package xmpp

import (
	"github.com/pkg/errors"
	"strconv"
	"strings"

	"dev.narayana.im/narayana/telegabber/persistence"
	"dev.narayana.im/narayana/telegabber/xmpp/gateway"

	log "github.com/sirupsen/logrus"
	"gosrc.io/xmpp"
	"gosrc.io/xmpp/stanza"
)

func logPacketType(p stanza.Packet) {
	log.Warnf("Ignoring packet: %T\n", p)
}

// HandleIq processes an incoming XMPP iq
func HandleIq(s xmpp.Sender, p stanza.Packet) {
	iq, ok := p.(stanza.IQ)
	if !ok {
		logPacketType(p)
		return
	}

	log.Printf("Iq: %#v\n", iq)
}

// HandleMessage processes an incoming XMPP message
func HandleMessage(s xmpp.Sender, p stanza.Packet) {
	msg, ok := p.(stanza.Message)
	if !ok {
		logPacketType(p)
		return
	}

	component, ok := s.(*xmpp.Component)
	if !ok {
		log.Error("Not a component")
		return
	}

	if msg.Type != "error" && msg.Body != "" {
		log.WithFields(log.Fields{
			"from": msg.From,
			"to":   msg.To,
		}).Warn("Message")
		log.Debugf("%#v", msg)

		fromJid, err := xmpp.NewJid(msg.From)
		if err != nil {
			log.Error("Invalid from JID!")
			return
		}

		session, ok := sessions[fromJid.Bare()]
		if !ok {
			log.Error("Message from stranger")
			return
		}

		toParts := strings.Split(msg.To, "@")
		toID := toParts[0]
		if len(toParts) > 1 {
			toIDInt, err := strconv.Atoi(toID)
			if err != nil {
				session.ProcessOutgoingMessage(toIDInt, msg.Body, 0)
				return
			}
		} else if toID == gateway.Jid.Bare() {
			bodyFields := strings.Fields(msg.Body)
			cmd := bodyFields[0]
			if strings.HasPrefix(cmd, "/") {
				response := session.ProcessTransportCommand(cmd[1:], bodyFields[1:])
				if response != "" {
					gateway.SendMessage(msg.From, "", response, component)
				}
				return
			}
		}
		log.Warn("Unknown purpose of the message, skipping")
	}
}

// HandlePresence processes an incoming XMPP presence
func HandlePresence(s xmpp.Sender, p stanza.Packet) {
	prs, ok := p.(stanza.Presence)
	if !ok {
		logPacketType(p)
		return
	}

	if prs.Type == "subscribe" {
		handleSubscription(s, prs)
	}
	if prs.To == gateway.Jid.Bare() {
		handlePresence(s, prs)
	}
}

func handleSubscription(s xmpp.Sender, p stanza.Presence) {
	log.WithFields(log.Fields{
		"from": p.From,
		"to":   p.To,
	}).Warn("Subscription request")
	log.Debugf("%#v", p)

	reply := stanza.Presence{Attrs: stanza.Attrs{
		From: p.To,
		To:   p.From,
		Id:   p.Id,
		Type: "subscribed",
	}}

	_ = s.Send(reply)
}

func handlePresence(s xmpp.Sender, p stanza.Presence) {
	presenceType := p.Type
	if presenceType == "" {
		presenceType = "online"
	}

	component, ok := s.(*xmpp.Component)
	if !ok {
		log.Error("Not a component")
		return
	}

	log.WithFields(log.Fields{
		"type": presenceType,
		"from": p.From,
		"to":   p.To,
	}).Warn("Presence")
	log.Debugf("%#v", p)

	fromJid, err := xmpp.NewJid(p.From)
	if err != nil {
		log.Error("Invalid from JID!")
		return
	}
	bareFromJid := fromJid.Bare()
	session, ok := getTelegramInstance(bareFromJid, &persistence.Session{}, component)
	if !ok {
		return
	}

	switch p.Type {
	case "unsubscribed", "unsubscribe":
		session.Disconnect()
		delete(sessions, bareFromJid)
	case "unavailable", "error":
		session.Disconnect()
	case "", "online":
		// due to the weird implentation of go-tdlib wrapper, it won't
		// return the client instance until successful authorization
		go func() {
			err = session.Connect()
			if err != nil {
				log.Error(errors.Wrap(err, "TDlib connection failure"))
			}
		}()
	}
}