--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/forums/views/subscriptions.py	Sat May 05 17:10:48 2012 -0500
@@ -0,0 +1,122 @@
+"""This module handles the subscriptions of users to forum topics."""
+from django.conf import settings
+from django.contrib.auth.decorators import login_required
+from django.contrib.sites.models import Site
+from django.core.paginator import InvalidPage
+from django.core.urlresolvers import reverse
+from django.http import HttpResponseRedirect
+from django.http import Http404
+from django.template.loader import render_to_string
+from django.shortcuts import get_object_or_404
+from django.shortcuts import render_to_response
+from django.template import RequestContext
+from django.views.decorators.http import require_POST
+
+from forums.models import Topic
+import forums.permissions as perms
+from core.functions import send_mail
+from core.paginator import DiggPaginator
+
+
+def notify_topic_subscribers(post, defer=True):
+    """
+    The argument post is a newly created post. Send out an email
+    notification to all subscribers of the post's parent Topic.
+
+    The defer flag is passed to core.functions.send_mail. If True, the mail is
+    sent on a Celery task. If False, the mail is sent on the caller's thread.
+    """
+    topic = post.topic
+    recipients = topic.subscribers.exclude(id=post.user.id).values_list(
+            'email', flat=True)
+
+    if recipients:
+        site = Site.objects.get_current()
+        subject = "[%s] Topic Reply: %s" % (site.name, topic.name)
+        url_prefix = "http://%s" % site.domain
+        post_url = url_prefix + post.get_absolute_url()
+        unsubscribe_url = url_prefix + reverse("forums-manage_subscriptions")
+        msg = render_to_string("forums/topic_notify_email.txt", {
+                'poster': post.user.username,
+                'topic_name': topic.name,
+                'message': post.body,
+                'post_url': post_url,
+                'unsubscribe_url': unsubscribe_url,
+                })
+        for recipient in recipients:
+            send_mail(subject, msg, settings.DEFAULT_FROM_EMAIL, [recipient],
+                    defer=defer)
+
+
+@login_required
+@require_POST
+def subscribe_topic(request, topic_id):
+    """Subscribe the user to the requested topic."""
+    topic = get_object_or_404(Topic.objects.select_related(), id=topic_id)
+    if perms.can_access(topic.forum.category, request.user):
+        topic.subscribers.add(request.user)
+        return HttpResponseRedirect(
+            reverse("forums-subscription_status", args=[topic.id]))
+    raise Http404
+
+
+@login_required
+@require_POST
+def unsubscribe_topic(request, topic_id):
+    """Unsubscribe the user to the requested topic."""
+    topic = get_object_or_404(Topic, id=topic_id)
+    topic.subscribers.remove(request.user)
+    return HttpResponseRedirect(
+        reverse("forums-subscription_status", args=[topic.id]))
+
+
+@login_required
+def subscription_status(request, topic_id):
+    """Display the subscription status for the given topic."""
+    topic = get_object_or_404(Topic.objects.select_related(), id=topic_id)
+    is_subscribed = request.user in topic.subscribers.all()
+    return render_to_response('forums/subscription_status.html', {
+        'topic': topic,
+        'is_subscribed': is_subscribed,
+        },
+        context_instance=RequestContext(request))
+
+
+@login_required
+def manage_subscriptions(request):
+    """Display a user's topic subscriptions, and allow them to be deleted."""
+
+    user = request.user
+    if request.method == "POST":
+        if request.POST.get('delete_all'):
+            user.subscriptions.clear()
+        else:
+            delete_ids = request.POST.getlist('delete_ids')
+            try:
+                delete_ids = [int(id) for id in delete_ids]
+            except ValueError:
+                raise Http404
+
+            for topic in user.subscriptions.filter(id__in=delete_ids):
+                user.subscriptions.remove(topic)
+
+        return HttpResponseRedirect(reverse("forums-manage_subscriptions"))
+
+    page_num = request.GET.get('page', 1)
+    topics = user.subscriptions.select_related().order_by('-update_date')
+    paginator = DiggPaginator(topics, 20, body=5, tail=2, margin=3, padding=2)
+    try:
+        page_num = int(page_num)
+    except ValueError:
+        page_num = 1
+    try:
+        page = paginator.page(page_num)
+    except InvalidPage:
+        raise Http404
+
+    return render_to_response('forums/manage_topics.html', {
+        'page_title': 'Topic Subscriptions',
+        'description': 'The forum topics you are currently subscribed to are listed below.',
+        'page': page,
+        },
+        context_instance=RequestContext(request))