"""Common utilities for both the chatclient and chatserver programs.

Written by Tom Magrino
"""
MSG_SIZE_LIMIT = 4096


def decode_message(msg_text):
    """Create a message given the str representation of the message."""
    msg_parts = msg_text.split("|")
    src = msg_parts[0]
    dst = msg_parts[1]
    action = msg_parts[2]
    body = "|".join(msg_parts[3:])
    return Message(src, dst, action, body)


class Message(object):

    def __init__(self, src, dst, action, body):
        self.src = src
        self.dst = dst
        self.action = action
        self.body = body

    def __str__(self):
        """String representation of Message:

        >>> m = Message("1.1.1.1", "1.1.1.2", "hello", "")
        >>> str(m)
        '1.1.1.1|1.1.1.2|hello|'
        """
        return "{0}|{1}|{2}|{3}".format(self.src, self.dst, self.action,
                                        self.body)

    def __repr__(self):
        """Representation of Message for REPL:

        >>> m = Message("1.1.1.1", "1.1.1.2", "hello", "")
        >>> repr(m)
        'Message("1.1.1.1", "1.1.1.2", "hello", "")'
        """
        return 'Message("{0}", "{1}", "{2}", "{3}")'.format(self.src, self.dst,
                                                            self.action,
                                                            self.body)