/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */

/* MetaGroup property handling */

/*
 * Copyright (C) 2002 Red Hat, Inc.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include <config.h>
#include "group-props.h"
#include "group-private.h"
#include "xprops.h"
#include "x11/meta-x11-display-private.h"
#include <X11/Xatom.h>

typedef void (* InitValueFunc)   (MetaX11Display *x11_display,
                                  Atom            property,
                                  MetaPropValue  *value);
typedef void (* ReloadValueFunc) (MetaGroup      *group,
                                  MetaPropValue  *value);

struct _MetaGroupPropHooks
{
  Atom property;
  InitValueFunc   init_func;
  ReloadValueFunc reload_func;
};

static void                init_prop_value   (MetaX11Display *x11_display,
                                              Atom            property,
                                              MetaPropValue  *value);
static void                reload_prop_value (MetaGroup      *group,
                                              MetaPropValue  *value);
static MetaGroupPropHooks *find_hooks        (MetaX11Display *x11_display,
                                              Atom            property);

void
meta_group_reload_property (MetaGroup *group,
                            Atom       property)
{
  meta_group_reload_properties (group, &property, 1);
}

void
meta_group_reload_properties (MetaGroup  *group,
                              const Atom *properties,
                              int         n_properties)
{
  int i;
  MetaPropValue *values;

  g_return_if_fail (properties != NULL);
  g_return_if_fail (n_properties > 0);

  values = g_new0 (MetaPropValue, n_properties);

  i = 0;
  while (i < n_properties)
    {
      init_prop_value (group->x11_display, properties[i], &values[i]);
      ++i;
    }

  meta_prop_get_values (group->x11_display,
                        group->group_leader,
                        values, n_properties);

  i = 0;
  while (i < n_properties)
    {
      reload_prop_value (group, &values[i]);

      ++i;
    }

  meta_prop_free_values (values, n_properties);

  g_free (values);
}

/* Fill in the MetaPropValue used to get the value of "property" */
static void
init_prop_value (MetaX11Display *x11_display,
                 Atom            property,
                 MetaPropValue  *value)
{
  MetaGroupPropHooks *hooks;

  value->type = META_PROP_VALUE_INVALID;
  value->atom = None;

  hooks = find_hooks (x11_display, property);
  if (hooks && hooks->init_func != NULL)
    (* hooks->init_func) (x11_display, property, value);
}

static void
reload_prop_value (MetaGroup    *group,
                   MetaPropValue *value)
{
  MetaGroupPropHooks *hooks;

  hooks = find_hooks (group->x11_display, value->atom);
  if (hooks && hooks->reload_func != NULL)
    (* hooks->reload_func) (group, value);
}

static void
init_wm_client_machine (MetaX11Display *x11_display,
                        Atom            property,
                        MetaPropValue  *value)
{
  value->type = META_PROP_VALUE_STRING;
  value->atom = x11_display->atom_WM_CLIENT_MACHINE;
}

static void
reload_wm_client_machine (MetaGroup     *group,
                          MetaPropValue *value)
{
  g_free (group->wm_client_machine);
  group->wm_client_machine = NULL;

  if (value->type != META_PROP_VALUE_INVALID)
    group->wm_client_machine = g_strdup (value->v.str);

  meta_verbose ("Group has client machine \"%s\"\n",
                group->wm_client_machine ? group->wm_client_machine : "unset");
}

static void
init_net_startup_id (MetaX11Display *x11_display,
                     Atom            property,
                     MetaPropValue  *value)
{
  value->type = META_PROP_VALUE_UTF8;
  value->atom = x11_display->atom__NET_STARTUP_ID;
}

static void
reload_net_startup_id (MetaGroup     *group,
                       MetaPropValue *value)
{
  g_free (group->startup_id);
  group->startup_id = NULL;

  if (value->type != META_PROP_VALUE_INVALID)
    group->startup_id = g_strdup (value->v.str);

  meta_verbose ("Group has startup id \"%s\"\n",
                group->startup_id ? group->startup_id : "unset");
}

#define N_HOOKS 3

void
meta_x11_display_init_group_prop_hooks (MetaX11Display *x11_display)
{
  int i;
  MetaGroupPropHooks *hooks;

  g_assert (x11_display->group_prop_hooks == NULL);

  x11_display->group_prop_hooks = g_new0 (MetaGroupPropHooks, N_HOOKS);
  hooks = x11_display->group_prop_hooks;

  i = 0;

  hooks[i].property = x11_display->atom_WM_CLIENT_MACHINE;
  hooks[i].init_func = init_wm_client_machine;
  hooks[i].reload_func = reload_wm_client_machine;
  ++i;

  hooks[i].property = x11_display->atom__NET_WM_PID;
  hooks[i].init_func = NULL;
  hooks[i].reload_func = NULL;
  ++i;

  hooks[i].property = x11_display->atom__NET_STARTUP_ID;
  hooks[i].init_func = init_net_startup_id;
  hooks[i].reload_func = reload_net_startup_id;
  ++i;

  if (i != N_HOOKS)
    {
      g_error ("Initialized %d group hooks should have been %d\n", i, N_HOOKS);
    }
}

void
meta_x11_display_free_group_prop_hooks (MetaX11Display *x11_display)
{
  g_assert (x11_display->group_prop_hooks != NULL);

  g_free (x11_display->group_prop_hooks);
  x11_display->group_prop_hooks = NULL;
}

static MetaGroupPropHooks*
find_hooks (MetaX11Display *x11_display,
            Atom            property)
{
  int i;

  /* FIXME we could sort the array and do binary search or
   * something
   */

  i = 0;
  while (i < N_HOOKS)
    {
      if (x11_display->group_prop_hooks[i].property == property)
        return &x11_display->group_prop_hooks[i];

      ++i;
    }

  return NULL;
}
