/*
 * © Copyright 2014 – Urheberrechtshinweis
 * Alle Rechte vorbehalten / All Rights Reserved
 *
 * Programmcode ist urheberrechtlich geschuetzt.
 * Das Urheberrecht liegt, soweit nicht ausdruecklich anders gekennzeichnet, bei Frank Ebner.
 * Keine Verwendung ohne explizite Genehmigung.
 * (vgl. § 106 ff UrhG / § 97 UrhG)
 */

#ifndef INDOOR_MATH_MATRIX3_H
#define INDOOR_MATH_MATRIX3_H


#include <initializer_list>
#include <cmath>
#include "../Assertions.h"

class Matrix3 {

private:

    float data[9];

public:

    Matrix3(std::initializer_list<float> lst) {
        int idx = 0;
        for (float f : lst) {
            data[idx] = f; ++idx;
        }
    }

    static Matrix3 identity() {
		return Matrix3( {1,0,0, 0,1,0, 0,0,1} );
    }

	static Matrix3 getRotationDeg(const float degX, const float degY, const float degZ) {
		return getRotationRad(degX/180.0f*M_PI, degY/180.0f*M_PI, degZ/180.0f*M_PI);
	}

	static Matrix3 getRotationRad(const float radX, const float radY, const float radZ) {

		const float g = radX; const float b = radY; const float a = radZ;
		const float a11 = std::cos(a)*std::cos(b);
		const float a12 = std::cos(a)*std::sin(b)*std::sin(g)-std::sin(a)*std::cos(g);
		const float a13 = std::cos(a)*std::sin(b)*std::cos(g)+std::sin(a)*std::sin(g);
		const float a21 = std::sin(a)*std::cos(b);
		const float a22 = std::sin(a)*std::sin(b)*std::sin(g)+std::cos(a)*std::cos(g);
		const float a23 = std::sin(a)*std::sin(b)*std::cos(g)-std::cos(a)*std::sin(g);
		const float a31 = -std::sin(b);
		const float a32 = std::cos(b)*std::sin(g);
		const float a33 = std::cos(b)*std::cos(g);
		return Matrix3({
		    a11,	a12,	a13,
		    a21,	a22,	a23,
		    a31,	a32,	a33,
		});

	}
	static Matrix3 getRotationVec(const float nx, const float ny, const float nz, const float mag) {
		Assert::isNotNaN(nx, "detected NaN");
		Assert::isNotNaN(ny, "detected NaN");
		Assert::isNotNaN(nz, "detected NaN");
		Assert::isNotNaN(mag, "detected NaN");
		const float c = std::cos(mag);
		const float s = std::sin(mag);
		return Matrix3({
		    c+nx*nx*(1-c),		nx*ny*(1-c)+nz*s,		nx*nz*(1-c)-ny*s,
		    ny*nx*(1-c)-nz*s,	c+ny*ny*(1-c),			ny*nz*(1-c)+nx*s,
		    nz*nx*(1-c)+ny*s,	nz*ny*(1-c)-nx*s,		c+nz*nz*(1-c)
		});
	}
	static Matrix3 getRotationRadX(const float x) {
		return Matrix3({
		    1,		0,		0,
		    0,		cos(x),	-sin(x),
		    0,		sin(x),	cos(x)
		});
	}
	static Matrix3 getRotationRadY(const float y) {
		return Matrix3({
		    cos(y),	0,		sin(y),
		    0,		1,		0,
		    -sin(y),0,		cos(y)
		});
	}
	static Matrix3 getRotationRadZ(const float z) {
		return Matrix3({
		    cos(z),	-sin(z),	0,
		    sin(z),	cos(z),		0,
		    0,		0,			1
		});
	}


	Matrix3 transposed() const {
		return Matrix3({
		    data[0], data[3], data[6],
		    data[1], data[4], data[7],
		    data[2], data[5], data[8]
		});
	}

    static Matrix3 getTranslation(const float x, const float y) {
        return Matrix3({
            1, 0, x,
            0, 1, y,
            0, 0, 1,
        });
    }

    static Matrix3 getScale(const float x, const float y) {
        return Matrix3({
            x, 0, 0,
            0, y, 0,
            0, 0, 1,
        });
    }

    float operator [] (const int idx) const {return data[idx];}

    bool operator == (const Matrix3& o) const {
        for (int i = 0; i < 9; ++i) {
            if (data[i] != o.data[i]) {return false;}
        }
        return true;
    }

	Matrix3 operator * (const float v) const {
		return Matrix3({
			data[0]*v, data[1]*v, data[2]*v,
			data[3]*v, data[4]*v, data[5]*v,
			data[6]*v, data[7]*v, data[8]*v,
		});
	}

	Matrix3 operator + (const Matrix3& m) const {
		return Matrix3({
			data[0]+m.data[0], data[1]+m.data[1], data[2]+m.data[2],
			data[3]+m.data[3], data[4]+m.data[4], data[5]+m.data[5],
			data[6]+m.data[6], data[7]+m.data[7], data[8]+m.data[8],
		});
	}

	Matrix3 operator * (const Matrix3& m) const {
		return Matrix3({
			data[0]*m.data[0] + data[1]*m.data[3] + data[2]*m.data[6],		data[0]*m.data[1] + data[1]*m.data[4] + data[2]*m.data[7],		data[0]*m.data[2] + data[1]*m.data[5] + data[2]*m.data[8],
			data[3]*m.data[0] + data[4]*m.data[3] + data[5]*m.data[6],		data[3]*m.data[1] + data[4]*m.data[4] + data[5]*m.data[7],		data[3]*m.data[2] + data[4]*m.data[5] + data[5]*m.data[8],
			data[6]*m.data[0] + data[7]*m.data[3] + data[8]*m.data[6],		data[6]*m.data[1] + data[7]*m.data[4] + data[8]*m.data[7],		data[6]*m.data[2] + data[7]*m.data[5] + data[8]*m.data[8],
		});
	}

};

struct Vector3 {

    float x,y,z;

    Vector3() : x(0), y(0), z(0) {;}

    Vector3(float x, float y, float z) : x(x), y(y), z(z) {;}

	Vector3 operator + (const Vector3 o) const {
		return Vector3(x+o.x, y+o.y, z+o.z);
	}
	Vector3 operator - (const Vector3 o) const {
		return Vector3(x-o.x, y-o.y, z-o.z);
	}
	Vector3 operator * (const Vector3 o) const {
		return Vector3(x*o.x, y*o.y, z*o.z);
	}


	Vector3 operator * (const float v) const {
		return Vector3(x*v, y*v, z*v);
	}
	Vector3 operator / (const float v) const {
		return Vector3(x/v, y/v, z/v);
	}

	Vector3& operator += (const Vector3 o) {
		this->x += o.x;
		this->y += o.y;
		this->z += o.z;
		return *this;
	}

	Vector3& operator -= (const Vector3 o) {
		this->x -= o.x;
		this->y -= o.y;
		this->z -= o.z;
		return *this;
	}

//	Vector& operator = (const float val) {
//		this->x = val;
//		this->y = val;
//		this->z = val;
//		return *this;
//	}

    bool operator == (const Vector3 o) const {
        return (x==o.x) && (y==o.y) && (z==o.z);
    }

	float norm() const {
		return std::sqrt(x*x + y*y + z*z);
	}

	Vector3 normalized() const {
		const float n = norm();
		return Vector3(x/n, y/n, z/n);
	}

	Vector3 cross(const Vector3 o) const {
		return Vector3(
			y*o.z - z*o.y,
			z*o.x - x*o.z,
			x*o.y - y*o.x
		);
	}

	float dot(const Vector3 o) const {
		return (x*o.x) + (y*o.y) + (z*o.z);
	}

};

inline Vector3 operator * (const Matrix3& mat, const Vector3& vec) {

    return Vector3(
        (mat[ 0]*vec.x + mat[ 1]*vec.y + mat[ 2]*vec.z),
        (mat[ 3]*vec.x + mat[ 4]*vec.y + mat[ 5]*vec.z),
        (mat[ 6]*vec.x + mat[ 7]*vec.y + mat[ 8]*vec.z)
    );

}

//inline Matrix4 operator * (const Matrix4& m1, const Matrix4& m2) {
//    return Matrix4({
//        m1[ 0]*m2[ 0] + m1[ 1]*m2[ 4] + m1[ 2]*m2[ 8] + m1[ 3]*m2[12],		m1[ 0]*m2[ 1] + m1[ 1]*m2[ 5] + m1[ 2]*m2[ 9] + m1[ 3]*m2[13],		m1[ 0]*m2[ 2] + m1[ 1]*m2[ 6] + m1[ 2]*m2[10] + m1[ 3]*m2[14],		m1[ 0]*m2[ 3] + m1[ 1]*m2[ 7] + m1[ 2]*m2[11] + m1[ 3]*m2[15],
//        m1[ 4]*m2[ 0] + m1[ 5]*m2[ 4] + m1[ 6]*m2[ 8] + m1[ 7]*m2[12],		m1[ 4]*m2[ 1] + m1[ 5]*m2[ 5] + m1[ 6]*m2[ 9] + m1[ 7]*m2[13],		m1[ 4]*m2[ 2] + m1[ 5]*m2[ 6] + m1[ 6]*m2[10] + m1[ 7]*m2[14],		m1[ 4]*m2[ 3] + m1[ 5]*m2[ 7] + m1[ 6]*m2[11] + m1[ 7]*m2[15],
//        m1[ 8]*m2[ 0] + m1[ 9]*m2[ 4] + m1[10]*m2[ 8] + m1[11]*m2[12],		m1[ 8]*m2[ 1] + m1[ 9]*m2[ 5] + m1[10]*m2[ 9] + m1[11]*m2[13],		m1[ 8]*m2[ 2] + m1[ 9]*m2[ 6] + m1[10]*m2[10] + m1[11]*m2[14],		m1[ 8]*m2[ 3] + m1[ 9]*m2[ 7] + m1[10]*m2[11] + m1[11]*m2[15],
//        m1[12]*m2[ 0] + m1[13]*m2[ 4] + m1[14]*m2[ 8] + m1[15]*m2[12],		m1[12]*m2[ 1] + m1[13]*m2[ 5] + m1[14]*m2[ 9] + m1[15]*m2[13],		m1[12]*m2[ 2] + m1[13]*m2[ 6] + m1[14]*m2[10] + m1[15]*m2[14],		m1[12]*m2[ 3] + m1[13]*m2[ 7] + m1[14]*m2[11] + m1[15]*m2[15]
//    });
//}

#endif // INDOOR_MATH_MATRIX3_H