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

#define VERSION "1.1"
#define ERROR_MSG(msg) fprintf(stderr, "error: "msg"\n")
#define HELPMSG printf("skomb is a program that returns the possible combinations for a given number and cells it spans in a sudoku killer board\nthis current version only supports numbers in the same column or line, or in the same 9x9, although this may change in future versions\nusage: skomb\n       skomb [-h|--help] shows this message\n       skomb [-v|--version]  shows version number\n")

int main(int argc, char **argv){
  if (argc >= 2 && (strcmp(argv[1], "-v") == 0 || strcmp(argv[1], "--version") == 0)){
    printf(VERSION"\n");
    return 0;
  }
  if (argc >= 2 && (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0)){
    HELPMSG;
    return 0;
  }
  while (1){
    printf("Insert number to solve for > ");
    /* number can only be two digits at most + space for null character */
    char *numberc = malloc(sizeof(char) * 3);
    readline(numberc, 3);
    if (numberc[0] == '\0'){
      free(numberc);
      break;
    }
    int number = atoi(numberc);
    free(numberc);
    /* cells can only be one digit at most + space for null character */
    printf("Insert cells it takes up > ");
    char *cellsc = malloc(sizeof(char) * 2);
    readline(cellsc, 2);
    int cells = atoi(cellsc);
    free(cellsc);
    printf("Insert numbers that can't be in the group separated by spaces > ");
    char *not_allowedc = malloc(sizeof(char) * 20);
    readline(not_allowedc, 20);
    int *not_allowed = malloc(sizeof(int) * 9);
    int *not_allowed_len = malloc(sizeof(int)*1);
    *not_allowed_len = splitc_toi(not_allowedc, ' ', not_allowed);
    free(not_allowedc);
    switch (cells){
      case 2:
        if (number >= 3 && number <= 17){
          pair *pairs = malloc(sizeof(pair) * 4);
          int len = perm2(number, not_allowed, not_allowed_len, pairs);
          printf("%d:\n", number);
          for (int i = 0; i < len; i++){
            printf("\t%d + %d\n", pairs[i].x, pairs[i].y);
          }
          free(pairs);
          break;
        }
        ERROR_MSG("number too small or big for ammount of cells");
        free(not_allowed);
        free(not_allowed_len);
        return 3;
      case 3:
        if (number >= 6 && number <= 24){
          trio *trios = malloc(sizeof(trio) * 9);
          int len = perm3(number, not_allowed, not_allowed_len, trios);
          printf("%d:\n", number);
          for (int i = 0; i < len; i++){
            printf("\t%d + %d + %d\n", trios[i].x, trios[i].y, trios[i].z);
          }
          free(trios);
          break;
        }
        ERROR_MSG("number too small or big for ammount of cells");
        free(not_allowed);
        free(not_allowed_len);
        return 3;
      case 4:
        if (number >= 10 && number <= 30){
          quartet *quartets = malloc(sizeof(quartet) * 12);
          int len = perm4(number, not_allowed, not_allowed_len, quartets);
          printf("%d:\n", number);
          for (int i = 0; i < len; i++){
            printf("\t%d + %d + %d + %d\n", quartets[i].x, quartets[i].y, quartets[i].z, quartets[i].w);
          }
          free(quartets);
          break;
        }
        ERROR_MSG("number too small or big for ammount of cells");
        free(not_allowed);
        free(not_allowed_len);
        return 3;
      case 5:
        if (number >= 15 && number <= 35){
          quintet *quintets = malloc(sizeof(quintet) * 12);
          int len = perm5(number, not_allowed, not_allowed_len, quintets);
          printf("%d:\n", number);
          for (int i = 0; i < len; i++){
            printf("\t%d + %d + %d + %d + %d\n", quintets[i].x, quintets[i].y, quintets[i].z, quintets[i].w, quintets[i].v);
          }
          free(quintets);
          break;
        }
        ERROR_MSG("number too small or big for ammount of cells");
        free(not_allowed);
        free(not_allowed_len);
        return 3;
      default:
        ERROR_MSG("invalid ammount of cells");
        free(not_allowed);
        free(not_allowed_len);
        HELPMSG;
        return 4;
    }
    free(not_allowed);
    free(not_allowed_len);
  }
  return 0;
}