package xmpp

import (
	"context"
	"crypto/tls"
	"crypto/x509"
	"encoding/xml"
	"io"
	"log"
)

type SessionConnect struct{}
type SessionDisconnect struct{}
type SessionShouldDisconnect struct{}

type session struct {
	jid         string
	pwd         string
	in          chan any
	out         chan<- any
	transport   *tls.Conn
	tx          *xml.Encoder
	rx          chan any
	resourceReq string
}

func StartSession(out chan<- any, jid string, pwd string) (in chan<- any) {
	s := session{}

	s.jid = jid
	s.pwd = pwd
	s.in = make(chan any)
	s.out = out
	s.rx = make(chan any, 0)

	go s.run()

	return s.in
}

func (s *session) run() {
	err := s.startTransport()
	if err != nil {
		return
	}
	defer s.transport.Close()

	ctx, cancel := context.WithCancel(context.Background())
	cpy := s.rx
	go runRx(ctx, cpy, s.transport)
	defer cancel()

	lw := logger{"[TX] "}
	w := io.MultiWriter(s.transport, lw)
	s.tx = xml.NewEncoder(w)
	defer s.tx.Close()

	openStream(s.tx, s.jid)
	defer closeStream(s.tx)

	s.out <- SessionConnect{} // TODO this should be sent after initial presence
	defer func() { s.out <- SessionDisconnect{} }()

	for {
		select {
		case e := <-s.rx:
			handle(s, e)
		case signal := <-s.in:
			switch signal.(type) {
			case SessionShouldDisconnect:
				return
			}
		}
	}
}

func (s *session) startTransport() error {
	domain := domainpart(s.jid)

	roots, err := x509.SystemCertPool()
	if err != nil {
		log.Println(err)
		return err
	}

	s.transport, err = tls.Dial("tcp", domain+":"+"5223", &tls.Config{RootCAs: roots})
	if err != nil {
		log.Println(err)
		return err
	}

	return nil
}