#ifndef _BASIC_GEOMETRY_MATRIX2X2_H_
#define _BASIC_GEOMETRY_MATRIX2X2_H_

#include "angle.h"
#include "vector2.h"
#include "matrixes.h"

// =================== Reset ==================== //

inline void matrix2x2_reset_fp32(matrix2x2_fp32_t* matrix)
{
    matrix->r1c1 = 0.0f;
    matrix->r1c2 = 0.0f;
    matrix->r2c1 = 0.0f;
    matrix->r2c2 = 0.0f;
}

inline void matrix2x2_reset_fp64(matrix2x2_fp64_t* matrix)
{
    matrix->r1c1 = 0.0;
    matrix->r1c2 = 0.0;
    matrix->r2c1 = 0.0;
    matrix->r2c2 = 0.0;
}

// ================== Identity ================== //

inline void matrix2x2_set_to_identity_fp32(matrix2x2_fp32_t* matrix)
{
    matrix->r1c1 = 1.0f;
    matrix->r1c2 = 0.0f;
    matrix->r2c1 = 0.0f;
    matrix->r2c2 = 1.0f;
}

inline void matrix2x2_set_to_identity_fp64(matrix2x2_fp64_t* matrix)
{
    matrix->r1c1 = 1.0;
    matrix->r1c2 = 0.0;
    matrix->r2c1 = 0.0;
    matrix->r2c2 = 1.0;
}

// ================ Make Diagonal =============== //

inline void matrix2x2_set_to_diagonal_fp32(const float d1, const float d2, matrix2x2_fp32_t* matrix)
{
    matrix->r1c1 = d1;
    matrix->r1c2 = 0.0f;
    matrix->r2c1 = 0.0f;
    matrix->r2c2 = d2;
}

inline void matrix2x2_set_to_diagonal_fp64(const double d1, const double d2, matrix2x2_fp64_t* matrix)
{
    matrix->r1c1 = d1;
    matrix->r1c2 = 0.0;
    matrix->r2c1 = 0.0;
    matrix->r2c2 = d2;
}

// ============== Rotation Matrix =============== //

inline void matrix2x2_make_rotation_fp32(const float angle, const angle_unit_t unit, matrix2x2_fp32_t* matrix)
{
    const float radians = fp32_angle_to_radians(angle, unit);
    const float cosine = cosf(radians);
    const float sine = sinf(radians);

    matrix->r1c1 = cosine;
    matrix->r1c2 = -sine;
    matrix->r2c1 = sine;
    matrix->r2c2 = cosine;
}

inline void matrix2x2_make_rotation_fp64(const double angle, const angle_unit_t unit, matrix2x2_fp64_t* matrix)
{
    const double radians = fp64_angle_to_radians(angle, unit);
    const double cosine = cos(radians);
    const double sine = sin(radians);

    matrix->r1c1 = cosine;
    matrix->r1c2 = -sine;
    matrix->r2c1 = sine;
    matrix->r2c2 = cosine;
}

// ==================== Copy ==================== //

inline void matrix2x2_copy_fp32(const matrix2x2_fp32_t* from, matrix2x2_fp32_t* to)
{
    to->r1c1 = from->r1c1;
    to->r1c2 = from->r1c2;

    to->r2c1 = from->r2c1;
    to->r2c2 = from->r2c2;
}

inline void matrix2x2_copy_fp64(const matrix2x2_fp64_t* from, matrix2x2_fp64_t* to)
{
    to->r1c1 = from->r1c1;
    to->r1c2 = from->r1c2;

    to->r2c1 = from->r2c1;
    to->r2c2 = from->r2c2;
}

// ==================== Swap ==================== //

inline void matrix2x2_swap_fp32(matrix2x2_fp32_t* matrix1, matrix2x2_fp32_t* matrix2)
{
    const float r1c1 = matrix2->r1c1;
    const float r1c2 = matrix2->r1c2;

    const float r2c1 = matrix2->r2c1;
    const float r2c2 = matrix2->r2c2;

    matrix2->r1c1 = matrix1->r1c1;
    matrix2->r1c2 = matrix1->r1c2;

    matrix2->r2c1 = matrix1->r2c1;
    matrix2->r2c2 = matrix1->r2c2;

    matrix1->r1c1 = r1c1;
    matrix1->r1c2 = r1c2;

    matrix1->r2c1 = r2c1;
    matrix1->r2c2 = r2c2;
}

inline void matrix2x2_swap_fp64(matrix2x2_fp64_t* matrix1, matrix2x2_fp64_t* matrix2)
{
    const double r1c1 = matrix2->r1c1;
    const double r1c2 = matrix2->r1c2;

    const double r2c1 = matrix2->r2c1;
    const double r2c2 = matrix2->r2c2;

    matrix2->r1c1 = matrix1->r1c1;
    matrix2->r1c2 = matrix1->r1c2;

    matrix2->r2c1 = matrix1->r2c1;
    matrix2->r2c2 = matrix1->r2c2;

    matrix1->r1c1 = r1c1;
    matrix1->r1c2 = r1c2;

    matrix1->r2c1 = r2c1;
    matrix1->r2c2 = r2c2;
}

// ============= Copy to twin type ============== //

inline void matrix2x2_convert_fp64_to_fp32(const matrix2x2_fp64_t* from, matrix2x2_fp32_t* to)
{
    to->r1c1 = (float)from->r1c1;
    to->r1c2 = (float)from->r1c2;

    to->r2c1 = (float)from->r2c1;
    to->r2c2 = (float)from->r2c2;
}

inline void matrix2x2_convert_fp32_to_fp64(const matrix2x2_fp32_t* from, matrix2x2_fp64_t* to)
{
    to->r1c1 = from->r1c1;
    to->r1c2 = from->r1c2;

    to->r2c1 = from->r2c1;
    to->r2c2 = from->r2c2;
}

// ================ Determinant ================= //

inline float matrix2x2_get_determinant_fp32(const matrix2x2_fp32_t* matrix)
{
    return matrix->r1c1 * matrix->r2c2 - matrix->r1c2 * matrix->r2c1;
}

inline double matrix2x2_get_determinant_fp64(const matrix2x2_fp64_t* matrix)
{
    return matrix->r1c1 * matrix->r2c2 - matrix->r1c2 * matrix->r2c1;
}

// ================== Singular ================== //

inline int matrix2x2_is_singular_fp32(const matrix2x2_fp32_t* matrix)
{
    const float determinant = matrix2x2_get_determinant_fp32(matrix);

    return -FP32_EPSYLON <= determinant && determinant <= FP32_EPSYLON;
}

inline int matrix2x2_is_singular_fp64(const matrix2x2_fp64_t* matrix)
{
    const double determinant = matrix2x2_get_determinant_fp64(matrix);

    return -FP64_EPSYLON <= determinant && determinant <= FP64_EPSYLON;
}

// =============== Transposition ================ //

inline void matrix2x2_transpose_fp32(matrix2x2_fp32_t* matrix)
{
    const float tmp = matrix->r1c2;
    matrix->r1c2 = matrix->r2c1;
    matrix->r2c1 = tmp;
}

inline void matrix2x2_transpose_fp64(matrix2x2_fp64_t* matrix)
{
    const double tmp = matrix->r1c2;
    matrix->r1c2 = matrix->r2c1;
    matrix->r2c1 = tmp;
}

// ================= Inversion ================== //

inline int matrix2x2_invert_fp32(matrix2x2_fp32_t* matrix)
{
    const float determinant = matrix2x2_get_determinant_fp32(matrix);

    if (-FP32_EPSYLON <= determinant && determinant <= FP32_EPSYLON) {
        return 0;
    }

    const float r1c1 = matrix->r2c2;
    const float r1c2 = -matrix->r1c2;

    const float r2c1 = -matrix->r2c1;
    const float r2c2 = matrix->r1c1;

    const float multiplier = 1.0f / determinant;

    matrix->r1c1 = r1c1 * multiplier;
    matrix->r1c2 = r1c2 * multiplier;

    matrix->r2c1 = r2c1 * multiplier;
    matrix->r2c2 = r2c2 * multiplier;

    return 1;
}

inline int matrix2x2_invert_fp64(matrix2x2_fp64_t* matrix)
{
    const double determinant = matrix2x2_get_determinant_fp64(matrix);

    if (-FP64_EPSYLON <= determinant && determinant <= FP64_EPSYLON) {
        return 0;
    }

    const double r1c1 = matrix->r2c2;
    const double r1c2 = -matrix->r1c2;

    const double r2c1 = -matrix->r2c1;
    const double r2c2 = matrix->r1c1;

    const double multiplier = 1.0 / determinant;

    matrix->r1c1 = r1c1 * multiplier;
    matrix->r1c2 = r1c2 * multiplier;

    matrix->r2c1 = r2c1 * multiplier;
    matrix->r2c2 = r2c2 * multiplier;

    return 1;
}

// =============== Set Transposed =============== //

inline void matrix2x2_set_transposed_fp32(const matrix2x2_fp32_t* from, matrix2x2_fp32_t* to)
{
    float tmp = from->r1c2;

    to->r1c1 = from->r1c1;
    to->r1c2 = from->r2c1;

    to->r2c1 = tmp;
    to->r2c2 = from->r2c2;
}

inline void matrix2x2_set_transposed_fp64(const matrix2x2_fp64_t* from, matrix2x2_fp64_t* to)
{
    double tmp = from->r1c2;

    to->r1c1 = from->r1c1;
    to->r1c2 = from->r2c1;

    to->r2c1 = tmp;
    to->r2c2 = from->r2c2;
}

// ================ Set Inverted ================ //

inline int matrix2x2_set_inverted_fp32(const matrix2x2_fp32_t* from, matrix2x2_fp32_t* to)
{
    const float determinant = matrix2x2_get_determinant_fp32(from);

    if (-FP32_EPSYLON <= determinant && determinant <= FP32_EPSYLON) {
        return 0;
    }

    const float r1c1 = from->r2c2;
    const float r1c2 = -from->r1c2;

    const float r2c1 = -from->r2c1;
    const float r2c2 = from->r1c1;

    const float multiplier = 1.0f / determinant;

    to->r1c1 = r1c1 * multiplier;
    to->r1c2 = r1c2 * multiplier;

    to->r2c1 = r2c1 * multiplier;
    to->r2c2 = r2c2 * multiplier;

    return 1;
}

inline int matrix2x2_set_inverted_fp64(const matrix2x2_fp64_t* from, matrix2x2_fp64_t* to)
{
    const double determinant = matrix2x2_get_determinant_fp64(from);

    if (-FP64_EPSYLON <= determinant && determinant <= FP64_EPSYLON) {
        return 0;
    }

    const double r1c1 = from->r2c2;
    const double r1c2 = -from->r1c2;

    const double r2c1 = -from->r2c1;
    const double r2c2 = from->r1c1;

    const double multiplier = 1.0 / determinant;

    to->r1c1 = r1c1 * multiplier;
    to->r1c2 = r1c2 * multiplier;

    to->r2c1 = r2c1 * multiplier;
    to->r2c2 = r2c2 * multiplier;

    return 1;
}

// ================= Set Row 1 ================== //

inline void matrix2x2_set_row1_fp32(const float c1, const float c2, matrix2x2_fp32_t* matrix)
{
    matrix->r1c1 = c1;
    matrix->r1c2 = c2;
}

inline void matrix2x2_set_row1_fp64(const double c1, const double c2, matrix2x2_fp64_t* matrix)
{
    matrix->r1c1 = c1;
    matrix->r1c2 = c2;
}

// ================= Set Row 2 ================== //

inline void matrix2x2_set_row2_fp32(const float c1, const float c2, matrix2x2_fp32_t* matrix)
{
    matrix->r2c1 = c1;
    matrix->r2c2 = c2;
}

inline void matrix2x2_set_row2_fp64(const double c1, const double c2, matrix2x2_fp64_t* matrix)
{
    matrix->r2c1 = c1;
    matrix->r2c2 = c2;
}

// ================ Set Column 1 ================ //

inline void matrix2x2_set_column1_fp32(const float r1, const float r2, matrix2x2_fp32_t* matrix)
{
    matrix->r1c1 = r1;
    matrix->r2c1 = r2;
}

inline void matrix2x2_set_column1_fp64(const double r1, const double r2, matrix2x2_fp64_t* matrix)
{
    matrix->r1c1 = r1;
    matrix->r2c1 = r2;
}

// ================ Set Column 2 ================ //

inline void matrix2x2_set_column2_fp32(const float r1, const float r2, matrix2x2_fp32_t* matrix)
{
    matrix->r1c2 = r1;
    matrix->r2c2 = r2;
}

inline void matrix2x2_set_column2_fp64(const double r1, const double r2, matrix2x2_fp64_t* matrix)
{
    matrix->r1c2 = r1;
    matrix->r2c2 = r2;
}

// ================ Append scaled =============== //

inline void matrix2x2_add_scaled_fp32(matrix2x2_fp32_t* basic_vector, const matrix2x2_fp32_t* scalable_vector, const float scale)
{
    basic_vector->r1c1 += scalable_vector->r1c1 * scale;
    basic_vector->r1c2 += scalable_vector->r1c2 * scale;

    basic_vector->r2c1 += scalable_vector->r2c1 * scale;
    basic_vector->r2c2 += scalable_vector->r2c2 * scale;
}

inline void matrix2x2_add_scaled_fp64(matrix2x2_fp64_t* basic_vector, const matrix2x2_fp64_t* scalable_vector, const double scale)
{
    basic_vector->r1c1 += scalable_vector->r1c1 * scale;
    basic_vector->r1c2 += scalable_vector->r1c2 * scale;

    basic_vector->r2c1 += scalable_vector->r2c1 * scale;
    basic_vector->r2c2 += scalable_vector->r2c2 * scale;
}

// ================== Addition ================== //

inline void matrix2x2_add_fp32(const matrix2x2_fp32_t* matrix1, const matrix2x2_fp32_t* matrix2, matrix2x2_fp32_t* sum)
{
    sum->r1c1 = matrix1->r1c1 + matrix2->r1c1;
    sum->r1c2 = matrix1->r1c2 + matrix2->r1c2;

    sum->r2c1 = matrix1->r2c1 + matrix2->r2c1;
    sum->r2c2 = matrix1->r2c2 + matrix2->r2c2;
}

inline void matrix2x2_add_fp64(const matrix2x2_fp64_t* matrix1, const matrix2x2_fp64_t* matrix2, matrix2x2_fp64_t* sum)
{
    sum->r1c1 = matrix1->r1c1 + matrix2->r1c1;
    sum->r1c2 = matrix1->r1c2 + matrix2->r1c2;

    sum->r2c1 = matrix1->r2c1 + matrix2->r2c1;
    sum->r2c2 = matrix1->r2c2 + matrix2->r2c2;
}

// ================ Subtraction ================= //

inline void matrix2x2_subtract_fp32(const matrix2x2_fp32_t* minuend, const matrix2x2_fp32_t* subtrahend, matrix2x2_fp32_t* difference)
{
    difference->r1c1 = minuend->r1c1 - subtrahend->r1c1;
    difference->r1c2 = minuend->r1c2 - subtrahend->r1c2;

    difference->r2c1 = minuend->r2c1 - subtrahend->r2c1;
    difference->r2c2 = minuend->r2c2 - subtrahend->r2c2;
}

inline void matrix2x2_subtract_fp64(const matrix2x2_fp64_t* minuend, const matrix2x2_fp64_t* subtrahend, matrix2x2_fp64_t* difference)
{
    difference->r1c1 = minuend->r1c1 - subtrahend->r1c1;
    difference->r1c2 = minuend->r1c2 - subtrahend->r1c2;

    difference->r2c1 = minuend->r2c1 - subtrahend->r2c1;
    difference->r2c2 = minuend->r2c2 - subtrahend->r2c2;
}

// =============== Multiplication =============== //

inline void matrix2x2_multiply_fp32(const matrix2x2_fp32_t* multiplicand, const float multiplier, matrix2x2_fp32_t* product)
{
    product->r1c1 = multiplicand->r1c1 * multiplier;
    product->r1c2 = multiplicand->r1c2 * multiplier;

    product->r2c1 = multiplicand->r2c1 * multiplier;
    product->r2c2 = multiplicand->r2c2 * multiplier;
}

inline void matrix2x2_multiply_fp64(const matrix2x2_fp64_t* multiplicand, const double multiplier, matrix2x2_fp64_t* product)
{
    product->r1c1 = multiplicand->r1c1 * multiplier;
    product->r1c2 = multiplicand->r1c2 * multiplier;

    product->r2c1 = multiplicand->r2c1 * multiplier;
    product->r2c2 = multiplicand->r2c2 * multiplier;
}

// ================== Division ================== //

inline void matrix2x2_divide_fp32(const matrix2x2_fp32_t* dividend, const float divisor, matrix2x2_fp32_t* quotient)
{
    matrix2x2_multiply_fp32(dividend, 1.0f / divisor, quotient);
}

inline void matrix2x2_fp64_divide(const matrix2x2_fp64_t* dividend, const double divisor, matrix2x2_fp64_t* quotient)
{
    matrix2x2_multiply_fp64(dividend, 1.0 / divisor, quotient);
}

// ============ Left Vector Product ============= //

inline void matrix2x2_left_product_fp32(const vector2_fp32_t* vector, const matrix2x2_fp32_t* matrix, vector2_fp32_t* result)
{
    const float x1 = vector->x1 * matrix->r1c1 + vector->x2 * matrix->r2c1;
    const float x2 = vector->x1 * matrix->r1c2 + vector->x2 * matrix->r2c2;

    result->x1 = x1;
    result->x2 = x2;
}

inline void matrix2x2_left_product_fp64(const vector2_fp64_t* vector, const matrix2x2_fp64_t* matrix, vector2_fp64_t* result)
{
    const double x1 = vector->x1 * matrix->r1c1 + vector->x2 * matrix->r2c1;
    const double x2 = vector->x1 * matrix->r1c2 + vector->x2 * matrix->r2c2;

    result->x1 = x1;
    result->x2 = x2;
}

// ============ Right Vector Product ============ //

inline void matrix2x2_right_product_fp32(const matrix2x2_fp32_t* matrix, const vector2_fp32_t* vector, vector2_fp32_t* result)
{
    const float x1 = matrix->r1c1 * vector->x1 + matrix->r1c2 * vector->x2;
    const float x2 = matrix->r2c1 * vector->x1 + matrix->r2c2 * vector->x2;

    result->x1 = x1;
    result->x2 = x2;
}

inline void matrix2x2_right_product_fp64(const matrix2x2_fp64_t* matrix, const vector2_fp64_t* vector, vector2_fp64_t* result)
{
    const double x1 = matrix->r1c1 * vector->x1 + matrix->r1c2 * vector->x2;
    const double x2 = matrix->r2c1 * vector->x1 + matrix->r2c2 * vector->x2;

    result->x1 = x1;
    result->x2 = x2;
}

#endif