package mqtt

import (
	"fmt"
	"net/url"
	"time"

	"github.com/eclipse/paho.mqtt.golang"

	"cygnux.net/kepler/config"
)

type Broker interface {
	mqtt.Client
}

type broker struct {
	mqtt.Client
}

func SetupBroker(cfg config.Config) (Broker, error) {
	var opts = mqtt.NewClientOptions()
	if svr := cfg.GetString("server"); svr != "" {
		if _, e := url.Parse(svr); nil != e {
			return nil, e
		} else {
			opts.AddBroker(svr)
		}
	} else if svrs := cfg.GetStringSlice("servers"); len(svrs) > 0 {
		for _, svr := range svrs {
			if _, e := url.Parse(svr); nil != e {
				return nil, e
			} else {
				opts.AddBroker(svr)
			}
		}
	} else {
		return nil, fmt.Errorf(" server or servers should be provided")
	}
	opts.SetClientID(cfg.GetString("clientId"))
	if s := cfg.GetString("username"); s != "" {
		opts.SetUsername(s)
	}
	if s := cfg.GetString("password"); s != "" {
		opts.SetPassword(s)
	}
	if d := cfg.GetDuration("keepAlive"); d > time.Second {
		opts.SetKeepAlive(d)
	}
	client := mqtt.NewClient(opts)
	return broker{Client: client}, nil
}