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import calendar
#from calendar import HTMLCalendar
from datetime import date
from itertools import groupby

from django.utils.html import conditional_escape as esc
from django.utils.translation import ugettext_lazy as _
from django.utils.translation import get_language
#from django.db import models

class EventCalendar(calendar.LocaleHTMLCalendar):

    """
    Event calendar is a basic calendar made with HTMLCalendar module.
    """

    def __init__(self, *args):
        events = args[0]
        super(EventCalendar, self).__init__()
        self.events = self.group_by_day(events)

    def formatday(self, day, weekday):
        if day != 0:
            cssclass = self.cssclasses[weekday]
            if date.today() == date(self.year, self.month, day):
                cssclass += ' today'
            if day in self.events:
                cssclass += ' filled'
                body = ['<ul>']
                for event in self.events[day]:
                    body.append('<li>')
                    body.append('<a href="%s">' % event.get_absolute_url())
                    body.append(esc(event.title))
                    body.append('</a></li>')
                body.append('<ul>')
                return self.day_cell(cssclass, '%d %s' % (day, ''.join(body)))
            return self.day_cell(cssclass, day)
        return self.day_cell('noday', '&nbsp;')

    def formatmonth(self, year, month):
        self.year, self.month = year, month
        return super(EventCalendar, self).formatmonth(year, month)

    def group_by_day(self, events):
        field = lambda event: event.meeting_date.day
        return dict(
            [(day, list(items)) for day, items in groupby(events, field)]
        )

    def day_cell(self, cssclass, body):
        return '<td class="%s">%s</td>' % (cssclass, body)

from django.shortcuts import render_to_response, get_object_or_404
from django.utils.safestring import mark_safe
from django.template import RequestContext
from django.utils import translation

from e_cidadania.apps.spaces.models import Meeting, Space
from e_cidadania.apps.cal.models import EventCalendar

def calendar(request, space_name, year, month):

    # Avoid people writing wrong numbers or any program errors.
    if int(month) not in range(1, 13):
        return render_to_response('cal/error.html',
                                  context_instance=RequestContext(request))

    place = get_object_or_404(Space, url=space_name)
    next_month = int(month) + 1
    prev_month = int(month) - 1

    meetings = Meeting.objects.order_by('meeting_date') \
                              .filter(space = place,
                                      meeting_date__year = year,
                                      meeting_date__month = month)

    cur_lang = translation.get_language()
    print cur_lang
    cal = EventCalendar(meetings, 0, cur_lang).formatmonth(int(year), int(month))
    return render_to_response('cal/calendar.html',
                              {'calendar': mark_safe(cal),
                               'nextmonth': '%02d' % next_month,
                               'prevmonth': '%02d' % prev_month,
                               'get_place': place},
                               context_instance = RequestContext(request))