viewutil.py

import re
import operator
from decimal import Decimal

from django.db.models import Count, Sum, Max, Avg, Q, Func
from django.core.urlresolvers import reverse
from django.db.models.functions import Coalesce
from django.http import Http404
from django.contrib.auth import get_user_model
from django.db import transaction
from django.conf import settings

from .models import *
from . import filters


def get_default_email_host_user():
    return getattr(settings, 'EMAIL_HOST_USER', '')


def get_default_email_from_user():
    return getattr(settings, 'EMAIL_FROM_USER', get_default_email_host_user())


def admin_url(obj):
    return reverse("admin:%s_%s_change" % (obj._meta.app_label, obj._meta.object_name.lower()), args=(obj.pk,), current_app=obj._meta.app_label)

# Adapted from http://djangosnippets.org/snippets/1474/
# TODO: use request.build_absolute_uri instead

def get_request_server_url(request):
    if request:
        return request.build_absolute_uri('/')
    else:
        raise Exception("Request was null.")


def get_referer_site(request):
    origin = request.META.get('HTTP_ORIGIN', None)
    if origin != None:
        return re.sub(r'^https?:\/\/', '', origin)
    else:
        return None


def get_event(event):
    if event:
        if isinstance(event, Event):
            return event
        try:
            if re.match(r'^\d+$', event):
                return Event.objects.get(id=event)
            else:
                return Event.objects.get(short=event)
        except Event.DoesNotExist:
            raise Http404
    e = Event()
    e.id = None
    e.name = 'All Events'
    return e


def request_params(request):
    if request.method == 'GET':
        return request.GET
    elif request.method == 'POST':
        return request.POST
    else:
        raise Exception(
            "No request parameters associated with this request method.")


_1ToManyBidsAggregateFilter = Q(bids__donation__transactionstate='COMPLETED')
_1ToManyDonationAggregateFilter = Q(donation__transactionstate='COMPLETED')
DonationBidAggregateFilter = _1ToManyDonationAggregateFilter
DonorAggregateFilter = _1ToManyDonationAggregateFilter
EventAggregateFilter = _1ToManyDonationAggregateFilter
PrizeWinnersFilter = Q(prizewinner__acceptcount_gt=0) | Q(
    prizewinner__pendingcount__gt=0)

# http://stackoverflow.com/questions/5722767/django-mptt-get-descendants-for-a-list-of-nodes


def get_tree_queryset_descendants(model, nodes, include_self=False):
    if not nodes:
        return nodes
    filters = []
    for n in nodes:
        lft, rght = n.lft, n.rght
        if include_self:
            lft -= 1
            rght += 1
        filters.append(Q(tree_id=n.tree_id, lft__gt=lft, rght__lt=rght))
    q = reduce(operator.or_, filters)
    return model.objects.filter(q).order_by(*model._meta.ordering)

# http://stackoverflow.com/questions/6471354/efficient-function-to-retrieve-a-queryset-of-ancestors-of-an-mptt-queryset


def get_tree_queryset_ancestors(model, nodes):
    tree_list = {}
    query = Q()
    for node in nodes:
        if node.tree_id not in tree_list:
            tree_list[node.tree_id] = []
        parent = node.parent.pk if node.parent is not None else None,
        if parent not in tree_list[node.tree_id]:
            tree_list[node.tree_id].append(parent)
            query |= Q(lft__lt=node.lft, rght__gt=node.rght,
                       tree_id=node.tree_id)
        return model.objects.filter(query).order_by(*model._meta.ordering)


def get_tree_queryset_all(model, nodes):
    filters = []
    for node in nodes:
        filters.append(Q(tree_id=node.tree_id))
    q = reduce(operator.or_, filters)
    return model.objects.filter(q).order_by(*model._meta.ordering)


ModelAnnotations = {
    'event': {
        'amount': Coalesce(Sum('donation__amount', only=EventAggregateFilter), Decimal('0.00')),
        'count': Count('donation', only=EventAggregateFilter),
        'max': Coalesce(Max('donation__amount', only=EventAggregateFilter), Decimal('0.00')),
        'avg': Coalesce(Avg('donation__amount', only=EventAggregateFilter), Decimal('0.00')),
    },
    'prize': {'numwinners': Count('prizewinner', only=PrizeWinnersFilter), },
}


def find_people(people_list):
    result = []
    for person in people_list:
        try:
            d = Donor.objects.get(alias__iequals=person)
            result.append(d)
        except:
            pass
    return result


def prizecmp(a, b):
    # if both prizes are run-linked, sort them that way
    if a.startrun and b.startrun:
        return cmp(a.startrun.starttime, b.startrun.starttime) or cmp(a.endrun.endtime, b.endrun.endtime) or cmp(a.name, b.name)
    # else if they're both time-linked, sort them that way
    if a.starttime and b.starttime:
        return cmp(a.starttime, b.starttime) or cmp(a.endtime, b.endtime) or cmp(a.name, b.name)
    # run-linked prizes are listed after time-linked and non-linked
    if a.startrun and not b.startrun:
        return 1
    if b.startrun and not a.startrun:
        return -1
    # time-linked prizes are listed after non-linked
    if a.starttime and not b.starttime:
        return 1
    if b.starttime and not a.starttime:
        return -1
    # sort by category or name as a fallback
    return cmp(a.category, b.category) or cmp(a.name, b.name)


EVENT_SELECT = 'admin-event'


def get_selected_event(request):
    evId = request.session.get(EVENT_SELECT, None)
    if evId:
        return Event.objects.get(pk=evId)
    else:
        return None


def set_selected_event(request, event):
    if event:
        request.session[EVENT_SELECT] = event.id
    else:
        request.session[EVENT_SELECT] = None


def get_donation_prize_contribution(prize, donation, secondaryAmount=None):
    if prize.contains_draw_time(donation.timereceived):
        amount = secondaryAmount if secondaryAmount != None else donation.amount
        if prize.sumdonations or amount >= prize.minimumbid:
            return amount
    return None


def get_donation_prize_info(donation):
    """ Attempts to find a list of all prizes this donation gives the donor eligibility for.
      Does _not_ attempt to relate this information to any _past_ eligibility.
      Returns the set as a list of {'prize','amount'} dictionaries. """
    prizeList = []
    for ticket in donation.tickets.all():
        contribAmount = get_donation_prize_contribution(
            ticket.prize, donation, ticket.amount)
        if contribAmount != None:
            prizeList.append({'prize': ticket.prize, 'amount': contribAmount})
    for timeprize in filters.run_model_query('prize', params={'feed': 'current', 'ticketdraw': False, 'offset': donation.timereceived, 'noslice': True}):
        contribAmount = get_donation_prize_contribution(timeprize, donation)
        if contribAmount != None:
            prizeList.append({'prize': timeprize, 'amount': contribAmount})
    return prizeList


def tracker_log(category, message='', event=None, user=None):
    Log.objects.create(category=category, message=message,
                       event=event, user=user)


def merge_bids(rootBid, bids):
    for bid in bids:
        if bid != rootBid:
            for donationBid in bid.bids.all():
                donationBid.bid = rootBid
                donationBid.save()
            for suggestion in bid.suggestions.all():
                suggestion.bid = rootBid
                suggestion.save()
            bid.delete()
    rootBid.save()
    return rootBid


def merge_donors(rootDonor, donors):
    for other in donors:
        if other != rootDonor:
            for donation in other.donation_set.all():
                donation.donor = rootDonor
                donation.save()
            for prizewin in other.prizewinner_set.all():
                prizewin.winner = rootDonor
                prizewin.save()
            other.delete()
    rootDonor.save()
    return rootDonor


def autocreate_donor_user(donor):
    AuthUser = get_user_model()

    if not donor.user:
        with transaction.atomic():
            try:
                linkUser = AuthUser.objects.get(email=donor.email)
            except AuthUser.MultipleObjectsReturned:
                message = 'Multiple users found for email {0}, when trying to mail donor {1} for prizes'.format(
                    donor.email, donor.id)
                tracker_log('prize', message)
                raise Exception(message)
            except AuthUser.DoesNotExist:
                targetUsername = donor.email
                if donor.alias and not AuthUser.objects.filter(username=donor.alias):
                    targetUsername = donor.alias
                linkUser = AuthUser.objects.create(
                    username=targetUsername, email=donor.email, first_name=donor.firstname, last_name=donor.lastname, is_active=False)
            donor.user = linkUser
            donor.save()

    return donor.user