try:

        speaker = proposal.additional_speakers.get(user=request.user)

    except ObjectDoesNotExist:

        return HttpResponseForbidden()

    if request.method == "POST":

        proposal.additional_speakers.remove(speaker)

        # @@@ fire off email to submitter and other speakers

        messages.success(request, "You are no longer speaking on %s" % proposal.title)

        return redirect("speaker_dashboard")

    ctx = {

        "proposal": proposal,

    }

    return render(request, "proposals/proposal_leave.html", ctx)

@login_required

def proposal_pending_join(request, pk):

    proposal = get_object_or_404(ProposalBase, pk=pk)

    speaking = get_object_or_404(AdditionalSpeaker, speaker=request.user.speaker_profile, proposalbase=proposal)

    if speaking.status == AdditionalSpeaker.SPEAKING_STATUS_PENDING:

        speaking.status = AdditionalSpeaker.SPEAKING_STATUS_ACCEPTED

        speaking.save()

        messages.success(request, "You have accepted the invitation to join %s" % proposal.title)

        return redirect("dashboard")

    else:

        return redirect("dashboard")

@login_required

def proposal_pending_decline(request, pk):

    proposal = get_object_or_404(ProposalBase, pk=pk)

    speaking = get_object_or_404(AdditionalSpeaker, speaker=request.user.speaker_profile, proposalbase=proposal)

    if speaking.status == AdditionalSpeaker.SPEAKING_STATUS_PENDING:

        speaking.status = AdditionalSpeaker.SPEAKING_STATUS_DECLINED

        speaking.save()

        messages.success(request, "You have declined to speak on %s" % proposal.title)

        return redirect("dashboard")

    else:

        return redirect("dashboard")

@login_required

def document_create(request, proposal_pk):

    queryset = ProposalBase.objects.select_related("speaker")

    proposal = get_object_or_404(queryset, pk=proposal_pk)

    proposal = ProposalBase.objects.get_subclass(pk=proposal.pk)

    if request.method == "POST":

        form = SupportingDocumentCreateForm(request.POST, request.FILES)

        if form.is_valid():

            document = form.save(commit=False)

            document.proposal = proposal

            document.uploaded_by = request.user

            document.save()

            return redirect("proposal_detail", proposal.pk)

    else:

        form = SupportingDocumentCreateForm()

    return render(request, "proposals/document_create.html", {

        "proposal": proposal,

        "form": form,

    })

@login_required

def document_download(request, pk, *args):

    document = get_object_or_404(SupportingDocument, pk=pk)

    if getattr(settings, "USE_X_ACCEL_REDIRECT", False):

        response = HttpResponse()

        response["X-Accel-Redirect"] = document.file.url

        # delete content-type to allow Gondor to determine the filetype and

        # we definitely don't want Django's crappy default :-)

        del response["content-type"]

    else:

        response = static.serve(request, document.file.name, document_root=settings.MEDIA_ROOT)

    return response

@login_required

def document_delete(request, pk):

    document = get_object_or_404(SupportingDocument, pk=pk, uploaded_by=request.user)

    proposal_pk = document.proposal.pk

    if request.method == "POST":

        document.delete()

    return redirect("proposal_detail", proposal_pk)