// The lowest level of XMPP protocol, where TLS is applied after the

// initial handshake.

package xmpp

import (

	"crypto/tls"

	"io"

	"net"

	"time"

)

var l1interval = time.Second

type layer1 struct {

	sock      net.Conn

	recvSocks chan<- net.Conn

	sendSocks chan net.Conn

}

func startLayer1(sock net.Conn, recvWriter io.WriteCloser,

	sendReader io.ReadCloser, status <-chan Status) *layer1 {

	l1 := layer1{sock: sock}

	recvSocks := make(chan net.Conn)

	l1.recvSocks = recvSocks

	sendSocks := make(chan net.Conn, 1)

	l1.sendSocks = sendSocks

	go recvTransport(recvSocks, recvWriter, status)

	go sendTransport(sendSocks, sendReader)

	recvSocks <- sock

	sendSocks <- sock

	return &l1

}

func (l1 *layer1) startTls(conf *tls.Config) {

	sendSockToSender := func(sock net.Conn) {

		for {

			select {

			case <-l1.sendSocks:

			case l1.sendSocks <- sock:

				return

			}

		}

	}

	sendSockToSender(nil)

	l1.recvSocks <- nil

	l1.sock = tls.Client(l1.sock, conf)

	sendSockToSender(l1.sock)

	l1.recvSocks <- l1.sock

}

func recvTransport(socks <-chan net.Conn, w io.WriteCloser,

	status <-chan Status) {

	defer w.Close()

	var sock net.Conn

	p := make([]byte, 1024)

	for {

		select {

		case stat := <-status:

			if stat == StatusShutdown {

				return

			}

		case sock = <-socks:

		default:

		}

		if sock == nil {

			time.Sleep(l1interval)

		} else {

			sock.SetReadDeadline(time.Now().Add(l1interval))

			nr, err := sock.Read(p)

			if nr == 0 {

				if errno, ok := err.(*net.OpError); ok {

					if errno.Timeout() {

						continue

					}

				}

				Warn.Logf("recvTransport: %s", err)

				return

			}

			nw, err := w.Write(p[:nr])

			if nw < nr {

				Warn.Logf("recvTransport: %s", err)

				return

			}

		}

	}

}

func sendTransport(socks <-chan net.Conn, r io.Reader) {

	var sock net.Conn

	p := make([]byte, 1024)

	for {

		nr, err := r.Read(p)

		if nr == 0 {

			Warn.Logf("sendTransport: %s", err)

			break

		}

		for nr > 0 {

			select {

			case sock = <-socks:

				if sock != nil {

					defer sock.Close()

				}

			default:

			}

			if sock == nil {

				time.Sleep(l1interval)

			} else {

				nw, err := sock.Write(p[:nr])

				nr -= nw

				if nr != 0 {

					Warn.Logf("write: %s", err)

					break

				}

			}

		}

	}

}