class Mqtt {
    /**
     * Connect to MQTT server.
     */
    static connect() {
        // make an api call to get the mqtt info
        this.connected = false;
        this.subscribes = {};
        Core.API.call({
            url: `/api/${Page.Meta.api_version}/server/configuration/index.php`,
            data: {
                func: 'apiGetMqttConnectionInfo'
            },
            callback: (data) => {
                setTimeout(
                    () => {
                        this.client = new Paho.MQTT.Client(data.mqtt_uri, Page.Meta.page_id);
                        this.client.onMessageArrived = (message) => this.onMessageArrived(message);
                        this.client.connect({
                            userName: data.mqtt_username,
                            password: data.mqtt_password,
                            useSSL: true,
                            onSuccess: () => this.onConnected(),
                            onFailure: () => this.reconnect()
                        });
                        this.client.onConnectionLost = (error) => {
                            this.onConnectionLost();
                            console.log(error);
                        };
                    },
                    1000
                );
            },
            fadeParameters: {
                hideLoader: true
            }
        });
    }
    /**
     * Reconnect MQTT.
     */
    static reconnect() {
        this.reconnectInterval = setInterval(
            () => Mqtt.connect(),
            5000
        );
    }
    /**
     * Process connection success.
     */
    static onConnected() {
        if (this.reconnectInterval) {
            clearInterval(this.reconnectInterval);
            this.reconnectInterval = null;
        }
        this.connected = true
        console.info('MQTT connected.');
        for (let context in this.subscribes) {
            for (let topic in this.subscribes[context]) {
                console.info(`Subscribing to ${topic}`);
                this.client.subscribe(
                    topic,
                    {
                        qos: 2,
                        onFailure: (invocationContext, errorCode, errorMessage) => console.error(`Failed to subscribe to ${topic}: ${errorMessage}`)
                    }
                );
            }
        }
    }
    /**
     * Process received message.
     * @param {object} message
     */
    static onMessageArrived(message) {
        for (let context in this.subscribes) {
            if (this.subscribes[context][message.destinationName]) {
                this.subscribes[context][message.destinationName](message);
            }
        }
    }
    /**
     * Process connection lost.
     */
    static onConnectionLost() {
        this.connected = false;
        this.reconnect();
    }
    /**
     * Subscribe to topic.
     * @param {string} context
     * @param {string} topic
     * @param {callable} callback
     */
    static subscribe(context, topic, callback) {
        if (!(context in this.subscribes)) {
            this.subscribes[context] = {};
        }
        this.subscribes[context][topic] = callback;
        if (this.connected) {
            console.info(`Subscribing to ${topic}`);
            this.client.subscribe(topic,
                {
                    qos: 2,
                    onFailure: (invocationContext, errorCode, errorMessage) => console.error(`Failed to subscribe to ${topic}: ${errorMessage}`)
                });
        }
    }
    /**
     * Unsubscribe to topic.
     * @param {string} context
     * @param {string} topic
     */
    static unsubscribe(context, topic) {
        if (!(context in this.subscribes)) {
            return;
        }
        if (!(topic in this.subscribes[context])) {
            return;
        }
        this.client.subscribe(
            topic,
            {
                onFailure: (invocationContext, errorCode, errorMessage) => console.error(`Failed to unsubscribe to ${topic}: ${errorMessage}`)
            }
        );

        console.info(`MQTT: Unsubscribing ${context}:${topic}`);

        delete this.subscribes[context][topic];
        if (_.isEmpty(this.subscribes[context])) {
            delete this.subscribes[context];
        }
    }
    /**
     * Unsubscribe all topics from context.
     * @param {string} context
     */
    static unsubscribeContext(context) {
        if (!(context in this.subscribes)) {
            return;
        }
        for (let topic in this.subscribes[context]) {
            this.unsubscribe(
                context,
                topic
            );
        }
    }
    /**
     * Publish MQTT message
     */
    static publish(topic, data) {
        let message = new Paho.MQTT.Message(data);
        message.destinationName = topic;
        message.qos = 2;
        this.client.send(message);
    }
}