// Copyright (c) 2016-2018 Ember - Nomango
//
// 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.

#pragma once
#include <math/Vec2.hpp>
#include <math/Matrix.hpp>

namespace ember
{
    namespace math
    {

        /**
         * \~chinese
         * @brief 二维放射变换
         */
        template <typename _Ty>
        class TransformT
        {
        public:
            using ValueType = _Ty;

            float rotation;            ///< 旋转
            Vec2T<ValueType> position; ///< 坐标
            Vec2T<ValueType> scale;    ///< 缩放
            Vec2T<ValueType> skew;     ///< 错切角度

        public:
            TransformT();

            /// \~chinese
            /// @brief 将二维放射变换转换为矩阵
            Matrix3x2T<ValueType> ToMatrix() const;

            bool IsFast() const;

            bool operator==(const TransformT &rhs) const;
        };

        template <typename _Ty>
        inline TransformT<_Ty>::TransformT()
            : position(), rotation(0.f), scale(1.f, 1.f), skew(0.f, 0.f)
        {
        }

        template <typename _Ty>
        Matrix3x2T<_Ty> TransformT<_Ty>::ToMatrix() const
        {
            if (!skew.IsOrigin())
            {
                return Matrix3x2T<_Ty>::Skewing(skew) * Matrix3x2T<_Ty>::SRT(position, scale, rotation);
            }
            return Matrix3x2T<_Ty>::SRT(position, scale, rotation);
        }

        template <typename _Ty>
        inline bool TransformT<_Ty>::IsFast() const
        {
            return skew.x == 0.f && skew.y == 0.f && scale.x == 1.f && scale.y == 1.f && rotation == 0.f;
        }

        template <typename _Ty>
        bool TransformT<_Ty>::operator==(const TransformT &rhs) const
        {
            return position == rhs.position && rotation == rhs.rotation && scale == rhs.scale && skew == rhs.skew;
        }

    } // namespace math
} // namespace ember