#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
    openslides.agenda.views
    ~~~~~~~~~~~~~~~~~~~~~~~

    Views for the agenda app.

    :copyright: 2011, 2012 by the OpenSlides team, see AUTHORS.
    :license: GNU GPL, see LICENSE for more details.
"""
from reportlab.platypus import Paragraph

from django.core.context_processors import csrf
from django.core.urlresolvers import reverse
from django.contrib import messages
from django.db import transaction
from django.db.models import Model
from django.utils.translation import ugettext as _, ugettext_lazy
from django.views.generic.detail import SingleObjectMixin

from openslides.utils.pdf import stylesheet
from openslides.utils.views import (TemplateView, RedirectView, UpdateView,
    CreateView, DeleteView, PDFView, DetailView)
from openslides.utils.template import Tab
from openslides.utils.utils import html_strong

from openslides.config.models import config

from openslides.projector.api import get_active_slide
from openslides.projector.projector import Widget, SLIDE

from openslides.agenda.models import Item
from openslides.agenda.forms import ItemOrderForm, ItemForm


class Overview(TemplateView):
    """
    Show all agenda items, and update there range via post.
    """
    permission_required = 'agenda.can_see_agenda'
    template_name = 'agenda/overview.html'

    def get_context_data(self, **kwargs):
        context = super(Overview, self).get_context_data(**kwargs)
        context.update({
            'items': Item.objects.all(),
            'active_sid': get_active_slide(only_sid=True),
        })
        return context

    @transaction.commit_manually
    def post(self, request, *args, **kwargs):
        context = self.get_context_data(**kwargs)
        if not request.user.has_perm('agenda.can_manage_agenda'):
            messages.error(request,
                _('You are not authorized to manage the agenda.'))
            return self.render_to_response(context)
        transaction.commit()
        for item in Item.objects.all():
            form = ItemOrderForm(request.POST, prefix="i%d" % item.id)
            if form.is_valid():
                try:
                    parent = Item.objects.get(id=form.cleaned_data['parent'])
                except Item.DoesNotExist:
                    parent = None
                item.weight = form.cleaned_data['weight']
                item.parent = parent
                Model.save(item)
            else:
                transaction.rollback()
                messages.error(request,
                    _('Errors when reordering of the agenda'))
                return self.render_to_response(context)
        Item.objects.rebuild()
        # TODO: assure, that it is a valid tree
        transaction.commit()
        return self.render_to_response(context)


class View(DetailView):
    """
    Show an agenda item.
    """
    permission_required = 'agenda.can_see_agenda'
    template_name = 'agenda/view.html'
    model = Item
    context_object_name = 'item'


class SetClosed(RedirectView, SingleObjectMixin):
    """
    Close or open an item.
    """
    permission_required = 'agenda.can_manage_agenda'
    allow_ajax = True
    url = 'item_overview'
    model = Item

    def get_ajax_context(self, **kwargs):
        context = super(SetClosed, self).get_ajax_context(**kwargs)
        closed = kwargs['closed']
        if closed:
            link = reverse('item_open', args=[self.object.id])
        else:
            link = reverse('item_close', args=[self.object.id])
        context.update({
            'closed': kwargs['closed'],
            'link': link,
        })
        return context

    def pre_redirect(self, request, *args, **kwargs):
        self.object = self.get_object()
        closed = kwargs['closed']
        self.object.set_closed(closed)
        return super(SetClosed, self).pre_redirect(request, *args, **kwargs)


class ItemUpdate(UpdateView):
    """
    Update an existing item.
    """
    permission_required = 'agenda.can_manage_agenda'
    template_name = 'agenda/edit.html'
    model = Item
    context_object_name = 'item'
    form_class = ItemForm
    success_url = 'item_overview'
    apply_url = 'item_edit'

    def get_success_url(self):
        messages.success(self.request,
            _("Item %s was successfully modified.") \
            % html_strong(self.request.POST['title']))
        if 'apply' in self.request.POST:
            return ''
        return reverse(super(UpdateView, self).get_success_url())


class ItemCreate(CreateView):
    """
    Create a new item.
    """
    permission_required = 'agenda.can_manage_agenda'
    template_name = 'agenda/edit.html'
    model = Item
    context_object_name = 'item'
    form_class = ItemForm
    success_url = 'item_overview'
    apply_url = 'item_edit'

    def get_success_url(self):
        messages.success(self.request,
            _("Item %s was successfully created.") \
            % html_strong(self.request.POST['title']))
        if 'apply' in self.request.POST:
            return reverse(self.get_apply_url(), args=[self.object.id])
        return reverse(super(CreateView, self).get_success_url())


class ItemDelete(DeleteView):
    """
    Delete an item.
    """
    permission_required = 'agenda.can_manage_agenda'
    model = Item
    url = 'item_overview'

    def get_answer_options(self):
        if self.object.children.exists():
            return [('all', _("Yes, with all child items."))] + self.answer_options
        else:
            return self.answer_options

    def pre_post_redirect(self, request, *args, **kwargs):
        if self.get_answer() == 'all':
            self.object.delete(with_children=True)
            messages.success(request,
                _("Item %s and his children were successfully deleted.") \
                % html_strong(self.object))
        elif self.get_answer() == 'yes':
            self.object.delete(with_children=False)
            messages.success(request,
                _("Item %s was successfully deleted.") \
                % html_strong(self.object))


class AgendaPDF(PDFView):
    """
    Create a full agenda-PDF.
    """
    permission_required = 'agenda.can_see_agenda'
    filename = ugettext_lazy('Agenda')
    document_title = ugettext_lazy('Agenda')

    def append_to_pdf(self, story):
        for item in Item.objects.all():
            ancestors = item.get_ancestors()
            if ancestors:
                space = " " * 6 * ancestors.count()
                story.append(Paragraph("%s%s" % (space, item.get_title()),
                    stylesheet['Subitem']))
            else:
                story.append(Paragraph(item.get_title(), stylesheet['Item']))


def register_tab(request):
    """
    register the agenda tab.
    """
    selected = request.path.startswith('/agenda/')
    return Tab(
        title=_('Agenda'),
        app='agenda',
        url=reverse('item_overview'),
        permission=request.user.has_perm('agenda.can_see_agenda')
            or request.user.has_perm('agenda.can_manage_agenda'),
        selected=selected,
    )


def get_widgets(request):
    """
    return the agenda widget for the projector-tab.
    """
    return [
        Widget(
            name='agenda',
            template='agenda/widget.html',
            context={
                'agenda': SLIDE['agenda'],
                'items': Item.objects.all()},
            permission_required='agenda.can_manage_agenda')]