#!/usr/bin/env python

# hardcoded username and password - un-comment these to enable

#myUsername = "something"
#myPassword = "reallysecret"

"""
jsusage

A utility for doing the boring interaction with the
Telecom Jetstream website, passing in your
username and password, and retrieving your usage
for the current month

You can run this as a shell script with the arguments:
    - username
    - password

Alternatively, you can hard-code the username and password
by editing and uncommenting the declarations above.

Alternatively again, you can put your username and password
(separated by a newline or space) into the file
.jetstreamrc in your home directory.

Save this file, put it into your execution path, and
chmod it executable (I recommend mode 700).

(Or alternatively again, you can rename this file to
jsusage.py, and import the JSUsage class into your
own Python programs).
"""

import sys, os, re
from urllib import urlencode
from urllib2 import Request, HTTPSHandler, urlopen, build_opener, install_opener

# URL from which we're retrieving usage info
reportUrl = "https://jetstream-usage.telecom.co.nz/cgi-bin/iaf/iafReports"

# file into which this util will try to read your jetstream username/passwd
jspath = os.path.expanduser("~/.jetstreamrc")

reSpaces = re.compile("\\s+")
class JSUsageFetcher:
    """
    Class for mining one's jetstream usage info from Telecom website
    
    this class interacts with the Telecom website, pretending
    to be a web browser, logs in, and clicks through to the
    page containing one's usage info.
    
    Once this page is retrieved, we mine it for the current
    usage figure.
    """
    def __init__(self, *args, **kw):
        self.verbose = kw.get('verbose', 0)
    def getusage(self, username, password):
        """
        Retrieve the Telecom Jetstream usage for a
        given username/password
    
        Arguments:
            - username
            - password
        
        Return:
            - current month's usage in megabytes (float)
        """
        # set up for HTTPS access
        o = build_opener(HTTPSHandler)
        install_opener(o)
    
        # build a Request object
        req = self.req = Request(reportUrl)
    
        # whack in the form fields
        form = {"formEvent": "generate",
                "formName": "cscUserUsageBasic.html",
                "IAF_type": "csc_usage.sh",
                "IAF_usePrinter": "S",
                "IAF_printerName": "",
                "IAF_startAccount": "0",
                "IAF_endAccount": "0",
                "IAF_rangeType": "O",
                "domain": "null",
                "IAF_SERVER_SERVICE": "iafserver",
                "IAF_SERVER": "se259",
                "HGE_LOCALE": "hgeTemplates/csc/",
                "IAF_LogonType": "USER",
                "IAF_customerNumber": "",
                "IAF_userID": username,
                "IAF_LogonUserID": username,
                "IAF_LogonPassword": password,
                }
        req.add_data(urlencode(form.items()))
    
        # hit the Telecom https server
        if self.verbose:
            print "opening %s" % reportUrl
        u = self.u = urlopen(req)
    
        # get the full raw response
        raw = self.raw = u.read()
    
        # lop off the bit we're interested in
        raw1 = self.raw1 = raw.split("<TR><TD COLSPAN=3 ALIGN=RIGHT>Total:</TD><TD ALIGN=RIGHT NOWRAP>", 1)[1].strip()
    
        # and just get the current month total usage
        usage = reSpaces.split(raw1, 1)[0]
    
        # got it
        if self.verbose:
            print "usage = %s" % usage
        return float(usage)

def getusage(username, password):
    """
    Creates a JSUsage class and runs it
    
    Arguments:
        - username
        - password
    
    Return:
        - current month's usage in megabytes (float)
    """
    return JSUsageFetcher().getusage(username, password)


def help():
    
    print "usage: %s username password" % sys.argv[0]
    print "retrieves current usage stat from Telecom Jetstream website"
    print "You can store your username and password, separated by a newline,"
    print "in the file '%s' instead" % jspath
    sys.exit(1)

def main():
    # any args on command line?
    if len(sys.argv) == 3:
        username, password = sys.argv[1:]
    else:
        # see if user has hard-coded these
        try:
            username, password = myUsername, myPassword
        except:
            # no - try the user file
            if os.path.isfile(jspath):
                username, password = reSpaces.split(open(jspath).read().strip())[:2]
            else:
                # spit dummy
                help()

    # ok - do the business
    print getusage(username, password)
if __name__ == '__main__':
    main()