#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
int r1 = 1,c1 = 1,r2 = 1,c2 = 1;
float** matrix2;
float** matrix1;
int no_threads = 0;



struct  thread_data
{
    int row ,column; //position of element that the thread will calculate
    float ** mult_matrix;
}thread_data;
void get_sizes(char ** file_name,int * r ,int * c)
{
    //getting number of columns and rows
    int flag = 0 ;
    FILE *f;
    f = fopen(file_name,"r");
    if(f != NULL )
    {
         while (!feof(f))
    {
        char ch = fgetc(f);
       if(ch == ' ' && flag == 0)
       {
           *c = *c + 1 ;

       }

       if(ch == '\n')
      {
          *r = *r + 1 ;
          flag = 1; //flag to stop counting spaces

      }
    }

    fclose(f);
    }
    else
  {
      printf("error reading file");
      exit(-1);
  }



}
float ** build_matrix(char ** file_name,int * r ,int * c )
{
  FILE *f;
  float temp[50];
   int rows = *r , columns = *c;
  int counter = 0,i = 0,j = 0;
  //dynamic allocation for matrix
  float **matrix;
    matrix = malloc(sizeof(float*) * columns);

    for(i = 0; i < rows; i++) {
        matrix[i] = malloc(sizeof(float*) * columns);
    }

    //getting the values in a temporary array
  f = fopen(file_name, "r");
  if(f != NULL )
  {
      while (!feof(f))
    {

      fscanf(f,"%f",&temp[counter]);

      counter++;
    }

    // building the matrix

        counter = 0 ;
        for(i = 0; i < *r; i++)
        {

            for(j = 0; j < *c; j++)
            {
                matrix[i][j] = temp[counter];
                counter++;
            }

        }

  }
  else
  {
      printf("error reading file");
      exit(-1);
  }



  fclose(f);
  return matrix;

}


void threadedMatMultPerElement(void *s)
{
    //row and column of cell to be calculated and limits to loops
    int row = ((struct thread_data *)s)->row;
    int column = ((struct thread_data *)s)->column;
    int sum = 0;
    float ** mult_matrix = ((struct thread_data *)s)->mult_matrix;
    for (int i = 0; i < c1 ;i++)
    {

        sum  = sum + matrix1[row][i] * matrix2[i][column];

    }

    mult_matrix[row][column] = sum;
    no_threads++;

}
void print_matrix(int r,int c,float ** matrix)
{
    for(int i = 0; i < r; i++)
        {
            for(int j = 0; j < c; j++)
            {
                printf("%.4f ",matrix[i][j]);

            }
            printf("\n");
        }
}


int main(int argc, char *argv[])
{

     float temp[50];
     char file_name[25];
     pthread_t threads[r1*c2];

    //getting the 2 matrices
    printf("enter the first matrix file name :  ");
  scanf("%s",file_name);
  get_sizes(file_name,&r1,&c1);

  matrix1 = build_matrix(file_name,&r1,&c1);
  //print_matrix(r1,c1,matrix1);
  //getting second matrix

  printf("enter the second matrix file name :  ");
  scanf("%s",file_name);
  get_sizes(file_name,&r2,&c2);

  matrix2 = build_matrix(file_name,&r2,&c2);
  //print_matrix(r2,c2,matrix2);


  for (int i = 0; i < r1; i++)
    {
        for (int j =0; j< c2; j++)
        {
            struct thread_data *s = (struct thread_data *)malloc(sizeof(struct thread_data));
            s->row = i;
            s->column = j;
            s->mult_matrix = matrix3;
            pthread_create(&threads[i], NULL, threadedMatMultPerElement,s);
        }

    }



    for (int i = 0; i < c2*r1; i++)
    {
      pthread_join(threads[i], NULL);
    }

    print_matrix(r1,c2,matrix3);
return 0;
}