from collections import defaultdict from datetime import datetime from django.conf import settings from django.contrib.auth.models import AnonymousUser from django.contrib.contenttypes.fields import GenericForeignKey from django.contrib.contenttypes.models import ContentType from django.db import models, transaction from django.utils.translation import ugettext as _ from django.utils.translation import ugettext_lazy, ugettext_noop from openslides.core.config import config from openslides.core.projector import Countdown from openslides.utils.exceptions import OpenSlidesError from openslides.utils.models import RESTModelMixin from openslides.utils.utils import to_roman class ItemManager(models.Manager): """ Customized model manager with special methods for agenda tree and numbering. """ def get_only_agenda_items(self, queryset=None): """ Generator, which yields only agenda items. Skips hidden items. """ if queryset is None: queryset = self.all() # Do not execute item.is_hidden() because this would create a lot of db queries root_items, item_children = self.get_root_and_children(only_agenda_items=True) def yield_items(items): """ Generator that yields a list of items and their children. """ for item in items: yield item yield from yield_items(item_children[item.pk]) yield from yield_items(root_items) def get_root_and_children(self, only_agenda_items=False): """ Returns a list with all root items and a dictonary where the key is an item pk and the value is a list with all children of the item. If only_agenda_items is True, the tree hides HIDDEN_ITEM. """ queryset = self.order_by('weight') item_children = defaultdict(list) root_items = [] for item in queryset: if only_agenda_items and item.type == item.HIDDEN_ITEM: continue if item.parent_id is not None: item_children[item.parent_id].append(item) else: root_items.append(item) return root_items, item_children def get_tree(self, only_agenda_items=False, include_content=False): """ Generator that yields dictonaries. Each dictonary has two keys, id and children, where id is the id of one agenda item and children is a generator that yields dictonaries like the one discribed. If only_agenda_items is True, the tree hides HIDDEN_ITEM. If include_content is True, the yielded dictonaries have no key 'id' but a key 'item' with the entire object. """ root_items, item_children = self.get_root_and_children(only_agenda_items=only_agenda_items) def get_children(items): """ Generator that yields the descibed diconaries. """ for item in items: if include_content: yield dict(item=item, children=get_children(item_children[item.pk])) else: yield dict(id=item.pk, children=get_children(item_children[item.pk])) yield from get_children(root_items) @transaction.atomic def set_tree(self, tree): """ Sets the agenda tree. The tree has to be a nested object. For example: [{"id": 1}, {"id": 2, "children": [{"id": 3}]}] """ def walk_items(tree, parent=None): """ Generator that returns each item in the tree as tuple. This tuples have tree values. The item id, the item parent and the weight of the item. """ for weight, element in enumerate(tree): yield (element['id'], parent, weight) yield from walk_items(element.get('children', []), element['id']) touched_items = set() db_items = dict((item.pk, item) for item in Item.objects.all()) for item_id, parent_id, weight in walk_items(tree): # Check that the item is only once in the tree to prevent invalid trees if item_id in touched_items: raise ValueError("Item {} is more then once in the tree.".format(item_id)) touched_items.add(item_id) try: db_item = db_items[item_id] except KeyError: raise ValueError("Item {} is not in the database.".format(item_id)) # Check if the item has changed and update it # Note: Do not use Item.objects.update, so that the items are sent # to the clients via autoupdate if db_item.parent_id != parent_id or db_item.weight != weight: db_item.parent_id = parent_id db_item.weight = weight db_item.save() @transaction.atomic def number_all(self, numeral_system='arabic'): """ Auto numbering of the agenda according to the numeral_system. Manually added item numbers will be overwritten. """ def walk_tree(tree, number=None): for index, tree_element in enumerate(tree): if numeral_system == 'roman' and number is None: item_number = to_roman(index + 1) else: item_number = str(index + 1) if number is not None: item_number = '.'.join((number, item_number)) if config['agenda_number_prefix']: item_number_tmp = "%s %s" % (config['agenda_number_prefix'], item_number) else: item_number_tmp = item_number tree_element['item'].item_number = item_number_tmp tree_element['item'].save() walk_tree(tree_element['children'], item_number) walk_tree(self.get_tree(only_agenda_items=True, include_content=True)) class Item(RESTModelMixin, models.Model): """ An Agenda Item """ objects = ItemManager() slide_callback_name = 'agenda' AGENDA_ITEM = 1 HIDDEN_ITEM = 2 ITEM_TYPE = ( (AGENDA_ITEM, ugettext_lazy('Agenda item')), (HIDDEN_ITEM, ugettext_lazy('Hidden item'))) item_number = models.CharField(blank=True, max_length=255) """ Number of agenda item. """ comment = models.TextField(null=True, blank=True) """ Optional comment to the agenda item. Will not be shoun to normal users. """ closed = models.BooleanField(default=False) """ Flag, if the item is finished. """ type = models.IntegerField( choices=ITEM_TYPE, default=AGENDA_ITEM) """ Type of the agenda item. See Item.ITEM_TYPE for more information. """ duration = models.CharField(null=True, blank=True, max_length=5) """ The intended duration for the topic. """ parent = models.ForeignKey( 'self', on_delete=models.SET_NULL, null=True, blank=True, related_name='children') """ The parent item in the agenda tree. """ weight = models.IntegerField(default=0) """ Weight to sort the item in the agenda. """ content_type = models.ForeignKey( ContentType, on_delete=models.SET_NULL, null=True, blank=True) """ Field for generic relation to a related object. Type of the object. """ object_id = models.PositiveIntegerField(null=True, blank=True) """ Field for generic relation to a related object. Id of the object. """ content_object = GenericForeignKey() """ Field for generic relation to a related object. General field to the related object. """ speaker_list_closed = models.BooleanField( default=False) """ True, if the list of speakers is closed. """ class Meta: default_permissions = () permissions = ( ('can_see', ugettext_noop("Can see agenda")), ('can_manage', ugettext_noop("Can manage agenda")), ('can_see_hidden_items', ugettext_noop("Can see hidden items and time scheduling of agenda"))) unique_together = ('content_type', 'object_id') def __str__(self): return self.title def delete(self, with_children=False): """ Delete the Item. If with_children is True, all children of the item will be deleted as well. If with_children is False, all children will be children of the parent of the item. """ if not with_children: for child in self.children.all(): child.parent = self.parent child.save() super().delete() @property def title(self): """ Return get_agenda_title() from the content_object. """ try: return self.content_object.get_agenda_title() except AttributeError: raise NotImplementedError('You have to provide a get_agenda_title ' 'method on your related model.') def is_hidden(self): """ Returns True if the type of this object itself is a hidden item or any of its ancestors has such a type. Attention! This executes one query for each ancestor of the item. """ return (self.type == self.HIDDEN_ITEM or (self.parent is not None and self.parent.is_hidden())) def get_next_speaker(self): """ Returns the speaker object of the speaker who is next. """ try: return self.speakers.filter(begin_time=None).order_by('weight')[0] except IndexError: # The list of speakers is empty. return None class SpeakerManager(models.Manager): """ Manager for Speaker model. Provides a customized add method. """ def add(self, user, item): """ Customized manager method to prevent anonymous users to be on the list of speakers and that someone is twice on one list (off coming speakers). Cares also initial sorting of the coming speakers. """ if self.filter(user=user, item=item, begin_time=None).exists(): raise OpenSlidesError( _('{user} is already on the list of speakers.').format(user=user) if isinstance(user, AnonymousUser): raise OpenSlidesError( _('An anonymous user can not be on lists of speakers.')) weight = (self.filter(item=item).aggregate( models.Max('weight'))['weight__max'] or 0) return self.create(item=item, user=user, weight=weight + 1) class Speaker(RESTModelMixin, models.Model): """ Model for the Speaker list. """ objects = SpeakerManager() user = models.ForeignKey( settings.AUTH_USER_MODEL, on_delete=models.CASCADE) """ ForeinKey to the user who speaks. """ item = models.ForeignKey( Item, on_delete=models.CASCADE, related_name='speakers') """ ForeinKey to the agenda item to which the user want to speak. """ begin_time = models.DateTimeField(null=True) """ Saves the time, when the speaker begins to speak. None, if he has not spoken yet. """ end_time = models.DateTimeField(null=True) """ Saves the time, when the speaker ends his speech. None, if he is not finished yet. """ weight = models.IntegerField(null=True) """ The sort order of the list of speakers. None, if he has already spoken. """ class Meta: default_permissions = () permissions = ( ('can_be_speaker', ugettext_noop('Can put oneself on the list of speakers')), ) def __str__(self): return str(self.user) def begin_speech(self): """ Let the user speak. Set the weight to None and the time to now. If anyone is still speaking, end his speech. """ try: current_speaker = (Speaker.objects.filter(item=self.item, end_time=None) .exclude(begin_time=None).get()) except Speaker.DoesNotExist: pass else: current_speaker.end_speech() self.weight = None self.begin_time = datetime.now() self.save() if config['agenda_couple_countdown_and_speakers']: Countdown.control(action='reset') Countdown.control(action='start') def end_speech(self): """ The speech is finished. Set the time to now. """ self.end_time = datetime.now() self.save() if config['agenda_couple_countdown_and_speakers']: Countdown.control(action='stop') def get_root_rest_element(self): """ Returns the item to this instance which is the root REST element. """ return self.item