from quotes.models import QuoteTag
from django.db.models import Count, Max

def build_cloud():
    maxtag = QuoteTag.objects \
                     .all() \
                     .aggregate(max=Max('quote'))['max']
    print maxtag
    tags = QuoteTag.objects \
                   .annotate(num_quotes=Count('quote'),
                             size=Count(1)) \
                   .order_by('-num_quotes')[:20]

    for tag in tags:
        tag.size = int(10 * float(tag.num_quotes) / maxtag)
    
    return {'cloud': tags}