OpenSlides/openslides/agenda/models.py

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

    Models for the agenda app.

    :copyright: 2011–2013 by OpenSlides team, see AUTHORS.
    :license: GNU GPL, see LICENSE for more details.
"""

from datetime import datetime

from django.db import models
from django.contrib.auth.models import AnonymousUser
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes import generic
from django.core.urlresolvers import reverse
from django.utils.translation import ugettext_lazy, ugettext_noop, ugettext as _

from mptt.models import MPTTModel, TreeForeignKey

from openslides.utils.exceptions import OpenSlidesError
from openslides.config.api import config
from openslides.projector.projector import SlideMixin
from openslides.projector.api import (
    register_slidemodel, get_slide_from_sid, register_slidefunc)
from openslides.utils.person.models import PersonField


class Item(MPTTModel, SlideMixin):
    """
    An Agenda Item

    MPTT-model. See http://django-mptt.github.com/django-mptt/
    """
    prefix = 'item'

    AGENDA_ITEM = 1
    ORGANIZATIONAL_ITEM = 2

    ITEM_TYPE = (
        (AGENDA_ITEM, ugettext_lazy('Agenda item')),
        (ORGANIZATIONAL_ITEM, ugettext_lazy('Organizational item')))

    title = models.CharField(null=True, max_length=255, verbose_name=ugettext_lazy("Title"))
    """
    Title of the agenda item.
    """

    text = models.TextField(null=True, blank=True, verbose_name=ugettext_lazy("Text"))
    """
    The optional text of the agenda item.
    """

    comment = models.TextField(null=True, blank=True, verbose_name=ugettext_lazy("Comment"))
    """
    Optional comment to the agenda item. Will not be shoun to normal users.
    """

    closed = models.BooleanField(default=False, verbose_name=ugettext_lazy("Closed"))
    """
    Flag, if the item is finished.
    """

    type = models.IntegerField(max_length=1, choices=ITEM_TYPE,
                               default=AGENDA_ITEM, verbose_name=ugettext_lazy("Type"))
    """
    Type of the agenda item.

    See Item.ITEM_TYPE for more information.
    """

    duration = models.CharField(null=True, blank=True, max_length=5,
                                verbose_name=ugettext_lazy("Duration (hh:mm)"))
    """
    The intended duration for the topic.
    """

    parent = TreeForeignKey('self', null=True, blank=True,
                            related_name='children')
    """
    The parent item in the agenda tree.
    """

    weight = models.IntegerField(default=0, verbose_name=ugettext_lazy("Weight"))
    """
    Weight to sort the item in the agenda.
    """

    content_type = models.ForeignKey(ContentType, 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 = generic.GenericForeignKey()
    """
    Field for generic relation to a related object. General field to the related object.
    """

    speaker_list_closed = models.BooleanField(
        default=False, verbose_name=ugettext_lazy("List of speakers is closed"))
    """
    True, if the list of speakers is closed.
    """

    class Meta:
        permissions = (
            ('can_see_agenda', ugettext_noop("Can see agenda")),
            ('can_manage_agenda', ugettext_noop("Can manage agenda")),
            ('can_see_orga_items', ugettext_noop("Can see orga items and time scheduling of agenda")))

    class MPTTMeta:
        order_insertion_by = ['weight']

    def __unicode__(self):
        return self.get_title()

    def get_absolute_url(self, link='detail'):
        """
        Return the URL to this item.

        The link can be detail, update or delete.
        """
        if link == 'detail' or link == 'view':
            return reverse('item_view', args=[str(self.id)])
        if link == 'update' or link == 'edit':
            return reverse('item_edit', args=[str(self.id)])
        if link == 'delete':
            return reverse('item_delete', args=[str(self.id)])

    def get_title(self):
        """
        Return the title of this item.
        """
        if not self.content_object:
            return self.title
        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 get_title_supplement(self):
        """
        Return a supplement for the title.
        """
        if not self.content_object:
            return ''
        try:
            return self.content_object.get_agenda_title_supplement()
        except AttributeError:
            raise NotImplementedError('You have to provide a get_agenda_title_supplement method on your related model.')

    def slide(self):
        """
        Return a map with all data for the slide.

        There are four cases:
        * summary slide
        * list of speakers
        * related item, i. e. the slide of the related object
        * normal slide of the item

        The method returns only one of them according to the config value
        'presentation_argument' and the attribute 'content_object'.
        """
        if config['presentation_argument'] == 'summary':
            data = {'title': self.get_title(),
                    'items': self.get_children().filter(type__exact=Item.AGENDA_ITEM),
                    'template': 'projector/AgendaSummary.html'}

        elif config['presentation_argument'] == 'show_list_of_speakers':
            list_of_speakers = self.get_list_of_speakers(
                old_speakers_count=config['agenda_show_last_speakers'])
            data = {'title': self.get_title(),
                    'item': self,
                    'template': 'projector/agenda_list_of_speaker.html',
                    'list_of_speakers': list_of_speakers}
        elif self.content_object:
            data = self.content_object.slide()

        else:
            data = {'item': self,
                    'title': self.get_title(),
                    'template': 'projector/AgendaText.html'}

        return data

    def set_closed(self, closed=True):
        """
        Changes the closed-status of the item.
        """
        self.closed = closed
        self.save()

    @property
    def weight_form(self):
        """
        Return the WeightForm for this item.
        """
        from openslides.agenda.forms import ItemOrderForm
        try:
            parent = self.parent.id
        except AttributeError:
            parent = 0
        initial = {
            'weight': self.weight,
            'self': self.id,
            'parent': parent,
        }
        return ItemOrderForm(initial=initial, prefix="i%d" % self.id)

    def delete(self, with_children=False):
        """
        Delete the Item.
        """
        if not with_children:
            for child in self.get_children():
                child.move_to(self.parent)
                child.save()
        super(Item, self).delete()
        Item.objects.rebuild()

    def get_list_of_speakers(self, old_speakers_count=None, coming_speakers_count=None):
        """
        Returns the list of speakers as a list of dictionaries. Each
        dictionary contains a prefix, the speaker and its type. Types
        are old_speaker, actual_speaker and coming_speaker.
        """
        speaker_query = Speaker.objects.filter(item=self)  # TODO: Why not self.speaker_set?
        list_of_speakers = []

        # Parse old speakers
        old_speakers = speaker_query.exclude(begin_time=None).exclude(end_time=None).order_by('end_time')
        if old_speakers_count is None:
            old_speakers_count = old_speakers.count()
        last_old_speakers_count = max(0, old_speakers.count() - old_speakers_count)
        old_speakers = old_speakers[last_old_speakers_count:]
        for number, speaker in enumerate(old_speakers):
            prefix = old_speakers_count - number
            speaker_dict = {
                'prefix': '-%d' % prefix,
                'speaker': speaker,
                'type': 'old_speaker',
                'first_in_group': False,
                'last_in_group': False}
            if number == 0:
                speaker_dict['first_in_group'] = True
            if number == old_speakers_count - 1:
                speaker_dict['last_in_group'] = True
            list_of_speakers.append(speaker_dict)

        # Parse actual speaker
        try:
            actual_speaker = speaker_query.filter(end_time=None).exclude(begin_time=None).get()
        except Speaker.DoesNotExist:
            pass
        else:
            list_of_speakers.append({
                'prefix': '0',
                'speaker': actual_speaker,
                'type': 'actual_speaker',
                'first_in_group': True,
                'last_in_group': True})

        # Parse coming speakers
        coming_speakers = speaker_query.filter(begin_time=None).order_by('weight')
        if coming_speakers_count is None:
            coming_speakers_count = coming_speakers.count()
        coming_speakers = coming_speakers[:max(0, coming_speakers_count)]
        for number, speaker in enumerate(coming_speakers):
            speaker_dict = {
                'prefix': number + 1,
                'speaker': speaker,
                'type': 'coming_speaker',
                'first_in_group': False,
                'last_in_group': False}
            if number == 0:
                speaker_dict['first_in_group'] = True
            if number == coming_speakers_count - 1:
                speaker_dict['last_in_group'] = True
            list_of_speakers.append(speaker_dict)

        return list_of_speakers

    def get_next_speaker(self):
        """
        Returns the speaker object of the person who is next.
        """
        try:
            return self.speaker_set.filter(begin_time=None).order_by('weight')[0]
        except IndexError:
            # The list of speakers is empty.
            return None


class SpeakerManager(models.Manager):
    def add(self, person, item):
        if self.filter(person=person, item=item, begin_time=None).exists():
            raise OpenSlidesError(_(
                '%(person)s is already on the list of speakers of item %(id)s.')
                % {'person': person, 'id': item.id})
        if isinstance(person, 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, person=person, weight=weight + 1)


class Speaker(models.Model):
    """
    Model for the Speaker list.
    """

    objects = SpeakerManager()

    person = PersonField()
    """
    ForeinKey to the person who speaks.
    """

    item = models.ForeignKey(Item)
    """
    ForeinKey to the AgendaItem to which the person 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 speach. 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:
        permissions = (
            ('can_be_speaker', ugettext_noop('Can put oneself on the list of speakers')),
        )

    def __unicode__(self):
        return unicode(self.person)

    def get_absolute_url(self, link='detail'):
        if link == 'detail' or link == 'view':
            return self.person.get_absolute_url('detail')
        if link == 'delete':
            return reverse('agenda_speaker_delete',
                           args=[self.item.pk, self.pk])

    def begin_speach(self):
        """
        Let the person speak.

        Set the weight to None and the time to now. If anyone is still
        speaking, end his speach.
        """
        try:
            actual_speaker = Speaker.objects.filter(item=self.item, end_time=None).exclude(begin_time=None).get()
        except Speaker.DoesNotExist:
            pass
        else:
            actual_speaker.end_speach()
        self.weight = None
        self.begin_time = datetime.now()
        self.save()

    def end_speach(self):
        """
        The speach is finished. Set the time to now.
        """
        self.end_time = datetime.now()
        self.save()