/*

 * gnome-keyring

 *

 * Copyright (C) 2011 Collabora Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as

 * published by the Free Software Foundation; either version 2.1 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this program; if not, see <http://www.gnu.org/licenses/>.

 *

 * Author: Stef Walter <stefw@collabora.co.uk>

 */

#include "config.h"

#include "gcr-collection.h"

#include "gcr-internal.h"

#include "gcr-union-collection.h"

#include <string.h>

/**

 * SECTION:gcr-union-collection

 * @title: GcrUnionCollection

 * @short_description: A GcrCollection which combines other collections

 *

 * An implementation of #GcrCollection, which combines the objects in

 * other #GcrCollections. Use gcr_union_collection_add() to add and

 * gcr_union_collection_remove() to remove them.

 */

/**

 * GcrUnionCollection:

 *

 * A union implementation of #GcrCollection.

 */

/**

 * GcrUnionCollectionClass:

 * @parent_class: The parent class

 *

 * The class for #GcrUnionCollection.

 */

struct _GcrUnionCollectionPrivate {

	GHashTable *items;

	GHashTable *collections;

};

static void      gcr_collection_iface       (GcrCollectionIface *iface);

G_DEFINE_TYPE_WITH_CODE (GcrUnionCollection, gcr_union_collection, G_TYPE_OBJECT,

                         G_IMPLEMENT_INTERFACE (GCR_TYPE_COLLECTION, gcr_collection_iface));

static void

on_collection_added (GcrCollection *collection,

                     GObject *object,

                     gpointer user_data)

{

	GcrUnionCollection *self = GCR_UNION_COLLECTION (user_data);

	gint *count;

	g_object_ref (object);

	count = g_hash_table_lookup (self->pv->items, object);

	if (count == NULL) {

		count = g_new0 (gint, 1);

		*count = 1;

		g_hash_table_insert (self->pv->items, object, count);

		gcr_collection_emit_added (GCR_COLLECTION (self), object);

	} else {

		g_assert (*count > 0);

		(*count)++;

	}

	g_object_unref (object);

}

static void

on_collection_removed (GcrCollection *collection,

                       GObject *object,

                       gpointer user_data)

{

	GcrUnionCollection *self = GCR_UNION_COLLECTION (user_data);

	gint *count;

	g_object_ref (object);

	count = g_hash_table_lookup (self->pv->items, object);

	if (count != NULL) {

		g_assert (*count > 0);

		(*count)--;

		if (*count == 0) {

			g_hash_table_remove (self->pv->items, object);

			gcr_collection_emit_removed (GCR_COLLECTION (self), object);

		}

	} else {

		g_warning ("Object of type %s that exists in an underlying "

		           "collection of a GcrUnionCollection appeared without "

		           "emitting 'added' signal.", G_OBJECT_TYPE_NAME (object));

	}

	g_object_unref (object);

}

static void

connect_to_collection (GcrUnionCollection *self,

                       GcrCollection *collection)

{

	g_signal_connect (collection, "added", G_CALLBACK (on_collection_added), self);

	g_signal_connect (collection, "removed", G_CALLBACK (on_collection_removed), self);

}

static void

disconnect_from_collection (GcrUnionCollection *self,

                            GcrCollection *collection)

{

	g_signal_handlers_disconnect_by_func (collection, on_collection_added, self);

	g_signal_handlers_disconnect_by_func (collection, on_collection_removed, self);

}

static void

gcr_union_collection_init (GcrUnionCollection *self)

{

	self->pv = G_TYPE_INSTANCE_GET_PRIVATE (self, GCR_TYPE_UNION_COLLECTION, GcrUnionCollectionPrivate);

	self->pv->items = g_hash_table_new_full (g_direct_hash, g_direct_equal,

	                                         NULL, g_free);

	self->pv->collections = g_hash_table_new_full (g_direct_hash, g_direct_equal,

	                                               g_object_unref, NULL);

}

static void

gcr_union_collection_dispose (GObject *obj)

{

	GcrUnionCollection *self = GCR_UNION_COLLECTION (obj);

	GHashTableIter iter;

	GcrCollection *collection;

	g_hash_table_iter_init (&iter, self->pv->collections);

	while (g_hash_table_iter_next (&iter, (gpointer *)&collection, NULL))

		disconnect_from_collection (self, collection);

	g_hash_table_remove_all (self->pv->collections);

	g_hash_table_remove_all (self->pv->items);

	G_OBJECT_CLASS (gcr_union_collection_parent_class)->dispose (obj);

}

static void

gcr_union_collection_finalize (GObject *obj)

{

	GcrUnionCollection *self = GCR_UNION_COLLECTION (obj);

	g_assert (g_hash_table_size (self->pv->items) == 0);

	g_hash_table_destroy (self->pv->items);

	g_assert (g_hash_table_size (self->pv->collections) == 0);

	g_hash_table_destroy (self->pv->collections);

	G_OBJECT_CLASS (gcr_union_collection_parent_class)->finalize (obj);

}

static void

gcr_union_collection_class_init (GcrUnionCollectionClass *klass)

{

	GObjectClass *gobject_class = G_OBJECT_CLASS (klass);

	gobject_class->dispose = gcr_union_collection_dispose;

	gobject_class->finalize = gcr_union_collection_finalize;

	g_type_class_add_private (gobject_class, sizeof (GcrUnionCollectionPrivate));

}

static guint

gcr_union_collection_real_get_length (GcrCollection *coll)

{

	GcrUnionCollection *self = GCR_UNION_COLLECTION (coll);

	return g_hash_table_size (self->pv->items);

}

static GList*

gcr_union_collection_real_get_objects (GcrCollection *coll)

{

	GcrUnionCollection *self = GCR_UNION_COLLECTION (coll);

	return g_hash_table_get_keys (self->pv->items);

}

static gboolean

gcr_union_collection_real_contains (GcrCollection *collection,

                                    GObject *object)

{

	GcrUnionCollection *self = GCR_UNION_COLLECTION (collection);

	return g_hash_table_lookup (self->pv->items, object) ? TRUE : FALSE;

}

static void

gcr_collection_iface (GcrCollectionIface *iface)

{

	iface->get_length = gcr_union_collection_real_get_length;

	iface->get_objects = gcr_union_collection_real_get_objects;

	iface->contains = gcr_union_collection_real_contains;

}

/* -----------------------------------------------------------------------------

 * PUBLIC

 */

/**

 * gcr_union_collection_new:

 *

 * Create a new #GcrUnionCollection.

 *

 * Returns: (transfer full) (type Gcr.UnionCollection): a newly allocated

 *          collection, which should be freed with g_object_unref()

 */

GcrCollection *

gcr_union_collection_new (void)

{

	return g_object_new (GCR_TYPE_UNION_COLLECTION, NULL);

}

/**

 * gcr_union_collection_add:

 * @self: The union collection

 * @collection: The collection whose objects to add

 *

 * Add objects from this collection to the union

 */

void

gcr_union_collection_add (GcrUnionCollection *self,

                          GcrCollection *collection)

{

	g_return_if_fail (GCR_IS_UNION_COLLECTION (self));

	g_return_if_fail (GCR_IS_COLLECTION (collection));

	gcr_union_collection_take (self, g_object_ref (collection));

}

/**

 * gcr_union_collection_take:

 * @self: The union collection

 * @collection: The collection whose objects to add

 *

 * Add objects from this collection to the union. Do not add an additional

 * reference to the collection.

 */

void

gcr_union_collection_take (GcrUnionCollection *self,

                           GcrCollection *collection)

{

	GList *objects, *l;

	g_return_if_fail (GCR_IS_UNION_COLLECTION (self));

	g_return_if_fail (GCR_IS_COLLECTION (collection));

	g_return_if_fail (!g_hash_table_lookup (self->pv->collections, collection));

	g_object_ref (collection);

	g_hash_table_insert (self->pv->collections, collection, collection);

	connect_to_collection (self, collection);

	objects = gcr_collection_get_objects (collection);

	for (l = objects; l != NULL; l = g_list_next (l))

		on_collection_added (collection, l->data, self);

	g_list_free (objects);

	g_object_unref (collection);

}

/**

 * gcr_union_collection_remove:

 * @self: The collection

 * @collection: The collection whose objects to remove

 *

 * Remove an object from the collection.

 */

void

gcr_union_collection_remove (GcrUnionCollection *self,

                             GcrCollection *collection)

{

	GList *objects, *l;

	g_return_if_fail (GCR_IS_UNION_COLLECTION (self));

	g_return_if_fail (GCR_IS_COLLECTION (collection));

	g_return_if_fail (g_hash_table_lookup (self->pv->collections, collection));

	g_object_ref (collection);

	g_hash_table_remove (self->pv->collections, collection);

	disconnect_from_collection (self, collection);

	objects = gcr_collection_get_objects (collection);

	for (l = objects; l != NULL; l = g_list_next (l))

		on_collection_removed (collection, l->data, self);

	g_list_free (objects);

	g_object_unref (collection);

}

/**

 * gcr_union_collection_have:

 * @self: the union collection

 * @collection: the collection to check

 *

 * Check whether the collection is present in the union.

 *

 * Returns: whether present or not

 */

gboolean

gcr_union_collection_have (GcrUnionCollection *self,

                           GcrCollection *collection)

{

	g_return_val_if_fail (GCR_IS_UNION_COLLECTION (self), FALSE);

	g_return_val_if_fail (GCR_IS_COLLECTION (collection), FALSE);

	return g_hash_table_lookup (self->pv->collections, collection) != NULL;

}

/**

 * gcr_union_collection_size:

 * @self: the union collection

 *

 * Return the number of collections in this union. This does not reflect

 * the number of objects in the combined collection.

 *

 * Returns: number of collections inlcuded

 */

guint

gcr_union_collection_size (GcrUnionCollection *self)

{

	g_return_val_if_fail (GCR_IS_UNION_COLLECTION (self), FALSE);

	return g_hash_table_size (self->pv->collections);

}

/**

 * gcr_union_collection_elements:

 * @self: the union collection

 *

 * Get the collections that have been added to this union.

 *

 * Returns: (element-type Gcr.Collection) (transfer container): collections

 *          added to the union

 */

GList *

gcr_union_collection_elements (GcrUnionCollection *self)

{

	g_return_val_if_fail (GCR_IS_UNION_COLLECTION (self), NULL);

	return g_hash_table_get_values (self->pv->collections);

}