/*
    Copyright (C) 2012 Carl Hetherington <cth@carlh.net>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    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, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include <iostream>
#include <boost/shared_ptr.hpp>
#include "ab_transcoder.h"
#include "film.h"
#include "decoder.h"
#include "encoder.h"
#include "job.h"
#include "options.h"
#include "image.h"
#include "decoder_factory.h"

/** @file src/ab_transcoder.cc
 *  @brief A transcoder which uses one Film for the left half of the screen, and a different one
 *  for the right half (to facilitate A/B comparisons of settings)
 */

using std::string;
using boost::shared_ptr;

/** @param a Film to use for the left half of the screen.
 *  @param b Film to use for the right half of the screen.
 *  @param o Options.
 *  @param j Job that we are associated with.
 *  @param e Encoder to use.
 */

ABTranscoder::ABTranscoder (
	shared_ptr<Film> a, shared_ptr<Film> b, shared_ptr<const Options> o, Job* j, shared_ptr<Encoder> e)
	: _film_a (a)
	, _film_b (b)
	, _opt (o)
	, _job (j)
	, _encoder (e)
	, _last_frame (0)
{
	_da = decoder_factory (_film_a, o, j);
	_db = decoder_factory (_film_b, o, j);

	_da->Video.connect (bind (&ABTranscoder::process_video, this, _1, _2, _3, 0));
	_db->Video.connect (bind (&ABTranscoder::process_video, this, _1, _2, _3, 1));
	_da->Audio.connect (bind (&Encoder::process_audio, e, _1));
}

ABTranscoder::~ABTranscoder ()
{

}

void
ABTranscoder::process_video (shared_ptr<Image> yuv, int frame, shared_ptr<Subtitle> sub, int index)
{
	if (index == 0) {
		/* Keep this image around until we get the other half */
		_image = yuv;
	} else {
		/* Copy the right half of yuv into _image */
		for (int i = 0; i < yuv->components(); ++i) {
			int const line_size = yuv->line_size()[i];
			int const half_line_size = line_size / 2;
			int const stride = yuv->stride()[i];

			uint8_t* p = _image->data()[i];
			uint8_t* q = yuv->data()[i];
			
			for (int j = 0; j < yuv->lines (i); ++j) {
				memcpy (p + half_line_size, q + half_line_size, half_line_size);
				p += stride;
				q += stride;
			}
		}
			
		/* And pass it to the encoder */
		_encoder->process_video (_image, frame, sub);
		_image.reset ();
	}
	
	_last_frame = frame;
}


void
ABTranscoder::go ()
{
	_encoder->process_begin (_da->audio_channel_layout());
	_da->process_begin ();
	_db->process_begin ();
	
	while (1) {
		bool const a = _da->pass ();
		bool const b = _db->pass ();

		if (a && b) {
			break;
		}
	}

	_encoder->process_end ();
	_da->process_end ();
	_db->process_end ();
}