src/sponsors/models.py

   1 # This file is part of Wolne Lektury, licensed under GNU Affero GPLv3 or later.
   2 # Copyright © Fundacja Wolne Lektury. See NOTICE for more information.
   3 #
   4 import json
   5 import time
   6 from io import BytesIO
   7 from django.core.cache import cache
   8 from django.db import models
   9 from django.template.loader import render_to_string
  10 from PIL import Image
  11
  12 from django.core.files.base import ContentFile
  13
  14 THUMB_WIDTH = 120
  15 THUMB_HEIGHT = 120
  16
  17
  18 class Sponsor(models.Model):
  19     name = models.CharField('nazwa', max_length=120)
  20     _description = models.CharField('opis', blank=True, max_length=255)
  21     logo = models.ImageField('logo', upload_to='sponsorzy/sponsor/logo')
  22     url = models.URLField('url', blank=True)
  23
  24     def __str__(self):
  25         return self.name
  26
  27     def save(self, *args, **kwargs):
  28         super().save(*args, **kwargs)
  29         for page in SponsorPage.objects.all():
  30             page.save()
  31
  32     def description(self):
  33         if len(self._description):
  34             return self._description
  35         else:
  36             return self.name
  37
  38
  39 class SponsorPage(models.Model):
  40     name = models.CharField('nazwa', max_length=120)
  41     sponsors = models.TextField('sponsorzy', default='{}')
  42     _html = models.TextField(blank=True, editable=False)
  43     sprite = models.ImageField(upload_to='sponsorzy/sprite', blank=True)
  44
  45     def get_sponsors_json(self):
  46         return json.loads(self.sponsors or '[]')
  47
  48     def populated_sponsors(self):
  49         result = []
  50         offset = 0
  51         for column in self.get_sponsors_json():
  52             result_group = {'name': column['name'], 'sponsors': []}
  53             sponsor_objects = Sponsor.objects.in_bulk(column['sponsors'])
  54             for sponsor_pk in column['sponsors']:
  55                 try:
  56                     result_group['sponsors'].append((offset, sponsor_objects[sponsor_pk]))
  57                     offset -= THUMB_HEIGHT
  58                 except KeyError:
  59                     pass
  60             if result_group['sponsors']:
  61                 result.append(result_group)
  62         return result
  63
  64     def render_sprite(self):
  65         sponsor_ids = []
  66         for column in self.get_sponsors_json():
  67             sponsor_ids.extend(column['sponsors'])
  68         sponsors = Sponsor.objects.in_bulk(sponsor_ids)
  69         sprite = Image.new('RGBA', (THUMB_WIDTH, len(sponsors) * THUMB_HEIGHT))
  70         for i, sponsor_id in enumerate(sponsor_ids):
  71             simg = Image.open(sponsors[sponsor_id].logo.path)
  72             if simg.size[0] > THUMB_WIDTH or simg.size[1] > THUMB_HEIGHT:
  73                 size = (
  74                     min(THUMB_WIDTH,
  75                         round(simg.size[0] * THUMB_HEIGHT / simg.size[1])),
  76                     min(THUMB_HEIGHT,
  77                         round(simg.size[1] * THUMB_WIDTH / simg.size[0]))
  78                 )
  79                 simg = simg.resize(size, Image.ANTIALIAS)
  80             sprite.paste(simg, (
  81                     round((THUMB_WIDTH - simg.size[0]) / 2),
  82                     round(i * THUMB_HEIGHT + (THUMB_HEIGHT - simg.size[1]) / 2),
  83                     ))
  84         imgstr = BytesIO()
  85         sprite.save(imgstr, 'png')
  86
  87         if self.sprite:
  88             self.sprite.delete(save=False)
  89         self.sprite.save('sponsorzy/sprite/%s-%d.png' % (
  90             self.name, time.time()), ContentFile(imgstr.getvalue()), save=False)
  91
  92     def html(self):
  93         return self._html
  94     html = property(fget=html)
  95
  96     def save(self, *args, **kwargs):
  97         self.render_sprite()
  98         self._html = render_to_string('sponsors/page.html', {
  99             'sponsors': self.populated_sponsors(),
 100             'page': self
 101         })
 102         ret = super(SponsorPage, self).save(*args, **kwargs)
 103         cache.delete('sponsor_page:' + self.name)
 104         return ret
 105
 106     def __str__(self):
 107         return self.name