/* diversity-viewport.c - DiversityViewport, a glance at the glorious world
 *
 * Copyright 2007-2008 OpenMoko, Inc.
 * Authored by Chia-I Wu <olv@openmoko.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 <glib.h>
#include <diversity-viewport.h>
#include "diversity-marshal.h"

enum {
	ENABLED,
	OBJECT_ADDED,
	OBJECT_REMOVED,
	OBJECT_CLEARED,
	FILTER_CHANGED,
	LAST_SIGNAL
};

#define DIVERSITY_VIEWPORT_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE((o), DIVERSITY_TYPE_VIEWPORT, DiversityViewportPrivate))
typedef struct _DiversityViewportPrivate DiversityViewportPrivate;
typedef struct _DiversityViewportRule DiversityViewportRule;

struct _DiversityViewportRule {
	DiversityObjectType type;
	gint mask;
	gint value;
};

struct _DiversityViewportPrivate {
	GSList *objects;

	gboolean enabled;

	DiversityViewportFilter filter;
	gpointer filter_data;

	DiversityViewportRule rule;
};

static guint viewport_signals[LAST_SIGNAL] = { 0 };

G_DEFINE_TYPE(DiversityViewport, diversity_viewport, DIVERSITY_TYPE_OBJECT);

static void on_object_geometry_changed(DiversityObject *obj, gdouble lon, gdouble lat, gdouble width, gdouble height, gpointer data);

static void diversity_viewport_dispose(GObject *obj)
{
	DiversityViewport *view = DIVERSITY_VIEWPORT(obj);
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);
	GSList *tmp_list;
	
	tmp_list = priv->objects;
	while (tmp_list) {
		g_signal_handlers_disconnect_by_func(tmp_list->data,
				on_object_geometry_changed, view);
		g_object_unref(tmp_list->data);
		tmp_list = tmp_list->next;
	}

	((GObjectClass *) diversity_viewport_parent_class)->dispose(obj);
}

static void diversity_viewport_finalize(GObject *obj)
{
	DiversityViewport *view = DIVERSITY_VIEWPORT(obj);
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	g_slist_free(priv->objects);
	priv->objects = NULL;

	((GObjectClass *) diversity_viewport_parent_class)->finalize(obj);
}

static void diversity_viewport_filter_changed(DiversityViewport *view)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);
	GSList *tmp_list;
	
	if (!priv->filter)
		return;

	tmp_list = priv->objects;

	while (tmp_list) {
		DiversityObject *obj = tmp_list->data;

		tmp_list = tmp_list->next;

		if (!priv->filter(view, obj, priv->filter_data))
			diversity_viewport_remove_object(view, obj);
	}
}

static void diversity_viewport_class_init(DiversityViewportClass *klass)
{
	GObjectClass *o_class = (GObjectClass *) klass;

	o_class->dispose = diversity_viewport_dispose;
	o_class->finalize = diversity_viewport_finalize;

	klass->filter_changed = diversity_viewport_filter_changed;

	g_type_class_add_private(klass, sizeof(DiversityViewportPrivate));

	viewport_signals[ENABLED] =
		g_signal_new("enabled",
			     G_TYPE_FROM_CLASS(klass),
			     G_SIGNAL_RUN_LAST,
			     G_STRUCT_OFFSET(DiversityViewportClass, enabled),
			     NULL, NULL,
			     g_cclosure_marshal_VOID__BOOLEAN,
			     G_TYPE_NONE, 1,
			     G_TYPE_BOOLEAN);

	viewport_signals[OBJECT_ADDED] =
		g_signal_new("object-added",
			     G_TYPE_FROM_CLASS(klass),
			     G_SIGNAL_RUN_LAST,
			     G_STRUCT_OFFSET(DiversityViewportClass, object_added),
			     NULL, NULL,
			     g_cclosure_marshal_VOID__OBJECT,
			     G_TYPE_NONE, 1,
			     G_TYPE_OBJECT);

	viewport_signals[OBJECT_REMOVED] =
		g_signal_new("object-removed",
			     G_TYPE_FROM_CLASS(klass),
			     G_SIGNAL_RUN_LAST,
			     G_STRUCT_OFFSET(DiversityViewportClass, object_removed),
			     NULL, NULL,
			     g_cclosure_marshal_VOID__OBJECT,
			     G_TYPE_NONE, 1,
			     G_TYPE_OBJECT);

	viewport_signals[OBJECT_CLEARED] =
		g_signal_new("object-cleared",
			     G_TYPE_FROM_CLASS(klass),
			     G_SIGNAL_RUN_LAST,
			     G_STRUCT_OFFSET(DiversityViewportClass, object_cleared),
			     NULL, NULL,
			     g_cclosure_marshal_VOID__VOID,
			     G_TYPE_NONE, 0);

	viewport_signals[FILTER_CHANGED] =
		g_signal_new("filter-changed",
			     G_TYPE_FROM_CLASS(klass),
			     G_SIGNAL_RUN_LAST,
			     G_STRUCT_OFFSET(DiversityViewportClass, filter_changed),
			     NULL, NULL,
			     g_cclosure_marshal_VOID__VOID,
			     G_TYPE_NONE, 0);
}

static void diversity_viewport_init(DiversityViewport *view)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	DIVERSITY_OBJECT(view)->type = DIVERSITY_OBJECT_TYPE_VIEWPORT;
	priv->objects = NULL;
	priv->enabled = FALSE;
	priv->filter = NULL;
}

static void on_viewport_geometry_changed(DiversityViewport *view, gdouble lon, gdouble lat, gdouble width, gdouble height, gpointer data)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);
	GSList *tmp_list = priv->objects;

	while (tmp_list) {
		DiversityObject *obj = tmp_list->data;

		tmp_list = tmp_list->next;

		if (!diversity_object_intersect((DiversityObject *) view, obj))
			diversity_viewport_remove_object(view, obj);
	}
}

static void on_object_geometry_changed(DiversityObject *obj, gdouble lon, gdouble lat, gdouble width, gdouble height, gpointer data)
{
	DiversityViewport *view = data;

	if (!diversity_object_intersect((DiversityObject *) view, obj))
		diversity_viewport_remove_object(view, obj);
}

DiversityViewport *diversity_viewport_new(gdouble lon1, gdouble lat1, gdouble lon2, gdouble lat2)
{
	DiversityObject *view;

	if (lon1 > lon2 || lat1 > lat2)
		return NULL;

	view = g_object_new(DIVERSITY_TYPE_VIEWPORT, NULL);
	diversity_object_geometry_set(view, lon1, lat1, lon2 - lon1, lat2 - lat1);

	g_signal_connect(view, "geometry_changed",
			 G_CALLBACK(on_viewport_geometry_changed), NULL);

	return (DiversityViewport *) view;
}

gboolean diversity_viewport_add_object(DiversityViewport *view, DiversityObject *obj)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	if (!priv->enabled)
		return FALSE;

	if (priv->filter && !priv->filter(view, obj, priv->filter_data))
		return FALSE;

	if (!diversity_object_intersect((DiversityObject *) view, obj))
		return FALSE;

	if (g_slist_find(priv->objects, obj))
		return FALSE;

	g_signal_connect(obj, "geometry_changed",
			 G_CALLBACK(on_object_geometry_changed), view);

	priv->objects = g_slist_prepend(priv->objects, obj);
	g_object_ref(obj);

	diversity_viewport_get_objects(view);

	g_signal_emit(view, viewport_signals[OBJECT_ADDED], 0, obj);

	return TRUE;
}

void diversity_viewport_remove_object(DiversityViewport *view, DiversityObject *obj)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);
	GSList *tmp;

	tmp = g_slist_find(priv->objects, obj);
	if (!tmp)
		return;

	g_signal_handlers_disconnect_by_func(obj, on_object_geometry_changed, view);
	priv->objects = g_slist_delete_link(priv->objects, tmp);

	g_object_unref(obj);

	g_signal_emit(view, viewport_signals[OBJECT_REMOVED], 0, obj);
}

void diversity_viewport_set_filter(DiversityViewport *view, DiversityViewportFilter filter, gpointer data)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	priv->filter = filter;
	priv->filter_data = data;

	g_signal_emit(view, viewport_signals[FILTER_CHANGED], 0);
}

static gboolean rule_filter(DiversityViewport *view, DiversityObject *obj, gpointer data)
{
	DiversityViewportRule *rule = data;
	guint flags;

	flags = diversity_object_get_flags(obj);

	return (obj->type == rule->type && (flags & rule->mask) == rule->value);
}

void diversity_viewport_set_rule(DiversityViewport *view, DiversityObjectType type, gint mask, gint value)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	priv->rule.type = type;
	priv->rule.mask = mask;
	priv->rule.value = value & mask;

	diversity_viewport_set_filter(view, rule_filter, &priv->rule);
}

void diversity_viewport_clear_objects(DiversityViewport *view)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);
	GSList *tmp_list = priv->objects;

	while (tmp_list) {
		g_signal_handlers_disconnect_by_func(tmp_list->data,
				on_object_geometry_changed, view);
		g_object_unref(tmp_list->data);
		tmp_list = tmp_list->next;
	}

	g_slist_free(priv->objects);
	priv->objects = NULL;

	g_signal_emit(view, viewport_signals[OBJECT_CLEARED], 0);
}

guint diversity_viewport_count_objects(DiversityViewport *view)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	return g_slist_length(priv->objects);
}

const GSList *diversity_viewport_get_objects(DiversityViewport *view)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	return priv->objects;
}

void diversity_viewport_set_enabled(DiversityViewport *view, gboolean enabled)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	if (priv->enabled != enabled) {
		priv->enabled = enabled;

		g_signal_emit(view, viewport_signals[ENABLED], 0, enabled);

		if (!enabled)
			diversity_viewport_clear_objects(view);
	}
}

gboolean diversity_viewport_get_enabled(DiversityViewport *view)
{
	DiversityViewportPrivate *priv = DIVERSITY_VIEWPORT_GET_PRIVATE(view);

	return priv->enabled;
}