/*****************************************************************************\
 * Exercise 8-1: a program that prints a grid from user-entered dimensions
 *
 * Author: Suzi Anvin
 *
 * Purpose: practice using for statements in C
\*****************************************************************************/

#include <stdio.h>

/* setting up loops to draw a line with 'width' groups of spacers 
 * separated by edges */

void draw_line (int width, char edge, char spacer)
{
  int i, j;			/* counters */
  for (i = 0; i < width; i++) {
    putchar(edge);
    for (j = 0; j < 5; j++) {
      putchar(spacer);
    }
  }
  putchar(edge);
  putchar('\n');
}

int main()
{
  char line[50];
  int width = 0;		/* user selected width of grid */
  int height = 0;		/* heigth of grid */
  int i, j;			/* counters */

  /* getting user dimensions for grid */
  for (;;) {
    printf("Enter the size of desired grid (A x B) or q to quit : ");
    fgets(line, sizeof(line), stdin);
    if (line[0] == 'q' || line[0] == 'Q')
      break;
    sscanf(line, "%d %*[^-0-9] %d", &width, &height);
    /* limiting grid size */
    if (width > 12 || width <= 0 || height > 12 || height <= 0 ) { 
      printf("Please enter positive values of 12 or smaller.\n");
      continue;			/* re-input dimensions */
    }
    /* setting up the loop to draw a grid of the specified height, 
     * avoiding the fencepost error by using height + 1 */
    for (i = 0; i < height; i++) {
      draw_line (width, '+', '-');
      for (j = 0; j < 3; j++) {
	draw_line (width, '|', ' ');
      }
    }
    draw_line (width, '+', '-');
  }
  return (0);
}