distributed chat client made for a golang hack night, it can both send and receive messages

chat-client.go

package main

import (
  "fmt"
  "flag"
  "net"
  "bufio"
  "os"
  "time"
  "strconv"
  "strings"
)

var connection_list []net.Conn
var seen = map[string]bool{}

func handlePeer(conn net.Conn, send chan string){
  println("Peer connected")

  connection_list = append(connection_list, conn)
  defer func(){
    //TODO remove from connections
    conn.Close()
  }()

  for {
    line, err := bufio.NewReader(conn).ReadString('\n')
    if err != nil {
      println("disconnecting peer")
      return
    }
    send <- line
  }
}

func handleBroadcast(send chan string) {
  for s := range send {
    bits := strings.SplitN(s, " ", 3)
    if len(bits) != 3 {
      fmt.Printf("Error: invalid line: %v\n", bits)
      continue
    }
    if seen[bits[0]] {
      continue
    }
    fmt.Printf("%s: %s", bits[1], bits[2])
    seen[bits[0]] = true
    for _, conn := range connection_list {
      _, err := conn.Write([]byte(s + "\n"))
      if err != nil {
        fmt.Printf("error writing out to connection: %s \n", err)
      }
    }
  }
}

func listen(listen_host string, send chan string) {
  fmt.Printf("listening on %s \n", listen_host)
  listen, _ := net.Listen("tcp", listen_host)
  go handleBroadcast(send)
  for {
    conn, err := listen.Accept()
    if err != nil {
      continue
    }
    go handlePeer(conn, send)
  }
}

func main() {
  var peer, host, ident string

  flag.StringVar(&host, "h", "localhost:4569", "Your localhost that you are listening on")
  flag.StringVar(&peer, "p", "", "A peer to initially connect to")
  flag.StringVar(&ident, "i", "anon", "identity on the chat")
  flag.Parse()

  send := make(chan string)
  if peer != "" {
    fmt.Printf("connecting to %s \n", peer)
    say, _ := net.Dial("tcp", peer)
    go handlePeer(say, send)
  }
  go listen(host, send)

  scanner := bufio.NewScanner(os.Stdin)
  for scanner.Scan() {
    send <- strconv.FormatInt(time.Now().Unix(), 10) + " " + ident + " " + scanner.Text() + "\n"
  }
}