/*
 *
 *  neard - Near Field Communication manager
 *
 *  Copyright (C) 2012  Intel Corporation. All rights reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>

#include <glib.h>

#include <gdbus.h>

#include "near.h"

static DBusConnection *connection = NULL;
static GHashTable *ndef_app_hash;

struct near_ndef_agent {
	char *sender;
	char *path;
	char *record_type;
	guint watch;
};

static void ndef_agent_free(gpointer data)
{
	DBusMessage *message;
	struct near_ndef_agent *agent = data;

	DBG("");

	if (agent == NULL)
		return;

	DBG("%s %s %s", agent->sender, agent->path, NFC_NDEF_AGENT_INTERFACE);

	message = dbus_message_new_method_call(agent->sender, agent->path,
					NFC_NDEF_AGENT_INTERFACE, "Release");
	if (message == NULL)
		return;

	dbus_message_set_no_reply(message, TRUE);

	g_dbus_send_message(connection, message);

	g_dbus_remove_watch(connection, agent->watch);

	g_free(agent->sender);
	g_free(agent->path);
}

static void ndef_agent_disconnect(DBusConnection *conn, void *user_data)
{
	struct near_ndef_agent *agent = user_data;

	DBG("agent %s disconnected", agent->path);

	g_hash_table_remove(ndef_app_hash, agent->record_type);
}

static void append_record_path(DBusMessageIter *iter, void *user_data)
{
	GList *records = user_data, *list;
	struct near_ndef_record *record;
	char *path;

	for (list = records; list; list = list->next) {
		record = list->data;

		path = __near_ndef_record_get_path(record);
		if (path == NULL)
			continue;

		dbus_message_iter_append_basic(iter,
					DBUS_TYPE_STRING, &path);
	}
}

static void ndef_agent_push_records(struct near_ndef_agent *agent,
							GList *records)
{
	DBusMessageIter iter, dict;
	DBusMessage *message;

	DBG("");

	if (agent->sender == NULL || agent->path == NULL)
		return;

	DBG("Sending NDEF to %s %s", agent->path, agent->sender);

	message = dbus_message_new_method_call(agent->sender, agent->path,
					NFC_NDEF_AGENT_INTERFACE,
					"GetNDEF");
	if (message == NULL)
		return;

	dbus_message_iter_init_append(message, &iter);

	near_dbus_dict_open(&iter, &dict);
	near_dbus_dict_append_array(&dict, "Records",
				DBUS_TYPE_STRING, append_record_path, records);
	near_dbus_dict_close(&iter, &dict);

	DBG("sending...");

	dbus_message_set_no_reply(message, TRUE);

	g_dbus_send_message(connection, message);
}

void __near_agent_ndef_parse_records(GList *records)
{
	GList *list;
	struct near_ndef_record *record;
	struct near_ndef_agent *agent;
	char *type;

	DBG("");

	for (list = records, agent = NULL; list; list = list->next) {
		record = list->data;
		type  = __near_ndef_record_get_type(record);

		DBG("Looking for type %s", type);

		agent = g_hash_table_lookup(ndef_app_hash, type);
		if (agent != NULL)
			break;
	}

	if (agent == NULL)
		return;

	ndef_agent_push_records(agent, records);

	return;
}

int __near_agent_ndef_register(const char *sender, const char *path,
						const char *record_type)
{
	struct near_ndef_agent *agent;

	DBG("%s registers path %s for %s", sender, path, record_type);

	if (g_hash_table_lookup(ndef_app_hash, record_type) != NULL)
		return -EEXIST;

	agent = g_try_malloc0(sizeof(struct near_ndef_agent));
	if (agent == NULL)
		return -ENOMEM;

	agent->sender = g_strdup(sender);
	agent->path = g_strdup(path);
	agent->record_type = g_strdup(record_type);
	
	if (agent->sender == NULL || agent->path == NULL ||
	    agent->record_type == NULL) {
		g_free(agent);
		return -ENOMEM;
	}

	agent->watch = g_dbus_add_disconnect_watch(connection, sender,
						ndef_agent_disconnect, agent, NULL);
	g_hash_table_insert(ndef_app_hash, agent->record_type, agent);

	return 0;
}

int __near_agent_ndef_unregister(const char *sender, const char *path,
						const char *record_type)
{
	struct near_ndef_agent *agent;

	DBG("sender %s path %s type %s", sender, path, record_type);

	agent = g_hash_table_lookup(ndef_app_hash, record_type);
	if (agent == NULL)
		return -EINVAL;

	if (strcmp(agent->path, path) != 0 || strcmp(agent->sender, sender) != 0)
		return -EINVAL;

	g_hash_table_remove(ndef_app_hash, record_type);

	return 0;
}

static guint handover_agent_watch = 0;
static gchar *handover_agent_path = NULL;
static gchar *handover_agent_sender = NULL;

static void handover_agent_free(void)
{
	if (handover_agent_watch > 0) {
		g_dbus_remove_watch(connection, handover_agent_watch);
		handover_agent_watch = 0;
	}

	g_free(handover_agent_sender);
	handover_agent_sender = NULL;

	g_free(handover_agent_path);
	handover_agent_path = NULL;
}

static void handover_agent_disconnect(DBusConnection *conn, void *data)
{
	DBG("data %p", data);

	handover_agent_watch = 0;

	handover_agent_free();
}

static void handover_agent_release(void)
{
	DBusMessage *message;

	if (handover_agent_watch == 0)
		return;

	message = dbus_message_new_method_call(handover_agent_sender,
						handover_agent_path,
						"org.neard.HandoverAgent",
						"Release");
	if (message != NULL)
		g_dbus_send_message(connection, message);

	handover_agent_free();
}

int __near_agent_handover_register(const char *sender, const char *path)
{
	DBG("sender %s path %s", sender, path);

	if (handover_agent_path != NULL)
		return -EEXIST;

	handover_agent_watch = g_dbus_add_disconnect_watch(connection, sender,
					handover_agent_disconnect, NULL, NULL);
	if (handover_agent_watch == 0)
		return -ENOMEM;

	handover_agent_sender = g_strdup(sender);
	handover_agent_path = g_strdup(path);

	return 0;
}

int __near_agent_handover_unregister(const char *sender, const char *path)
{
	DBG("sender %s path %s", sender, path);

	if (handover_agent_path == NULL)
		return -ESRCH;

	handover_agent_free();

	return 0;
}

int __near_agent_init(void)
{
	DBG("");

	connection = near_dbus_get_connection();
	if (connection == NULL)
		return -1;

	ndef_app_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
						g_free, ndef_agent_free);

	return 0;
}

void __near_agent_cleanup(void)
{
	DBG("");

	g_hash_table_destroy(ndef_app_hash);
	ndef_app_hash = NULL;

	handover_agent_release();

	dbus_connection_unref(connection);
}