csscolorparser.hpp

// (c) Dean McNamee <dean@gmail.com>, 2012.
// C++ port by Mapbox, Konstantin Käfer <mail@kkaefer.com>, 2014-2017.
//
// https://github.com/deanm/css-color-parser-js
// https://github.com/kkaefer/css-color-parser-cpp
//
// 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
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// IN THE SOFTWARE.

#ifndef CSS_COLOR_PARSER_CPP
#define CSS_COLOR_PARSER_CPP

#include <string>
#include <cmath>
#include <experimental/optional>

namespace CSSColorParser {

template <class T>
using optional = std::experimental::optional<T>;

struct Color {
    inline Color() {
    }
    inline Color(unsigned char r_, unsigned char g_, unsigned char b_, float a_)
        : r(r_), g(g_), b(b_), a(a_ > 1 ? 1 : a_ < 0 ? 0 : a_) {
    }
    unsigned char r = 0, g = 0, b = 0;
    float a = 1.0f;
};

inline bool operator==(const Color& lhs, const Color& rhs) {
    return lhs.r == rhs.r && lhs.g == rhs.g && lhs.b == rhs.b && ::fabs(lhs.a - rhs.a) < 0.0001f;
}

inline bool operator!=(const Color& lhs, const Color& rhs) {
    return !(lhs == rhs);
}

optional<Color> parse(const std::string& css_str);

} // namespace CSSColorParser

#endif