#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/cursorfont.h>
// #include "gs.xpm"

Display *display;
Window win, child, root;
XEvent event;
GC gc, gc2;
int screen,
    depth,
    white,
    black,
    x = 0,
    y  = 0,
    x1 = 0,
    y1 = 0,
    get = 0,
    tx = 10,
    ty = 100,
    cursor = 0,
    a = 0,
    i;
Cursor pencil;
KeySym key;
XFontStruct *font;
XTextProperty title;
Pixmap pixmap;
XColor color;
Colormap colormap;
char keyc[100], *thetitle = "char *thetitle = \"char *the...";

int returncolor(int r, int g, int b);

int main(int argc, char *argv[]) {
  
  cursor = 86;
  memset(keyc, 0, sizeof(keyc));
  display = XOpenDisplay(getenv("DISPLAY"));
  if (!display) {
    fprintf(stderr, "%s: unable to open display %s\n", argv[0], getenv("DISPLAY"));
    return 1;
  } else printf("%s: running on display %s\n", argv[0], getenv("DISPLAY"));

  screen = DefaultScreen(display);
  root = RootWindow(display, screen);
  colormap = DefaultColormap(display, screen);
  depth = DefaultDepth(display, screen);
  white = WhitePixel(display, screen);
  black = BlackPixel(display, screen);

  win = XCreateSimpleWindow(display, root, 0, 0, 320, 240, 0, white, returncolor(0xaaaa, 0xaaaa, 0xaaaa));
  child = XCreateSimpleWindow(display, win, 0, 0, 100, 100, 0, white, white);

  gc = XCreateGC(display, win, 0, 0);
  gc2 = XCreateGC(display, child, 0, 0);
  XSetForeground(display, gc, black);
  XSetForeground(display, gc2, black);
  XStringListToTextProperty(&thetitle, 1, &title);
  XSetWMName(display, win, &title); 
  font = XLoadQueryFont(display, "*helveti*med*-r*12*");
  if (!font) perror("XLoadQueryFont");
  XSetFont(display, gc, font->fid);
  pencil = XCreateFontCursor(display, cursor);
  XDefineCursor(display, win, pencil);

  pixmap = XCreatePixmap(display, root, 45, 45, depth);

  XSelectInput(display, win, ExposureMask | ButtonPressMask | ButtonMotionMask | KeyPressMask);
  XSelectInput(display, child, ButtonPressMask);
  XMapWindow(display, win);

//  XGrabKeyboard(display, root, False, GrabModeAsync, GrabModeAsync, CurrentTime);
//  XGrabPointer(display, root, False, ButtonPressMask | ButtonReleaseMask, GrabModeAsync, GrabModeAsync, root, None, CurrentTime);
//  sleep(5);
//  XAllowEvents(display, AsyncPointer, CurrentTime);
//  printf("pointer freeed\n");
//  sleep(5);

  XGrabServer(display);
  sleep(10);
  exit(1);

  while (1) {
    XNextEvent(display, &event);
    switch(event.type) {
    case Expose:
      if (event.xexpose.count > 0) break;
      XDrawLine(display, win, gc, 0, 0, 100, 100);
      XDrawLine(display, win, gc, 100, 0, 0, 100);
      break;
    case ButtonPress: // XDrawPoint(display, win, gc, event.xbutton.x, event.xbutton.y);
      // XDrawString(display, win, gc, 0, 0, "hello world", strlen("hello world"));

      if (event.xbutton.window == child) return 0;
      if (event.xbutton.state == ShiftMask) XDrawLine(display, win, gc, 
                    event.xbutton.x,
                    event.xbutton.y,
                    x1, y1);
      if (event.xbutton.button == Button3) exit(0);
      x = event.xbutton.x;
      y = event.xbutton.y;
      x1 = x;
      y1 = y;
      break;
    case MotionNotify:  //XDrawPoint(display, win, gc, event.xmotion.x, event.xmotion.y);
      if (get == 0) {
        x = event.xmotion.x;
        y = event.xmotion.y;
        get = 1;
      } else if (get == 1) {
        x1 = event.xmotion.x;
        y1 = event.xmotion.y;
        get = 0;
      }

      XDrawLine(display, win, gc, x, y, x1, y1);
      break;

    case KeyPress:
      key = XKeycodeToKeysym(display, event.xkey.keycode, 0);
      if (key == 65293) {
        ty += 10;
        tx = 10;
      }
      if (key == 65288) tx -= a;

      printf("%d\n", key);
      if ((key > 32 && key < key) || (key > 159))
        break;
      else sprintf(keyc, "%c", key);
      XDrawString(display, win, gc, tx, ty, keyc, strlen(keyc));
      a = XTextWidth(font, keyc, strlen(keyc));
      tx += a;

      switch(key) {
        case '1': XMapWindow(display, child);
            break;
        case '2': XUnmapWindow(display, child);
            break;
        case '3': XSetForeground(display, gc, returncolor(0xffff, 0x0000, 0x0000) );
            break;
        case '4': XSetForeground(display, gc, returncolor(0x0000, 0xffff, 0x0000));
            break;
        case '5': XSetForeground(display, gc, returncolor(0x0000, 0x0000, 0xffff));
            break;
        case '6': XSetForeground(display, gc, returncolor(0x0000, 0xffff, 0xffff));
            break;
        case '7': XSetForeground(display, gc, returncolor(0xffff, 0xffff, 0xffff));
            break;
      }
      break; 
    }
  }

  XFlush(display);
  XCloseDisplay(display);

  return 0;
}

int returncolor(int r, int g, int b) {

  color.red = r;
  color.green = g;
  color.blue = b;

  XAllocColor(display, colormap, &color);
  return  (color.pixel);
}