import socket, select


def broadcast_data(sock, message):
    for socket in CONNECTION_LIST:
        if socket != server_socket and socket != sock:
            try:
                socket.send(message)
            except:
                # broken socket connection may be, chat client pressed ctrl+c for example
                socket.close()
                CONNECTION_LIST.remove(socket)


def send_data_directly(sender_name, sendee_name, message):
    print(sendee_name)
    for socket, username in USERNAMES.items():
        if username == sendee_name:
            if socket != server_socket:
                socket.send('<PRIVATE from ' + sender_name + '> ' + message)


if __name__ == "__main__":

    # List to keep track of socket descriptors
    CONNECTION_LIST = []
    USERNAMES = {}
    RECV_BUFFER = 4096
    PORT = 5000

    server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    server_socket.bind(("0.0.0.0", PORT))
    server_socket.listen(10)

    # Add server socket to the list of readable connections
    CONNECTION_LIST.append(server_socket)

    print "Chat server started on port " + str(PORT)

    while 1:
        # Get the list sockets which are ready to be read through select
        read_sockets,write_sockets,error_sockets = select.select(CONNECTION_LIST,[],[])

        for sock in read_sockets:
            #New connection
            if sock == server_socket:
                sockfd, addr = server_socket.accept()
                CONNECTION_LIST.append(sockfd)
                print "Client (%s, %s) connected" % addr


            #Some incoming message from a client
            else:
                try:
                    data = sock.recv(RECV_BUFFER)
                    if data:
                        if data[0] == '#':
                            USERNAMES[sock] = data[1:-1]
                            broadcast_data(server_socket, "Greetings to " + USERNAMES[sock] + "\n")
                        elif data[0] == '@':
                            send_data_directly(USERNAMES[sock], data.split(' ')[0][1:], data.split(' ', 1)[1])
                        else:
                            broadcast_data(sock, "\r" + '<' + USERNAMES[sock] + '>  ' + data)
                except:
                    broadcast_data(sock, "Farewell to " + USERNAMES[sock] + "\n")
                    print "Client (%s, %s) is offline" % addr
                    sock.close()
                    CONNECTION_LIST.remove(sock)
                    continue

    server_socket.close()