#include "matrix.h"
#include <stdlib.h>

// Matrix erstellen
Matrix createMatrix(unsigned int rows, unsigned int cols)
{
    Matrix m;
    if (rows == 0 || cols == 0) {
        m.rows = 0;
        m.cols = 0;
        m.buffer = NULL;
        return m;
    }

    m.rows = rows;
    m.cols = cols;
    m.buffer = (MatrixType*)calloc(rows * cols, sizeof(MatrixType));
    if (!m.buffer) {
        m.rows = 0;
        m.cols = 0;
    }
    return m;
}

// Speicher freigeben
void clearMatrix(Matrix *matrix)
{
    if (!matrix || !matrix->buffer) return;
    free(matrix->buffer);
    matrix->buffer = NULL;
    matrix->rows = 0;
    matrix->cols = 0;
}

// Wert setzen
void setMatrixAt(MatrixType value, Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
{
    if (rowIdx >= matrix.rows || colIdx >= matrix.cols) return;
    matrix.buffer[rowIdx * matrix.cols + colIdx] = value;
}

// Wert auslesen
MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
{
    if (rowIdx >= matrix.rows || colIdx >= matrix.cols) return UNDEFINED_MATRIX_VALUE;
    return matrix.buffer[rowIdx * matrix.cols + colIdx];
}

// Addition
Matrix add(const Matrix matrix1, const Matrix matrix2)
{
    Matrix result;
    if (matrix1.rows != matrix2.rows || matrix1.cols != matrix2.cols) {
        result.rows = 0;
        result.cols = 0;
        result.buffer = NULL;
        return result;
    }

    result = createMatrix(matrix1.rows, matrix1.cols);
    for (unsigned int i = 0; i < matrix1.rows * matrix1.cols; i++)
        result.buffer[i] = matrix1.buffer[i] + matrix2.buffer[i];

    return result;
}

// Multiplikation
Matrix multiply(const Matrix matrix1, const Matrix matrix2)
{
    Matrix result;
    if (matrix1.cols != matrix2.rows) {
        result.rows = 0;
        result.cols = 0;
        result.buffer = NULL;
        return result;
    }

    result = createMatrix(matrix1.rows, matrix2.cols);

    for (unsigned int i = 0; i < matrix1.rows; i++)
    {
        for (unsigned int j = 0; j < matrix2.cols; j++)
        {
            MatrixType sum = 0;
            for (unsigned int k = 0; k < matrix1.cols; k++)
                sum += matrix1.buffer[i * matrix1.cols + k] * matrix2.buffer[k * matrix2.cols + j];
            result.buffer[i * result.cols + j] = sum;
        }
    }

    return result;
}