/* getPuzzle.c
 *
 * finds the puzzle board on the image and outputs the puzzle image
 *
 * Input: one GrayImage
 *
 * 
 * by Victor A. Dan, Dan Knights, Laura Matefy  ****   for CX 336 Project
 */


static char usage[] = "usage:\n %s inputPuzzleBigImage\n"; 


#include <stdio.h>
#include <limits.h> /* for INT_MAX */
#include <getopt.h>
#include <math.h>
#include "mcimg.h"

/* comment out for speed later! */
#define IMAGE_CHECKALL
#define thresh 60
#define err 7 
/*the boundaries of the initial image may contain some black pixles - 
  to avoid them we should start with the scan lines a bit further*/
#define threshH 200
#define mean 10 
int findX1(GrayImage im){
  int x =err, y=0, i;
  int siz=0, X[1000]={0}, Sum=0;
  int width = imGetWidth(im);
  int height = imGetHeight(im);
  if(height/2>mean)
    {
      for(y=height/2-mean; y<height/2+mean; y++)
	{
	  while(imRef(im, x, y)>thresh && x < width-1){
	    
	    x++;
	  }
	  X[siz]=x;
	  siz++;
	}
      for(i=0; i<2*mean; i++)
	Sum=Sum+X[i];
      //fprintf(stderr, "%d, %d\n", Sum/mean, siz);
      return Sum/(2*mean);
    }
  else
    return 0;
}
int findY1(GrayImage im){
  int x =err, y=0, i;
  int siz=0, Y[1000]={0}, Sum=0;
  int width = imGetWidth(im);
  int height = imGetHeight(im);
  if(width/2>mean)
    {
      for(x=width/2-mean; x<width/2+mean; x++)
	{
	  while(imRef(im, x, y)>thresh && y<height-1){
	    printf("%d\n", y);
	    y++;
	  }
	  Y[siz]=y;
	  siz++;
	}
      for(i=0; i<2*mean; i++)
	Sum=Sum+Y[i];
      //fprintf(stderr, "%d, %d\n", Sum/mean, siz);
      return Sum/(2*mean);
    }
  else
    return 0;
}
int findX2(GrayImage im){
  int x =0, y=0, i;
  int siz=0, X1[1000]={0}, Sum=0;
  int width = imGetWidth(im);
  int height = imGetHeight(im);
  x=width-1;
  if(height/2>mean)
    {
      for(y=height/2-mean; y<height/2+mean; y++)
	{
	  while(imRef(im, x, y)>thresh && x>=0){
	    
	    x--;
	  }
	  X1[siz]=x;
	  siz++;
	}
      for(i=0; i<2*mean; i++)
	Sum=Sum+X1[i];
      //fprintf(stderr, "%d, %d\n", Sum/mean, siz);
      return Sum/(2*mean);
    }
  else
    return 0;
}
int length(int X1, int X2){
  return ABS(X2-X1);
}
int main(int argc, char **argv)
{
  char *im1name;
  GrayImage im1, out;
  int width, X1, Y1, X2, i, j, argnum=1, width1, height1; 
  if (argc!= 2) {
    fprintf(stderr, usage, argv[0]);
    exit(1);
  }
  im1name = argv[argnum++];
  
  im1 = loadGrayImage(im1name);
  width1 = imGetWidth(im1);
  height1 = imGetHeight(im1);
  X1=findX1(im1);
  Y1=findY1(im1);
  
  X2=findX2(im1);
  width = length(X1, X2);
  if(width <=0)
    exit(0);
  else
    {
      out = newGrayImage(width, width);
      for(j=0; j<width; j++)
	for(i=0; i<width; i++)
	  if(X1+i<width1 && Y1+j < height1)
	    imRef(out, i, j)=imRef(im1, X1+i, Y1+j);
      //fprintf(stderr, "I'm running\n");
      saveGrayImage(out, "puzzle.pgm");
      
      imFree(out);
    }
  return(0);
}