mutter/src/workspace.c

/* Metacity Workspaces */

/* 
 * Copyright (C) 2001 Havoc Pennington
 * Copyright (C) 2003 Rob Adams
 * Copyright (C) 2004, 2005 Elijah Newren
 * 
 * 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 <config.h>
#include "workspace.h"
#include "errors.h"
#include "prefs.h"
#include <X11/Xatom.h>
#include <string.h>

void meta_workspace_queue_calc_showing   (MetaWorkspace *workspace);
static void set_active_space_hint        (MetaScreen *screen);
static void focus_ancestor_or_mru_window (MetaWorkspace *workspace,
                                          MetaWindow    *not_this_one,
                                          Time           timestamp);

static void
maybe_add_to_list (MetaScreen *screen, MetaWindow *window, gpointer data)
{
  GList **mru_list = data;

  if (window->on_all_workspaces)
    *mru_list = g_list_prepend (*mru_list, window);
}

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

  workspace = g_new (MetaWorkspace, 1);

  workspace->screen = screen;
  workspace->screen->workspaces =
    g_list_append (workspace->screen->workspaces, workspace);
  workspace->windows = NULL;
  workspace->mru_list = NULL;
  meta_screen_foreach_window (screen, maybe_add_to_list, &workspace->mru_list);

  workspace->work_areas = NULL;
  workspace->work_areas_invalid = TRUE;
  workspace->all_work_areas.x = 0;
  workspace->all_work_areas.y = 0;
  workspace->all_work_areas.width = 0;
  workspace->all_work_areas.height = 0;

  workspace->left_struts = NULL;
  workspace->right_struts = NULL;
  workspace->top_struts = NULL;
  workspace->bottom_struts = NULL;

  workspace->showing_desktop = FALSE;
  
  return workspace;
}

void
meta_workspace_free (MetaWorkspace *workspace)
{
  GList *tmp;
  MetaScreen *screen;

  g_return_if_fail (workspace != workspace->screen->active_workspace);

  /* Here we assume all the windows are already on another workspace
   * as well, so they won't be "orphaned"
   */
  
  tmp = workspace->windows;
  while (tmp != NULL)
    {
      GList *next;
      MetaWindow *window = tmp->data;
      next = tmp->next;

      /* pop front of list we're iterating over */
      meta_workspace_remove_window (workspace, window);
      g_assert (window->workspace != NULL);

      tmp = next;
    }

  g_assert (workspace->windows == NULL);

  screen = workspace->screen;
  
  workspace->screen->workspaces =
    g_list_remove (workspace->screen->workspaces, workspace);
  
  g_free (workspace->work_areas);

  g_list_free (workspace->mru_list);
  g_slist_free (workspace->left_struts);
  g_slist_free (workspace->right_struts);
  g_slist_free (workspace->top_struts);
  g_slist_free (workspace->bottom_struts);

  g_free (workspace);

  /* don't bother to reset names, pagers can just ignore
   * extra ones
   */
}

void
meta_workspace_add_window (MetaWorkspace *workspace,
                           MetaWindow    *window)
{
  g_return_if_fail (window->workspace == NULL);
  
  /* If the window is on all workspaces, we want to add it to all mru
   * lists, otherwise just add it to this workspaces mru list
   */
  if (window->on_all_workspaces) 
    {
      if (window->workspace == NULL)
        {
          GList* tmp = window->screen->workspaces;
          while (tmp)
            {
              MetaWorkspace* work = (MetaWorkspace*) tmp->data;
              if (!g_list_find (work->mru_list, window))
                work->mru_list = g_list_prepend (work->mru_list, window);

              tmp = tmp->next;
            }
        }
    }
  else
    {
      g_assert (g_list_find (workspace->mru_list, window) == NULL);
      workspace->mru_list = g_list_prepend (workspace->mru_list, window);
    }

  workspace->windows = g_list_prepend (workspace->windows, window);
  window->workspace = workspace;

  meta_window_set_current_workspace_hint (window);
  
  meta_window_queue_calc_showing (window);
  if (window->struts)
    {
      meta_topic (META_DEBUG_WORKAREA,
                  "Invalidating work area of workspace %d since we're adding window %s to it\n",
                  meta_workspace_index (workspace), window->desc);
      meta_workspace_invalidate_work_area (workspace);
    }

  /* queue a move_resize since changing workspaces may change
   * the relevant struts
   */
  meta_window_queue_move_resize (window);
}

void
meta_workspace_remove_window (MetaWorkspace *workspace,
                              MetaWindow    *window)
{
  g_return_if_fail (window->workspace == workspace);

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

  /* If the window is on all workspaces, we don't want to remove it
   * from the MRU list unless this causes it to be removed from all 
   * workspaces
   */
  if (window->on_all_workspaces) 
    {
      GList* tmp = window->screen->workspaces;
      while (tmp)
        {
          MetaWorkspace* work = (MetaWorkspace*) tmp->data;
          work->mru_list = g_list_remove (work->mru_list, window);

          tmp = tmp->next;
        }
    }
  else
    {
      workspace->mru_list = g_list_remove (workspace->mru_list, window);
      g_assert (g_list_find (workspace->mru_list, window) == NULL);
    }

  meta_window_set_current_workspace_hint (window);
  
  meta_window_queue_calc_showing (window);

  if (window->struts)
    {
      meta_topic (META_DEBUG_WORKAREA,
                  "Invalidating work area of workspace %d since we're removing window %s from it\n",
                  meta_workspace_index (workspace), window->desc);
      meta_workspace_invalidate_work_area (workspace);
    }

  /* queue a move_resize since changing workspaces may change
   * the relevant struts
   */
  meta_window_queue_move_resize (window);
}

void
meta_workspace_relocate_windows (MetaWorkspace *workspace,
                                 MetaWorkspace *new_home)
{
  GList *tmp;
  GList *copy;
  
  g_return_if_fail (workspace != new_home);

  /* can't modify list we're iterating over */
  copy = g_list_copy (workspace->windows);
  
  tmp = copy;
  while (tmp != NULL)
    {
      MetaWindow *window = tmp->data;

      meta_workspace_add_window (new_home, window);
      meta_workspace_remove_window (workspace, window);
      
      tmp = tmp->next;
    }

  g_list_free (copy);
  
  g_assert (workspace->windows == 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_with_focus (MetaWorkspace *workspace,
                                    MetaWindow    *focus_this,
                                    Time           timestamp)
{
  MetaWorkspace *old;
  MetaWindow *move_window;
  
  meta_verbose ("Activating workspace %d\n",
                meta_workspace_index (workspace));
  
  if (workspace->screen->active_workspace == workspace)
    return;

  /* Note that old can be NULL; e.g. when starting up */
  old = workspace->screen->active_workspace;
  
  workspace->screen->active_workspace = workspace;

  set_active_space_hint (workspace->screen);

  /* If the "show desktop" mode is active for either the old workspace
   * or the new one *but not both*, then update the
   * _net_showing_desktop hint
   */
  if (old && (old->showing_desktop ^ workspace->showing_desktop))
    meta_screen_update_showing_desktop_hint (workspace->screen);

  if (old == NULL)
    return;

  move_window = NULL;
  if (workspace->screen->display->grab_op == META_GRAB_OP_MOVING ||
      workspace->screen->display->grab_op == META_GRAB_OP_KEYBOARD_MOVING)
    move_window = workspace->screen->display->grab_window;
      
  if (move_window != NULL)
    {
      if (move_window->on_all_workspaces)
        move_window = NULL; /* don't move it after all */

      /* We put the window on the new workspace, flip spaces,
       * then remove from old workspace, so the window
       * never gets unmapped and we maintain the button grab
       * on it.
       */
      if (move_window && (move_window->workspace != workspace))
        {
          meta_workspace_remove_window (workspace, move_window);
          meta_workspace_add_window (workspace, move_window);
        }
    }

  meta_workspace_queue_calc_showing (old);
  meta_workspace_queue_calc_showing (workspace);

  /* FIXME: Why do we need this?!?  Isn't it handled in the lines above? */
  if (move_window)
      /* Removes window from other spaces */
      meta_window_change_workspace (move_window, workspace);

  if (focus_this)
    {
      meta_window_focus (focus_this, timestamp);
      meta_window_raise (focus_this);
    }
  else if (move_window)
    {
      meta_window_raise (move_window);
    }
  else
    {
      meta_topic (META_DEBUG_FOCUS, "Focusing default window on new workspace\n");
      meta_workspace_focus_default_window (workspace, NULL, timestamp);
    }
}

void
meta_workspace_activate (MetaWorkspace *workspace,
                         Time           timestamp)
{
  meta_workspace_activate_with_focus (workspace, NULL, timestamp);
}

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

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

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

  meta_bug ("Workspace does not exist to index!\n");
  return -1; /* compiler warnings */
}

/* get windows contained on workspace, including workspace->windows
 * and also sticky windows.
 */
GList*
meta_workspace_list_windows (MetaWorkspace *workspace)
{
  GSList *display_windows;
  GSList *tmp;
  GList *workspace_windows;
  
  display_windows = meta_display_list_windows (workspace->screen->display);

  workspace_windows = NULL;
  tmp = display_windows;
  while (tmp != NULL)
    {
      MetaWindow *window = tmp->data;

      if (meta_window_located_on_workspace (window, workspace))
        workspace_windows = g_list_prepend (workspace_windows,
                                            window);

      tmp = tmp->next;
    }

  g_slist_free (display_windows);

  return workspace_windows;
}

static void
set_active_space_hint (MetaScreen *screen)
{
  unsigned long data[1];

  /* this is because we destroy the spaces in order,
   * so we always end up setting a current desktop of
   * 0 when closing a screen, so lose the current desktop
   * on restart. By doing this we keep the current
   * desktop on restart.
   */
  if (screen->closing > 0)
    return;
  
  data[0] = meta_workspace_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);
  meta_error_trap_pop (screen->display, FALSE);
}

void
meta_workspace_invalidate_work_area (MetaWorkspace *workspace)
{
  GList *tmp;
  GList *windows;
  
  if (workspace->work_areas_invalid)
    {
      meta_topic (META_DEBUG_WORKAREA,
                  "Work area for workspace %d is already invalid\n",
                  meta_workspace_index (workspace));
      return;
    }

  meta_topic (META_DEBUG_WORKAREA,
              "Invalidating work area for workspace %d\n",
              meta_workspace_index (workspace));

  g_free (workspace->work_areas);
  workspace->work_areas = NULL;
      
  g_slist_free (workspace->left_struts);
  workspace->left_struts = NULL;
  g_slist_free (workspace->right_struts);
  workspace->right_struts = NULL;
  g_slist_free (workspace->top_struts);
  workspace->top_struts = NULL;
  g_slist_free (workspace->bottom_struts);
  workspace->bottom_struts = NULL;
  
  workspace->work_areas_invalid = TRUE;

  /* redo the size/position constraints on all windows */
  windows = meta_workspace_list_windows (workspace);
  tmp = windows;
  while (tmp != NULL)
    {
      MetaWindow *w = tmp->data;

      meta_window_queue_move_resize (w);
      
      tmp = tmp->next;
    }

  g_list_free (windows);

  meta_screen_queue_workarea_recalc (workspace->screen);
}

static void
ensure_work_areas_validated (MetaWorkspace *workspace)
{
  int left_strut = 0;
  int right_strut = 0;
  int top_strut = 0;
  int bottom_strut = 0;
  int all_left_strut = 0;
  int all_right_strut = 0;
  int all_top_strut = 0;
  int all_bottom_strut = 0;
  int i;
  GList *tmp;
  GList *windows;

  if (!workspace->work_areas_invalid)
    return;

  g_assert (workspace->top_struts == NULL);
  g_assert (workspace->bottom_struts == NULL);
  g_assert (workspace->left_struts == NULL);
  g_assert (workspace->right_struts == NULL);
  
  windows = meta_workspace_list_windows (workspace);

  g_free (workspace->work_areas);
  workspace->work_areas = g_new (MetaRectangle,
                                 workspace->screen->n_xinerama_infos);
      
  i = 0;
  while (i < workspace->screen->n_xinerama_infos)
    {
      left_strut = 0;
      right_strut = 0;
      top_strut = 0;
      bottom_strut = 0;

      tmp = windows;
      while (tmp != NULL)
        {
          MetaWindow *w = tmp->data;

          if (w->struts)
            {
              meta_topic (META_DEBUG_WORKAREA,
                          "Merging win %s with %d %d %d %d "
                          "with %d %d %d %d\n",
                          w->desc,
                          w->struts->left.width, w->struts->right.width, 
                          w->struts->top.height, w->struts->bottom.height,
                          left_strut, right_strut, 
                          top_strut, bottom_strut);

              if ((i == 0) && (w->struts->left.width > 0))
                {
                  workspace->left_struts = g_slist_prepend (workspace->left_struts,
                                                            &w->struts->left);
                }

              if (meta_screen_rect_intersects_xinerama (w->screen,
                                                        &w->struts->left,
                                                        i))
                {
                  left_strut = MAX (left_strut, 
                                    w->struts->left.width - 
                                    workspace->screen->xinerama_infos[i].x_origin);
                  all_left_strut = MAX (all_left_strut, w->struts->left.width);
                }

              if ((i == 0) && (w->struts->right.width > 0))
                {
                  workspace->right_struts = g_slist_prepend (workspace->right_struts,
                                                             &w->struts->right);
                }

              if (meta_screen_rect_intersects_xinerama (w->screen,
                                                        &w->struts->right,
                                                        i))
                {
                  right_strut = MAX (right_strut, w->struts->right.width - 
                                     workspace->screen->width + 
                                     workspace->screen->xinerama_infos[i].width +
                                     workspace->screen->xinerama_infos[i].x_origin);
                  all_right_strut = MAX (all_right_strut, w->struts->right.width);
                }

              if ((i == 0) && (w->struts->top.height > 0))
                {
                  workspace->top_struts = g_slist_prepend (workspace->top_struts,
                                                           &w->struts->top);
                }

              if (meta_screen_rect_intersects_xinerama (w->screen,
                                                        &w->struts->top,
                                                        i))
                {
                  top_strut = MAX (top_strut,
                                   w->struts->top.height - 
                                   workspace->screen->xinerama_infos[i].y_origin);
                  all_top_strut = MAX (all_top_strut, w->struts->top.height);
                }

              if ((i == 0) && (w->struts->bottom.height > 0))
                {
                  workspace->bottom_struts = g_slist_prepend (workspace->bottom_struts,
                                                              &w->struts->bottom);
                }

              if (meta_screen_rect_intersects_xinerama (w->screen,
                                                        &w->struts->bottom,
                                                        i))
                {
                  bottom_strut = MAX (bottom_strut, w->struts->bottom.height - 
                                     workspace->screen->height + 
                                     workspace->screen->xinerama_infos[i].height +
                                     workspace->screen->xinerama_infos[i].y_origin);
                  all_bottom_strut = MAX (all_bottom_strut, w->struts->bottom.height);
                }
            }
          
          tmp = tmp->next;
        }

      /* Some paranoid robustness */
#define MIN_SANE_AREA 100
      
      if ((left_strut + right_strut) > 
          (workspace->screen->xinerama_infos[i].width - MIN_SANE_AREA))
        {
          meta_topic (META_DEBUG_WORKAREA,
                      "Making left/right struts %d %d sane xinerama %d\n",
                      left_strut, right_strut, i);
          left_strut = (workspace->screen->xinerama_infos[i].width - 
                        MIN_SANE_AREA) / 2;
          right_strut = left_strut;
        }

      if ((top_strut + bottom_strut) > 
          (workspace->screen->xinerama_infos[i].height - MIN_SANE_AREA))
        {
          meta_topic (META_DEBUG_WORKAREA,
                      "Making top/bottom struts %d %d sane xinerama %d\n",
                      top_strut, bottom_strut, i);
          top_strut = (workspace->screen->xinerama_infos[i].height - 
                       MIN_SANE_AREA) / 2;
          bottom_strut = top_strut;
        }

      workspace->work_areas[i].x = 
        left_strut + workspace->screen->xinerama_infos[i].x_origin;
      workspace->work_areas[i].y = top_strut + 
        workspace->screen->xinerama_infos[i].y_origin;
      workspace->work_areas[i].width = 
        workspace->screen->xinerama_infos[i].width - 
        left_strut - right_strut;
      workspace->work_areas[i].height = 
        workspace->screen->xinerama_infos[i].height - 
        top_strut - bottom_strut;

      meta_topic (META_DEBUG_WORKAREA,
                  "Computed work area for workspace %d "
                  "xinerama %d: %d,%d %d x %d\n",
                  meta_workspace_index (workspace),
                  i,
                  workspace->work_areas[i].x,
                  workspace->work_areas[i].y,
                  workspace->work_areas[i].width,
                  workspace->work_areas[i].height);

      ++i;
    }

  g_list_free (windows);

  if ((all_left_strut + all_right_strut) > 
      (workspace->screen->width - MIN_SANE_AREA))
    {
      meta_topic (META_DEBUG_WORKAREA,
                  "Making screen-wide left/right struts %d %d sane\n",
                  all_left_strut, all_right_strut);
      all_left_strut = (workspace->screen->width - MIN_SANE_AREA) / 2;
      all_right_strut = all_left_strut;
    }
      
  if ((all_top_strut + all_bottom_strut) > 
      (workspace->screen->height - MIN_SANE_AREA))
    {
      meta_topic (META_DEBUG_WORKAREA,
                  "Making top/bottom struts %d %d sane\n",
                  all_top_strut, all_bottom_strut);
      all_top_strut = (workspace->screen->height - MIN_SANE_AREA) / 2;
      all_bottom_strut = all_top_strut;
    }
      
  workspace->all_work_areas.x = all_left_strut;
  workspace->all_work_areas.y = all_top_strut;
  workspace->all_work_areas.width = 
    workspace->screen->width - all_left_strut - all_right_strut;
  workspace->all_work_areas.height = 
    workspace->screen->height - all_top_strut - all_bottom_strut;
  
  workspace->work_areas_invalid = FALSE;

  meta_topic (META_DEBUG_WORKAREA,
              "Computed work area for workspace %d: %d,%d %d x %d\n",
              meta_workspace_index (workspace),
              workspace->all_work_areas.x,
              workspace->all_work_areas.y,
              workspace->all_work_areas.width,
              workspace->all_work_areas.height);    
}

void
meta_workspace_get_work_area_for_xinerama (MetaWorkspace *workspace,
                                           int            which_xinerama,
                                           MetaRectangle *area)
{
  g_assert (which_xinerama >= 0);

  ensure_work_areas_validated (workspace);
  g_assert (which_xinerama < workspace->screen->n_xinerama_infos);
  
  *area = workspace->work_areas[which_xinerama];
}

void
meta_workspace_get_work_area_all_xineramas (MetaWorkspace *workspace,
                                            MetaRectangle *area)
{
  ensure_work_areas_validated (workspace);
  
  *area = workspace->all_work_areas;
}

#ifdef WITH_VERBOSE_MODE
static char *
meta_motion_direction_to_string (MetaMotionDirection direction)
{
  switch (direction)
    {
    case META_MOTION_UP:
      return "Up";
    case META_MOTION_DOWN:
      return "Down";
    case META_MOTION_LEFT:
      return "Left";
    case META_MOTION_RIGHT:
      return "Right";
    }

  return "Unknown";
}
#endif /* WITH_VERBOSE_MODE */

MetaWorkspace*
meta_workspace_get_neighbor (MetaWorkspace      *workspace,
                             MetaMotionDirection direction)
{
  MetaWorkspaceLayout layout;  
  int i, current_space, num_workspaces;

  current_space = meta_workspace_index (workspace);
  num_workspaces = meta_screen_get_n_workspaces (workspace->screen);
  meta_screen_calc_workspace_layout (workspace->screen, num_workspaces,
                                     current_space, &layout);

  meta_verbose ("Getting neighbor of %d in direction %s\n",
                current_space, meta_motion_direction_to_string (direction));
  
  switch (direction) 
    {
    case META_MOTION_LEFT:
      layout.current_col -= 1;
      break;
    case META_MOTION_RIGHT:
      layout.current_col += 1;
      break;
    case META_MOTION_UP:
      layout.current_row -= 1;
      break;
    case META_MOTION_DOWN:
      layout.current_row += 1;
      break;
    }

  if (layout.current_col < 0)
    layout.current_col = 0;
  if (layout.current_col >= layout.cols)
    layout.current_col = layout.cols - 1;
  if (layout.current_row < 0)
    layout.current_row = 0;
  if (layout.current_row >= layout.rows)
    layout.current_row = layout.rows - 1;

  i = layout.grid[layout.current_row * layout.cols + layout.current_col];

  if (i < 0)
    i = current_space;

  if (i >= num_workspaces)
    meta_bug ("calc_workspace_layout left an invalid (too-high) workspace number %d in the grid\n",
              i);
    
  meta_verbose ("Neighbor workspace is %d at row %d col %d\n",
                i, layout.current_row, layout.current_col);

  meta_screen_free_workspace_layout (&layout);
  
  return meta_screen_get_workspace_by_index (workspace->screen, i);
}

const char*
meta_workspace_get_name (MetaWorkspace *workspace)
{
  return meta_prefs_get_workspace_name (meta_workspace_index (workspace));
}

void
meta_workspace_focus_default_window (MetaWorkspace *workspace,
                                     MetaWindow    *not_this_one,
                                     Time           timestamp)
{
  if (timestamp == CurrentTime)
    {
      meta_warning ("CurrentTime used to choose focus window; "
                    "focus window may not be correct.\n");
    }


  if (meta_prefs_get_focus_mode () == META_FOCUS_MODE_CLICK ||
      !workspace->screen->display->mouse_mode)
    focus_ancestor_or_mru_window (workspace, not_this_one, timestamp);
  else
    {
      MetaWindow * window;
      window = meta_screen_get_mouse_window (workspace->screen, not_this_one);
      if (window &&
          window->type != META_WINDOW_DOCK &&
          window->type != META_WINDOW_DESKTOP)
        {
          if (timestamp == CurrentTime)
            {

              /* We would like for this to never happen.  However, if
               * it does happen then we kludge since using CurrentTime
               * can mean ugly race conditions--and we can avoid these
               * by allowing EnterNotify events (which come with
               * timestamps) to handle focus.
               */

              meta_topic (META_DEBUG_FOCUS,
                          "Not focusing mouse window %s because EnterNotify events should handle that\n", window->desc);
            }
          else
            {
              meta_topic (META_DEBUG_FOCUS,
                          "Focusing mouse window %s\n", window->desc);
              meta_window_focus (window, timestamp);
            }

          if (workspace->screen->display->autoraise_window != window &&
              meta_prefs_get_auto_raise ()) 
            {
              meta_display_queue_autoraise_callback (workspace->screen->display,
                                                     window);
            }
        }
      else if (meta_prefs_get_focus_mode () == META_FOCUS_MODE_SLOPPY)
        focus_ancestor_or_mru_window (workspace, not_this_one, timestamp);
      else if (meta_prefs_get_focus_mode () == META_FOCUS_MODE_MOUSE)
        {
          meta_topic (META_DEBUG_FOCUS,
                      "Setting focus to no_focus_window, since no valid "
                      "window to focus found.\n");
          meta_display_focus_the_no_focus_window (workspace->screen->display,
                                                  timestamp);
        }
    }
}

static gboolean
record_ancestor (MetaWindow *window,
                 void       *data)
{
  MetaWindow **result = data;

  *result = window;
  return FALSE; /* quit with the first ancestor we find */
}

/* Focus ancestor of not_this_one if there is one, otherwise focus the MRU
 * window on active workspace
 */
static void
focus_ancestor_or_mru_window (MetaWorkspace *workspace,
                              MetaWindow    *not_this_one,
                              Time           timestamp)
{
  MetaWindow *window = NULL;
  GList *tmp;

  if (not_this_one)
    meta_topic (META_DEBUG_FOCUS,
                "Focusing MRU window excluding %s\n", not_this_one->desc);
  else
    meta_topic (META_DEBUG_FOCUS,
                "Focusing MRU window\n");

  /* First, check to see if we need to focus an ancestor of a window */  
  if (not_this_one)
    {
      MetaWindow *ancestor;
      ancestor = NULL;
      meta_window_foreach_ancestor (not_this_one, record_ancestor, &ancestor);
      if (ancestor != NULL)
        {
          meta_topic (META_DEBUG_FOCUS,
                      "Focusing %s, ancestor of %s\n", 
                      ancestor->desc, not_this_one->desc);
      
          meta_window_focus (ancestor, timestamp);

          /* Also raise the window if in click-to-focus */
          if (meta_prefs_get_focus_mode () == META_FOCUS_MODE_CLICK)
            meta_window_raise (ancestor);

          return;
        }
    }

  /* No ancestor, look for the MRU window */
  tmp = workspace->mru_list;  

  while (tmp)
    {
      MetaWindow* tmp_window;
      tmp_window = ((MetaWindow*) tmp->data);
      if (tmp_window != not_this_one           &&
          meta_window_showing_on_its_workspace (tmp_window) &&
          tmp_window->type != META_WINDOW_DOCK &&
          tmp_window->type != META_WINDOW_DESKTOP)
        {
          window = tmp->data;
	  break;
        }

      tmp = tmp->next;
    }

  if (window)
    {
      meta_topic (META_DEBUG_FOCUS,
                  "Focusing workspace MRU window %s\n", window->desc);
      
      meta_window_focus (window, timestamp);

      /* Also raise the window if in click-to-focus */
      if (meta_prefs_get_focus_mode () == META_FOCUS_MODE_CLICK)
        meta_window_raise (window);
    }
  else
    {
      meta_topic (META_DEBUG_FOCUS, "No MRU window to focus found; focusing no_focus_window.\n");
      meta_display_focus_the_no_focus_window (workspace->screen->display,
                                              timestamp);
    }
}