#include "dim.h"

#include <GL/glut.h>
#include <iostream.h>
#include <stdio.h>



int fb[BUFFWIDTH][BUFFHEIGHT];  /* the simulated frame buffer */
int width=500,height=500;  /*  initial window size  */
float pixwidth = (float) width/BUFFWIDTH;  /* simulated pixel width */
float pixheight = (float) height/BUFFHEIGHT;  /* simulated pixel height */
int inline inrange(int i, int low, int high) {return((low <= i) && (i <= high));} 
enum mode {Point, Line};  /* possible modes of program */
mode currmode=Point; /* current point, initially Point */
int vptx0, vptx1, vpty0, vpty1;

void init()
{
  glClearColor(0.0,0.0,0.0,0.0);  /* clear color is black  */
  for (int i=0; i<BUFFWIDTH; i++)  /* initially simulated pixels are black */
    for (int j=0; j<BUFFHEIGHT; j++)
	fb[i][j]=0;

  printf("Enter the coordinates of the lower left and upper right corners of the viewport. (x range: 0-%d, y:range 0-%d.)\n", BUFFWIDTH-1, BUFFHEIGHT-1);
  scanf("%d %d %d %d", &vptx0, &vpty0, &vptx1, &vpty1);
  

}

void display()
{
  glClear(GL_COLOR_BUFFER_BIT);  /* clear the screen */
  glColor3f(1.0,0.0,0.0);  /* viewport is red */
  glRectf((float) vptx0*pixwidth, (float) vpty0*pixheight, (float) vptx1*pixwidth, (float) vpty1*pixheight);

  glColor3f(1.0,1.0,1.0);  /*  drawing color is white */
  for (int i=0;i<BUFFWIDTH;i++)  /* draw the "on"  pixels */
    for (int j=0;j<BUFFHEIGHT;j++)
      if (fb[i][j]==1) 			
	glRectf(i*pixwidth, j* pixheight,(i+1)*pixwidth, (j+1)*pixheight);
  glutSwapBuffers();

}

void reshape(int w, int h)
{
  width = w;
  height = h;
  pixwidth =(float) w/BUFFWIDTH;
  pixheight = (float) h/BUFFHEIGHT;
  glViewport(0,0,w,h);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  glOrtho(0,w,0,h,-1,1);
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
}

void keyboard(unsigned char key, int x, int y)
{
  switch (key) {

  case 'C':  /* clear the simulated frame buffer */
  case 'c': 
    for (int i=0;i<BUFFWIDTH;i++)
      for(int j=0;j<BUFFHEIGHT;j++)
	fb[i][j]=0;
    glutPostRedisplay();
    break;

  case 'P':   /* enter Point mode */
  case 'p':
    currmode = Point;
    glutSetWindowTitle("Z's Points (C=Clear, L=Lines)");
    break;

  case 'L':   /* enter Line mode - MODIFY HERE */
  case 'l':
    currmode = Line;
    glutSetWindowTitle("Z's Lines (C=Clear, P=Points)");
  }
}

void mouse(int button, int state, int x, int y)
{
  if (state == GLUT_DOWN) {
    if (currmode == Point) {  /* toggle chosen pixel */
       int x0 =  x/pixwidth;
       int y0 =  BUFFHEIGHT - y/pixheight; 
       fb[x0][y0]=1-fb[x0][y0];
       glutPostRedisplay();
     }
     else if (currmode == Line) {
       /* DO SOMETHING */
	 }
  }
}





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

  /* set up window */
  glutInit(&argc, argv);
  glutInitDisplayMode(GLUT_DOUBLE |  GLUT_RGB);
  glutInitWindowSize(width,height);
  glutInitWindowPosition(100,100);
  glutCreateWindow("Z's Points (C=Clear, L=Lines)");

  init();  /* initialize program parameters */

  /* register callback functions */
  glutDisplayFunc(display);  
  glutReshapeFunc(reshape);
  glutKeyboardFunc(keyboard);
  glutMouseFunc(mouse);


  glutMainLoop(); /* loop until something happens */


  return 1;
}