/**
 *   ownCloud Android client application
 *
 *   @author David A. Velasco
 *   Copyright (C) 2016 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.operations;

import android.accounts.Account;
import android.content.Context;
import android.net.Uri;

import com.owncloud.android.datamodel.FileDataStorageManager;
import com.owncloud.android.datamodel.OCFile;
import com.owncloud.android.datamodel.ThumbnailsCacheManager;
import com.owncloud.android.db.OCUpload;
import com.owncloud.android.db.PreferenceManager;
import com.owncloud.android.files.services.FileUploader;
import com.owncloud.android.lib.common.OwnCloudClient;
import com.owncloud.android.lib.common.network.OnDatatransferProgressListener;
import com.owncloud.android.lib.common.network.ProgressiveDataTransferer;
import com.owncloud.android.lib.common.operations.OperationCancelledException;
import com.owncloud.android.lib.common.operations.RemoteOperation;
import com.owncloud.android.lib.common.operations.RemoteOperationResult;
import com.owncloud.android.lib.common.operations.RemoteOperationResult.ResultCode;
import com.owncloud.android.lib.common.utils.Log_OC;
import com.owncloud.android.lib.resources.files.ChunkedUploadRemoteFileOperation;
import com.owncloud.android.lib.resources.files.ExistenceCheckRemoteOperation;
import com.owncloud.android.lib.resources.files.ReadRemoteFileOperation;
import com.owncloud.android.lib.resources.files.RemoteFile;
import com.owncloud.android.lib.resources.files.UploadRemoteFileOperation;
import com.owncloud.android.operations.common.SyncOperation;
import com.owncloud.android.utils.ConnectivityUtils;
import com.owncloud.android.utils.FileStorageUtils;
import com.owncloud.android.utils.MimeType;
import com.owncloud.android.utils.MimetypeIconUtil;
import com.owncloud.android.utils.UriUtils;

import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.methods.RequestEntity;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.channels.FileChannel;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import java.util.concurrent.atomic.AtomicBoolean;


/**
 * Operation performing the update in the ownCloud server
 * of a file that was modified locally.
 */
public class UploadFileOperation extends SyncOperation {

    public static final int CREATED_BY_USER = 0;
    public static final int CREATED_AS_INSTANT_PICTURE = 1;
    public static final int CREATED_AS_INSTANT_VIDEO = 2;

    public static OCFile obtainNewOCFileToUpload(String remotePath, String localPath, String mimeType) {

        // MIME type
        if (mimeType == null || mimeType.length() <= 0) {
            mimeType = MimetypeIconUtil.getBestMimeTypeByFilename(localPath);
        }

        OCFile newFile = new OCFile(remotePath);
        newFile.setStoragePath(localPath);
        newFile.setLastSyncDateForProperties(0);
        newFile.setLastSyncDateForData(0);

        // size
        if (localPath != null && localPath.length() > 0) {
            File localFile = new File(localPath);
            newFile.setFileLength(localFile.length());
            newFile.setLastSyncDateForData(localFile.lastModified());
        } // don't worry about not assigning size, the problems with localPath
        // are checked when the UploadFileOperation instance is created


        newFile.setMimetype(mimeType);

        return newFile;
    }

    private static final String TAG = UploadFileOperation.class.getSimpleName();

    private Account mAccount;
    /**
     * OCFile which is to be uploaded.
     */
    private OCFile mFile;
    /**
     * Original OCFile which is to be uploaded in case file had to be renamed
     * (if forceOverwrite==false and remote file already exists).
     */
    private OCFile mOldFile;
    private String mRemotePath = null;
    private boolean mChunked = false;
    private boolean mRemoteFolderToBeCreated = false;
    private boolean mForceOverwrite = false;
    private int mLocalBehaviour = FileUploader.LOCAL_BEHAVIOUR_COPY;
    private int mCreatedBy = CREATED_BY_USER;

    private boolean mWasRenamed = false;
    private long mOCUploadId = -1;
    /**
     * Local path to file which is to be uploaded (before any possible renaming or moving).
     */
    private String mOriginalStoragePath = null;
    private Set<OnDatatransferProgressListener> mDataTransferListeners = new HashSet<OnDatatransferProgressListener>();
    private OnRenameListener mRenameUploadListener;

    private final AtomicBoolean mCancellationRequested = new AtomicBoolean(false);
    private final AtomicBoolean mUploadStarted = new AtomicBoolean(false);

    private Context mContext;

    private UploadRemoteFileOperation mUploadOperation;

    protected RequestEntity mEntity = null;

    public UploadFileOperation(Account account,
                               OCFile file,
                               OCUpload upload,
                               boolean chunked,
                               boolean forceOverwrite,
                               int localBehaviour,
                               Context context
    ) {
        if (account == null)
            throw new IllegalArgumentException("Illegal NULL account in UploadFileOperation " +
                    "creation");
        if (upload == null)
            throw new IllegalArgumentException("Illegal NULL file in UploadFileOperation creation");
        if (upload.getLocalPath() == null || upload.getLocalPath().length() <= 0) {
            throw new IllegalArgumentException(
                    "Illegal file in UploadFileOperation; storage path invalid: "
                            + upload.getLocalPath());
        }

        mAccount = account;
        if (file == null) {
            mFile = obtainNewOCFileToUpload(
                    upload.getRemotePath(),
                    upload.getLocalPath(),
                    upload.getMimeType()
            );
        } else {
            mFile = file;
        }
        mRemotePath = upload.getRemotePath();
        mChunked = chunked;
        mForceOverwrite = forceOverwrite;
        mLocalBehaviour = localBehaviour;
        mOriginalStoragePath = mFile.getStoragePath();
        mContext = context;
        mOCUploadId = upload.getUploadId();
        mCreatedBy = upload.getCreadtedBy();
        mRemoteFolderToBeCreated = upload.isCreateRemoteFolder();
    }

    public Account getAccount() {
        return mAccount;
    }

    public String getFileName() {
        return (mFile != null) ? mFile.getFileName() : null;
    }

    public OCFile getFile() {
        return mFile;
    }

    /**
     * If remote file was renamed, return original OCFile which was uploaded. Is
     * null is file was not renamed.
     */
    public OCFile getOldFile() {
        return mOldFile;
    }

    public String getOriginalStoragePath() {
        return mOriginalStoragePath;
    }

    public String getStoragePath() {
        return mFile.getStoragePath();
    }

    public String getRemotePath() {
        return mFile.getRemotePath();
    }

    public String getMimeType() {
        return mFile.getMimetype();
    }

    public int getLocalBehaviour() {
        return mLocalBehaviour;
    }

    public void setRemoteFolderToBeCreated() {
        mRemoteFolderToBeCreated = true;
    }

    public boolean wasRenamed() {
        return mWasRenamed;
    }

    public void setCreatedBy(int createdBy) {
        mCreatedBy = createdBy;
        if (createdBy < CREATED_BY_USER || CREATED_AS_INSTANT_VIDEO < createdBy) {
            mCreatedBy = CREATED_BY_USER;
        }
    }

    public int getCreatedBy () {
        return mCreatedBy;
    }

    public boolean isInstantPicture() {
        return mCreatedBy == CREATED_AS_INSTANT_PICTURE;
    }

    public boolean isInstantVideo() {
        return mCreatedBy == CREATED_AS_INSTANT_VIDEO;
    }

    public void setOCUploadId(long id){
        mOCUploadId = id;
    }
    public long getOCUploadId() {
        return mOCUploadId;
    }

    public Set<OnDatatransferProgressListener> getDataTransferListeners() {
        return mDataTransferListeners;
    }

    public void addDatatransferProgressListener (OnDatatransferProgressListener listener) {
        synchronized (mDataTransferListeners) {
            mDataTransferListeners.add(listener);
        }
        if (mEntity != null) {
            ((ProgressiveDataTransferer)mEntity).addDatatransferProgressListener(listener);
        }
        if(mUploadOperation != null){
            mUploadOperation.addDatatransferProgressListener(listener);
        }
    }

    public void removeDatatransferProgressListener(OnDatatransferProgressListener listener) {
        synchronized (mDataTransferListeners) {
            mDataTransferListeners.remove(listener);
        }
        if (mEntity != null) {
            ((ProgressiveDataTransferer)mEntity).removeDatatransferProgressListener(listener);
        }
        if(mUploadOperation != null){
            mUploadOperation.removeDatatransferProgressListener(listener);
        }
    }

    public void addRenameUploadListener (OnRenameListener listener) {
        mRenameUploadListener = listener;
    }

    @Override
    protected RemoteOperationResult run(OwnCloudClient client) {
        mCancellationRequested.set(false);
        mUploadStarted.set(true);
        RemoteOperationResult result = null;
        File temporalFile = null, originalFile = new File(mOriginalStoragePath), expectedFile = null;

        try {

            /// Check that connectivity conditions are met and delays the upload otherwise
            if (delayForWifi()) {
                Log_OC.d(TAG, "Upload delayed until WiFi is available: " + getRemotePath());
                return new RemoteOperationResult(ResultCode.DELAYED_FOR_WIFI);
            }

            /// check if the file continues existing before schedule the operation
            if (!originalFile.exists()) {
                Log_OC.d(TAG, mOriginalStoragePath.toString() + " not exists anymore");
                return new RemoteOperationResult(ResultCode.LOCAL_FILE_NOT_FOUND);
            }

            /// check the existence of the parent folder for the file to upload
            String remoteParentPath = new File(getRemotePath()).getParent();
            remoteParentPath = remoteParentPath.endsWith(OCFile.PATH_SEPARATOR) ?
                    remoteParentPath : remoteParentPath + OCFile.PATH_SEPARATOR;
            result = grantFolderExistence(remoteParentPath, client);
            if (!result.isSuccess()) {

                return result;
            }

            /// set parent local id in uploading file
            OCFile parent = getStorageManager().getFileByPath(remoteParentPath);
            mFile.setParentId(parent.getFileId());

            /// automatic rename of file to upload in case of name collision in server
            Log_OC.d(TAG, "Checking name collision in server");
            if (!mForceOverwrite) {
                String remotePath = getAvailableRemotePath(client, mRemotePath);
                mWasRenamed = !remotePath.equals(mRemotePath);
                if (mWasRenamed) {
                    createNewOCFile(remotePath);
                    Log_OC.d(TAG, "File renamed as " + remotePath);
                }
                mRemotePath = remotePath;
                mRenameUploadListener.onRenameUpload();
            }

            if (mCancellationRequested.get()) {
                throw new OperationCancelledException();
            }

            String expectedPath = FileStorageUtils.getDefaultSavePathFor(mAccount.name, mFile);
            expectedFile = new File(expectedPath);

            /// copy the file locally before uploading
            if (mLocalBehaviour == FileUploader.LOCAL_BEHAVIOUR_COPY &&
                    !mOriginalStoragePath.equals(expectedPath)) {

                String temporalPath = FileStorageUtils.getTemporalPath(mAccount.name) + mFile.getRemotePath();
                mFile.setStoragePath(temporalPath);
                temporalFile = new File(temporalPath);

                result = copy(originalFile, temporalFile);
                if (result != null) {
                    return result;
                }
            }

            if (mCancellationRequested.get()) {
                throw new OperationCancelledException();
            }

            /// perform the upload
            if ( mChunked &&
                    (new File(mFile.getStoragePath())).length() >
                            ChunkedUploadRemoteFileOperation.CHUNK_SIZE ) {
                mUploadOperation = new ChunkedUploadRemoteFileOperation(mFile.getStoragePath(),
                        mFile.getRemotePath(), mFile.getMimetype(), mFile.getEtagInConflict());
            } else {
                mUploadOperation = new UploadRemoteFileOperation(mFile.getStoragePath(),
                        mFile.getRemotePath(), mFile.getMimetype(), mFile.getEtagInConflict());
            }
            Iterator <OnDatatransferProgressListener> listener = mDataTransferListeners.iterator();
            while (listener.hasNext()) {
                mUploadOperation.addDatatransferProgressListener(listener.next());
            }

            if (mCancellationRequested.get()) {
                throw new OperationCancelledException();
            }

            result = mUploadOperation.execute(client);

            /// move local temporal file or original file to its corresponding
            // location in the ownCloud local folder
            if (result.isSuccess()) {
                if (mLocalBehaviour == FileUploader.LOCAL_BEHAVIOUR_FORGET) {
                    String temporalPath = FileStorageUtils.getTemporalPath(mAccount.name) + mFile.getRemotePath();
                    if (mOriginalStoragePath.equals(temporalPath)) {
                        // delete local file is was pre-copied in temporary folder (see .ui.helpers.UriUploader)
                        temporalFile = new File(temporalPath);
                        temporalFile.delete();
                    }
                    mFile.setStoragePath("");

                } else {
                    mFile.setStoragePath(expectedPath);

                    if (temporalFile != null) {         // FileUploader.LOCAL_BEHAVIOUR_COPY
                        move(temporalFile, expectedFile);
                    } else {                            // FileUploader.LOCAL_BEHAVIOUR_MOVE
                        move(originalFile, expectedFile);
                        getStorageManager().deleteFileInMediaScan(originalFile.getAbsolutePath());
                    }
                    FileDataStorageManager.triggerMediaScan(expectedFile.getAbsolutePath());
                }

            } else if (result.getHttpCode() == HttpStatus.SC_PRECONDITION_FAILED ) {
                result = new RemoteOperationResult(ResultCode.SYNC_CONFLICT);
            }

        } catch (Exception e) {
            result = new RemoteOperationResult(e);

        } finally {
            mUploadStarted.set(false);
            if (temporalFile != null && !originalFile.equals(temporalFile)) {
                temporalFile.delete();
            }
            if (result == null){
                result = new RemoteOperationResult(ResultCode.UNKNOWN_ERROR);
            }
            if (result.isSuccess()) {
                Log_OC.i(TAG, "Upload of " + mOriginalStoragePath + " to " + mRemotePath + ": " +
                        result.getLogMessage());
            } else {
                if (result.getException() != null) {
                    if(result.isCancelled()){
                        Log_OC.w(TAG, "Upload of " + mOriginalStoragePath + " to " + mRemotePath +
                                ": " + result.getLogMessage());
                    } else {
                        Log_OC.e(TAG, "Upload of " + mOriginalStoragePath + " to " + mRemotePath +
                                ": " + result.getLogMessage(), result.getException());
                    }

                } else {
                    Log_OC.e(TAG, "Upload of " + mOriginalStoragePath + " to " + mRemotePath +
                            ": " + result.getLogMessage());
                }
            }
        }

        if (result.isSuccess()) {
            saveUploadedFile(client);

        } else if (result.getCode() == ResultCode.SYNC_CONFLICT) {
            getStorageManager().saveConflict(mFile, mFile.getEtagInConflict());
        }

        return result;
    }


    /**
     * Checks origin of current upload and network type to decide if should be delayed, according to
     * current user preferences.
     *
     * @return      'True' if the upload was delayed until WiFi connectivity is available, 'false' otherwise.
     */
    private boolean delayForWifi() {
        boolean delayInstantPicture = (
            isInstantPicture() &&  PreferenceManager.instantPictureUploadViaWiFiOnly(mContext)
        );
        boolean delayInstantVideo = (
            isInstantVideo() && PreferenceManager.instantVideoUploadViaWiFiOnly(mContext)
        );
        return (
            (delayInstantPicture || delayInstantVideo) &&
            !ConnectivityUtils.isAppConnectedViaUnmeteredWiFi(mContext)
        );
    }


    /**
     * Checks the existence of the folder where the current file will be uploaded both
     * in the remote server and in the local database.
     * <p/>
     * If the upload is set to enforce the creation of the folder, the method tries to
     * create it both remote and locally.
     *
     * @param pathToGrant Full remote path whose existence will be granted.
     * @return An {@link OCFile} instance corresponding to the folder where the file
     * will be uploaded.
     */
    private RemoteOperationResult grantFolderExistence(String pathToGrant, OwnCloudClient client) {
        RemoteOperation operation = new ExistenceCheckRemoteOperation(pathToGrant, mContext, false);
        RemoteOperationResult result = operation.execute(client);
        if (!result.isSuccess() && result.getCode() == ResultCode.FILE_NOT_FOUND && mRemoteFolderToBeCreated) {
            SyncOperation syncOp = new CreateFolderOperation(pathToGrant, true);
            result = syncOp.execute(client, getStorageManager());
        }
        if (result.isSuccess()) {
            OCFile parentDir = getStorageManager().getFileByPath(pathToGrant);
            if (parentDir == null) {
                parentDir = createLocalFolder(pathToGrant);
            }
            if (parentDir != null) {
                result = new RemoteOperationResult(ResultCode.OK);
            } else {
                result = new RemoteOperationResult(ResultCode.UNKNOWN_ERROR);
            }
        }
        return result;
    }

    private OCFile createLocalFolder(String remotePath) {
        String parentPath = new File(remotePath).getParent();
        parentPath = parentPath.endsWith(OCFile.PATH_SEPARATOR) ?
                parentPath : parentPath + OCFile.PATH_SEPARATOR;
        OCFile parent = getStorageManager().getFileByPath(parentPath);
        if (parent == null) {
            parent = createLocalFolder(parentPath);
        }
        if (parent != null) {
            OCFile createdFolder = new OCFile(remotePath);
            createdFolder.setMimetype(MimeType.DIRECTORY);
            createdFolder.setParentId(parent.getFileId());
            getStorageManager().saveFile(createdFolder);
            return createdFolder;
        }
        return null;
    }


    /**
     * Create a new OCFile mFile with new remote path. This is required if forceOverwrite==false.
     * New file is stored as mFile, original as mOldFile. 
     * @param newRemotePath new remote path
     */
    private void createNewOCFile(String newRemotePath) {
        // a new OCFile instance must be created for a new remote path
        OCFile newFile = new OCFile(newRemotePath);
        newFile.setCreationTimestamp(mFile.getCreationTimestamp());
        newFile.setFileLength(mFile.getFileLength());
        newFile.setMimetype(mFile.getMimetype());
        newFile.setModificationTimestamp(mFile.getModificationTimestamp());
        newFile.setModificationTimestampAtLastSyncForData(
                mFile.getModificationTimestampAtLastSyncForData()
        );
        newFile.setEtag(mFile.getEtag());
        newFile.setFavorite(mFile.isFavorite());
        newFile.setLastSyncDateForProperties(mFile.getLastSyncDateForProperties());
        newFile.setLastSyncDateForData(mFile.getLastSyncDateForData());
        newFile.setStoragePath(mFile.getStoragePath());
        newFile.setParentId(mFile.getParentId());
        mOldFile = mFile;
        mFile = newFile;
    }

    /**
     * Checks if remotePath does not exist in the server and returns it, or adds
     * a suffix to it in order to avoid the server file is overwritten.
     *
     * @param wc
     * @param remotePath
     * @return
     */
    private String getAvailableRemotePath(OwnCloudClient wc, String remotePath) {
        boolean check = existsFile(wc, remotePath);
        if (!check) {
            return remotePath;
        }

        int pos = remotePath.lastIndexOf(".");
        String suffix = "";
        String extension = "";
        if (pos >= 0) {
            extension = remotePath.substring(pos + 1);
            remotePath = remotePath.substring(0, pos);
        }
        int count = 2;
        do {
            suffix = " (" + count + ")";
            if (pos >= 0) {
                check = existsFile(wc, remotePath + suffix + "." + extension);
            }
            else {
                check = existsFile(wc, remotePath + suffix);
            }
            count++;
        } while (check);

        if (pos >= 0) {
            return remotePath + suffix + "." + extension;
        } else {
            return remotePath + suffix;
        }
    }

    private boolean existsFile(OwnCloudClient client, String remotePath){
        ExistenceCheckRemoteOperation existsOperation =
                new ExistenceCheckRemoteOperation(remotePath, mContext, false);
        RemoteOperationResult result = existsOperation.execute(client);
        return result.isSuccess();
    }

    /**
     * Allows to cancel the actual upload operation. If actual upload operating
     * is in progress it is cancelled, if upload preparation is being performed
     * upload will not take place.
     */
    public void cancel() {
        if (mUploadOperation == null) {
            if (mUploadStarted.get()) {
                Log_OC.d(TAG, "Cancelling upload during upload preparations.");
                mCancellationRequested.set(true);
            } else {
                Log_OC.e(TAG, "No upload in progress. This should not happen.");
            }
        } else {
            Log_OC.d(TAG, "Cancelling upload during actual upload operation.");
            mUploadOperation.cancel();
        }
    }

    /**
     * As soon as this method return true, upload can be cancel via cancel().
     */
    public boolean isUploadInProgress() {
        return mUploadStarted.get();

    }

    /**
     * TODO rewrite with homogeneous fail handling, remove dependency on {@link RemoteOperationResult},
     * TODO     use Exceptions instead
     *
     * @param   sourceFile      Source file to copy.
     * @param   targetFile      Target location to copy the file.
     * @return  {@link RemoteOperationResult}
     * @throws  IOException
     */
    private RemoteOperationResult copy(File sourceFile, File targetFile) throws IOException {
        Log_OC.d(TAG, "Copying local file");

        RemoteOperationResult result = null;

        if (FileStorageUtils.getUsableSpace(mAccount.name) < sourceFile.length()) {
            result = new RemoteOperationResult(ResultCode.LOCAL_STORAGE_FULL);
            return result;  // error condition when the file should be copied

        } else {
            Log_OC.d(TAG, "Creating temporal folder");
            File temporalParent = targetFile.getParentFile();
            temporalParent.mkdirs();
            if (!temporalParent.isDirectory()) {
                throw new IOException(
                        "Unexpected error: parent directory could not be created");
            }
            Log_OC.d(TAG, "Creating temporal file");
            targetFile.createNewFile();
            if (!targetFile.isFile()) {
                throw new IOException(
                        "Unexpected error: target file could not be created");
            }

            Log_OC.d(TAG, "Copying file contents");
            InputStream in = null;
            OutputStream out = null;

            try {
                if (!mOriginalStoragePath.equals(targetFile.getAbsolutePath())) {
                    // In case document provider schema as 'content://'
                    if (mOriginalStoragePath.startsWith(UriUtils.URI_CONTENT_SCHEME)) {
                        Uri uri = Uri.parse(mOriginalStoragePath);
                        in = mContext.getContentResolver().openInputStream(uri);
                    } else {
                        in = new FileInputStream(sourceFile);
                    }
                    out = new FileOutputStream(targetFile);
                    int nRead;
                    byte[] buf = new byte[4096];
                    while (!mCancellationRequested.get() &&
                            (nRead = in.read(buf)) > -1) {
                        out.write(buf, 0, nRead);
                    }
                    out.flush();

                } // else: weird but possible situation, nothing to copy

                if (mCancellationRequested.get()) {
                    result = new RemoteOperationResult(new OperationCancelledException());
                    return result;
                }

            } catch (Exception e) {
                result = new RemoteOperationResult(ResultCode.LOCAL_STORAGE_NOT_COPIED);
                return result;

            } finally {
                try {
                    if (in != null)
                        in.close();
                } catch (Exception e) {
                    Log_OC.d(TAG, "Weird exception while closing input stream for " +
                            mOriginalStoragePath + " (ignoring)", e);
                }
                try {
                    if (out != null)
                        out.close();
                } catch (Exception e) {
                    Log_OC.d(TAG, "Weird exception while closing output stream for " +
                            targetFile.getAbsolutePath() + " (ignoring)", e);
                }
            }
        }
        return result;
    }


    /**
     * TODO rewrite with homogeneous fail handling, remove dependency on {@link RemoteOperationResult},
     * TODO     use Exceptions instead
     *
     * TODO refactor both this and 'copy' in a single method
     *
     * @param   sourceFile      Source file to move.
     * @param   targetFile      Target location to move the file.
     * @return  {@link RemoteOperationResult}
     * @throws  IOException
     */
    private void move(File sourceFile, File targetFile) throws IOException {

        if (!targetFile.equals(sourceFile)) {
            File expectedFolder = targetFile.getParentFile();
            expectedFolder.mkdirs();

            if (expectedFolder.isDirectory()){
                if (!sourceFile.renameTo(targetFile)){
                    // try to copy and then delete
                    targetFile.createNewFile();
                    FileChannel inChannel = new FileInputStream(sourceFile).getChannel();
                    FileChannel outChannel = new FileOutputStream(targetFile).getChannel();
                    try {
                        inChannel.transferTo(0, inChannel.size(), outChannel);
                        sourceFile.delete();
                    } catch (Exception e){
                        mFile.setStoragePath(""); // forget the local file
                        // by now, treat this as a success; the file was uploaded
                        // the best option could be show a warning message
                    }
                    finally {
                        if (inChannel != null) inChannel.close();
                        if (outChannel != null) outChannel.close();
                    }
                }

            } else {
                mFile.setStoragePath("");
            }
        }
    }

    /**
     * Saves a OC File after a successful upload.
     * <p/>
     * A PROPFIND is necessary to keep the props in the local database
     * synchronized with the server, specially the modification time and Etag
     * (where available)
     * <p/>
     */
    private void saveUploadedFile(OwnCloudClient client) {
        OCFile file = mFile;
        if (file.fileExists()) {
            file = getStorageManager().getFileById(file.getFileId());
        }
        long syncDate = System.currentTimeMillis();
        file.setLastSyncDateForData(syncDate);

        // new PROPFIND to keep data consistent with server
        // in theory, should return the same we already have
        // TODO from the appropriate OC server version, get data from last PUT response headers, instead
        // TODO     of a new PROPFIND; the latter may fail, specially for chunked uploads
        ReadRemoteFileOperation operation = new ReadRemoteFileOperation(getRemotePath());
        RemoteOperationResult result = operation.execute(client);
        if (result.isSuccess()) {
            updateOCFile(file, (RemoteFile) result.getData().get(0));
            file.setLastSyncDateForProperties(syncDate);
        } else {
            Log_OC.e(TAG, "Error reading properties of file after successful upload; this is gonna hurt...");
        }

        if (mWasRenamed) {
            OCFile oldFile = getStorageManager().getFileByPath(mOldFile.getRemotePath());
            if (oldFile != null) {
                oldFile.setStoragePath(null);
                getStorageManager().saveFile(oldFile);
                getStorageManager().saveConflict(oldFile, null);
            }
            // else: it was just an automatic renaming due to a name
            // coincidence; nothing else is needed, the storagePath is right
            // in the instance returned by mCurrentUpload.getFile()
        }
        file.setNeedsUpdateThumbnail(true);
        getStorageManager().saveFile(file);
        getStorageManager().saveConflict(file, null);

        FileDataStorageManager.triggerMediaScan(file.getStoragePath());

        // generate new Thumbnail
        final ThumbnailsCacheManager.ThumbnailGenerationTask task =
            new ThumbnailsCacheManager.ThumbnailGenerationTask(getStorageManager(), mAccount);
        task.execute(file);
    }

    private void updateOCFile(OCFile file, RemoteFile remoteFile) {
        file.setCreationTimestamp(remoteFile.getCreationTimestamp());
        file.setFileLength(remoteFile.getLength());
        file.setMimetype(remoteFile.getMimeType());
        file.setModificationTimestamp(remoteFile.getModifiedTimestamp());
        file.setModificationTimestampAtLastSyncForData(remoteFile.getModifiedTimestamp());
        file.setEtag(remoteFile.getEtag());
        file.setRemoteId(remoteFile.getRemoteId());
    }

    public interface OnRenameListener {

        void onRenameUpload();
    }

}