
-                removeReceiverFromList(this);
-                mObserver.startWatching();
-                Log.d(TAG, "Started watching " + mPath);
-                return;
+            Log_OC.d(TAG, "Received broadcast intent " + intent);
+
+            String downloadPath = intent.getStringExtra(FileDownloader.EXTRA_FILE_PATH);
+            OwnCloudFileObserver observer = mObserversMap.get(downloadPath);
+            if (observer != null) {
+                if (intent.getAction().equals(FileDownloader.getDownloadFinishMessage())
+                        && new File(downloadPath).exists()) {
+                    // no matter is the download was be successful or not; the
+                    // file could be down,
+                    // anyway due to a former download or upload
+                    observer.startWatching();
+                    Log_OC.d(TAG, "Resuming observance of " + downloadPath);
+
+                } else if (intent.getAction().equals(FileDownloader.getDownloadAddedMessage())) {
+                    observer.stopWatching();
+                    Log_OC.d(TAG, "Pausing observance of " + downloadPath);
+                }
+
+            } else {
+                Log_OC.d(TAG, "No observer for path " + downloadPath);
             }
         }
-        
-        @Override
-        public boolean equals(Object o) {
-            if (o instanceof DownloadCompletedReceiver)
-                return mPath.equals(((DownloadCompletedReceiver)o).mPath);
-            return super.equals(o);
-        }
+
     }
+
 }