/*
 * wmgr_deco.c: Find out size/offset of window manager's decoration
 *
 * $Id: wmgr_deco.c,v 1.4 1997/03/17 00:09:40 mb Exp mb $
 *
 * Copyright (c) 1996 Martin Buck  <martin-2.buck@student.uni-ulm.de>
 * Read COPYING for more information
 *
 */

#include <stdio.h>
#include <time.h>
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include "misc.h"
#include "wmgr_deco.h"


#define MAX_BORDER 50
#define MAX_REPARENT_DELAY 10


int
wmgr_get_size(Display *dpy, Window tl_win, wmgr_deco_t *wmgr) {
  static const char *atom_names[] = { "__WM_ROOT", "__SWM_ROOT", NULL };
  const char **atom_name;
  Window vroot, wm_win, root, parent, *children, wdummy;
  Atom vroot_atom;
  int nchildren, wm_wf, wm_hf, wm_xf, wm_yf, wf, hf, xf, yf, wm_border, idummy;
  int lb, rb, tb, bb;
  
  /* Try to find a virtual root window by checking the __(S)WM_ROOT-atom (it should contain its
   * window ID), otherwise assume there's no virtual root window
   */
  vroot = None;
  for (atom_name = atom_names; *atom_name; atom_name++) {
    if ((vroot_atom = XInternAtom(dpy, *atom_name, True)) != None) {
      unsigned char *property;
      Atom type;
      int format;
      unsigned long nitems, after;

      if (XGetWindowProperty(dpy, tl_win, vroot_atom, 0, 1, False, XA_WINDOW, &type, &format,
          &nitems, &after, &property) == Success) {
        if (type == XA_WINDOW && format == 32 && nitems == 1 && after == 0) {
          vroot = *((Window*)property);
#ifdef DEBUG_WMGR
          fprintf(stderr, "wmgr_get_size: %s property found, virtual root is 0x%lx\n",
              *atom_name, (unsigned long)vroot);
#endif
          XFree(property);
          break;
        } else {
#ifdef DEBUG_WMGR
          if (type == None) {
            fprintf(stderr, "wmgr_get_size: no %s property found for toplevel window\n",
                *atom_name);
          } else {
            fprintf(stderr, "wmgr_get_size: ignoring bogus %s property\n", *atom_name);
          }
#endif
          XFree(property);
        }
#ifdef DEBUG_WMGR
      } else {
        fprintf(stderr, "wmgr_get_size: XGetWindowProperty(%s) failed\n", *atom_name);
#endif
      }
#ifdef DEBUG_WMGR
    } else {
      fprintf(stderr, "wmgr_get_size: %s atom doesn't exist\n", *atom_name);
#endif
    }
  }
  
  /* Climb up window tree starting at our main window until we hit the (virtual) root window.
   * We assume that the wm's decoration window is a child of the root window.
   */
  wm_win = tl_win;
  while (XQueryTree(dpy, wm_win, &root, &parent, &children, &nchildren)) {
    XFree(children);
    if (parent == root || (vroot != None && parent == vroot))
      break;
    wm_win = parent;
  }
  
  /* If we're still at our main window, it obviously hasn't been reparented, so we give up */
  if (wm_win == tl_win) {
#ifdef DEBUG_WMGR
    fprintf(stderr, "wmgr_get_size: couldn't find wm's decoration window, giving up\n");
#endif
    return WMGR_NODECO;
  }
  
  /* Get size & absolute coordinates of our main window and its decoration window */
  XGetGeometry(dpy, wm_win, &wdummy, &idummy, &idummy, &wm_wf, &wm_hf, &wm_border, &idummy);
  XTranslateCoordinates(dpy, wm_win, root, 0, 0, &wm_xf, &wm_yf, &wdummy);
  XGetGeometry(dpy, tl_win, &wdummy, &idummy, &idummy, &wf, &hf, &idummy, &idummy);
  XTranslateCoordinates(dpy, tl_win, root, 0, 0, &xf, &yf, &wdummy);
  
  /* Calculate decoration-size */
  lb = xf - wm_xf + wm_border;
  tb = yf - wm_yf + wm_border;
  rb = wm_wf - wf - lb + 2 * wm_border;
  bb = wm_hf - hf - tb + 2 * wm_border;
#ifdef DEBUG_WMGR
  fprintf(stderr, "wmgr_get_size: tl_win: 0x%lx wmgr_win: 0x%lx\n"
      "  tl_win_geo: %dx%d+%d+%d wmgr_geo: %dx%d+%d+%d\n"
      "  wm_decoration: %d,%d,%d,%d\n",
      (unsigned long)tl_win, (unsigned long)wm_win,
      wf, hf, xf, yf, wm_wf, wm_hf, wm_xf, wm_yf,
      lb, rb, tb, bb);
#endif

  /* Some sanity checks... */
  if (lb < 0 || lb > MAX_BORDER || rb < 0 || rb > MAX_BORDER || 
      tb < 0 || tb > MAX_BORDER || bb < 0 || bb > MAX_BORDER) {
#ifdef DEBUG_WMGR
    fprintf(stderr, "wmgr_get_size: decoration-size seems to be bogus, giving up\n");
#endif
    return WMGR_BOGUS;
  }
  wmgr->lb = lb;
  wmgr->rb = rb;
  wmgr->tb = tb;
  wmgr->bb = bb;
  return WMGR_OK;
}


void
wmgr_prepare_get_offset(int x, int y, Window win, wmgr_deco_t *wmgr) {
  if (wmgr->orig_set)
    return;
  wmgr->orig_x = x;
  wmgr->orig_y = y;
  wmgr->orig_win = win;
  wmgr->orig_set = time(NULL);
#ifdef DEBUG_WMGR
  fprintf(stderr, "wmgr_prepare_get_offset: origin %d, %d, window 0x%lx, time %lu\n",
      x, y, (unsigned long)win, (unsigned long)wmgr->orig_set);
#endif
}


int
wmgr_get_offset(int x, int y, Window win, wmgr_deco_t *wmgr) {
  if (!wmgr->orig_set || win != wmgr->orig_win)
    return WMGR_ERR;
  if (time(NULL) - wmgr->orig_set > MAX_REPARENT_DELAY) {
#ifdef DEBUG_WMGR
    fprintf(stderr, "wmgr_get_offset: timeout: %lu\n", (unsigned long)time(NULL));
#endif
    return WMGR_TIMEOUT;
  }
  
  wmgr->ofs_x = wmgr->orig_x - x;
  wmgr->ofs_y = wmgr->orig_y - y;
#ifdef DEBUG_WMGR
  fprintf(stderr, "wmgr_get_offset: offset %d,%d\n", wmgr->ofs_x, wmgr->ofs_y);
#endif

  if (wmgr->ofs_x < -MAX_BORDER || wmgr->ofs_x > MAX_BORDER ||
      wmgr->ofs_y < -MAX_BORDER || wmgr->ofs_y > MAX_BORDER) {
#ifdef DEBUG_WMGR
    fprintf(stderr, "wmgr_get_offset: window offset seems to be bogus, giving up\n");
    return WMGR_BOGUS;
#endif
  }
  return WMGR_OK;
}


int
wmgr_inc_ignore_xconfigure(wmgr_deco_t *wmgr) {
  if (!wmgr->orig_set) {
    wmgr->ignore_xconfigure++;
#ifdef DEBUG_WMGR
    fprintf(stderr, "wmgr_inc_ignore_xconfigure: new value: %d\n", wmgr->ignore_xconfigure);
  } else {
    fprintf(stderr, "wmgr_inc_ignore_xconfigure: orig already set\n");
#endif
  }
  return wmgr->ignore_xconfigure;
}


int
wmgr_dec_ignore_xconfigure(wmgr_deco_t *wmgr) {
  if (wmgr->ignore_xconfigure) {
#ifdef DEBUG_WMGR
    fprintf(stderr, "wmgr_dec_ignore_xconfigure: current value: %d\n", wmgr->ignore_xconfigure);
#endif
    return wmgr->ignore_xconfigure--;
  } else {
#ifdef DEBUG_WMGR
    fprintf(stderr, "wmgr_dec_ignore_xconfigure: no events to ignore\n");
#endif
    return 0;
  }
}