#ifndef _BASIC_GEOMETRY_MATRIX2X2_H_
#define _BASIC_GEOMETRY_MATRIX2X2_H_

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

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

static inline void fp32_matrix2x2_reset(fp32_matrix2x2_t* matrix)
{
    matrix->r1c1 = 0.0f;
    matrix->r1c2 = 0.0f;
    matrix->r2c1 = 0.0f;
    matrix->r2c2 = 0.0f;
}

static inline void fp64_matrix2x2_reset(fp64_matrix2x2_t* matrix)
{
    matrix->r1c1 = 0.0;
    matrix->r1c2 = 0.0;
    matrix->r2c1 = 0.0;
    matrix->r2c2 = 0.0;
}

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

static inline void fp32_matrix2x2_set_to_identity(fp32_matrix2x2_t* matrix)
{
    matrix->r1c1 = 1.0f;
    matrix->r1c2 = 0.0f;
    matrix->r2c1 = 0.0f;
    matrix->r2c2 = 1.0f;
}

static inline void fp64_matrix2x2_set_to_identity(fp64_matrix2x2_t* matrix)
{
    matrix->r1c1 = 1.0;
    matrix->r1c2 = 0.0;
    matrix->r2c1 = 0.0;
    matrix->r2c2 = 1.0;
}

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

static inline void fp32_matrix2x2_set_to_diagonal(const float d1, const float d2, fp32_matrix2x2_t* matrix)
{
    matrix->r1c1 = d1;
    matrix->r1c2 = 0.0f;
    matrix->r2c1 = 0.0f;
    matrix->r2c2 = d2;
}

static inline void fp64_matrix2x2_set_to_diagonal(const double d1, const double d2, fp64_matrix2x2_t* matrix)
{
    matrix->r1c1 = d1;
    matrix->r1c2 = 0.0;
    matrix->r2c1 = 0.0;
    matrix->r2c2 = d2;
}

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

static inline void fp32_matrix2x2_make_turn(const float angle, const angle_unit_t unit, fp32_matrix2x2_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;
}

static inline void fp64_matrix2x2_make_turn(const double angle, const angle_unit_t unit, fp64_matrix2x2_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 ==================== //

static inline void fp32_matrix2x2_copy(const fp32_matrix2x2_t* from, fp32_matrix2x2_t* to)
{
    to->r1c1 = from->r1c1;
    to->r1c2 = from->r1c2;

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

static inline void fp64_matrix2x2_copy(const fp64_matrix2x2_t* from, fp64_matrix2x2_t* to)
{
    to->r1c1 = from->r1c1;
    to->r1c2 = from->r1c2;

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

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

static inline void fp32_matrix2x2_swap(fp32_matrix2x2_t* matrix1, fp32_matrix2x2_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;
}

static inline void fp64_matrix2x2_swap(fp64_matrix2x2_t* matrix1, fp64_matrix2x2_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 ============== //

static inline void fp32_matrix2x2_set_from_fp64(const fp64_matrix2x2_t* from, fp32_matrix2x2_t* to)
{
    to->r1c1 = (float)from->r1c1;
    to->r1c2 = (float)from->r1c2;

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

static inline void fp64_matrix2x2_set_from_fp32(const fp32_matrix2x2_t* from, fp64_matrix2x2_t* to)
{
    to->r1c1 = from->r1c1;
    to->r1c2 = from->r1c2;

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

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

static inline float fp32_matrix2x2_get_determinant(const fp32_matrix2x2_t* matrix)
{
    return matrix->r1c1 * matrix->r2c2 - matrix->r1c2 * matrix->r2c1;
}

static inline double fp64_matrix2x2_get_determinant(const fp64_matrix2x2_t* matrix)
{
    return matrix->r1c1 * matrix->r2c2 - matrix->r1c2 * matrix->r2c1;
}

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

static inline int fp32_matrix2x2_is_singular(const fp32_matrix2x2_t* matrix)
{
    const float determinant = fp32_matrix2x2_get_determinant(matrix);

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

static inline int fp64_matrix2x2_is_singular(const fp64_matrix2x2_t* matrix)
{
    const double determinant = fp64_matrix2x2_get_determinant(matrix);

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

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

static inline void fp32_matrix2x2_transpose(fp32_matrix2x2_t* matrix)
{
    const float tmp = matrix->r1c2;
    matrix->r1c2 = matrix->r2c1;
    matrix->r2c1 = tmp;
}

static inline void fp64_matrix2x2_transpose(fp64_matrix2x2_t* matrix)
{
    const double tmp = matrix->r1c2;
    matrix->r1c2 = matrix->r2c1;
    matrix->r2c1 = tmp;
}

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

static inline int fp32_matrix2x2_invert(fp32_matrix2x2_t* matrix)
{
    const float determinant = fp32_matrix2x2_get_determinant(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;
}

static inline int fp64_matrix2x2_invert(fp64_matrix2x2_t* matrix)
{
    const double determinant = fp64_matrix2x2_get_determinant(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 =============== //

static inline void fp32_matrix2x2_set_transposed(const fp32_matrix2x2_t* from, fp32_matrix2x2_t* to)
{
    float tmp = from->r1c2;

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

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

static inline void fp64_matrix2x2_set_transposed(const fp64_matrix2x2_t* from, fp64_matrix2x2_t* to)
{
    double tmp = from->r1c2;

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

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

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

static inline int fp32_matrix2x2_set_inverted(const fp32_matrix2x2_t* from, fp32_matrix2x2_t* to)
{
    const float determinant = fp32_matrix2x2_get_determinant(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;
}

static inline int fp64_matrix2x2_set_inverted(const fp64_matrix2x2_t* from, fp64_matrix2x2_t* to)
{
    const double determinant = fp64_matrix2x2_get_determinant(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 ================== //

static inline void fp32_matrix2x2_set_row1(const float c1, const float c2, fp32_matrix2x2_t* matrix)
{
    matrix->r1c1 = c1;
    matrix->r1c2 = c2;
}

static inline void fp64_matrix2x2_set_row1(const double c1, const double c2, fp64_matrix2x2_t* matrix)
{
    matrix->r1c1 = c1;
    matrix->r1c2 = c2;
}

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

static inline void fp32_matrix2x2_set_row2(const float c1, const float c2, fp32_matrix2x2_t* matrix)
{
    matrix->r2c1 = c1;
    matrix->r2c2 = c2;
}

static inline void fp64_matrix2x2_set_row2(const double c1, const double c2, fp64_matrix2x2_t* matrix)
{
    matrix->r2c1 = c1;
    matrix->r2c2 = c2;
}

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

static inline void fp32_matrix2x2_set_column1(const float r1, const float r2, fp32_matrix2x2_t* matrix)
{
    matrix->r1c1 = r1;
    matrix->r2c1 = r2;
}

static inline void fp64_matrix2x2_set_column1(const double r1, const double r2, fp64_matrix2x2_t* matrix)
{
    matrix->r1c1 = r1;
    matrix->r2c1 = r2;
}

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

static inline void fp32_matrix2x2_set_column2(const float r1, const float r2, fp32_matrix2x2_t* matrix)
{
    matrix->r1c2 = r1;
    matrix->r2c2 = r2;
}

static inline void fp64_matrix2x2_set_column2(const double r1, const double r2, fp64_matrix2x2_t* matrix)
{
    matrix->r1c2 = r1;
    matrix->r2c2 = r2;
}

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

static inline void fp32_matrix2x2_append_scaled(fp32_matrix2x2_t* basic_vector, const fp32_matrix2x2_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;
}

static inline void fp64_matrix2x2_append_scaled(fp64_matrix2x2_t* basic_vector, const fp64_matrix2x2_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 ================== //

static inline void fp32_matrix2x2_add(const fp32_matrix2x2_t* matrix1, const fp32_matrix2x2_t* matrix2, fp32_matrix2x2_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;
}

static inline void fp64_matrix2x2_add(const fp64_matrix2x2_t* matrix1, const fp64_matrix2x2_t* matrix2, fp64_matrix2x2_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 ================= //

static inline void fp32_matrix2x2_subtract(const fp32_matrix2x2_t* minuend, const fp32_matrix2x2_t* subtrahend, fp32_matrix2x2_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;
}

static inline void fp64_matrix2x2_subtract(const fp64_matrix2x2_t* minuend, const fp64_matrix2x2_t* subtrahend, fp64_matrix2x2_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 =============== //

static inline void fp32_matrix2x2_multiply(const fp32_matrix2x2_t* multiplicand, const float multiplier, fp32_matrix2x2_t* product)
{
    product->r1c1 = multiplicand->r1c1 * multiplier;
    product->r1c2 = multiplicand->r1c2 * multiplier;

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

static inline void fp64_matrix2x2_multiply(const fp64_matrix2x2_t* multiplicand, const double multiplier, fp64_matrix2x2_t* product)
{
    product->r1c1 = multiplicand->r1c1 * multiplier;
    product->r1c2 = multiplicand->r1c2 * multiplier;

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

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

static inline void fp32_matrix2x2_divide(const fp32_matrix2x2_t* dividend, const float divisor, fp32_matrix2x2_t* quotient)
{
    fp32_matrix2x2_multiply(dividend, 1.0f / divisor, quotient);
}

static inline void fp64_matrix2x2_divide(const fp64_matrix2x2_t* dividend, const double divisor, fp64_matrix2x2_t* quotient)
{
    fp64_matrix2x2_multiply(dividend, 1.0 / divisor, quotient);
}

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

static inline void fp32_matrix2x2_left_product(const fp32_vector2_t* vector, const fp32_matrix2x2_t* matrix, fp32_vector2_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;
}

static inline void fp64_matrix2x2_left_product(const fp64_vector2_t* vector, const fp64_matrix2x2_t* matrix, fp64_vector2_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 ============ //

static inline void fp32_matrix2x2_right_product(const fp32_matrix2x2_t* matrix, const fp32_vector2_t* vector, fp32_vector2_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;
}

static inline void fp64_matrix2x2_right_product(const fp64_matrix2x2_t* matrix, const fp64_vector2_t* vector, fp64_vector2_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