/*==================================================================
 * SwamiUndoFuncs.c - Swami item type undo functions
 *
 * Swami
 * Copyright (C) 1999-2003 Josh Green <jgreen@users.sourceforge.net>
 *
 * 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 or point your web browser to http://www.gnu.org.
 *
 * To contact the author of this program:
 * Email: Josh Green <jgreen@users.sourceforge.net>
 * Swami homepage: http://swami.sourceforge.net
 *==================================================================*/

#include <stdio.h>
#include <instpatch.h>

#include "SwamiUndoFuncs.h"
#include "SwamiObject.h"
#include "i18n.h"

static void item_new_restore (SwamiObject *swami, const SwamiUndoItem *doitem);
static void item_new_restate (SwamiObject *swami, const SwamiUndoItem *doitem,
			      SwamiUndoItem *newitem);
static void item_new_free (SwamiObject *swami, SwamiUndoItem *doitem);
static gpointer item_new_save_state (IPItem *sfitem);

static void item_remove_restore (SwamiObject *swami,
				 const SwamiUndoItem *doitem);
static void item_remove_restate (SwamiObject *swami,
				 const SwamiUndoItem *doitem,
				 SwamiUndoItem *newitem);
static void item_remove_free (SwamiObject *swami, SwamiUndoItem *doitem);
static gpointer item_remove_save_state (IPItem *sfitem);

static void property_change_restore (SwamiObject *swami,
				     const SwamiUndoItem *doitem);
static void property_change_restate (SwamiObject *swami,
				     const SwamiUndoItem *doitem,
				     SwamiUndoItem *newitem);
static void property_change_free (SwamiObject *swami, SwamiUndoItem *doitem);
static gpointer property_change_save_state (SwamiObject *swami, IPItem *sfitem,
					    const char *property_name);

SwamiUndoTypeInfo swami_undo_type_info [] = {
  { NULL, NULL, NULL},      /* SWAMI_UNDO_NONE */
    { N_("New sound font item"), item_new_restore,
      item_new_restate, item_new_free },
    { N_("Remove sound font item"), item_remove_restore,
      item_remove_restate, item_remove_free },
  { N_("Sound font item property change"), property_change_restore,
    property_change_restate, property_change_free },
};


/* ------------------------------------------------ */
/* created item save state (state of non-existence) */
/* ------------------------------------------------ */

void
swami_undo_save_item_new (SwamiObject *swami, IPItem *sfitem)
{
  gpointer st;

  g_return_if_fail (swami != NULL);
  g_return_if_fail (sfitem != NULL);

  SWAMI_UNDO_ENTER (swami);

  st = item_new_save_state (sfitem);
  swami_undo_item_add (swami, SWAMI_UNDO_ITEM_NEW, st);
}

static void
item_new_restore (SwamiObject *swami, const SwamiUndoItem *doitem)
{
  /* unlink item (the original state) */
  instp_item_unlink (INSTP_ITEM (doitem->state));
}

/* save redo state (SF item itself) */
static void
item_new_restate (SwamiObject *swami, const SwamiUndoItem *doitem,
		  SwamiUndoItem *newitem)
{
  newitem->type = SWAMI_UNDO_ITEM_REMOVE;
  newitem->state = item_remove_save_state (INSTP_ITEM (doitem->state));
}

static void
item_new_free (SwamiObject *swami, SwamiUndoItem *doitem)
{
  instp_item_unref (INSTP_ITEM (doitem->state)); /* release undo reference */
}

static gpointer
item_new_save_state (IPItem *sfitem)
{
  /* add a reference to the item (undo now referencing it) */
  instp_item_ref (sfitem);
  return (sfitem);		/* return item pointer as state data */
}

/* ------------------------------------- */
/* item remove undo type (save the item) */
/* ------------------------------------- */

typedef struct _ItemRemoveState
{
  IPItem *sfitem;
  IPItem *parent;
  IPItem *next;
}
ItemRemoveState;

void
swami_undo_save_item_remove (SwamiObject *swami, IPItem *sfitem)
{
  gpointer st;

  g_return_if_fail (swami != NULL);
  g_return_if_fail (sfitem != NULL);

  SWAMI_UNDO_ENTER (swami);

  st = item_remove_save_state (sfitem);
  swami_undo_item_add (swami, SWAMI_UNDO_ITEM_REMOVE, st);
}

static void
item_remove_restore (SwamiObject *swami, const SwamiUndoItem *doitem)
{
  ItemRemoveState *st = doitem->state;

  /* insert item (restore original state) */
  instp_item_insert_before (st->parent, st->sfitem, st->next);
}

static void
item_remove_restate (SwamiObject *swami, const SwamiUndoItem *doitem,
		     SwamiUndoItem *newitem)
{
  ItemRemoveState *st = doitem->state;

  newitem->type = SWAMI_UNDO_ITEM_NEW;
  newitem->state = item_new_save_state (st->sfitem);
}

static void
item_remove_free (SwamiObject *swami, SwamiUndoItem *doitem)
{
  ItemRemoveState *st = doitem->state;

  instp_item_unref (st->sfitem);
  instp_item_unref (st->parent);
  if (st->next) instp_item_unref (st->next);
  g_free (st);
}

/* save sound font item (reference it and save link pointers) */
static gpointer
item_remove_save_state (IPItem *sfitem)
{
  ItemRemoveState *st;

  st = g_malloc (sizeof (ItemRemoveState));
  st->sfitem = sfitem;
  st->parent = sfitem->parent;
  st->next = sfitem->next;

  /* increment item references for undo state */
  instp_item_ref (sfitem);
  instp_item_ref (sfitem->parent);
  if (sfitem->next) instp_item_ref (sfitem->next);

  return (st);
}

/* ------------------------------------- */
/* item property change                  */
/* ------------------------------------- */

typedef struct _PropertyChangeState
{
  IPItem *sfitem;
  char *property_name;
  GValue *value;
}
PropertyChangeState;

void
swami_undo_save_property_change (SwamiObject *swami, IPItem *sfitem,
				 const char *property_name)
{
  PropertyChangeState *st;

  g_return_if_fail (swami != NULL);
  g_return_if_fail (sfitem != NULL);
  g_return_if_fail (property_name != NULL);

  SWAMI_UNDO_ENTER (swami);

  st = property_change_save_state (swami, sfitem, property_name);
  swami_undo_item_add (swami, SWAMI_UNDO_PROPERTY_CHANGE, st);
}

static void
property_change_restore (SwamiObject *swami, const SwamiUndoItem *doitem)
{
  PropertyChangeState *st;

  st = doitem->state;
  swami_item_set_property (swami, st->sfitem, st->property_name, st->value);
}

static void
property_change_restate (SwamiObject *swami, const SwamiUndoItem *doitem,
			 SwamiUndoItem *newitem)
{
  PropertyChangeState *st;

  st = doitem->state;
  newitem->type = doitem->type;  /* just copy the type */
  newitem->state = property_change_save_state (swami, st->sfitem,
					       st->property_name);
}

static void
property_change_free (SwamiObject *swami, SwamiUndoItem *doitem)
{
  PropertyChangeState *st;

  st = doitem->state;

  instp_item_unref (st->sfitem);	/* release undo reference on item */

  if (st->value)
    {
      g_value_unset (st->value);
      g_free (st->value);
    }

  g_free (st->property_name);
  g_free (st);
}

static gpointer
property_change_save_state (SwamiObject *swami, IPItem *sfitem,
			    const char *property_name)
{
  PropertyChangeState *st;
  GValue v;

  st = g_malloc (sizeof (PropertyChangeState));

  st->sfitem = sfitem;
  instp_item_ref (sfitem);	/* add undo reference on item */

  st->property_name = g_strdup (property_name);

  g_value_init (&v, G_TYPE_STRING);
  if (swami_item_get_property (swami, sfitem, property_name, &v))
    {
      st->value = g_malloc (sizeof (GValue));
      g_value_init (st->value, G_VALUE_TYPE (&v));
      g_value_copy (&v, st->value);
    }
  else st->value = NULL;

  return (st);
}