/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.documentsui.services;

import static com.android.documentsui.base.SharedMinimal.DEBUG;
import static com.android.documentsui.services.FileOperationService.OPERATION_MOVE;

import android.app.Notification;
import android.app.Notification.Builder;
import android.content.ContentResolver;
import android.content.Context;
import android.net.Uri;
import android.os.Messenger;
import android.os.RemoteException;
import android.provider.DocumentsContract;
import android.provider.DocumentsContract.Document;
import android.util.Log;

import com.android.documentsui.Metrics;
import com.android.documentsui.R;
import com.android.documentsui.base.DocumentInfo;
import com.android.documentsui.base.DocumentStack;
import com.android.documentsui.base.Features;
import com.android.documentsui.clipping.UrisSupplier;

import java.io.FileNotFoundException;

import javax.annotation.Nullable;

// TODO: Stop extending CopyJob.
final class MoveJob extends CopyJob {

    private static final String TAG = "MoveJob";

    private final @Nullable Uri mSrcParentUri;

    // mSrcParent may be populated during setup.
    private @Nullable DocumentInfo mSrcParent;

    /**
     * Moves files to a destination identified by {@code destination}.
     * Performs most work by delegating to CopyJob, then deleting
     * a file after it has been copied.
     *
     * @see @link {@link Job} constructor for most param descriptions.
     */
    MoveJob(Context service, Listener listener, String id, DocumentStack destination,
            UrisSupplier srcs, @Nullable Uri srcParent, Messenger messenger, Features features) {
        super(service, listener, id, OPERATION_MOVE, destination, srcs, messenger, features);
        mSrcParentUri = srcParent;
    }

    @Override
    Builder createProgressBuilder() {
        return super.createProgressBuilder(
                service.getString(R.string.move_notification_title),
                R.drawable.ic_menu_copy,
                service.getString(android.R.string.cancel),
                R.drawable.ic_cab_cancel);
    }

    @Override
    public Notification getSetupNotification() {
        return getSetupNotification(service.getString(R.string.move_preparing));
    }

    @Override
    public Notification getProgressNotification() {
        return getProgressNotification(R.string.copy_remaining);
    }

    @Override
    Notification getFailureNotification() {
        return getFailureNotification(
                R.plurals.move_error_notification_title, R.drawable.ic_menu_copy);
    }

    @Override
    public boolean setUp() {
        if (mSrcParentUri != null) {
            final ContentResolver resolver = appContext.getContentResolver();
            try {
                mSrcParent = DocumentInfo.fromUri(resolver, mSrcParentUri);
            } catch (FileNotFoundException e) {
                Log.e(TAG, "Failed to create srcParent.", e);
                failureCount = mResourceUris.getItemCount();
                return false;
            }
        }

        return super.setUp();
    }

    /**
     * {@inheritDoc}
     *
     * Only check space for moves across authorities. For now we don't know if the doc in
     * {@link #mSrcs} is in the same root of destination, and if it's optimized move in the same
     * root it should succeed regardless of free space, but it's for sure a failure if there is no
     * enough free space if docs are moved from another authority.
     */
    @Override
    boolean checkSpace() {
        long size = 0;
        for (DocumentInfo src : mResolvedDocs) {
            if (!src.authority.equals(stack.getRoot().authority)) {
                if (src.isDirectory()) {
                    try {
                        size += calculateFileSizesRecursively(getClient(src), src.derivedUri);
                    } catch (RemoteException|ResourceException e) {
                        Log.w(TAG, "Failed to obtain client for %s" + src.derivedUri + ".", e);

                        // Failed to calculate size, but move may still succeed.
                        return true;
                    }
                } else {
                    size += src.size;
                }
            }
        }

        return verifySpaceAvailable(size);
    }

    void processDocument(DocumentInfo src, DocumentInfo srcParent, DocumentInfo dest)
            throws ResourceException {

        // TODO: When optimized move kicks in, we're not making any progress updates. FIX IT!

        // When moving within the same provider, try to use optimized moving.
        // If not supported, then fallback to byte-by-byte copy/move.
        if (src.authority.equals(dest.authority) && (srcParent != null || mSrcParent != null)) {
            if ((src.flags & Document.FLAG_SUPPORTS_MOVE) != 0) {
                try {
                    if (DocumentsContract.moveDocument(getClient(src), src.derivedUri,
                            srcParent != null ? srcParent.derivedUri : mSrcParent.derivedUri,
                            dest.derivedUri) != null) {
                        Metrics.logFileOperated(
                                appContext, operationType, Metrics.OPMODE_PROVIDER);
                        return;
                    }
                } catch (RemoteException | RuntimeException e) {
                    Metrics.logFileOperationFailure(
                            appContext, Metrics.SUBFILEOP_QUICK_MOVE, src.derivedUri);
                    Log.e(TAG, "Provider side move failed for: " + src.derivedUri
                            + " due to an exception: ", e);
                }
                // If optimized move fails, then fallback to byte-by-byte copy.
                if (DEBUG) Log.d(TAG, "Fallback to byte-by-byte move for: " + src.derivedUri);
            }
        }

        // Moving virtual files by bytes is not supported. This is because, it would involve
        // conversion, and the source file should not be deleted in such case (as it's a different
        // file).
        if (src.isVirtual()) {
            throw new ResourceException("Cannot move virtual file %s byte by byte.",
                    src.derivedUri);
        }

        // If we couldn't do an optimized copy...we fall back to vanilla byte copy.
        byteCopyDocument(src, dest);

        // Remove the source document.
        if(!isCanceled()) {
            deleteDocument(src, srcParent);
        }
    }

    @Override
    public String toString() {
        return new StringBuilder()
                .append("MoveJob")
                .append("{")
                .append("id=" + id)
                .append(", uris=" + mResourceUris)
                .append(", docs=" + mResolvedDocs)
                .append(", srcParent=" + mSrcParent)
                .append(", destination=" + stack)
                .append("}")
                .toString();
    }
}