src/com/owncloud/android/files/OwnCloudFolderObserver.java

   1 /* ownCloud Android client application
   2  *   Copyright (C) 2012-2014 ownCloud Inc.
   3  *
   4  *   This program is free software: you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License version 2,
   6  *   as published by the Free Software Foundation.
   7  *
   8  *   This program is distributed in the hope that it will be useful,
   9  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  *   GNU General Public License for more details.
  12  *
  13  *   You should have received a copy of the GNU General Public License
  14  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  *
  16  */
  17
  18 package com.owncloud.android.files;
  19
  20 import java.io.File;
  21 import java.util.HashMap;
  22 import java.util.Map;
  23
  24 import android.accounts.Account;
  25 import android.content.Context;
  26 import android.content.Intent;
  27 import android.os.FileObserver;
  28
  29 import com.owncloud.android.datamodel.FileDataStorageManager;
  30 import com.owncloud.android.datamodel.OCFile;
  31 import com.owncloud.android.lib.common.operations.RemoteOperationResult;
  32 import com.owncloud.android.lib.common.operations.RemoteOperationResult.ResultCode;
  33 import com.owncloud.android.operations.SynchronizeFileOperation;
  34 import com.owncloud.android.ui.activity.ConflictsResolveActivity;
  35 import com.owncloud.android.utils.Log_OC;
  36
  37 /**
  38  * Observer watching a folder to request the synchronization of kept-in-sync files
  39  * inside it.
  40  *
  41  * Takes into account two possible update cases:
  42  *  - an editor directly updates the file;
  43  *  - an editor works on a temporal file, and later replaces the kept-in-sync file with the
  44  *  temporal.
  45  *
  46  *  The second case requires to monitor the folder parent of the files, since a direct
  47  *  {@link FileObserver} on it will not receive more events after the file is deleted to
  48  *  be replaced later.
  49  *
  50  * @author David A. Velasco
  51  */
  52 public class OwnCloudFolderObserver extends FileObserver {
  53
  54     private static int UPDATE_MASK = (
  55             FileObserver.ATTRIB | FileObserver.MODIFY |
  56             FileObserver.MOVED_TO | FileObserver.CLOSE_WRITE
  57     );
  58     /*
  59     private static int ALL_EVENTS_EVEN_THOSE_NOT_DOCUMENTED = 0x7fffffff;   // NEVER use 0xffffffff
  60     */
  61
  62     private static String TAG = OwnCloudFolderObserver.class.getSimpleName();
  63
  64     private String mPath;
  65     private Account mAccount;
  66     private Context mContext;
  67     private Map<String, Boolean> mObservedChildren;
  68
  69     public OwnCloudFolderObserver(String path, Account account, Context context) {
  70         super(path, UPDATE_MASK);
  71
  72         if (path == null)
  73             throw new IllegalArgumentException("NULL path argument received");
  74         if (account == null)
  75             throw new IllegalArgumentException("NULL account argument received");
  76         if (context == null)
  77             throw new IllegalArgumentException("NULL context argument received");
  78
  79         mPath = path;
  80         mAccount = account;
  81         mContext = context;
  82         mObservedChildren = new HashMap<String, Boolean>();
  83     }
  84
  85
  86     @Override
  87     public void onEvent(int event, String path) {
  88         Log_OC.d(TAG, "Got event " + event + " on FOLDER " + mPath + " about "
  89                 + ((path != null) ? path : ""));
  90
  91         boolean shouldSynchronize = false;
  92         synchronized(mObservedChildren) {
  93             if (path != null && path.length() > 0 && mObservedChildren.containsKey(path)) {
  94
  95                 if (    ((event & FileObserver.MODIFY) != 0) ||
  96                         ((event & FileObserver.ATTRIB) != 0) ||
  97                         ((event & FileObserver.MOVED_TO) != 0) ) {
  98
  99                     if (mObservedChildren.get(path) != true) {
 100                         mObservedChildren.put(path, Boolean.valueOf(true));
 101                     }
 102                 }
 103
 104                 if ((event & FileObserver.CLOSE_WRITE) != 0) {
 105                     mObservedChildren.put(path, Boolean.valueOf(false));
 106                     shouldSynchronize = true;
 107                 }
 108             }
 109         }
 110         if (shouldSynchronize) {
 111             startSyncOperation(path);
 112         }
 113
 114         if ((event & OwnCloudFileObserver.IN_IGNORE) != 0 &&
 115                 (path == null || path.length() == 0)) {
 116             Log_OC.d(TAG, "Stopping the observance on " + mPath);
 117         }
 118
 119     }
 120
 121
 122     public void startWatching(String localPath) {
 123         synchronized (mObservedChildren) {
 124             if (!mObservedChildren.containsKey(localPath)) {
 125                 mObservedChildren.put(localPath, Boolean.valueOf(false));
 126             }
 127         }
 128
 129         if (new File(mPath).exists()) {
 130             startWatching();
 131             Log_OC.d(TAG, "Started watching parent folder " + mPath + "/");
 132         }
 133         // else - the observance can't be started on a file not existing;
 134     }
 135
 136     public void stopWatching(String localPath) {
 137         synchronized (mObservedChildren) {
 138             mObservedChildren.remove(localPath);
 139             if (mObservedChildren.isEmpty()) {
 140                 stopWatching();
 141                 Log_OC.d(TAG, "Stopped watching parent folder " + mPath + "/");
 142             }
 143         }
 144     }
 145
 146     public boolean isEmpty() {
 147         synchronized (mObservedChildren) {
 148             return mObservedChildren.isEmpty();
 149         }
 150     }
 151
 152
 153     private void startSyncOperation(String childName) {
 154         FileDataStorageManager storageManager =
 155                 new FileDataStorageManager(mAccount, mContext.getContentResolver());
 156         // a fresh object is needed; many things could have occurred to the file
 157         // since it was registered to observe again, assuming that local files
 158         // are linked to a remote file AT MOST, SOMETHING TO BE DONE;
 159         OCFile file = storageManager.getFileByLocalPath(mPath + File.separator + childName);
 160         SynchronizeFileOperation sfo =
 161                 new SynchronizeFileOperation(file, null, mAccount, true, mContext);
 162         RemoteOperationResult result = sfo.execute(storageManager, mContext);
 163         if (result.getCode() == ResultCode.SYNC_CONFLICT) {
 164             // ISSUE 5: if the user is not running the app (this is a service!),
 165             // this can be very intrusive; a notification should be preferred
 166             Intent i = new Intent(mContext, ConflictsResolveActivity.class);
 167             i.setFlags(i.getFlags() | Intent.FLAG_ACTIVITY_NEW_TASK);
 168             i.putExtra(ConflictsResolveActivity.EXTRA_FILE, file);
 169             i.putExtra(ConflictsResolveActivity.EXTRA_ACCOUNT, mAccount);
 170             mContext.startActivity(i);
 171         }
 172         // TODO save other errors in some point where the user can inspect them later;
 173         // or maybe just toast them;
 174         // or nothing, very strange fails
 175     }
 176
 177 }