# -*- coding: utf-8 -*-

import datetime
import dateutil.parser
import dingguo
import email
import email.utils
import ioex
import pytz
import re

class UtcOffsetTimezone(datetime.tzinfo):

    def __init__(self, seconds):
        assert type(seconds) is int
        self.seconds = seconds

    def utcoffset(self, dt):
        return datetime.timedelta(seconds = self.seconds)

    def dst(self, dt):
        return None

    def tzname(self, dt):
        return self.__class__.__name__ + '(seconds = %d)' % self.seconds

def parse_order_confirmation_mail(mail):

    assert isinstance(mail, email.message.Message)

    msg_text = mail.get_payload(decode = True).decode('utf8')
    if not 'Wiener Linien' in msg_text:
        raise Exception()

    order_match = re.search(
        r'(?P<name>.*Ticket.*)\s+'
            + r'Valid from: (?P<valid_from>\d{1,2} \w+ \d{4} \d{1,2}:\d{2})\s+'
            + r'(Valid until: (?P<valid_until>\d{1,2} \w+ \d{4} \d{1,2}:\d{2})\s+)?'
            + r'Type: (?P<type>.* ticket)\s+'
            + r'For\:\s+'
            + r'(?P<passenger_first_name>Fabian Peter)\s+'
            + r'(?P<passenger_last_name>Hammerle)\s+'
            + ur'Price: (?P<currency>€)(?P<price>\d+.\d{2})\s+'
            + r'Quantity: (?P<quantity>1)\s+'
            ,
        msg_text,
        re.MULTILINE | re.UNICODE
        )
    if not order_match:
        print(repr(msg_text))
    order_match_groups = order_match.groupdict()

    email_recipient_address = mail['delivered-to'].decode('utf8')
    email_date = dateutil.parser.parse(mail['date'])
    order = dingguo.Order(
        platform = u'wiener_linien',
        order_id = '%s-%sZ' % (
            email_recipient_address,
            email_date.astimezone(pytz.utc).replace(tzinfo = None).isoformat(),
            ),
        order_date = email_date,
        customer_id = email_recipient_address,
        )

    assert int(order_match_groups['quantity']) == 1

    ticket_url_match = re.search(
        ur'following link:\s+(http[^\s]+)',
        msg_text,
        re.MULTILINE | re.UNICODE,
        )

    with ioex.setlocale('en_US.UTF-8'):
        timezone = UtcOffsetTimezone(email.utils.parsedate_tz(mail['date'])[9])
        order.items.append(dingguo.Transportation(
            name = order_match_groups['name'],
            price_brutto = dingguo.Sum(
                float(order_match_groups['price']),
                order_match_groups['currency'],
                ),
            passenger = dingguo.Person(
                first_name = order_match_groups['passenger_first_name'],
                last_name = order_match_groups['passenger_last_name'],
                ),
            valid_from = datetime.datetime.strptime(order_match_groups['valid_from'], '%d %B %Y %H:%M')
                .replace(tzinfo = timezone),
            valid_until = datetime.datetime.strptime(order_match_groups['valid_until'], '%d %B %Y %H:%M')
                .replace(tzinfo = timezone) if order_match_groups['valid_until'] else None,
            ticket_url = ticket_url_match.group(1) if ticket_url_match else None,
            ))

    return [order]