lm-sistemi-software-distribuiti/src/main/kotlin/util/jms/requestor/AbstractRequestor.kt

package util.jms.requestor

import java.io.Serializable
import javax.jms.Message
import javax.jms.QueueConnectionFactory
import javax.jms.Session
import javax.jms.ObjectMessage
import javax.jms.TextMessage

abstract class AbstractRequestor(
    queueName: String,
    private val shared: Boolean = false
) : Requestor {
    private val connectionFactory: QueueConnectionFactory = this.getFactory()
    private val connection = connectionFactory.createQueueConnection()
        .also { it.start() }
    private val mainSession = connection.createQueueSession(
        false,
        Session.AUTO_ACKNOWLEDGE
    )
    private val queue = mainSession.createQueue(queueName)
    private val sender = mainSession.createSender(queue)
    private val secondarySession = connection.createQueueSession(
        false,
        Session.AUTO_ACKNOWLEDGE
    )
    private val replyQueue = secondarySession.createTemporaryQueue()
    private var receiver = if (!shared) secondarySession.createReceiver(replyQueue) else null

    override fun request(message: Message): Message {
        message.jmsReplyTo = replyQueue

        sender.send(message)

        if (shared)
            receiver = secondarySession.createReceiver(
                replyQueue,
                "JMSCorrelationID = '${message.jmsMessageID}'"
            )

        return receiver!!.receive()
    }

    override fun createTextMessage(text: String): TextMessage = mainSession.createTextMessage(text)

    override fun createObjectMessage(obj: Serializable?): ObjectMessage =
        mainSession.createObjectMessage(obj)

    override fun createMessage(): Message = mainSession.createMessage()

    override fun close() {
        mainSession.close()
        secondarySession.close()
        connection.close()
    }

    abstract fun getFactory(uri: String = "tcp://localhost:61616"): QueueConnectionFactory
}