#!/usr/bin/env python
# vim: tabstop=4 softtabstop=4 shiftwidth=4 textwidth=80 smarttab expandtab
"""
* Copyright (C) 2012  Sangoma Technologies Corp.
* All Rights Reserved.
*
* Author(s)
* Travis Semczyszyn <tsemczyszyn@sangoma.com>
*
* This is a simple script to scan for USB mass storage devices
* and find the serial number of a newly inserted device
*
"""

from os import listdir
from os import path
import sys
import signal
import re

def sig_handler(signal, frame):
    print "Exiting..."
    sys.exit(0)

signal.signal(signal.SIGINT, sig_handler)

print "#################################################################################"
print "Sangoma's USB Serial Scanner (you can press CTRL + C anytime to quit)"
print "#################################################################################\n"

if (path.exists('/proc/scsi/usb-storage')):
    list1 = listdir('/proc/scsi/usb-storage')

else:
    list1= []

while (1):

    sys.stdout.write("Please insert the USB key you want to use for the Sangoma license and press any key ...")
    sys.stdout.flush()
    sys.stdin.read(1)

    try:
        list2 = listdir('/proc/scsi/usb-storage')
    except OSError:
        print "No new USB key detected (failed to list /proc/scsi/usb-storage) ...\n"
        continue

    listdiff = set(list2) - set(list1)
    newlist = list(listdiff)

    if not newlist:
        print "No new USB key detected ...\n"
        continue

    serialPath = '/proc/scsi/usb-storage/' + newlist[0]
    try:
        procfile = open(serialPath, 'r')
    except OSError:
        print "No new USB key detected (Failed to open: %s) ...\n" % str(serialPath)
        continue

    matchtext = procfile.read()
    serialNumber = re.search("^Serial\s*Number:\s*(.+)?$", matchtext, re.MULTILINE)

    print "\n"
    print "###########################################"
    print "Your USB Serial number is " + serialNumber.group(1)
    print "###########################################"

    break