apps/sponsors/models.py

   1 # -*- coding: utf-8 -*-
   2 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
   3 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
   4 #
   5 import time
   6 from StringIO import StringIO
   7 from django.db import models
   8 from django.utils.translation import ugettext_lazy as _
   9 from django.template.loader import render_to_string
  10 from PIL import Image
  11
  12 from sponsors.fields import JSONField
  13 from django.core.files.base import ContentFile
  14
  15 THUMB_WIDTH=120
  16 THUMB_HEIGHT=120
  17
  18 class Sponsor(models.Model):
  19     name = models.CharField(_('name'), max_length=120)
  20     _description = models.CharField(_('description'), blank=True, max_length=255)
  21     logo = models.ImageField(_('logo'), upload_to='sponsorzy/sponsor/logo')
  22     url = models.URLField(_('url'), blank=True, verify_exists=False)
  23
  24     def __unicode__(self):
  25         return self.name
  26
  27     def description(self):
  28         if len(self._description):
  29             return self._description
  30         else:
  31             return self.name
  32
  33
  34 class SponsorPage(models.Model):
  35     name = models.CharField(_('name'), max_length=120)
  36     sponsors = JSONField(_('sponsors'), default={})
  37     _html = models.TextField(blank=True, editable=False)
  38     sprite = models.ImageField(upload_to='sponsorzy/sprite', blank=True)
  39
  40     def populated_sponsors(self):
  41         result = []
  42         offset = 0
  43         for column in self.get_sponsors_value():
  44             result_group = {'name': column['name'], 'sponsors': []}
  45             sponsor_objects = Sponsor.objects.in_bulk(column['sponsors'])
  46             for sponsor_pk in column['sponsors']:
  47                 try:
  48                     result_group['sponsors'].append((offset, sponsor_objects[sponsor_pk]))
  49                     offset -= THUMB_HEIGHT
  50                 except KeyError:
  51                     pass
  52             result.append(result_group)
  53         return result
  54
  55     def render_sprite(self):
  56         sponsor_ids = []
  57         for column in self.get_sponsors_value():
  58             sponsor_ids.extend(column['sponsors'])
  59         sponsors = Sponsor.objects.in_bulk(sponsor_ids)
  60         sprite = Image.new('RGBA', (THUMB_WIDTH, len(sponsors)*THUMB_HEIGHT))
  61         for i, sponsor_id in enumerate(sponsor_ids):
  62             simg = Image.open(sponsors[sponsor_id].logo.path)
  63             if simg.size[0] > THUMB_WIDTH or simg.size[1] > THUMB_HEIGHT:
  64                 size = (
  65                     min(THUMB_WIDTH,
  66                         simg.size[0] * THUMB_HEIGHT / simg.size[1]),
  67                     min(THUMB_HEIGHT,
  68                         simg.size[1] * THUMB_WIDTH / simg.size[0])
  69                 )
  70                 simg = simg.resize(size, Image.ANTIALIAS)
  71             sprite.paste(simg, (
  72                     (THUMB_WIDTH - simg.size[0]) / 2,
  73                     i * THUMB_HEIGHT + (THUMB_HEIGHT - simg.size[1]) / 2,
  74                     ))
  75         imgstr = StringIO()
  76         sprite.save(imgstr, 'png')
  77
  78         if self.sprite:
  79             self.sprite.delete(save=False)
  80         self.sprite.save('sponsorzy/sprite/%s-%d.png' % (self.name, time.time()), ContentFile(imgstr.getvalue()), save=False)
  81
  82     def html(self):
  83         return self._html
  84     html = property(fget=html)
  85
  86     def save(self, *args, **kwargs):
  87         self.render_sprite()
  88         self._html = render_to_string('sponsors/page.html', {
  89             'sponsors': self.populated_sponsors(),
  90             'page': self
  91         })
  92         return super(SponsorPage, self).save(*args, **kwargs)
  93
  94     def __unicode__(self):
  95         return self.name
  96