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
  19 class Sponsor(models.Model):
  20     name = models.CharField(_('name'), max_length=120)
  21     _description = models.CharField(_('description'), blank=True, max_length=255)
  22     logo = models.ImageField(_('logo'), upload_to='sponsorzy/sponsor/logo')
  23     url = models.URLField(_('url'), blank=True, verify_exists=False)
  24
  25     def __unicode__(self):
  26         return self.name
  27
  28     def description(self):
  29         if len(self._description):
  30             return self._description
  31         else:
  32             return self.name
  33
  34
  35 class SponsorPage(models.Model):
  36     name = models.CharField(_('name'), max_length=120)
  37     sponsors = JSONField(_('sponsors'), default={})
  38     _html = models.TextField(blank=True, editable=False)
  39     sprite = models.ImageField(upload_to='sponsorzy/sprite', blank=True)
  40
  41     def populated_sponsors(self):
  42         result = []
  43         offset = 0
  44         for column in self.get_sponsors_value():
  45             result_group = {'name': column['name'], 'sponsors': []}
  46             sponsor_objects = Sponsor.objects.in_bulk(column['sponsors'])
  47             for sponsor_pk in column['sponsors']:
  48                 try:
  49                     result_group['sponsors'].append((offset, sponsor_objects[sponsor_pk]))
  50                     offset -= THUMB_HEIGHT
  51                 except KeyError:
  52                     pass
  53             result.append(result_group)
  54         return result
  55
  56     def render_sprite(self):
  57         sponsor_ids = []
  58         for column in self.get_sponsors_value():
  59             sponsor_ids.extend(column['sponsors'])
  60         sponsors = Sponsor.objects.in_bulk(sponsor_ids)
  61         sprite = Image.new('RGBA', (THUMB_WIDTH, len(sponsors) * THUMB_HEIGHT))
  62         for i, sponsor_id in enumerate(sponsor_ids):
  63             simg = Image.open(sponsors[sponsor_id].logo.path)
  64             if simg.size[0] > THUMB_WIDTH or simg.size[1] > THUMB_HEIGHT:
  65                 size = (
  66                     min(THUMB_WIDTH,
  67                         simg.size[0] * THUMB_HEIGHT / simg.size[1]),
  68                     min(THUMB_HEIGHT,
  69                         simg.size[1] * THUMB_WIDTH / simg.size[0])
  70                 )
  71                 simg = simg.resize(size, Image.ANTIALIAS)
  72             sprite.paste(simg, (
  73                     (THUMB_WIDTH - simg.size[0]) / 2,
  74                     i * THUMB_HEIGHT + (THUMB_HEIGHT - simg.size[1]) / 2,
  75                     ))
  76         imgstr = StringIO()
  77         sprite.save(imgstr, 'png')
  78
  79         if self.sprite:
  80             self.sprite.delete(save=False)
  81         self.sprite.save('sponsorzy/sprite/%s-%d.png' % (self.name, time.time()), ContentFile(imgstr.getvalue()), save=False)
  82
  83     def html(self):
  84         return self._html
  85     html = property(fget=html)
  86
  87     def save(self, *args, **kwargs):
  88         self.render_sprite()
  89         self._html = render_to_string('sponsors/page.html', {
  90             'sponsors': self.populated_sponsors(),
  91             'page': self
  92         })
  93         return super(SponsorPage, self).save(*args, **kwargs)
  94
  95     def __unicode__(self):
  96         return self.name
  97