package main

import (
	"encoding/json"
	"log"

	amqp "github.com/rabbitmq/amqp091-go"
)

type UpdateHandler interface {
	OrderPlaced(order Order)
}

type RabbitTransportClient struct {
	Url string

	OrderTopic string
	ClientName string
	handler    UpdateHandler
	connection *amqp.Connection
	channel    *amqp.Channel
	quit       chan bool
}

func (t *RabbitTransportClient) declareBindAndConsume(topic string) (<-chan amqp.Delivery, error) {
	q, err := t.channel.QueueDeclare(
		"orders", // name
		false,    // durable
		false,    // delete when unused
		true,     // exclusive
		false,    // no-wait
		nil,      // arguments
	)
	if err != nil {
		return nil, err
	}
	err = t.channel.QueueBind(q.Name, topic, topic, false, nil)
	if err != nil {
		return nil, err
	}
	return t.channel.Consume(
		q.Name,
		"",
		true,
		false,
		false,
		false,
		nil,
	)
}

func (t *RabbitTransportClient) Connect(handler UpdateHandler) error {
	conn, err := amqp.DialConfig(t.Url, amqp.Config{
		Properties: amqp.NewConnectionProperties(),
	})
	//conn.Config.Vhost = t.VHost
	t.quit = make(chan bool)
	if err != nil {
		return err
	}
	t.connection = conn
	ch, err := conn.Channel()
	if err != nil {
		return err
	}
	t.handler = handler
	t.channel = ch
	toAdd, err := t.declareBindAndConsume(t.OrderTopic)
	if err != nil {
		return err
	}
	log.Printf("Connected to rabbit upsert topic: %s", t.OrderTopic)
	go func(msgs <-chan amqp.Delivery) {
		for d := range msgs {

			var order Order
			if err := json.Unmarshal(d.Body, &order); err == nil {
				log.Printf("Got order")
				t.handler.OrderPlaced(order)
			} else {
				log.Printf("Failed to unmarshal upset message %v", err)
			}
		}
	}(toAdd)

	return nil
}

func (t *RabbitTransportClient) Close() {
	if (t.channel != nil) && (!t.channel.IsClosed()) {
		t.channel.Close()
	}
	if (t.connection != nil) && (!t.connection.IsClosed()) {
		t.connection.Close()
	}
	//t.quit <- true

}