--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/potd/models.py	Sat May 05 17:10:48 2012 -0500
@@ -0,0 +1,177 @@
+"""
+Models for the Photo Of The Day (POTD) application.
+
+"""
+import datetime
+import os
+from PIL import ImageFile
+from PIL import Image
+try:
+   from cStringIO import StringIO
+except:
+   from StringIO import StringIO
+
+from django.db import models
+from django.contrib.auth.models import User
+from django.core.files.base import ContentFile
+
+POTD_THUMB_WIDTH = 120
+
+def scale_image(image):
+    (w, h) = image.size
+    if w <= POTD_THUMB_WIDTH:
+        return image
+    scale_factor = float(POTD_THUMB_WIDTH) / w
+    new_height = int(scale_factor * h)
+    return image.resize((POTD_THUMB_WIDTH, new_height), Image.ANTIALIAS)
+
+
+class Photo(models.Model):
+    """Model to represent a POTD"""
+    photo = models.ImageField(upload_to='potd/%Y/%m/%d')
+    thumb = models.ImageField(upload_to='potd/%Y/%m/%d/thumbs', blank=True, null=True)
+    caption = models.CharField(max_length=128)
+    description = models.TextField()
+    user = models.ForeignKey(User)
+    date_added = models.DateField()
+    potd_count = models.IntegerField(default=0)
+
+    class Meta:
+        ordering = ('-date_added', '-caption')
+
+    def __unicode__(self):
+        return u'%s (%s)' % (self.caption, self.pk)
+
+    @models.permalink
+    def get_absolute_url(self):
+        return ('potd-archive', [str(self.id)])
+
+    def save(self, *args, **kwargs):
+        if not self.pk:
+            self.generate_thumb()
+            self.date_added = datetime.datetime.now()
+
+        super(Photo, self).save(*args, **kwargs)
+
+    def can_comment_on(self):
+        return Current.objects.get_current_id() == self.id
+
+    def generate_thumb(self):
+        if self.thumb:
+            self.thumb.delete(save=False)
+
+        parser = ImageFile.Parser()
+        for chunk in self.photo.chunks():
+            parser.feed(chunk)
+        image = parser.close()
+        format = image.format
+        image = scale_image(image)
+        s = StringIO()
+        image.save(s, format)
+        thumb_name = os.path.basename(self.photo.path)
+        self.thumb.save(thumb_name, ContentFile(s.getvalue()), save=False)
+
+    def ogp_tags(self):
+        """
+        Returns a dict of Open Graph Protocol meta tags.
+
+        """
+        desc = "Photo of the day: %s." % self.caption
+        return {
+            'og:title': self.caption,
+            'og:type': 'article',
+            'og:url': self.get_absolute_url(),
+            'og:image': self.photo.url,
+            'og:description': desc,
+        }
+
+
+class CurrentManager(models.Manager):
+    """
+    Manager for the Current model.
+
+    """
+    def get_current_photo(self):
+        """
+        Retrieves the current photo object from the current record.
+
+        """
+        try:
+            c = self.get(pk=1)
+            return c.potd
+        except Current.DoesNotExist:
+            return None
+
+    def get_current_id(self):
+        """
+        Returns the ID of the current POTD from the current record.
+
+        """
+        potd = self.get_current_photo()
+        if potd is not None:
+            return potd.pk
+        return None
+
+
+class Current(models.Model):
+    """This model simply stores the current POTD."""
+    potd = models.ForeignKey(Photo)
+
+    objects = CurrentManager()
+
+    def __unicode__(self):
+        return self.potd.__unicode__()
+
+    class Meta:
+        verbose_name_plural = 'Current'
+
+
+class SequenceManager(models.Manager):
+    """
+    Manager for the Sequence model.
+
+    """
+    def insert_photo(self, photo_id):
+        """
+        Inserts the given photo_id just after the current photo so it
+        will appear as tomorrow's POTD.
+
+        """
+        current = Current.objects.get_current_id()
+        if current is not None:
+            s = self.get(pk=1)
+            seq = [int(x) for x in s.seq.split(',')]
+            if photo_id not in seq:
+                i = seq.index(current)
+                seq.insert(i + 1, photo_id)
+                s.seq = ','.join([str(x) for x in seq])
+                s.save()
+
+    def remove_photo(self, photo_id):
+        """
+        Removes a given photo id from the sequence of photos.
+
+        """
+        try:
+            s = self.get(pk=1)
+        except Sequence.DoesNotExist:
+            pass
+        else:
+            seq = [int(x) for x in s.seq.split(',')]
+            if photo_id in seq:
+                seq.remove(photo_id)
+                s.seq = ','.join([str(x) for x in seq])
+                s.save()
+
+
+class Sequence(models.Model):
+    """This model stores the sequence of photos for the POTD."""
+    seq = models.CommaSeparatedIntegerField(max_length=4096)
+
+    objects = SequenceManager()
+
+    def __unicode__(self):
+        return u'POTD Sequence %d' % self.id
+
+    class Meta:
+        verbose_name_plural = 'Sequence'