/*
 * Copyright (C) 2013 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.camera;

import android.content.ContentResolver;
import android.content.ContentValues;
import android.graphics.BitmapFactory;
import android.location.Location;
import android.net.Uri;
import android.os.AsyncTask;
import android.provider.MediaStore;
import android.provider.MediaStore.Video;

import com.android.camera.app.MediaSaver;
import com.android.camera.data.FilmstripItemData;
import com.android.camera.debug.Log;
import com.android.camera.exif.ExifInterface;

import java.io.File;
import java.io.IOException;

/**
 * A class implementing {@link com.android.camera.app.MediaSaver}.
 */
public class MediaSaverImpl implements MediaSaver {
    private static final Log.Tag TAG = new Log.Tag("MediaSaverImpl");

    /** The memory limit for unsaved image is 30MB. */
    // TODO: Revert this back to 20 MB when CaptureSession API supports saving
    // bursts.
    private static final int SAVE_TASK_MEMORY_LIMIT = 30 * 1024 * 1024;

    private final ContentResolver mContentResolver;

    /** Memory used by the total queued save request, in bytes. */
    private long mMemoryUse;

    private QueueListener mQueueListener;

    /**
     * @param contentResolver The {@link android.content.ContentResolver} to be
     *                 updated.
     */
    public MediaSaverImpl(ContentResolver contentResolver) {
        mContentResolver = contentResolver;
        mMemoryUse = 0;
    }

    @Override
    public boolean isQueueFull() {
        return (mMemoryUse >= SAVE_TASK_MEMORY_LIMIT);
    }

    @Override
    public void addImage(final byte[] data, String title, long date, Location loc, int width,
            int height, int orientation, ExifInterface exif, OnMediaSavedListener l) {
        addImage(data, title, date, loc, width, height, orientation, exif, l,
                FilmstripItemData.MIME_TYPE_JPEG);
    }

    @Override
    public void addImage(final byte[] data, String title, long date, Location loc, int width,
            int height, int orientation, ExifInterface exif, OnMediaSavedListener l,
            String mimeType) {
        if (isQueueFull()) {
            Log.e(TAG, "Cannot add image when the queue is full");
            return;
        }
        ImageSaveTask t = new ImageSaveTask(data, title, date,
                (loc == null) ? null : new Location(loc),
                width, height, orientation, mimeType, exif, mContentResolver, l);

        mMemoryUse += data.length;
        if (isQueueFull()) {
            onQueueFull();
        }
        t.execute();
    }

    @Override
    public void addImage(final byte[] data, String title, long date, Location loc, int orientation,
            ExifInterface exif, OnMediaSavedListener l) {
        // When dimensions are unknown, pass 0 as width and height,
        // and decode image for width and height later in a background thread
        addImage(data, title, date, loc, 0, 0, orientation, exif, l,
                FilmstripItemData.MIME_TYPE_JPEG);
    }
    @Override
    public void addImage(final byte[] data, String title, Location loc, int width, int height,
            int orientation, ExifInterface exif, OnMediaSavedListener l) {
        addImage(data, title, System.currentTimeMillis(), loc, width, height, orientation, exif, l,
                FilmstripItemData.MIME_TYPE_JPEG);
    }

    @Override
    public void addVideo(Uri uri, ContentValues values, OnMediaSavedListener l) {
        // This updates the content resolver for the final saving of the video file.
        new VideoSaveTask(uri, values, l, mContentResolver).execute();
    }

    @Override
    public void setQueueListener(QueueListener l) {
        mQueueListener = l;
        if (l == null) {
            return;
        }
        l.onQueueStatus(isQueueFull());
    }

    private void onQueueFull() {
        if (mQueueListener != null) {
            mQueueListener.onQueueStatus(true);
        }
    }

    private void onQueueAvailable() {
        if (mQueueListener != null) {
            mQueueListener.onQueueStatus(false);
        }
    }

    private class ImageSaveTask extends AsyncTask <Void, Void, Uri> {
        private final byte[] data;
        private final String title;
        private final long date;
        private final Location loc;
        private int width, height;
        private final int orientation;
        private final String mimeType;
        private final ExifInterface exif;
        private final ContentResolver resolver;
        private final OnMediaSavedListener listener;

        public ImageSaveTask(byte[] data, String title, long date, Location loc,
                             int width, int height, int orientation, String mimeType,
                             ExifInterface exif, ContentResolver resolver,
                             OnMediaSavedListener listener) {
            this.data = data;
            this.title = title;
            this.date = date;
            this.loc = loc;
            this.width = width;
            this.height = height;
            this.orientation = orientation;
            this.mimeType = mimeType;
            this.exif = exif;
            this.resolver = resolver;
            this.listener = listener;
        }

        @Override
        protected void onPreExecute() {
            // do nothing.
        }

        @Override
        protected Uri doInBackground(Void... v) {
            if (width == 0 || height == 0) {
                // Decode bounds
                BitmapFactory.Options options = new BitmapFactory.Options();
                options.inJustDecodeBounds = true;
                BitmapFactory.decodeByteArray(data, 0, data.length, options);
                width = options.outWidth;
                height = options.outHeight;
            }
            try {
                return Storage.instance().addImage(
                        resolver, title, date, loc, orientation, exif, data, width, height,
                        mimeType);
            } catch (IOException e) {
                Log.e(TAG, "Failed to write data", e);
                return null;
            }
        }

        @Override
        protected void onPostExecute(Uri uri) {
            if (listener != null) {
                listener.onMediaSaved(uri);
            }
            boolean previouslyFull = isQueueFull();
            mMemoryUse -= data.length;
            if (isQueueFull() != previouslyFull) {
                onQueueAvailable();
            }
        }
    }

    private class VideoSaveTask extends AsyncTask <Void, Void, Void> {
        private final Uri uri;
        private final ContentValues values;
        private final OnMediaSavedListener listener;
        private final ContentResolver resolver;

        public VideoSaveTask(Uri u, ContentValues values, OnMediaSavedListener l,
                             ContentResolver r) {
            this.uri = u;
            this.values = new ContentValues(values);
            this.listener = l;
            this.resolver = r;
        }

        @Override
        protected Void doInBackground(Void... v) {
            try {
                resolver.update(uri, values, null, null);
            } catch (Exception e) {
                // We failed to update the database.
                Log.e(TAG, "failed to update video to media store", e);
            } finally {
                Log.v(TAG, "Current video URI: " + uri);
                return null;
            }
        }

        @Override
        protected void onPostExecute(Void v) {
            if (listener != null) {
                listener.onMediaSaved(uri);
            }
        }
    }
}
