/**
 * Copyright (c) 2011, The University of Southampton and the individual contributors.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   *  Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *   *  Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *
 *   *  Neither the name of the University of Southampton nor the names of its
 *      contributors may be used to endorse or promote products derived from this
 *      software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
/**
 * 
 */
package org.openimaj.video;

import java.util.ArrayList;
import java.util.List;

import org.openimaj.image.Image;
import org.openimaj.video.timecode.VideoTimecode;

/**
 *      This class represents a cache of video material. It is also able to
 *      build the cache for you with the static methods.
 *
 *      @author David Dupplaw (dpd@ecs.soton.ac.uk)
 *      
 *      @created 14 Oct 2011
 *
 *      @param <I> The type of video frames to be cached
 */
public class VideoCache<I extends Image<?,I>> extends VideoWriter<I>
{
        /** The cached frames */
        private List<I> frames = new ArrayList<I>();
        
        /**
         *      Create a video cache for frames of the given size and for a video
         *      of the given frame rate.
         * 
         *      @param width The width of the video frames
         *      @param height The height of the video frames
         *      @param frameRate The frame rate of the video
         */
        public VideoCache( int width, int height, double frameRate )
        {
                super( width, height, frameRate );
        }

        /**
         *      {@inheritDoc}
         *      @see org.openimaj.video.VideoWriter#addFrame(org.openimaj.image.Image)
         */
        @Override
        public void addFrame( I frame )
        {
                frames.add( frame );
        }
        
        /**
         *      Returns an {@link ArrayBackedVideo} for the frames in this cache.
         *      @return An {@link ArrayBackedVideo}
         */
        @SuppressWarnings( "unchecked" )
        public ArrayBackedVideo<I> getArrayBackedVideo()
        {
                return new ArrayBackedVideo<I>( (I[])frames.toArray(), frameRate );
        }
        
        /**
         *      Returns the number of frames that have been cached.
         *      @return The number of frames that have been cached.
         */
        public int getNumberOfFrames()
        {
                return frames.size();
        }
        
        /**
         *      Returns the frame at the given index.
         *      @param i The index to get the frame from
         *      @return The frame at the given index
         */
        public I getFrame( int i )
        {
                return frames.get(i);
        }
        
        /**
         *      Clears the cache.
         *      {@inheritDoc}
         *      @see org.openimaj.video.processor.VideoProcessor#reset()
         */
        @Override
        public void reset()
        {
                frames.clear();
        }

        /**
         *      Cache the whole of the given video.
         *  @param <I> Type of {@link Image} 
         * 
         *      @param video The video to cache
         *      @return A {@link VideoCache}
         */
        public static <I extends Image<?,I>> VideoCache<I> cacheVideo( Video<I> video )
        {
                VideoCache<I> vc = new VideoCache<I>( video.getWidth(), 
                                video.getHeight(), video.getFPS() );
                video.reset();
                while( video.hasNextFrame() )
                        vc.addFrame( video.getNextFrame().clone() );
                return vc;
        }
        
        /**
         *      Cache the given time range from the given video.
         * 
         *      @param <I> The type of the video frames
         *      @param video The video to cache
         *      @param start The start of the video to cache
         *      @param end The end of the video to cache
         *      @return A {@link VideoCache}
         */
        public static <I extends Image<?,I>> VideoCache<I> cacheVideo( Video<I> video,
                        VideoTimecode start, VideoTimecode end )
        {
                VideoCache<I> vc = new VideoCache<I>( video.getWidth(), 
                                video.getHeight(), video.getFPS() );
                video.setCurrentFrameIndex( start.getFrameNumber() );
                while( video.hasNextFrame() && 
                           video.getCurrentFrameIndex() < end.getFrameNumber() )
                        vc.addFrame( video.getNextFrame().clone() );
                return vc;
        }
}