/* GNOME calendar factory
 *
 * Copyright (C) 2000 Helix Code, Inc.
 *
 * Author: Federico Mena-Quintero <federico@helixcode.com>
 *
 * 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 "cal.h"
#include "cal-backend.h"
#include "cal-factory.h"
#include "job.h"



/* Private part of the CalFactory structure */
typedef struct {
	/* Hash table from GnomeVFSURI structures to CalBackend objects */
	GHashTable *backends;
} CalFactoryPrivate;



static void cal_factory_class_init (CalFactoryClass *class);
static void cal_factory_init (CalFactory *factory);
static void cal_factory_destroy (GtkObject *object);

static POA_GNOME_Calendar_CalFactory__vepv cal_factory_vepv;

static GnomeObjectClass *parent_class;



/**
 * cal_factory_get_type:
 * @void:
 *
 * Registers the #CalFactory class if necessary, and returns the type ID
 * associated to it.
 *
 * Return value: The type ID of the #CalFactory class.
 **/
GtkType
cal_factory_get_type (void)
{
	static GtkType cal_factory_type = 0;

	if (!cal_factory_type) {
		static const GtkTypeInfo cal_factory_info = {
			"CalFactory",
			sizeof (CalFactory),
			sizeof (CalFactoryClass),
			(GtkClassInitFunc) cal_factory_class_init,
			(GtkObjectInitFunc) cal_factory_init,
			NULL, /* reserved_1 */
			NULL, /* reserved_2 */
			(GtkClassInitFunc) NULL
		};

		cal_factory_type = gtk_type_unique (gnome_object_get_type (), &cal_factory_info);
	}

	return cal_factory_type;
}

/* CORBA class initialization function for the calendar factory */
static void
init_cal_factory_corba_class (void)
{
	cal_factory_vepv.GNOME_Unknown_epv = gnome_object_get_epv ();
	cal_factory_vepv.GNOME_Calendar_CalFactory_epv = cal_factory_get_epv ();
}

/* Class initialization function for the calendar factory */
static void
cal_factory_class_init (CalFactoryClass *class)
{
	GtkObjectClass *parent_class;

	object_class = (GtkObjectClass *) class;

	parent_class = gtk_type_class (gnome_object_get_type ());

	object_class->destroy = cal_factory_destroy;

	init_cal_factory_corba_class ();
}

/* Object initialization function for the calendar factory */
static void
cal_factory_init (CalFactory *factory)
{
	CalFactoryPrivate *priv;

	priv = g_new0 (CalFactoryPrivate, 1);
	factory->priv = priv;

	priv->backends = g_hash_table_new (gnome_vfs_uri_hash, gnome_vfs_uri_hequal);
}

/* Frees a uri/backend pair from the backends hash table */
static void
free_backend (gpointer key, gpointer value, gpointer data)
{
	GnomeVFSURI *uri;
	CalBackend *backend;

	uri = key;
	backend = value;

	gnome_vfs_uri_unref (uri);
	gtk_object_unref (GTK_OBJECT (backend));
}

/* Destroy handler for the calendar */
static void
cal_factory_destroy (GtkObject *object)
{
	CalFactory *factory;
	CalFactoryPrivate *priv;

	g_return_if_fail (object != NULL);
	g_return_if_fail (IS_CAL_FACTORY (object));

	factory = CAL_FACTORY (object);
	priv = factory->priv;

	g_hash_table_foreach (priv->backends, free_backend, NULL);
	g_hash_table_destroy (priv->backends);
	priv->backends = NULL;

	g_free (priv);

	if (GTK_OBJECT_CLASS (parent_class)->destroy)
		(* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
}



/* CORBA servant implementation */

/* CalFactory::load method */
static void
CalFactory_load (PortableServer_Servant servant,
		 CORBA_char *uri,
		 GNOME_Calendar_Listener listener,
		 CORBA_Environment *ev)
{
	CalFactory *factory;
	CalFactoryPrivate *priv;

	factory = CAL_FACTORY (gnome_object_from_servant (servant));
	priv = factory->priv;

	cal_factory_load (factory, uri, listener);
}

/* CalFactory::create method */
static GNOME_Calendar_Cal
CalFactory_create (PortableServer_Servant servant,
		   CORBA_char *uri,
		   GNOME_Calendar_Listener listener,
		   CORBA_Environment *ev)
{
	CalFactory *factory;
	CalFactoryPrivate *priv;

	factory = CAL_FACTORY (gnome_object_from_servant (servant));
	priv = factory->priv;

	cal_factory_create (factory, uri, listener);
}

/**
 * cal_factory_get_epv:
 * @void: 
 * 
 * Creates an EPV for the CalFactory CORBA class.
 * 
 * Return value: A newly-allocated EPV.
 **/
POA_GNOME_Calendar_CalFactory__epv *
cal_factory_get_epv (void)
{
	POA_GNOME_Calendar_CalFactory__epv *epv;

	epv = g_new0 (POA_GNOME_Calendar_CalFactory__epv, 1);
	epv->load = CalFactory_load;
	epv->create = CalFactory_create;

	return epv;
}



/* Loading and creating calendars */

/* Job data */
typedef struct {
	CalFactory *factory;
	char *uri;
	GNOME_Calendar_Listener listener;
} LoadCreateJobData;

/* Looks up a calendar backend in a factory's hash table of uri->cal */
static CalBackend *
lookup_backend (CalFactory *factory, GnomeVFSURI *uri)
{
	CalFactoryPrivate *priv;
	CalBackend *backend;

	priv = factory->priv;

	backend = g_hash_table_lookup (priv->backends, uri);
	return cal;
}

/* Loads a calendar backend and puts it in the factory's backend hash table */
static CalBackend *
load_backend (CalFactory *factory, GnomeVFSURI *uri, GNOME_Calendar_Listener listener)
{
	CalFactoryPrivate *priv;
	CalBackend *backend;
	CalBackendLoadStatus status;
	CORBA_Environment ev;

	priv = factory->priv;

	backend = cal_backend_new ();
	if (!backend) {
		g_message ("load_backend(): could not create the backend");
		return NULL;
	}

	status = cal_backend_load (backend, uri);

	switch (status) {
	case CAL_BACKEND_LOAD_SUCCESS:
		gnome_vfs_uri_ref (uri);
		g_hash_table_insert (priv->backends, uri, backend);

		return backend;

	case CAL_BACKEND_LOAD_ERROR:
		gtk_object_unref (backend);
		return NULL;

	default:
		g_assert_not_reached ();
		return NULL;
	}
}

/* Adds a listener to a calendar backend by creating a calendar client interface
 * object.
 */
static void
add_calendar_client (CalFactory *factory, CalBackend *backend, GNOME_Calendar_Listener listener)
{
	Cal *cal;
	CORBA_Environment ev;

	cal = cal_new (backend, listener);
	if (!cal) {
		g_message ("add_calendar_client(): could not create the calendar client interface");

		CORBA_exception_init (&ev);
		GNOME_Calendar_Listener_cal_loaded (listener,
						    GNOME_Calendar_Listener_ERROR,
						    CORBA_OBJECT_NIL,
						    &ev);
		if (ev._major != CORBA_NO_EXCEPTION)
			g_message ("add_calendar_client(): could not notify the listener");

		CORBA_exception_free (&ev);
		return;
	}

	cal_backend_add_cal (backend, cal);

	CORBA_exception_init (&ev);
	GNOME_Calendar_Listener_cal_loaded (listener,
					    GNOME_Calendar_Listener_SUCESSS,
					    gnome_object_corba_objref (GNOME_OBJECT (cal)),
					    &ev);

	if (ev._major != CORBA_NO_EXCEPTION) {
		g_message ("add_calendar_client(): could not notify the listener");
		cal_backend_remove_cal (backend, cal);
	}

	gtk_object_unref (GTK_OBJECT (cal));
}

/* Job handler for the load calendar command */
static void
load_fn (gpointer data)
{
	LoadCreateJobData jd;
	CalFactory *factory;
	GnomeVFSURI *uri;
	GNOME_Calendar_Listener listener;
	CalBackend *backend;
	CORBA_Environment ev;

	jd = data;

	/* Look up the calendar */

	uri = gnome_vfs_uri_new (jd->uri);
	g_free (jd->uri);

	factory = jd->factory;
	listener = jd->listener;
	g_free (jd);

	backend = lookup_backend (factory, uri);

	if (!backend)
		backend = load_backend (factory, uri, listener);

	gnome_vfs_uri_unref (uri);

	if (!backend) {
		g_message ("load_fn(): could not load the backend");
		CORBA_exception_init (&ev);
		GNOME_Calendar_Listener_cal_loaded (listener,
						    GNOME_Calendar_Listener_ERROR,
						    CORBA_OBJECT_NIL,
						    &ev);

		if (ev._major != CORBA_NO_EXCEPTION)
			g_message ("load_fn(): could not notify the listener");

		CORBA_exception_free (&ev);
		goto out;
	}

	add_calendar_client (factory, backend, listener);

 out:

	CORBA_exception_init (&ev);
	CORBA_Object_release (listener, &ev);

	if (ev._major != CORBA_NO_EXCEPTION)
		g_message ("load_fn(): could not release the listener");

	CORBA_exception_free (&ev);
}



/**
 * cal_factory_construct:
 * @factory: A calendar factory.
 * @corba_factory: CORBA object for the calendar factory.
 *
 * Constructs a calendar factory by binding the corresponding CORBA object to
 * it.
 *
 * Return value: The same object as the @factory argument.
 **/
CalFactory *
cal_factory_construct (CalFactory *factory, GNOME_Calendar_CalFactory corba_factory)
{
	g_return_val_if_fail (factory != NULL, NULL);
	g_return_val_if_fail (IS_CAL_FACTORY (factory), NULL);

	gnome_object_construct (GNOME_OBJECT (factory), corba_factory);
	return factory;
}

/**
 * cal_factory_corba_object_create:
 * @object: #GnomeObject that will wrap the CORBA object.
 *
 * Creates and activates the CORBA object that is wrapped by the specified
 * calendar factory @object.
 *
 * Return value: An activated object reference or #CORBA_OBJECT_NIL in case of
 * failure.
 **/
GNOME_Calendar_CalFactory
cal_factory_corba_object_create (GnomeObject *object)
{
	POA_GNOME_Calendar_CalFactory *servant;
	CORBA_Environment ev;

	g_return_val_if_fail (object != NULL, CORBA_OBJECT_NIL);
	g_return_val_if_fail (IS_CAL_FACTORY (object), CORBA_OBJECT_NIL);

	servant = (POA_GNOME_Calendar_CalFactory *) g_new0 (GnomeObjectServant, 1);
	servant->vepv = &cal_factory_vepv;

	CORBA_exception_init (&ev);
	POA_GNOME_Calendar_CalFactory__init ((PortableServer_Servant) servant, &ev);

	if (ev._major != CORBA_NO_EXCEPTION) {
		g_message ("cal_factory_corba_object_create(): could not init the servant");
		g_free (servant);
		CORBA_exception_free (&ev);
		return CORBA_OBJECT_NIL;
	}

	CORBA_exception_free (&ev);
	return (GNOME_Calendar_CalFactory) gnome_object_activate_servant (object, servant);
}

/**
 * cal_factory_new:
 * @void: 
 * 
 * Creates a new #CalFactory object.
 * 
 * Return value: A newly-created #CalFactory, or NULL if its corresponding CORBA
 * object could not be created.
 **/
CalFactory *
cal_factory_new (void)
{
	CalFactory *factory;
	CORBA_Environment ev;
	GNOME_Calendar_CalFactory corba_factory;
	gboolean retval;

	factory = gtk_type_new (CAL_FACTORY_TYPE);

	corba_factory = cal_factory_corba_object_create (GNOME_OBJECT (factory));

	CORBA_exception_init (&ev);
	retval = CORBA_Object_is_nil (corba_factory, &ev);

	if (ev._major != CORBA_NO_EXCEPTION || retval) {
		g_message ("cal_factory_new(): could not create the CORBA factory");
		gtk_object_unref (factory);
		CORBA_exception_free (&ev);
		return NULL;
	}
	CORBA_exception_free (&ev);

	return cal_factory_construct (factory, corba_factory);
}

void
cal_factory_load (CalFactory *factory, const char *uri, GNOME_Calendar_Listener listener)
{
	LoadCreateJobData *jd;
	CORBA_Environment ev;
	GNOME_Calendar_Listener listener_copy;

	CORBA_exception_init (&ev);
	listener_copy = CORBA_Object_duplicate (listener, &ev);

	if (ev._major != CORBA_NO_EXCEPTION) {
		g_message ("cal_factory_load(): could not duplicate the listener");
		CORBA_exception_free (&ev);
		return;
	}

	CORBA_exception_free (&ev);

	jd = g_new (LoadCreateJobData, 1);
	jd->factory = factory;
	jd->uri = g_strdup (uri);
	jd->listener = listener_copy;

	job_add (load_fn, jd);
}

void
cal_factory_create (CalFactory *factory, const char *uri, GNOME_Calendar_Listener listener)
{
	/* FIXME */
}