#!/usr/bin/python

import csv
import email.parser
from optparse import OptionParser
import os
import smtplib
import subprocess
import sys


sender_header = 'mail-merge-sender@mit.edu'
rtkit_path = '/afs/athena.mit.edu/user/a/d/adehnert/arch/common/lib/python/'
smtp = None

def dictize_line(header, line,):
    line_dict = {}
    for key, elem in zip(header, line, ):
        line_dict[key]=elem
    return line_dict

def setup_sendmail_smtp():
    global smtp
    smtp = smtplib.SMTP()
    smtp.connect()
def sendmail_smtp(addrs, text):
    global smtp
    smtp.sendmail(sender_header, addrs, text, )
smtp_funcs = (setup_sendmail_smtp, sendmail_smtp, )

def sendmail_cmd(addrs, text):
    args = ["/usr/lib/sendmail", "--", ]
    args.extend(addrs)
    proc = subprocess.Popen(args, stdin=subprocess.PIPE)
    proc.communicate(text)
    if proc.returncode != 0:
        raise RuntimeError, "sendmail returned %d" % (proc.returncode, )
cmd_funcs = (lambda: True, sendmail_cmd)

setup_sendmail, sendmail = smtp_funcs
setup_sendmail, sendmail = cmd_funcs

def parse_arguments():
    parser = OptionParser(usage='usage: %prog [options] cc_addr template recipients')
    parser.add_option('-q', '--rt-queue', dest='rt_queue',
            help='Automatically create a ticket in queue QUEUE',
            metavar='QUEUE',
    )
    parser.add_option('-o', '--rt-owner', dest='rt_owner',
            help='Set RT owner and AdminCC to USER',
            metavar='USER',
    )
    parser.add_option('--split', dest='split',
            help='Split "email" field on SPLIT and send to each recipient',
            metavar='SPLIT',
    )
    (options, args) = parser.parse_args()
    if len(args) != 3:
        parser.error("incorrect number of arguments")
    if options.rt_owner and not options.rt_queue:
        parser.error("--rt-owner requires specifying a queue")
    return options, args

def nop_msg_filter(rcpts, body):
    return rcpts, body

def msg_filter_factory(opts):
    if not opts.rt_queue:
        return nop_msg_filter

    try:
        import rtkit.tracker, rtkit.authenticators, rtkit.errors
    except ImportError:
        print "Note: using rtkit from %s" % (rtkit_path, )
        sys.path.append(rtkit_path)
        import rtkit.tracker, rtkit.authenticators, rtkit.errors

    cookie = rtkit.authenticators.CookieAuthenticator
    resource = rtkit.resource.RTResource.from_rtrc(cookie)
    parser = email.parser.Parser()

    def filter_rt(rcpts, body, ):
        msg = parser.parsestr(body)
        content = {
            'content': {
                'Requestors': ", ".join(rcpts),
                'Queue': opts.rt_queue,
                'Subject' : msg['Subject'],
                'Text' : '',
            }
        }
        if opts.rt_owner:
            content['content']['AdminCC'] = opts.rt_owner
            content['content']['Owner'] = opts.rt_owner

        try:
            response = resource.post(path='ticket/new', payload=content,)
            results = dict(response.parsed[0])
            ticket, ticket_number = results['id'].split('/')
            assert ticket == 'ticket', 'unexpected value "%s" instead of ticket' % (ticket, )
            subject = "%s [help.mit.edu #%s]" % (msg['Subject'], ticket_number)
            del msg['Subject']
            msg['Subject'] = subject
        except rtkit.errors.RTResourceError as e:
            logger.error(e.response.status_int)
            logger.error(e.response.status)
            logger.error(e.response.parsed)

        # We don't want to send mail to the real recipient, because RT
        # will send them a copy too.
        return [], msg.as_string()

    return filter_rt

def mail_merge(opts, cc_addr, email_file, recipients_file):
    email_tmpl = open(email_file, 'rU').read()
    reader = csv.reader(open(recipients_file, 'rU'))
    header = reader.next()
    msg_filter = msg_filter_factory(opts)
    print header
    if not 'email' in header:
        print >>sys.stderr, "Your CSV file doesn't have an email field. You should fix that.\n(Note that this script is case-sensitive.)"
        return False
    for line in reader:
        dct = dictize_line(header, line, )
        print dct
        text = email_tmpl % dct
        if opts.split:
            prop_rcpts = dct['email'].split(opts.split)
        else:
            prop_rcpts = [dct['email']]
        rcpts, text = msg_filter(prop_rcpts, text, )
        rcpts.append(cc_addr)
        sendmail(rcpts, text, )

if __name__=='__main__':
    options, args = parse_arguments()
    setup_sendmail()
    mail_merge(options, *args)