vergissberlin / mqtt-resource

module.exports = (input, callback) => {

	const mqtt = require('mqtt')

	const configuration = require('./configuration')

	const validate = require('./validate')

	let error = null

	let output = null

	validate.sourceConfiguration(input, (validatedInput, thrownError) => {

		input = validatedInput

		error = thrownError

	})

	validate.paramConfiguration(input, (validatedInput, thrownError) => {

		input = validatedInput

		error = thrownError

	})

	// Send MQTT

	if ( !error ) {

		let configurationMqtt = configuration.mqtt(input)

		let client = mqtt.connect(input.source.url, configurationMqtt)

		client.on('connect', () => {

			client.subscribe(input.source.topic, (errorConnection) => {

				if ( !errorConnection ) {

					client.publish(input.source.topic, input.params.payload, {

						qos: input.params.qos,

						retain: false

					})

				} else {

					error = errorConnection

				}

			})

		})

		client.on('message', (topic, message) => {

			output = {

				'version': {'ref': 'output'},

				'metadata': [

					{'name': 'message', 'value': input.params.payload.toString()},

					{'name': 'receivedMessage', 'value': message.toString()},

					{'name': 'qos', 'value': input.params.qos.toString()},

					{'name': 'timestamp', 'value': Date.now().toString()},

					{'name': 'topic', 'value': topic}

				]

			}

			client.end()

		})

		callback(error, output)

	}

}