import calendar
from itertools import chain

from django.conf import settings
from django.core.mail import EmailMultiAlternatives
from django.template.loader import render_to_string

from store_order.models import OrderItem, Order


def year_list(current_year, num_years=5):
    """ Return a list of years, starting at current year ending with
    (current year + num_years), the default is 5
    """
    return [(i, i) for i in range(current_year, current_year + num_years)]


def month_list():
    """ Return iterated list of months
    """
    return [(i, calendar.month_name[i]) for i in
            range(1, len(calendar.month_name))]


def get_renewals_by_user(user):
    """ Returns subscriptions (OrderItems) by user

        Each subscription
    """
    from accounts.subscriptions import Subscription

    if not user:
        return None

    ordered_items = get_subscriptions().filter(
        order__user=user, gift_detail__exact=None)
    order_items = list(chain(ordered_items))

    subscriptions = []
    for order_item in order_items:
        if order_item.product.child().renewal:
            subscriptions.append(Subscription(
                order_item.product.title,
                order_item.order.date,
                order_item.product.child().duration))

    return subscriptions


def get_subscriptions_by_user(user):
    """ Returns subscriptions (OrderItems) by user

        Each subscription
    """
    from accounts.subscriptions import Subscription

    if not user:
        return None

    ordered_items = get_subscriptions().filter(
        order__user=user, gift_detail__exact=None)

    gifted_items = get_subscriptions().filter(
        gift_detail__email__iexact=user.email)

    order_items = list(chain(ordered_items, gifted_items))

    subscriptions = []
    for order_item in order_items:
        if not order_item.product.child().renewal:
            subscriptions.append(Subscription(
                order_item.product.title,
                order_item.order.date,
                order_item.product.child().duration))

    return subscriptions


def get_subscriptions(order=None):
    """ Subscriptions are really OrderItems with a subscription product
    attached.
    """
    from catalog.models import Subscription
    order_items = OrderItem.objects.filter(
        product__subclass_type__iexact=Subscription.__name__.lower())

    if order:
        order_items = order_items.filter(order=order)

    return order_items


def send_change_of_address_email(
        title, account_number, date_effective, date_from, date_to,
        old_address, new_address):

    template = 'storefront/change_of_address_email.html'
    DEFAULT_FROM_EMAIL = getattr(settings, 'DEFAULT_FROM_EMAIL')
    NOTIFICATIONS_EMAIL = getattr(settings, 'NOTIFICATIONS_EMAIL', [])
    subject, from_email, to = ('Change of Address Update', DEFAULT_FROM_EMAIL,
                               NOTIFICATIONS_EMAIL)

    data = {'old_address': old_address, 'new_address': new_address}
    data.update({'title': title, 'account_number': account_number})
    data.update({'date_effective': date_effective, 'date_from': date_from,
                 'date_to': date_to})

    text_content = render_to_string(template, dictionary=data)
    html_content = render_to_string(template, dictionary=data)

    msg = EmailMultiAlternatives(subject, text_content, from_email, to)
    msg.attach_alternative(html_content, "text/html")
    msg.send()


def send_new_account_email(email, password, user, profile, site):

    template = 'storefront/new_account_email.html'
    DEFAULT_FROM_EMAIL = getattr(settings, 'DEFAULT_FROM_EMAIL')
    subject, from_email, to = ('New Account', DEFAULT_FROM_EMAIL, email)

    data = {'email': email, 'password': password, 'site': site}
    data.update({'first_name': user.first_name, 'last_name': user.last_name})
    data.update({'company': profile.company, 'address1': profile.address1,
                 'address2': profile.address2, 'city': profile.city,
                 'region': profile.region, 'phone': profile.phone,
                 'country': profile.country})

    text_content = render_to_string(template, dictionary=data)
    html_content = render_to_string(template, dictionary=data)

    msg = EmailMultiAlternatives(subject, text_content, from_email, [to])
    msg.attach_alternative(html_content, "text/html")
    msg.send()