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#pragma once
#include "Framework/Types.hpp"
#include "Framework/Math/Vector.hpp"
#include "Framework/Math/Matrix.hpp"

namespace bpf
{
    namespace math
    {
        /**
         * Represents a viewport for 2D/3D rendering
         * @tparam T the number type
         */
        template <typename T>
        class BP_TPL_API Viewport
        {
        public:
            /**
             * Field of view
             */
            T FOV;

            /**
             * Near clipping plane
             */
            T NearPlane;

            /**
             * Far clipping plane
             */
            T FarPlane;

            /**
             * Viewport width
             */
            fsize Width;

            /**
             * Viewport height
             */
            fsize Height;

            /**
             * Projection matrix
             */
            Matrix4<T> Projection;

            /**
             * Computes the projection of a 3D point on this viewport using the given view matrix
             * @param view the view matrix to use
             * @param pt the 3D point to project
             * @return 2D projected point
             */
            Vector2<T> Project(const Matrix4<T> &view, const Vector3<T> &pt);

            /**
             * Returns the size of this viewport as a vector
             * @return 2D vector storing pixel size in X and Y directions
             */
            inline Vector2<T> GetSize() const
            {
                return (Vector2<T>((T)Width, (T)Height));
            }

            /**
             * Constructs a default viewport
             */
            inline Viewport()
                : FOV(0.0f)
                , NearPlane(0.0f)
                , FarPlane(0.0f)
                , Width(0)
                , Height(0)
                , Projection(Matrix4<T>::Identity)
            {
            }
        };

        using Viewportf = Viewport<float>;
    }
}

#include "Framework/Math/Viewport.impl.hpp"
