/*
    Copyright (C) 2014-2015 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.

*/

/** @file  src/colour_conversion.h
 *  @brief ColourConversion class.
 */

#ifndef DCP_COLOUR_CONVERSION_H
#define DCP_COLOUR_CONVERSION_H

#include "chromaticity.h"
#include <boost/shared_ptr.hpp>
#include <boost/numeric/ublas/matrix.hpp>
#include <boost/optional.hpp>

namespace dcp {

class TransferFunction;

enum YUVToRGB {
	YUV_TO_RGB_REC601,
	YUV_TO_RGB_REC709,
	YUV_TO_RGB_COUNT
};

/** @class ColourConversion
 *  @brief A representation of all the parameters involved the colourspace conversion
 *  of a YUV image to XYZ (via RGB).
 */
class ColourConversion
{
public:
	ColourConversion ()
		: _yuv_to_rgb (YUV_TO_RGB_REC601)
	{}

	ColourConversion (
		boost::shared_ptr<const TransferFunction> in,
		YUVToRGB yuv_to_rgb,
		Chromaticity red,
		Chromaticity green,
		Chromaticity blue,
		Chromaticity white,
		boost::optional<Chromaticity> adjusted_white,
		boost::shared_ptr<const TransferFunction> out
		);

	boost::shared_ptr<const TransferFunction> in () const {
		return _in;
	}

	YUVToRGB yuv_to_rgb () const {
		return _yuv_to_rgb;
	}

	Chromaticity red () const {
		return _red;
	}

	Chromaticity green () const {
		return _green;
	}

	Chromaticity blue () const {
		return _blue;
	}

	Chromaticity white () const {
		return _white;
	}

	boost::optional<Chromaticity> adjusted_white () const {
		return _adjusted_white;
	}

	boost::shared_ptr<const TransferFunction> out () const {
		return _out;
	}

	void set_in (boost::shared_ptr<const TransferFunction> f) {
		_in = f;
	}

	void set_yuv_to_rgb (YUVToRGB y) {
		_yuv_to_rgb = y;
	}

	void set_red (Chromaticity red) {
		_red = red;
	}

	void set_green (Chromaticity green) {
		_green = green;
	}

	void set_blue (Chromaticity blue) {
		_blue = blue;
	}

	void set_white (Chromaticity white) {
		_white = white;
	}

	void set_adjusted_white (Chromaticity adjusted_white) {
		_adjusted_white = adjusted_white;
	}

	void unset_adjusted_white () {
		_adjusted_white = boost::optional<Chromaticity> ();
	}

	void set_out (boost::shared_ptr<const TransferFunction> f) {
		_out = f;
	}

	bool about_equal (ColourConversion const & other, float epsilon) const;

	boost::numeric::ublas::matrix<double> rgb_to_xyz () const;
	boost::numeric::ublas::matrix<double> xyz_to_rgb () const;
	boost::numeric::ublas::matrix<double> bradford () const;

	static ColourConversion const & srgb_to_xyz ();
	static ColourConversion const & rec601_to_xyz ();
	static ColourConversion const & rec709_to_xyz ();
	static ColourConversion const & p3_to_xyz ();

protected:
	/** Input transfer function (probably a gamma function, or something similar) */
	boost::shared_ptr<const TransferFunction> _in;
	/** Conversion to use from YUV to RGB */
	YUVToRGB _yuv_to_rgb;
	Chromaticity _red;
	Chromaticity _green;
	Chromaticity _blue;
	Chromaticity _white;
	/** White point that we are adjusting to using a Bradford matrix */
	boost::optional<Chromaticity> _adjusted_white;
	/** Output transfer function (probably an inverse gamma function, or something similar) */
	boost::shared_ptr<const TransferFunction> _out;
};

}

#endif