#!/usr/bin/env python
#
# Credits: http://code.activestate.com/recipes/358449-wake-on-lan/

import socket
import struct
import sys

def wake_on_lan(macaddress):
    """ Switches on remote computers using WOL. """

    # Check macaddress format and try to compensate.
    if len(macaddress) == 12:
        pass
    elif len(macaddress) == 12 + 5:
        sep = macaddress[2]
        macaddress = macaddress.replace(sep, '')
    else:
        raise ValueError('Incorrect MAC address format')
 
    # Pad the synchronization stream.
    data = ''.join(['FFFFFFFFFFFF', macaddress * 20])
    send_data = '' 

    # Split up the hex values and pack.
    for i in range(0, len(data), 2):
        send_data = ''.join([send_data,
                             struct.pack('B', int(data[i: i + 2], 16))])

    # Broadcast it to the LAN.
    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
    sock.sendto(send_data, ('<broadcast>', 7))
    

if __name__ == '__main__':
    hostmac = { 'brahm' : '00:13:d3:a7:24:51' }
    if len(sys.argv) == 1:
       print "Usage: %s <macaddr|host>" % sys.argv[0]
       print ""
       print "Hosts configured: "
       for host, mac in hostmac.iteritems():
          print "  - %s : %s" % (host, mac)
       sys.exit(64)

    if hostmac.has_key(sys.argv[1]):
       wake_on_lan(hostmac[sys.argv[1]])
    else:
       wake_on_lan(sys.argv[1])