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

// TODO Matrix-Funktionen implementieren

typedef struct Matrix {
    unsigned int rows;
    unsigned int cols;
    MatrixType* buffer;
} Matrix;


Matrix createMatrix(unsigned int rows, unsigned int cols)
{
    Matrix newMatrix;
	newMatrix.rows = rows;
	newMatrix.cols = cols;
	newMatrix.buffer = calloc(rows*cols, sizeof(MatrixType));
	return newMatrix;
}

void clearMatrix(Matrix *matrix)
{
    free(matrix->buffer);
	matrix->buffer = NULL;
}

void setMatrixAt(MatrixType value, Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
{
    if (rowIdx >= matrix.rows || colIdx >= matrix.cols){
        printf("Index out of bounds\n"); //Error Message because Index Input exceeds Matrix
}
    else{
        matrix.buffer[rowIdx * matrix.cols + colIdx] = value; //Writes Value of value variable in the selected place in Matrix
}
}

MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
{
    if (rowIdx >= matrix.rows || colIdx >= matrix.cols){
       printf("Index out of bounds\n");
       return 0;
    }
    else{

       MatrixType value = matrix.buffer[rowIdx * matrix.cols + colIdx]; //Stores value of selected place of Matrix in value variable
        return value;
}
  }

Matrix add(const Matrix matrix1, const Matrix matrix2)
{
    Matrix MatrixErgebnis = createMatrix(matrix1.rows, matrix1.cols); //Creating Result Matrix
    if(matrix1.cols != matrix2.cols || matrix1.rows != matrix2.rows){
        printf("Matrix dimensions do not match\n"); //Error Message if dimensions of Input Matrixes are not identical
        clearMatrix(&MatrixErgebnis);
        return MatrixErgebnis;
    }
    else{

        for (unsigned int i = 0; i < matrix1.rows; i++){
            for (unsigned int j = 0; j < matrix1.cols; j++){
                //Adding Matrix Elements of same row and col index together and store in new Matrix
                MatrixErgebnis.buffer[i * matrix1.cols + j] = matrix1.buffer[i * matrix1.cols + j] + matrix2.buffer[i * matrix1.cols + j];

                }
        }

  }
return MatrixErgebnis;
}

Matrix multiply(const Matrix matrix1, const Matrix matrix2)
{

    Matrix result;
    result.rows = matrix1.rows;
    result.cols = matrix2.cols;

    if (matrix1.rows == matrix2.cols) {

        result.buffer = malloc(result.rows * result.cols * sizeof(MatrixType));

        for(int i = 0; i < result.rows; i++) {
            for(int j = 0; j < result.cols; j++) {
                MatrixType value = 0;
                for(int k = 0; k < matrix1.cols; k++) {
                    value += matrix1.buffer[i * matrix1.cols + k] * matrix2.buffer[k * matrix2.cols + j];
                }
                result.buffer[i * matrix1.cols + j] = value;
            }
        }
        return result;
    }
    printf("Die angegebenen Matrizen haben keine passenden Dimensionen für die Multiplikation");
    return result;
}