from django.core.mail import mail_managers
from django.core.urlresolvers import reverse

from .models import ResourceAllocation


def notify_allocation(request, new_alloc, old_alloc=None):
    fields = ['resource', 'service', 'route', 'start', 'end', 'active', 'notes']

    message = 'Bénévole : ' + str(request.user.profile)
    message += '\n\nAllocation :'

    diff = False
    for field in fields:
        new_attr = getattr(new_alloc, field)
        if new_attr == '' or new_attr is None:
            new_attr = '-'
        if old_alloc:
            old_attr = getattr(old_alloc, field)
            if old_attr == '' or old_attr is None:
                old_attr = '-'
        if old_alloc and old_attr != new_attr:
            message += '\n-%12s: %s\n+%12s: %s' % (field, old_attr, field, new_attr)
            diff = True
        else:
            message += '\n %12s: %s' % (field, new_attr)

    url = 'https' if request.is_secure() else 'http'
    url += '://' + request.get_host()
    url += reverse('admin:services_resourceallocation_change', args=(new_alloc.pk,))
    message += '\n\nVoir : ' + url

    if old_alloc and diff:
        sujet = 'Modification d’une allocation'
    elif not old_alloc:
        sujet = 'Nouvelle allocation'
    else:
        sujet = None

    if sujet:
        mail_managers(sujet, message)