/* Metacity Workspaces */

/* 
 * Copyright (C) 2001 Havoc Pennington
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 */

#include "workspace.h"
#include "errors.h"
#include <X11/Xatom.h>

void meta_workspace_queue_calc_showing  (MetaWorkspace *workspace);

static int set_number_of_spaces_hint  (MetaScreen *screen);
static int set_active_space_hint      (MetaScreen *screen);

MetaWorkspace*
meta_workspace_new (MetaScreen *screen)
{
  MetaWorkspace *workspace;

  workspace = g_new (MetaWorkspace, 1);

  workspace->screen = screen;
  workspace->screen->display->workspaces =
    g_list_append (workspace->screen->display->workspaces, workspace);
  workspace->windows = NULL;

  /* This may have something to do with the strut hints
   * eventually
   */
  workspace->workarea.x = 0;
  workspace->workarea.y = 0;
  workspace->workarea.width = WidthOfScreen (screen->xscreen);
  workspace->workarea.height = HeightOfScreen (screen->xscreen);

  /* Update hint for current number of workspaces */
  set_number_of_spaces_hint (screen);
  
  return workspace;
}

void
meta_workspace_free (MetaWorkspace *workspace)
{
  GList *tmp;
  
  tmp = workspace->windows;
  while (tmp != NULL)
    {
      GList *next;
      next = tmp->next;
      /* pop front of list */
      meta_workspace_remove_window (workspace, tmp->data);

      tmp = next;
    }

  g_assert (workspace->windows == NULL);
  
  workspace->screen->display->workspaces =
    g_list_remove (workspace->screen->display->workspaces, workspace);

  g_free (workspace);
}

void
meta_workspace_add_window (MetaWorkspace *workspace,
                           MetaWindow    *window)
{
  g_return_if_fail (!meta_workspace_contains_window (workspace, window));
  
  workspace->windows = g_list_prepend (workspace->windows, window);
  window->workspaces = g_list_prepend (window->workspaces, workspace);

  meta_window_set_current_workspace_hint (window);
  
  meta_window_queue_calc_showing (window);
}

void
meta_workspace_remove_window (MetaWorkspace *workspace,
                              MetaWindow    *window)
{
  g_return_if_fail (meta_workspace_contains_window (workspace, window));

  workspace->windows = g_list_remove (workspace->windows, window);
  window->workspaces = g_list_remove (window->workspaces, workspace);

  meta_window_set_current_workspace_hint (window);
  
  meta_window_queue_calc_showing (window);
}

gboolean
meta_workspace_contains_window (MetaWorkspace *workspace,
                                MetaWindow    *window)
{
  return g_list_find (workspace->windows, window) != NULL;
}

void
meta_workspace_queue_calc_showing  (MetaWorkspace *workspace)
{
  GList *tmp;

  tmp = workspace->windows;
  while (tmp != NULL)
    {
      meta_window_queue_calc_showing (tmp->data);

      tmp = tmp->next;
    }
}

void
meta_workspace_activate (MetaWorkspace *workspace)
{
  MetaWorkspace *old;
  
  meta_verbose ("Activating workspace %d\n",
                meta_workspace_index (workspace));
  
  if (workspace->screen->active_workspace == workspace)
    return;

  old = workspace->screen->active_workspace;
  
  workspace->screen->active_workspace = workspace;

  set_active_space_hint (workspace->screen);
  
  meta_workspace_queue_calc_showing (old);
  meta_workspace_queue_calc_showing (workspace);
}

int
meta_workspace_index (MetaWorkspace *workspace)
{
  GList *tmp;
  int i;

  i = 0;
  tmp = workspace->screen->display->workspaces;
  while (tmp != NULL)
    {
      if (tmp->data == workspace)
        return i;

      ++i;
                    
      tmp = tmp->next;
    }

  meta_bug ("Workspace does not exist to index!\n");
}

int
meta_workspace_screen_index  (MetaWorkspace *workspace)
{
  GList *tmp;
  int i;

  i = 0;
  tmp = workspace->screen->display->workspaces;
  while (tmp != NULL)
    {
      MetaWorkspace *w = tmp->data;

      if (tmp->data == workspace)
        return i;

      if (w->screen == workspace->screen)
        ++i;
                    
      tmp = tmp->next;
    }

  meta_bug ("Workspace does not exist to index!\n");
}

static int
set_number_of_spaces_hint (MetaScreen *screen)
{
  unsigned long data[1];
  
  data[0] = meta_screen_get_n_workspaces (screen);

  meta_verbose ("Setting _NET_NUMBER_OF_DESKTOPS to %ld\n", data[0]);
  
  meta_error_trap_push (screen->display);
  XChangeProperty (screen->display->xdisplay, screen->xroot,
                   screen->display->atom_net_number_of_desktops,
                   XA_CARDINAL,
                   32, PropModeReplace, (guchar*) data, 1);
  return meta_error_trap_pop (screen->display);
}

static int
set_active_space_hint (MetaScreen *screen)
{
  unsigned long data[1];
  
  data[0] = meta_workspace_screen_index (screen->active_workspace);

  meta_verbose ("Setting _NET_CURRENT_DESKTOP to %ld\n", data[0]);
  
  meta_error_trap_push (screen->display);
  XChangeProperty (screen->display->xdisplay, screen->xroot,
                   screen->display->atom_net_current_desktop,
                   XA_CARDINAL,
                   32, PropModeReplace, (guchar*) data, 1);
  return meta_error_trap_pop (screen->display);
}