//********************************** Banshee Engine (www.banshee3d.com) **************************************************//
//**************** Copyright (c) 2016 Marko Pintera (marko.pintera@gmail.com). All rights reserved. **********************//
#pragma once

#include "Prerequisites/BsPrerequisitesUtil.h"
#include "Math/BsVector3.h"

namespace bs
{
	/** @addtogroup Math
	 *  @{
	 */

	/** A four dimensional vector. */
    class BS_UTILITY_EXPORT Vector4
    {
    public:
        float x, y, z, w;

    public:
		Vector4()
		{ }

        Vector4(BS_ZERO zero)
			:x(0.0f), y(0.0f), z(0.0f), w(0.0f)
        { }

        Vector4(float x, float y, float z, float w)
            :x(x), y(y), z(z), w(w)
        { }

		explicit Vector4(const Vector3& vec, float w = 0.0f)
			:x(vec.x), y(vec.y), z(vec.z), w(w)
		{ }

		/** Exchange the contents of this vector with another. */
		void swap(Vector4& other)
		{
			std::swap(x, other.x);
			std::swap(y, other.y);
			std::swap(z, other.z);
			std::swap(w, other.w);
		}
	
		float operator[] (UINT32 i) const
        {
            assert (i < 4);

            return *(&x+i);
        }

		float& operator[] (UINT32 i)
        {
            assert(i < 4);

            return *(&x+i);
        }

		/** Pointer accessor for direct copying. */
		float* ptr()
		{
			return &x;
		}

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

        Vector4& operator= (const Vector4& rhs)
        {
            x = rhs.x;
            y = rhs.y;
            z = rhs.z;
            w = rhs.w;

            return *this;
        }

		Vector4& operator= (float rhs)
		{
			x = rhs;
			y = rhs;
			z = rhs;
			w = rhs;

			return *this;
		}

        bool operator== (const Vector4& rhs) const
        {
            return (x == rhs.x && y == rhs.y && z == rhs.z && w == rhs.w);
        }

        bool operator!= (const Vector4& rhs) const
        {
            return (x != rhs.x || y != rhs.y || z != rhs.z || w != rhs.w);
        }

        Vector4& operator= (const Vector3& rhs)
        {
            x = rhs.x;
            y = rhs.y;
            z = rhs.z;
            w = 1.0f;

            return *this;
        }

        Vector4 operator+ (const Vector4& rhs) const
        {
            return Vector4(x + rhs.x, y + rhs.y, z + rhs.z, w + rhs.w);
        }

        Vector4 operator- (const Vector4& rhs) const
        {
            return Vector4(x - rhs.x, y - rhs.y, z - rhs.z, w - rhs.w);
        }

        Vector4 operator* (float rhs) const
        {
            return Vector4(x * rhs, y * rhs, z * rhs, w * rhs);
        }

        Vector4 operator* (const Vector4& rhs) const
        {
            return Vector4(rhs.x * x, rhs.y * y, rhs.z * z, rhs.w * w);
        }

        Vector4 operator/ (float rhs) const
        {
            assert(rhs != 0.0f);

            float inv = 1.0f / rhs;
            return Vector4(x * inv, y * inv, z * inv, w * inv);
        }

        Vector4 operator/ (const Vector4& rhs) const
        {
            return Vector4(x / rhs.x, y / rhs.y, z / rhs.z, w / rhs.w);
        }

        const Vector4& operator+ () const
        {
            return *this;
        }

        Vector4 operator- () const
        {
            return Vector4(-x, -y, -z, -w);
        }

        friend Vector4 operator* (float lhs, const Vector4& rhs)
        {
            return Vector4(lhs * rhs.x, lhs * rhs.y, lhs * rhs.z, lhs * rhs.w);
        }

        friend Vector4 operator/ (float lhs, const Vector4& rhs)
        {
            return Vector4(lhs / rhs.x, lhs / rhs.y, lhs / rhs.z, lhs / rhs.w);
        }

        friend Vector4 operator+ (const Vector4& lhs, float rhs)
        {
            return Vector4(lhs.x + rhs, lhs.y + rhs, lhs.z + rhs, lhs.w + rhs);
        }

        friend Vector4 operator+ (float lhs, const Vector4& rhs)
        {
            return Vector4(lhs + rhs.x, lhs + rhs.y, lhs + rhs.z, lhs + rhs.w);
        }

        friend Vector4 operator- (const Vector4& lhs, float rhs)
        {
            return Vector4(lhs.x - rhs, lhs.y - rhs, lhs.z - rhs, lhs.w - rhs);
        }

        friend Vector4 operator- (float lhs, Vector4& rhs)
        {
            return Vector4(lhs - rhs.x, lhs - rhs.y, lhs - rhs.z, lhs - rhs.w);
        }

        Vector4& operator+= (const Vector4& rhs)
        {
            x += rhs.x;
            y += rhs.y;
            z += rhs.z;
            w += rhs.w;

            return *this;
        }

        Vector4& operator-= (const Vector4& rhs)
        {
            x -= rhs.x;
            y -= rhs.y;
            z -= rhs.z;
            w -= rhs.w;

            return *this;
        }

        Vector4& operator*= (float rhs)
        {
            x *= rhs;
            y *= rhs;
            z *= rhs;
            w *= rhs;

            return *this;
        }

        Vector4& operator+= (float rhs)
        {
            x += rhs;
            y += rhs;
            z += rhs;
            w += rhs;

            return *this;
        }

        Vector4& operator-= (float rhs)
        {
            x -= rhs;
            y -= rhs;
            z -= rhs;
            w -= rhs;

            return *this;
        }

        Vector4& operator*= (Vector4& rhs)
        {
            x *= rhs.x;
            y *= rhs.y;
            z *= rhs.z;
            w *= rhs.w;

            return *this;
        }

        Vector4& operator/= (float rhs)
        {
            assert(rhs != 0.0f);

            float inv = 1.0f / rhs;

            x *= inv;
            y *= inv;
            z *= inv;
            w *= inv;

            return *this;
        }

        Vector4& operator/= (const Vector4& rhs)
        {
            x /= rhs.x;
            y /= rhs.y;
            z /= rhs.z;
            w /= rhs.w;

            return *this;
        }

        /** Calculates the dot (scalar) product of this vector with another. */
        float dot(const Vector4& vec) const
        {
            return x * vec.x + y * vec.y + z * vec.z + w * vec.w;
        }

		/** Checks are any of the vector components NaN. */
		inline bool isNaN() const;

        static const Vector4 ZERO;
    };

	/** @} */

	/** @cond SPECIALIZATIONS */
	BS_ALLOW_MEMCPY_SERIALIZATION(Vector4);
	/** @endcond */
}