/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2009 Torus Knot Software Ltd

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
-----------------------------------------------------------------------------
*/
#ifndef _COLOURVALUE_H__
#define _COLOURVALUE_H__

#include "OgrePrerequisites.h"

namespace Ogre {
	/** \addtogroup Core
	*  @{
	*/
	/** \addtogroup General
	*  @{
	*/

    typedef uint32 RGBA;
    typedef uint32 ARGB;
    typedef uint32 ABGR;
	typedef uint32 BGRA;

    /** Class representing colour.
	    @remarks
		    Colour is represented as 4 components, each of which is a
		    floating-point value from 0.0 to 1.0.
	    @par
		    The 3 'normal' colour components are red, green and blue, a higher
		    number indicating greater amounts of that component in the colour.
		    The forth component is the 'alpha' value, which represents
		    transparency. In this case, 0.0 is completely transparent and 1.0 is
		    fully opaque.
    */
    class _OgreExport ColourValue
    {
    public:
        static const ColourValue ZERO;
        static const ColourValue Black;
        static const ColourValue White;
        static const ColourValue Red;
        static const ColourValue Green;
        static const ColourValue Blue;

	    explicit ColourValue( float red = 1.0f,
				    float green = 1.0f,
				    float blue = 1.0f,
				    float alpha = 1.0f ) : r(red), g(green), b(blue), a(alpha)
        { }

	    bool operator==(const ColourValue& rhs) const;
	    bool operator!=(const ColourValue& rhs) const;

        float r,g,b,a;

	    /** Retrieves colour as RGBA.
	    */
	    RGBA getAsRGBA(void) const;

	    /** Retrieves colour as ARGB.
	    */
	    ARGB getAsARGB(void) const;

		/** Retrieves colour as BGRA.
		*/
		BGRA getAsBGRA(void) const;

		/** Retrieves colours as ABGR */
	    ABGR getAsABGR(void) const;

	    /** Sets colour as RGBA.
	    */
        void setAsRGBA(const RGBA val);

	    /** Sets colour as ARGB.
	    */
        void setAsARGB(const ARGB val);

		/** Sets colour as BGRA.
		*/
		void setAsBGRA(const BGRA val);

	    /** Sets colour as ABGR.
	    */
        void setAsABGR(const ABGR val);

        /** Clamps colour value to the range [0, 1].
        */
        void saturate(void)
        {
            if (r < 0)
                r = 0;
            else if (r > 1)
                r = 1;

            if (g < 0)
                g = 0;
            else if (g > 1)
                g = 1;

            if (b < 0)
                b = 0;
            else if (b > 1)
                b = 1;

            if (a < 0)
                a = 0;
            else if (a > 1)
                a = 1;
        }

        /** As saturate, except that this colour value is unaffected and
            the saturated colour value is returned as a copy. */
        ColourValue saturateCopy(void) const
        {
            ColourValue ret = *this;
            ret.saturate();
            return ret;
        }

		/// Array accessor operator
		inline float operator [] ( const size_t i ) const
		{
			assert( i < 4 );

			return *(&r+i);
		}

		/// Array accessor operator
		inline float& operator [] ( const size_t i )
		{
			assert( i < 4 );

			return *(&r+i);
		}

		/// Pointer accessor for direct copying
		inline float* ptr()
		{
			return &r;
		}
		/// Pointer accessor for direct copying
		inline const float* ptr() const
		{
			return &r;
		}

		
		// arithmetic operations
        inline ColourValue operator + ( const ColourValue& rkVector ) const
        {
            ColourValue kSum;

            kSum.r = r + rkVector.r;
            kSum.g = g + rkVector.g;
            kSum.b = b + rkVector.b;
            kSum.a = a + rkVector.a;

            return kSum;
        }

        inline ColourValue operator - ( const ColourValue& rkVector ) const
        {
            ColourValue kDiff;

            kDiff.r = r - rkVector.r;
            kDiff.g = g - rkVector.g;
            kDiff.b = b - rkVector.b;
            kDiff.a = a - rkVector.a;

            return kDiff;
        }

        inline ColourValue operator * (const float fScalar ) const
        {
            ColourValue kProd;

            kProd.r = fScalar*r;
            kProd.g = fScalar*g;
            kProd.b = fScalar*b;
            kProd.a = fScalar*a;

            return kProd;
        }

        inline ColourValue operator * ( const ColourValue& rhs) const
        {
            ColourValue kProd;

            kProd.r = rhs.r * r;
            kProd.g = rhs.g * g;
            kProd.b = rhs.b * b;
            kProd.a = rhs.a * a;

            return kProd;
        }

        inline ColourValue operator / ( const ColourValue& rhs) const
        {
            ColourValue kProd;

            kProd.r = rhs.r / r;
            kProd.g = rhs.g / g;
            kProd.b = rhs.b / b;
            kProd.a = rhs.a / a;

            return kProd;
        }

        inline ColourValue operator / (const float fScalar ) const
        {
            assert( fScalar != 0.0 );

            ColourValue kDiv;

            float fInv = 1.0f / fScalar;
            kDiv.r = r * fInv;
            kDiv.g = g * fInv;
            kDiv.b = b * fInv;
            kDiv.a = a * fInv;

            return kDiv;
        }

        inline friend ColourValue operator * (const float fScalar, const ColourValue& rkVector )
        {
            ColourValue kProd;

            kProd.r = fScalar * rkVector.r;
            kProd.g = fScalar * rkVector.g;
            kProd.b = fScalar * rkVector.b;
            kProd.a = fScalar * rkVector.a;

            return kProd;
        }

        // arithmetic updates
        inline ColourValue& operator += ( const ColourValue& rkVector )
        {
            r += rkVector.r;
            g += rkVector.g;
            b += rkVector.b;
            a += rkVector.a;

            return *this;
        }

        inline ColourValue& operator -= ( const ColourValue& rkVector )
        {
            r -= rkVector.r;
            g -= rkVector.g;
            b -= rkVector.b;
            a -= rkVector.a;

            return *this;
        }

        inline ColourValue& operator *= (const float fScalar )
        {
            r *= fScalar;
            g *= fScalar;
            b *= fScalar;
            a *= fScalar;
            return *this;
        }

        inline ColourValue& operator /= (const float fScalar )
        {
            assert( fScalar != 0.0 );

            float fInv = 1.0f / fScalar;

            r *= fInv;
            g *= fInv;
            b *= fInv;
            a *= fInv;

            return *this;
        }

		/** Set a colour value from Hue, Saturation and Brightness.
		@param hue Hue value, scaled to the [0,1] range as opposed to the 0-360
		@param saturation Saturation level, [0,1]
		@param brightness Brightness level, [0,1]
		*/
		void setHSB(Real hue, Real saturation, Real brightness);

		/** Convert the current colour to Hue, Saturation and Brightness values. 
		@param hue Output hue value, scaled to the [0,1] range as opposed to the 0-360
		@param saturation Output saturation level, [0,1]
		@param brightness Output brightness level, [0,1]
		*/
		void getHSB(Real* hue, Real* saturation, Real* brightness) const;



		/** Function for writing to a stream.
		*/
		inline _OgreExport friend std::ostream& operator <<
			( std::ostream& o, const ColourValue& c )
		{
			o << "ColourValue(" << c.r << ", " << c.g << ", " << c.b << ", " << c.a << ")";
			return o;
		}

    };
	/** @} */
	/** @} */

} // namespace

#endif
