/*
    Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>

    This file is part of DCP-o-matic.

    DCP-o-matic 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.

    DCP-o-matic 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 DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.

*/


#ifndef DCPOMATIC_FRAME_RATE_CHANGE_H
#define DCPOMATIC_FRAME_RATE_CHANGE_H


#include <memory>
#include <string>


class Content;
class Film;


class FrameRateChange
{
public:
	FrameRateChange();
	FrameRateChange(double, int);
	FrameRateChange(std::shared_ptr<const Film> film, std::shared_ptr<const Content> content);
	FrameRateChange(std::shared_ptr<const Film> film, Content const * content);

	/** @return factor by which to multiply a source frame rate
	    to get the effective rate after any skip or repeat has happened.
	*/
	double factor() const {
		if (_skip > 0) {
			return 1.0 / (_skip + 1);
		}

		return _repeat;
	}

	std::string description() const;

	int skip() const {
		return _skip;
	}

	int repeat() const {
		return _repeat;
	}

	double speed_up() const {
		return _speed_up;
	}

	bool change_speed() const {
		return _change_speed;
	}

	double source() const {
		return _source;
	}

	int dcp() const {
		return _dcp;
	}

private:
	double _source = 24;
	int _dcp = 24;

	/** Frames to skip between each one to use, e.g.
	 *  0 to skip no frames, 1 to skip every other one, 2 to skip 2 out of 3, etc.
	 */
	int _skip = 0;
	/** number of times to use each frame (e.g. 1 is normal, 2 means repeat each frame once, and so on) */
	int _repeat = 1;
	/** true if this DCP will run its video faster or slower than the source
	 *  without taking into account `repeat' nor `skip'.
	 *  (e.g. change_speed will be true if
	 *	    source is 29.97fps, DCP is 30fps
	 *	    source is 14.50fps, DCP is 30fps
	 *  but not if
	 *	    source is 15.00fps, DCP is 30fps
	 *	    source is 12.50fps, DCP is 25fps)
	 */
	bool _change_speed = false;

	/** Amount by which the video is being sped-up in the DCP; e.g. for a
	 *  24fps source in a 25fps DCP this would be 25/24.
	 */
	double _speed_up = 1.0;
};


#endif