com.digitalarx.android.files.services.FileDownloader.java Source code

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/* 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.digitalarx.android.files.services;

import java.io.File;
import java.io.IOException;
import java.util.AbstractList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Vector;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import com.digitalarx.android.R;
import com.digitalarx.android.authentication.AuthenticatorActivity;
import com.digitalarx.android.datamodel.FileDataStorageManager;
import com.digitalarx.android.datamodel.OCFile;

import com.owncloud.android.lib.common.network.OnDatatransferProgressListener;
import com.owncloud.android.lib.common.OwnCloudAccount;
import com.owncloud.android.lib.common.OwnCloudClient;
import com.owncloud.android.lib.common.OwnCloudClientManagerFactory;
import com.digitalarx.android.notifications.NotificationBuilderWithProgressBar;
import com.digitalarx.android.notifications.NotificationDelayer;
import com.owncloud.android.lib.common.operations.RemoteOperationResult;
import com.owncloud.android.lib.common.operations.RemoteOperationResult.ResultCode;
import com.owncloud.android.lib.resources.files.FileUtils;
import com.digitalarx.android.operations.DownloadFileOperation;
import com.digitalarx.android.ui.activity.FileActivity;
import com.digitalarx.android.ui.activity.FileDisplayActivity;
import com.digitalarx.android.ui.preview.PreviewImageActivity;
import com.digitalarx.android.ui.preview.PreviewImageFragment;
import com.digitalarx.android.utils.ErrorMessageAdapter;
import com.digitalarx.android.utils.Log_OC;

import android.accounts.Account;
import android.accounts.AccountsException;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.IBinder;
import android.os.Looper;
import android.os.Message;
import android.os.Process;
import android.support.v4.app.NotificationCompat;

public class FileDownloader extends Service implements OnDatatransferProgressListener {

    public static final String EXTRA_ACCOUNT = "ACCOUNT";
    public static final String EXTRA_FILE = "FILE";

    private static final String DOWNLOAD_ADDED_MESSAGE = "DOWNLOAD_ADDED";
    private static final String DOWNLOAD_FINISH_MESSAGE = "DOWNLOAD_FINISH";
    public static final String EXTRA_DOWNLOAD_RESULT = "RESULT";
    public static final String EXTRA_FILE_PATH = "FILE_PATH";
    public static final String EXTRA_REMOTE_PATH = "REMOTE_PATH";
    public static final String ACCOUNT_NAME = "ACCOUNT_NAME";

    private static final String TAG = "FileDownloader";

    private Looper mServiceLooper;
    private ServiceHandler mServiceHandler;
    private IBinder mBinder;
    private OwnCloudClient mDownloadClient = null;
    private Account mLastAccount = null;
    private FileDataStorageManager mStorageManager;

    private ConcurrentMap<String, DownloadFileOperation> mPendingDownloads = new ConcurrentHashMap<String, DownloadFileOperation>();
    private DownloadFileOperation mCurrentDownload = null;

    private NotificationManager mNotificationManager;
    private NotificationCompat.Builder mNotificationBuilder;
    private int mLastPercent;

    public static String getDownloadAddedMessage() {
        return FileDownloader.class.getName().toString() + DOWNLOAD_ADDED_MESSAGE;
    }

    public static String getDownloadFinishMessage() {
        return FileDownloader.class.getName().toString() + DOWNLOAD_FINISH_MESSAGE;
    }

    /**
     * Builds a key for mPendingDownloads from the account and file to download
     * 
     * @param account   Account where the file to download is stored
     * @param file      File to download
     */
    private String buildRemoteName(Account account, OCFile file) {
        return account.name + file.getRemotePath();
    }

    /**
     * Service initialization
     */
    @Override
    public void onCreate() {
        super.onCreate();
        mNotificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
        HandlerThread thread = new HandlerThread("FileDownloaderThread", Process.THREAD_PRIORITY_BACKGROUND);
        thread.start();
        mServiceLooper = thread.getLooper();
        mServiceHandler = new ServiceHandler(mServiceLooper, this);
        mBinder = new FileDownloaderBinder();
    }

    /**
     * Entry point to add one or several files to the queue of downloads.
     * 
     * New downloads are added calling to startService(), resulting in a call to this method. This ensures the service will keep on working 
     * although the caller activity goes away.
     */
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        if (!intent.hasExtra(EXTRA_ACCOUNT) || !intent.hasExtra(EXTRA_FILE)
        /*!intent.hasExtra(EXTRA_FILE_PATH) ||
        !intent.hasExtra(EXTRA_REMOTE_PATH)*/
        ) {
            Log_OC.e(TAG, "Not enough information provided in intent");
            return START_NOT_STICKY;
        }
        Account account = intent.getParcelableExtra(EXTRA_ACCOUNT);
        OCFile file = intent.getParcelableExtra(EXTRA_FILE);

        AbstractList<String> requestedDownloads = new Vector<String>(); // dvelasco: now this always contains just one element, but that can change in a near future (download of multiple selection)
        String downloadKey = buildRemoteName(account, file);
        try {
            DownloadFileOperation newDownload = new DownloadFileOperation(account, file);
            mPendingDownloads.putIfAbsent(downloadKey, newDownload);
            newDownload.addDatatransferProgressListener(this);
            newDownload.addDatatransferProgressListener((FileDownloaderBinder) mBinder);
            requestedDownloads.add(downloadKey);
            sendBroadcastNewDownload(newDownload);

        } catch (IllegalArgumentException e) {
            Log_OC.e(TAG, "Not enough information provided in intent: " + e.getMessage());
            return START_NOT_STICKY;
        }

        if (requestedDownloads.size() > 0) {
            Message msg = mServiceHandler.obtainMessage();
            msg.arg1 = startId;
            msg.obj = requestedDownloads;
            mServiceHandler.sendMessage(msg);
        }

        return START_NOT_STICKY;
    }

    /**
     * Provides a binder object that clients can use to perform operations on the queue of downloads, excepting the addition of new files. 
     * 
     * Implemented to perform cancellation, pause and resume of existing downloads.
     */
    @Override
    public IBinder onBind(Intent arg0) {
        return mBinder;
    }

    /**
     * Called when ALL the bound clients were onbound.
     */
    @Override
    public boolean onUnbind(Intent intent) {
        ((FileDownloaderBinder) mBinder).clearListeners();
        return false; // not accepting rebinding (default behaviour)
    }

    /**
     *  Binder to let client components to perform operations on the queue of downloads.
     * 
     *  It provides by itself the available operations.
     */
    public class FileDownloaderBinder extends Binder implements OnDatatransferProgressListener {

        /** 
         * Map of listeners that will be reported about progress of downloads from a {@link FileDownloaderBinder} instance 
         */
        private Map<String, OnDatatransferProgressListener> mBoundListeners = new HashMap<String, OnDatatransferProgressListener>();

        /**
         * Cancels a pending or current download of a remote file.
         * 
         * @param account       Owncloud account where the remote file is stored.
         * @param file          A file in the queue of pending downloads
         */
        public void cancel(Account account, OCFile file) {
            DownloadFileOperation download = null;
            synchronized (mPendingDownloads) {
                download = mPendingDownloads.remove(buildRemoteName(account, file));
            }
            if (download != null) {
                download.cancel();
            }
        }

        public void clearListeners() {
            mBoundListeners.clear();
        }

        /**
         * Returns True when the file described by 'file' in the ownCloud account 'account' is downloading or waiting to download.
         * 
         * If 'file' is a directory, returns 'true' if some of its descendant files is downloading or waiting to download. 
         * 
         * @param account       Owncloud account where the remote file is stored.
         * @param file          A file that could be in the queue of downloads.
         */
        public boolean isDownloading(Account account, OCFile file) {
            if (account == null || file == null)
                return false;
            String targetKey = buildRemoteName(account, file);
            synchronized (mPendingDownloads) {
                if (file.isFolder()) {
                    // this can be slow if there are many downloads :(
                    Iterator<String> it = mPendingDownloads.keySet().iterator();
                    boolean found = false;
                    while (it.hasNext() && !found) {
                        found = it.next().startsWith(targetKey);
                    }
                    return found;
                } else {
                    return (mPendingDownloads.containsKey(targetKey));
                }
            }
        }

        /**
         * Adds a listener interested in the progress of the download for a concrete file.
         * 
         * @param listener      Object to notify about progress of transfer.    
         * @param account       ownCloud account holding the file of interest.
         * @param file          {@link OCfile} of interest for listener. 
         */
        public void addDatatransferProgressListener(OnDatatransferProgressListener listener, Account account,
                OCFile file) {
            if (account == null || file == null || listener == null)
                return;
            String targetKey = buildRemoteName(account, file);
            mBoundListeners.put(targetKey, listener);
        }

        /**
         * Removes a listener interested in the progress of the download for a concrete file.
         * 
         * @param listener      Object to notify about progress of transfer.    
         * @param account       ownCloud account holding the file of interest.
         * @param file          {@link OCfile} of interest for listener. 
         */
        public void removeDatatransferProgressListener(OnDatatransferProgressListener listener, Account account,
                OCFile file) {
            if (account == null || file == null || listener == null)
                return;
            String targetKey = buildRemoteName(account, file);
            if (mBoundListeners.get(targetKey) == listener) {
                mBoundListeners.remove(targetKey);
            }
        }

        @Override
        public void onTransferProgress(long progressRate, long totalTransferredSoFar, long totalToTransfer,
                String fileName) {
            String key = buildRemoteName(mCurrentDownload.getAccount(), mCurrentDownload.getFile());
            OnDatatransferProgressListener boundListener = mBoundListeners.get(key);
            if (boundListener != null) {
                boundListener.onTransferProgress(progressRate, totalTransferredSoFar, totalToTransfer, fileName);
            }
        }

    }

    /** 
     * Download worker. Performs the pending downloads in the order they were requested. 
     * 
     * Created with the Looper of a new thread, started in {@link FileUploader#onCreate()}. 
     */
    private static class ServiceHandler extends Handler {
        // don't make it a final class, and don't remove the static ; lint will warn about a possible memory leak
        FileDownloader mService;

        public ServiceHandler(Looper looper, FileDownloader service) {
            super(looper);
            if (service == null)
                throw new IllegalArgumentException("Received invalid NULL in parameter 'service'");
            mService = service;
        }

        @Override
        public void handleMessage(Message msg) {
            @SuppressWarnings("unchecked")
            AbstractList<String> requestedDownloads = (AbstractList<String>) msg.obj;
            if (msg.obj != null) {
                Iterator<String> it = requestedDownloads.iterator();
                while (it.hasNext()) {
                    mService.downloadFile(it.next());
                }
            }
            mService.stopSelf(msg.arg1);
        }
    }

    /**
     * Core download method: requests a file to download and stores it.
     * 
     * @param downloadKey   Key to access the download to perform, contained in mPendingDownloads 
     */
    private void downloadFile(String downloadKey) {

        synchronized (mPendingDownloads) {
            mCurrentDownload = mPendingDownloads.get(downloadKey);
        }

        if (mCurrentDownload != null) {

            notifyDownloadStart(mCurrentDownload);

            RemoteOperationResult downloadResult = null;
            try {
                /// prepare client object to send the request to the ownCloud server
                if (mDownloadClient == null || !mLastAccount.equals(mCurrentDownload.getAccount())) {
                    mLastAccount = mCurrentDownload.getAccount();
                    mStorageManager = new FileDataStorageManager(mLastAccount, getContentResolver());
                    OwnCloudAccount ocAccount = new OwnCloudAccount(mLastAccount, this);
                    mDownloadClient = OwnCloudClientManagerFactory.getDefaultSingleton().getClientFor(ocAccount,
                            this);
                }

                /// perform the download
                downloadResult = mCurrentDownload.execute(mDownloadClient);
                if (downloadResult.isSuccess()) {
                    saveDownloadedFile();
                }

            } catch (AccountsException e) {
                Log_OC.e(TAG, "Error while trying to get autorization for " + mLastAccount.name, e);
                downloadResult = new RemoteOperationResult(e);
            } catch (IOException e) {
                Log_OC.e(TAG, "Error while trying to get autorization for " + mLastAccount.name, e);
                downloadResult = new RemoteOperationResult(e);

            } finally {
                synchronized (mPendingDownloads) {
                    mPendingDownloads.remove(downloadKey);
                }
            }

            /// notify result
            notifyDownloadResult(mCurrentDownload, downloadResult);

            sendBroadcastDownloadFinished(mCurrentDownload, downloadResult);
        }
    }

    /**
     * Updates the OC File after a successful download.
     */
    private void saveDownloadedFile() {
        OCFile file = mStorageManager.getFileById(mCurrentDownload.getFile().getFileId());
        long syncDate = System.currentTimeMillis();
        file.setLastSyncDateForProperties(syncDate);
        file.setLastSyncDateForData(syncDate);
        file.setModificationTimestamp(mCurrentDownload.getModificationTimestamp());
        file.setModificationTimestampAtLastSyncForData(mCurrentDownload.getModificationTimestamp());
        // file.setEtag(mCurrentDownload.getEtag());    // TODO Etag, where available
        file.setMimetype(mCurrentDownload.getMimeType());
        file.setStoragePath(mCurrentDownload.getSavePath());
        file.setFileLength((new File(mCurrentDownload.getSavePath()).length()));
        mStorageManager.saveFile(file);
    }

    /**
     * Creates a status notification to show the download progress
     * 
     * @param download  Download operation starting.
     */
    private void notifyDownloadStart(DownloadFileOperation download) {
        /// create status notification with a progress bar
        mLastPercent = 0;
        mNotificationBuilder = NotificationBuilderWithProgressBar.newNotificationBuilderWithProgressBar(this);
        mNotificationBuilder.setSmallIcon(R.drawable.notification_icon)
                .setTicker(getString(R.string.downloader_download_in_progress_ticker))
                .setContentTitle(getString(R.string.downloader_download_in_progress_ticker)).setOngoing(true)
                .setProgress(100, 0, download.getSize() < 0)
                .setContentText(String.format(getString(R.string.downloader_download_in_progress_content), 0,
                        new File(download.getSavePath()).getName()));

        /// includes a pending intent in the notification showing the details view of the file
        Intent showDetailsIntent = null;
        if (PreviewImageFragment.canBePreviewed(download.getFile())) {
            showDetailsIntent = new Intent(this, PreviewImageActivity.class);
        } else {
            showDetailsIntent = new Intent(this, FileDisplayActivity.class);
        }
        showDetailsIntent.putExtra(FileActivity.EXTRA_FILE, download.getFile());
        showDetailsIntent.putExtra(FileActivity.EXTRA_ACCOUNT, download.getAccount());
        showDetailsIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

        mNotificationBuilder.setContentIntent(
                PendingIntent.getActivity(this, (int) System.currentTimeMillis(), showDetailsIntent, 0));

        mNotificationManager.notify(R.string.downloader_download_in_progress_ticker, mNotificationBuilder.build());
    }

    /**
     * Callback method to update the progress bar in the status notification.
     */
    @Override
    public void onTransferProgress(long progressRate, long totalTransferredSoFar, long totalToTransfer,
            String filePath) {
        int percent = (int) (100.0 * ((double) totalTransferredSoFar) / ((double) totalToTransfer));
        if (percent != mLastPercent) {
            mNotificationBuilder.setProgress(100, percent, totalToTransfer < 0);
            String fileName = filePath.substring(filePath.lastIndexOf(FileUtils.PATH_SEPARATOR) + 1);
            String text = String.format(getString(R.string.downloader_download_in_progress_content), percent,
                    fileName);
            mNotificationBuilder.setContentText(text);
            mNotificationManager.notify(R.string.downloader_download_in_progress_ticker,
                    mNotificationBuilder.build());
        }
        mLastPercent = percent;
    }

    /**
     * Updates the status notification with the result of a download operation.
     * 
     * @param downloadResult    Result of the download operation.
     * @param download          Finished download operation
     */
    private void notifyDownloadResult(DownloadFileOperation download, RemoteOperationResult downloadResult) {
        mNotificationManager.cancel(R.string.downloader_download_in_progress_ticker);
        if (!downloadResult.isCancelled()) {
            int tickerId = (downloadResult.isSuccess()) ? R.string.downloader_download_succeeded_ticker
                    : R.string.downloader_download_failed_ticker;

            boolean needsToUpdateCredentials = (downloadResult.getCode() == ResultCode.UNAUTHORIZED
                    || downloadResult.isIdPRedirection());
            tickerId = (needsToUpdateCredentials) ? R.string.downloader_download_failed_credentials_error
                    : tickerId;

            mNotificationBuilder.setTicker(getString(tickerId)).setContentTitle(getString(tickerId))
                    .setAutoCancel(true).setOngoing(false).setProgress(0, 0, false);

            if (needsToUpdateCredentials) {

                // let the user update credentials with one click
                Intent updateAccountCredentials = new Intent(this, AuthenticatorActivity.class);
                updateAccountCredentials.putExtra(AuthenticatorActivity.EXTRA_ACCOUNT, download.getAccount());
                updateAccountCredentials.putExtra(AuthenticatorActivity.EXTRA_ACTION,
                        AuthenticatorActivity.ACTION_UPDATE_EXPIRED_TOKEN);
                updateAccountCredentials.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                updateAccountCredentials.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
                updateAccountCredentials.addFlags(Intent.FLAG_FROM_BACKGROUND);
                mNotificationBuilder.setContentIntent(PendingIntent.getActivity(this,
                        (int) System.currentTimeMillis(), updateAccountCredentials, PendingIntent.FLAG_ONE_SHOT));

                mDownloadClient = null; // grant that future retries on the same account will get the fresh credentials

            } else {
                // TODO put something smart in showDetailsIntent
                Intent showDetailsIntent = new Intent();
                mNotificationBuilder.setContentIntent(
                        PendingIntent.getActivity(this, (int) System.currentTimeMillis(), showDetailsIntent, 0));
            }

            mNotificationBuilder.setContentText(
                    ErrorMessageAdapter.getErrorCauseMessage(downloadResult, download, getResources()));
            mNotificationManager.notify(tickerId, mNotificationBuilder.build());

            // Remove success notification
            if (downloadResult.isSuccess()) {
                // Sleep 2 seconds, so show the notification before remove it
                NotificationDelayer.cancelWithDelay(mNotificationManager,
                        R.string.downloader_download_succeeded_ticker, 2000);
            }

        }
    }

    /**
     * Sends a broadcast when a download finishes in order to the interested activities can update their view
     * 
     * @param download          Finished download operation
     * @param downloadResult    Result of the download operation
     */
    private void sendBroadcastDownloadFinished(DownloadFileOperation download,
            RemoteOperationResult downloadResult) {
        Intent end = new Intent(getDownloadFinishMessage());
        end.putExtra(EXTRA_DOWNLOAD_RESULT, downloadResult.isSuccess());
        end.putExtra(ACCOUNT_NAME, download.getAccount().name);
        end.putExtra(EXTRA_REMOTE_PATH, download.getRemotePath());
        end.putExtra(EXTRA_FILE_PATH, download.getSavePath());
        sendStickyBroadcast(end);
    }

    /**
     * Sends a broadcast when a new download is added to the queue.
     * 
     * @param download          Added download operation
     */
    private void sendBroadcastNewDownload(DownloadFileOperation download) {
        Intent added = new Intent(getDownloadAddedMessage());
        added.putExtra(ACCOUNT_NAME, download.getAccount().name);
        added.putExtra(EXTRA_REMOTE_PATH, download.getRemotePath());
        added.putExtra(EXTRA_FILE_PATH, download.getSavePath());
        sendStickyBroadcast(added);
    }

}