#ifndef Magnum_Color_h
#define Magnum_Color_h
/*
    This file is part of Magnum.

    Copyright © 2010, 2011, 2012, 2013 Vladimír Vondruš <mosra@centrum.cz>

    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.
*/

/** @file
 * @brief Class Magnum::Color3, Magnum::Color4
 */

#include <tuple>

#include "Math/Functions.h"
#include "Math/Vector4.h"
#include "Magnum.h"

namespace Magnum {

namespace Implementation {

/* Convert color from HSV */
template<class T> typename std::enable_if<std::is_floating_point<T>::value, Color3<T>>::type fromHSV(typename Color3<T>::HSV hsv) {
    Math::Deg<T> hue;
    T saturation, value;
    std::tie(hue, saturation, value) = hsv;

    /* Remove repeats */
    hue -= int(T(hue)/T(360))*Math::Deg<T>(360);
    if(hue < Math::Deg<T>(0)) hue += Math::Deg<T>(360);

    int h = int(T(hue)/T(60)) % 6;
    T f = T(hue)/T(60) - h;

    T p = value * (T(1) - saturation);
    T q = value * (T(1) - f*saturation);
    T t = value * (T(1) - (T(1) - f)*saturation);

    switch(h) {
        case 0: return {value, t, p};
        case 1: return {q, value, p};
        case 2: return {p, value, t};
        case 3: return {p, q, value};
        case 4: return {t, p, value};
        case 5: return {value, p, q};
        default: CORRADE_ASSERT_UNREACHABLE();
    }
}
template<class T> inline typename std::enable_if<std::is_integral<T>::value, Color3<T>>::type fromHSV(typename Color3<T>::HSV hsv) {
    return Math::denormalize<Color3<T>>(fromHSV<typename Color3<T>::FloatingPointType>(hsv));
}

/* Internal hue computing function */
template<class T> Math::Deg<T> hue(const Color3<T>& color, T max, T delta) {
    T deltaInv60 = T(60)/delta;

    T hue(0);
    if(delta != T(0)) {
        if(max == color.r())
            hue = (color.g()-color.b())*deltaInv60 + (color.g() < color.b() ? T(360) : T(0));
        else if(max == color.g())
            hue = (color.b()-color.r())*deltaInv60 + T(120);
        else /* max == color.b() */
            hue = (color.r()-color.g())*deltaInv60 + T(240);
    }

    return Math::Deg<T>(hue);
}

/* Hue, saturation, value for floating-point types */
template<class T> inline Math::Deg<T> hue(typename std::enable_if<std::is_floating_point<T>::value, const Color3<T>&>::type color) {
    T max = color.max();
    T delta = max - color.min();
    return hue(color, max, delta);
}
template<class T> inline T saturation(typename std::enable_if<std::is_floating_point<T>::value, const Color3<T>&>::type color) {
    T max = color.max();
    T delta = max - color.min();
    return max != T(0) ? delta/max : T(0);
}
template<class T> inline T value(typename std::enable_if<std::is_floating_point<T>::value, const Color3<T>&>::type color) {
    return color.max();
}

/* Hue, saturation, value for integral types */
template<class T> inline Math::Deg<typename Color3<T>::FloatingPointType> hue(typename std::enable_if<std::is_integral<T>::value, const Color3<T>&>::type color) {
    return hue<typename Color3<T>::FloatingPointType>(Math::normalize<Color3<typename Color3<T>::FloatingPointType>>(color));
}
template<class T> inline typename Color3<T>::FloatingPointType saturation(typename std::enable_if<std::is_integral<T>::value, const Color3<T>&>::type& color) {
    return saturation<typename Color3<T>::FloatingPointType>(Math::normalize<Color3<typename Color3<T>::FloatingPointType>>(color));
}
template<class T> inline typename Color3<T>::FloatingPointType value(typename std::enable_if<std::is_integral<T>::value, const Color3<T>&>::type color) {
    return Math::normalize<typename Color3<T>::FloatingPointType>(color.max());
}

/* Convert color to HSV */
template<class T> inline typename Color3<T>::HSV toHSV(typename std::enable_if<std::is_floating_point<T>::value, const Color3<T>&>::type color) {
    T max = color.max();
    T delta = max - color.min();

    return typename Color3<T>::HSV(hue<typename Color3<T>::FloatingPointType>(color, max, delta), max != T(0) ? delta/max : T(0), max);
}
template<class T> inline typename Color3<T>::HSV toHSV(typename std::enable_if<std::is_integral<T>::value, const Color3<T>&>::type color) {
    return toHSV<typename Color3<T>::FloatingPointType>(Math::normalize<Color3<typename Color3<T>::FloatingPointType>>(color));
}

/* Default alpha value */
template<class T> inline constexpr typename std::enable_if<std::is_floating_point<T>::value, T>::type defaultAlpha() {
    return T(1);
}
template<class T> inline constexpr typename std::enable_if<std::is_integral<T>::value, T>::type defaultAlpha() {
    return std::numeric_limits<T>::max();
}

}

/**
@brief Three-component (RGB) color

The class can store both floating-point (normalized) and integral
(denormalized) representation of color. You can convert between these two
representations using fromNormalized() and fromDenormalized().

Conversion from and to HSV is done always using floating-point types, so hue
is always in range in range @f$ [0.0, 360.0] @f$, saturation and value in
range @f$ [0.0, 1.0] @f$.

@see Color4
*/
/* Not using template specialization because some internal functions are
   impossible to explicitly instantiate */
#ifndef DOXYGEN_GENERATING_OUTPUT
template<class T>
#else
template<class T = Float>
#endif
class Color3: public Math::Vector3<T> {
    public:
        /** @brief Corresponding floating-point type for HSV computation */
        typedef typename Math::TypeTraits<T>::FloatingPointType FloatingPointType;

        /**
         * @brief Type for storing HSV values
         *
         * Hue in range @f$ [0.0, 360.0] @f$, saturation and value in
         * range @f$ [0.0, 1.0] @f$.
         */
        typedef std::tuple<Math::Deg<FloatingPointType>, FloatingPointType, FloatingPointType> HSV;

        /**
         * @brief Create RGB color from HSV representation
         * @param hsv Hue, saturation and value
         *
         * Hue can overflow the range @f$ [0.0, 360.0] @f$.
         */
        constexpr static Color3<T> fromHSV(HSV hsv) {
            return Implementation::fromHSV<T>(hsv);
        }
        /** @overload */
        constexpr static Color3<T> fromHSV(Math::Deg<FloatingPointType> hue, FloatingPointType saturation, FloatingPointType value) {
            return fromHSV(std::make_tuple(hue, saturation, value));
        }

        /**
         * @brief Default constructor
         *
         * All components are set to zero.
         */
        constexpr /*implicit*/ Color3() {}

        /**
         * @brief Gray constructor
         * @param rgb   RGB value
         */
        constexpr explicit Color3(T rgb): Math::Vector3<T>(rgb) {}

        /**
         * @brief Constructor
         * @param r     R value
         * @param g     G value
         * @param b     B value
         */
        constexpr /*implicit*/ Color3(T r, T g, T b): Math::Vector3<T>(r, g, b) {}

        /** @copydoc Math::Vector::Vector(const Vector<size, U>&) */
        template<class U> constexpr explicit Color3(const Math::Vector<3, U>& other): Math::Vector3<T>(other) {}

        /** @brief Copy constructor */
        constexpr Color3(const Math::Vector<3, T>& other): Math::Vector3<T>(other) {}

        T& r() { return Math::Vector3<T>::x(); }                /**< @brief R component */
        constexpr T r() const { return Math::Vector3<T>::x(); } /**< @overload */
        T& g() { return Math::Vector3<T>::y(); }                /**< @brief G component */
        constexpr T g() const { return Math::Vector3<T>::y(); } /**< @overload */
        T& b() { return Math::Vector3<T>::z(); }                /**< @brief B component */
        constexpr T b() const { return Math::Vector3<T>::z(); } /**< @overload */

        /**
         * @brief Convert to HSV
         *
         * Example usage:
         * @code
         * T hue, saturation, value;
         * std::tie(hue, saturation, value) = color.toHSV();
         * @endcode
         *
         * @see hue(), saturation(), value(), fromHSV()
         */
        constexpr HSV toHSV() const {
            return Implementation::toHSV<T>(*this);
        }

        /**
         * @brief Hue
         * @return Hue in range @f$ [0.0, 360.0] @f$.
         *
         * @see saturation(), value(), toHSV(), fromHSV()
         */
        constexpr Math::Deg<FloatingPointType> hue() const {
            return Math::Deg<FloatingPointType>(Implementation::hue<T>(*this));
        }

        /**
         * @brief Saturation
         * @return Saturation in range @f$ [0.0, 1.0] @f$.
         *
         * @see hue(), value(), toHSV(), fromHSV()
         */
        constexpr FloatingPointType saturation() const {
            return Implementation::saturation<T>(*this);
        }

        /**
         * @brief Value
         * @return Value in range @f$ [0.0, 1.0] @f$.
         *
         * @see hue(), saturation(), toHSV(), fromHSV()
         */
        constexpr FloatingPointType value() const {
            return Implementation::value<T>(*this);
        }

        MAGNUM_VECTOR_SUBCLASS_IMPLEMENTATION(Color3, 3)
};

MAGNUM_VECTOR_SUBCLASS_OPERATOR_IMPLEMENTATION(Color3, 3)

/**
@brief Four-component (RGBA) color

See Color3 for more information.
*/
/* Not using template specialization because some internal functions are
   impossible to explicitly instantiate */
#ifndef DOXYGEN_GENERATING_OUTPUT
template<class T>
#else
template<class T = Float>
#endif
class Color4: public Math::Vector4<T> {
    public:
        /** @copydoc Color3::FloatingPointType */
        typedef typename Color3<T>::FloatingPointType FloatingPointType;

        /** @copydoc Color3::HSV */
        typedef typename Color3<T>::HSV HSV;

        /**
         * @copydoc Color3::fromHSV()
         * @param a     Alpha value, defaults to 1.0 for floating-point types
         *      and maximum positive value for integral types.
         */
        constexpr static Color4<T> fromHSV(HSV hsv, T a = Implementation::defaultAlpha<T>()) {
            return Color4<T>(Implementation::fromHSV<T>(hsv), a);
        }
        /** @overload */
        constexpr static Color4<T> fromHSV(Math::Deg<FloatingPointType> hue, FloatingPointType saturation, FloatingPointType value, T alpha) {
            return fromHSV(std::make_tuple(hue, saturation, value), alpha);
        }

        /**
         * @brief Default constructor
         *
         * RGB components are set to zero, A component is set to 1.0 for
         * floating-point types and maximum positive value for integral types.
         */
        constexpr /*implicit*/ Color4(): Math::Vector4<T>(T(0), T(0), T(0), Implementation::defaultAlpha<T>()) {}

        /**
         * @copydoc Color3::Color3(T)
         * @param alpha Alpha value, defaults to 1.0 for floating-point types
         *      and maximum positive value for integral types.
         */
        constexpr explicit Color4(T rgb, T alpha = Implementation::defaultAlpha<T>()): Math::Vector4<T>(rgb, rgb, rgb, alpha) {}

        /**
         * @brief Constructor
         * @param r     R value
         * @param g     G value
         * @param b     B value
         * @param a     A value, defaults to 1.0 for floating-point types and
         *      maximum positive value for integral types.
         */
        constexpr /*implicit*/ Color4(T r, T g, T b, T a = Implementation::defaultAlpha<T>()): Math::Vector4<T>(r, g, b, a) {}

        /**
         * @brief Constructor
         * @param rgb   Three-component color
         * @param a     A value
         */
        /* Not marked as explicit, because conversion from Color3 to Color4
           is fairly common, nearly always with A set to 1 */
        constexpr /*implicit*/ Color4(const Math::Vector3<T>& rgb, T a = Implementation::defaultAlpha<T>()): Math::Vector4<T>(rgb[0], rgb[1], rgb[2], a) {}

        /** @copydoc Math::Vector::Vector(const Vector<size, U>&) */
        template<class U> constexpr explicit Color4(const Math::Vector<4, U>& other): Math::Vector4<T>(other) {}

        /** @brief Copy constructor */
        constexpr Color4(const Math::Vector<4, T>& other): Math::Vector4<T>(other) {}

        T& r() { return Math::Vector4<T>::x(); }                /**< @brief R component */
        constexpr T r() const { return Math::Vector4<T>::x(); } /**< @overload */
        T& g() { return Math::Vector4<T>::y(); }                /**< @brief G component */
        constexpr T g() const { return Math::Vector4<T>::y(); } /**< @overload */
        T& b() { return Math::Vector4<T>::z(); }                /**< @brief B component */
        constexpr T b() const { return Math::Vector4<T>::z(); } /**< @overload */
        T& a() { return Math::Vector4<T>::w(); }                /**< @brief A component */
        constexpr T a() const { return Math::Vector4<T>::w(); } /**< @overload */

        /**
         * @brief RGB part of the vector
         * @return First three components of the vector
         *
         * @see swizzle()
         */
        Color3<T>& rgb() { return Color3<T>::from(Math::Vector4<T>::data()); }
        constexpr Color3<T> rgb() const { return Color3<T>::from(Math::Vector4<T>::data()); } /**< @overload */

        /** @copydoc Color3::toHSV() */
        constexpr HSV toHSV() const {
            return Implementation::toHSV<T>(rgb());
        }

        /** @copydoc Color3::hue() */
        constexpr Math::Deg<FloatingPointType> hue() const {
            return Implementation::hue<T>(rgb());
        }

        /** @copydoc Color3::saturation() */
        constexpr FloatingPointType saturation() const {
            return Implementation::saturation<T>(rgb());
        }

        /** @copydoc Color3::value() */
        constexpr FloatingPointType value() const {
            return Implementation::value<T>(rgb());
        }

        MAGNUM_VECTOR_SUBCLASS_IMPLEMENTATION(Color4, 4)
};

MAGNUM_VECTOR_SUBCLASS_OPERATOR_IMPLEMENTATION(Color4, 4)

/** @debugoperator{Magnum::Color3} */
template<class T> inline Debug operator<<(Debug debug, const Color3<T>& value) {
    return debug << static_cast<const Math::Vector3<T>&>(value);
}

/** @debugoperator{Magnum::Color4} */
template<class T> inline Debug operator<<(Debug debug, const Color4<T>& value) {
    return debug << static_cast<const Math::Vector4<T>&>(value);
}

}

namespace Corrade { namespace Utility {
    /** @configurationvalue{Magnum::Color3} */
    template<class T> struct ConfigurationValue<Magnum::Color3<T>>: public ConfigurationValue<Magnum::Math::Vector<3, T>> {};

    /** @configurationvalue{Magnum::Color4} */
    template<class T> struct ConfigurationValue<Magnum::Color4<T>>: public ConfigurationValue<Magnum::Math::Vector<4, T>> {};
}}

#endif