/*
	PIP - Platform Independent Primitives
	MQTT Client
	Ivan Pelipenko peri4ko@yandex.ru

	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 3 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/>.
*/

#include "pimqttclient.h"

#include "MQTTClient.h"


STATIC_INITIALIZER_BEGIN
	MQTTClient_init_options opts = MQTTClient_init_options_initializer;
	MQTTClient_global_init(&opts);
STATIC_INITIALIZER_END


PRIVATE_DEFINITION_START(PIMQTT::Client)
	MQTTClient client = nullptr;
	bool connected    = false;

	static void connectionLost_callback(void * context, char *) {
		((PIMQTT::Client *)context)->mqtt_connectionLost();
	}

	static void deliveryComplete_callback(void * context, MQTTClient_deliveryToken dt) {
		((PIMQTT::Client *)context)->mqtt_deliveryComplete(dt);
	}

	static int messageArrived_callback(void * context, char * topicName, int topicLen, MQTTClient_message * message) {
		PIMQTT::MessageMutable msg;
		msg.setTopic(PIString::fromUTF8(topicName));
		msg.setPayload(PIByteArray(message->payload, message->payloadlen));
		msg.setID(message->msgid);
		msg.setDuplicate(message->dup != 0);
		msg.setQos(static_cast<PIMQTT::QoS>(message->qos));
		MQTTClient_freeMessage(&message);
		MQTTClient_free(topicName);
		((PIMQTT::Client *)context)->mqtt_messageArrived(msg);
		return 1;
	}

PRIVATE_DEFINITION_END(PIMQTT::Client)


PIMQTT::Client::Client() {
	worker = new PIThreadPoolWorker(1);
	worker->start();
}


PIMQTT::Client::~Client() {
	is_destoying = true;
	worker->clearTasks();
	disconnect();
	worker->waitForTasks();
	worker->stopAndWait();
	piDeleteSafety(worker);
}


void PIMQTT::Client::connect(const PIString & address, const PIString & client, const PIString & username, const PIString & password) {
	if (is_destoying) return;
	ConnectInfo ci;
	ci.address  = address;
	ci.clientID = client;
	ci.username = username;
	ci.password = password;
	worker->enqueueTask([this, ci] { connectInternal(ci); });
}


void PIMQTT::Client::disconnect() {
	worker->enqueueTask([this] { disconnectInternal(); });
}


void PIMQTT::Client::subscribe(const PIString & topic, QoS qos) {
	if (is_destoying) return;
	worker->enqueueTask([this, topic, qos] { subscribeInternal({topic, qos}); });
}


void PIMQTT::Client::unsubscribe(const PIString & topic) {
	if (is_destoying) return;
	worker->enqueueTask([this, topic] { unsubscribeInternal(topic); });
}


void PIMQTT::Client::publish(const PIString & topic, const PIByteArray & msg, QoS qos) {
	MessageMutable m;
	m.setTopic(topic);
	m.setPayload(msg);
	m.setQos(qos);
	publish(m);
}


void PIMQTT::Client::publish(const MessageConst & msg) {
	if (is_destoying) return;
	worker->enqueueTask([this, msg] { publishInternal(msg); });
}


void PIMQTT::Client::mqtt_connectionLost() {
	piCoutObj << "mqtt_connectionLost";
	PRIVATE->connected = false;
	changeStatus(Idle);
	disconnected(Error::ServerUnavailable);
}


void PIMQTT::Client::mqtt_deliveryComplete(int token) {}


void PIMQTT::Client::mqtt_messageArrived(const MessageConst & msg) {
	piCoutObj << "mqtt_messageArrived";
	received(msg);
}


void PIMQTT::Client::connectInternal(const ConnectInfo & ci) {
	destroy();
	changeStatus(Connecting);
	PRIVATE->connected        = false;
	PINetworkAddress net_addr = PINetworkAddress::resolve(ci.address);
	if (net_addr.port() == 0) net_addr.setPort(1883);
	PIString server_uri = "tcp://" + net_addr.toString();
	MQTTClient_create(&PRIVATE->client, server_uri.dataAscii(), ci.clientID.dataUTF8(), MQTTCLIENT_PERSISTENCE_NONE, nullptr);
	MQTTClient_setCallbacks(PRIVATE->client,
							this,
							PRIVATE->connectionLost_callback,
							PRIVATE->messageArrived_callback,
							PRIVATE->deliveryComplete_callback);
	MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer;
	conn_opts.keepAliveInterval         = 9;
	conn_opts.cleansession              = 1;
	conn_opts.connectTimeout            = piRound(connect_timeout.toSeconds());
	if (ci.username.isNotEmpty()) conn_opts.username = ci.username.dataAscii();
	if (ci.password.isNotEmpty()) conn_opts.password = ci.password.dataAscii();
	int ret = MQTTClient_connect(PRIVATE->client, &conn_opts);
	if (ret != MQTTCLIENT_SUCCESS) {
		piCoutObj << "Failed to connect to " + server_uri << ", code" << ret;
		changeStatus(Idle);
		if (ret < 0) ret = static_cast<int>(Error::ServerUnavailable);
		disconnected(static_cast<Error>(ret));
		return;
	}
	PRIVATE->connected = true;
	changeStatus(Connected);
	connected();
}


inline void PIMQTT::Client::disconnectInternal() {
	bool was_connected = PRIVATE->connected;
	changeStatus(Idle);
	destroy();
	if (was_connected) disconnected(Error::Unknown);
	PRIVATE->connected = false;
}


void PIMQTT::Client::publishInternal(const MessageConst & m) {
	if (!PRIVATE->client) return;
	MQTTClient_message pubmsg = MQTTClient_message_initializer;
	pubmsg.payload            = const_cast<void *>(static_cast<const void *>(m.payload().data()));
	pubmsg.payloadlen         = m.payload().size_s();
	pubmsg.qos                = static_cast<int>(m.qos());
	int ret                   = MQTTClient_publishMessage(PRIVATE->client, m.topic().dataAscii(), &pubmsg, nullptr);
	if (ret != MQTTCLIENT_SUCCESS) {
		piCoutObj << "Failed to publishMessage, code" << ret;
	}
}


void PIMQTT::Client::subscribeInternal(const Subscribe & sub) {
	if (!PRIVATE->client) return;
	int ret = MQTTClient_subscribe(PRIVATE->client, sub.topic.dataUTF8(), static_cast<int>(sub.qos));
	if (ret != MQTTCLIENT_SUCCESS) {
		piCoutObj << "Failed to subscribe" << sub.topic << ", code" << ret;
	}
}


void PIMQTT::Client::unsubscribeInternal(const PIString & topic) {
	if (!PRIVATE->client) return;
	int ret = MQTTClient_unsubscribe(PRIVATE->client, topic.dataUTF8());
	if (ret != MQTTCLIENT_SUCCESS) {
		piCoutObj << "Failed to unsubscribe" << topic << ", code" << ret;
	}
}


void PIMQTT::Client::destroy() {
	if (!PRIVATE->client) return;
	if (PRIVATE->connected) MQTTClient_disconnect(PRIVATE->client, 1000);
	MQTTClient_destroy(&PRIVATE->client);
	PRIVATE->connected = false;
	PRIVATE->client    = nullptr;
}


void PIMQTT::Client::changeStatus(Status s) {
	m_status = s;
}