def transition(request, document_id):
document = Document.objects.get(pk=document_id)
if request.method != 'POST':
return HttpResponseRedirect(reverse('todo_detail', args=[document_id]))
form = PartialDocumentForm(request.POST)
if not form.is_valid():
versionForm = PartialVersionForm()
attachmentForm = PartialAttachmentForm()
documentForm = form
return render(request, 'documents/todo_detail.html', locals())
document.transitionTo(form.cleaned_data['state'])
return HttpResponseRedirect(reverse('todo_index'))
