# -*- Mode: Python -*-

# monitor client, unix version.

import asyncore
import asynchat
import socket
import string
import sys
import os

import md5

class stdin_channel (asyncore.file_dispatcher):
    def handle_read (self):
        data = self.recv(512)
        if not data:
            print '\nclosed.'
            self.sock_channel.close()
            try:
                self.close()
            except:
                pass

        data = string.replace(data, '\n', '\r\n')
        self.sock_channel.push (data)

    def writable (self):
        return 0

    def log (self, *ignore):
        pass

class monitor_client (asynchat.async_chat):
    def __init__ (self, password, addr=('',8023), socket_type=socket.AF_INET):
        asynchat.async_chat.__init__ (self)
        self.create_socket (socket_type, socket.SOCK_STREAM)
        self.terminator = '\r\n'
        self.connect (addr)
        self.sent_auth = 0
        self.timestamp = ''
        self.password = password

    def collect_incoming_data (self, data):
        if not self.sent_auth:
            self.timestamp = self.timestamp + data
        else:
            sys.stdout.write (data)
            sys.stdout.flush()

    def found_terminator (self):
        if not self.sent_auth:
            self.push (hex_digest (self.timestamp + self.password) + '\r\n')
            self.sent_auth = 1
        else:
            print

    def handle_close (self):
        # close all the channels, which will make the standard main
        # loop exit.
        map (lambda x: x.close(), asyncore.socket_map.values())

    def log (self, *ignore):
        pass

class encrypted_monitor_client (monitor_client):
    "Wrap push() and recv() with a stream cipher"

    def init_cipher (self, cipher, key):
        self.outgoing = cipher.new (key)
        self.incoming = cipher.new (key)

    def push (self, data):
        # push the encrypted data instead
        return monitor_client.push (self, self.outgoing.encrypt (data))

    def recv (self, block_size):
        data = monitor_client.recv (self, block_size)
        if data:
            return self.incoming.decrypt (data)
        else:
            return data

def hex_digest (s):
    m = md5.md5()
    m.update (s)
    return string.join (
            map (lambda x: hex (ord (x))[2:], map (None, m.digest())),
            '',
            )

if __name__ == '__main__':
    if len(sys.argv) == 1:
        print 'Usage: %s host port' % sys.argv[0]
        sys.exit(0)

    if ('-e' in sys.argv):
        encrypt = 1
        sys.argv.remove ('-e')
    else:
        encrypt = 0

    sys.stderr.write ('Enter Password: ')
    sys.stderr.flush()
    try:
        os.system ('stty -echo')
        p = raw_input()
        print
    finally:
        os.system ('stty echo')
    stdin = stdin_channel (0)
    if len(sys.argv) > 1:
        if encrypt:
            client = encrypted_monitor_client (p, (sys.argv[1], string.atoi (sys.argv[2])))
            import sapphire
            client.init_cipher (sapphire, p)
        else:
            client = monitor_client (p, (sys.argv[1], string.atoi (sys.argv[2])))
    else:
        # default to local host, 'standard' port
        client = monitor_client (p)
    stdin.sock_channel = client
    asyncore.loop()
