models.py

# -*- coding:utf-8 -*
#
# Copyright 2016,2017,2018
# - Skia <skia@libskia.so>
# - Sli <antoine@bartuccio.fr>
#
# Ce fichier fait partie du site de l'Association des Étudiants de l'UTBM,
# http://ae.utbm.fr.
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License a published by the Free Software
# Foundation; either version 3 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Sofware Foundation, Inc., 59 Temple
# Place - Suite 330, Boston, MA 02111-1307, USA.
#
#
import importlib

from django.db import models
from django.core.mail import send_mail
from django.contrib.auth.models import (
    AbstractBaseUser,
    PermissionsMixin,
    UserManager,
    Group as AuthGroup,
    GroupManager as AuthGroupManager,
    AnonymousUser as AuthAnonymousUser,
)
from django.utils.translation import ugettext_lazy as _
from django.utils import timezone
from django.core import validators
from django.core.exceptions import ValidationError, PermissionDenied
from django.core.urlresolvers import reverse
from django.conf import settings
from django.db import transaction
from django.contrib.staticfiles.storage import staticfiles_storage
from django.utils.html import escape
from django.utils.functional import cached_property

import os

from phonenumber_field.modelfields import PhoneNumberField

from datetime import datetime, timedelta, date

import unicodedata


class RealGroupManager(AuthGroupManager):
    def get_queryset(self):
        return super(RealGroupManager, self).get_queryset().filter(is_meta=False)


class MetaGroupManager(AuthGroupManager):
    def get_queryset(self):
        return super(MetaGroupManager, self).get_queryset().filter(is_meta=True)


class Group(AuthGroup):
    is_meta = models.BooleanField(
        _("meta group status"),
        default=False,
        help_text=_("Whether a group is a meta group or not"),
    )
    description = models.CharField(_("description"), max_length=60)

    class Meta:
        ordering = ["name"]

    def get_absolute_url(self):
        """
        This is needed for black magic powered UpdateView's children
        """
        return reverse("core:group_list")


class MetaGroup(Group):
    objects = MetaGroupManager()

    class Meta:
        proxy = True

    def __init__(self, *args, **kwargs):
        super(MetaGroup, self).__init__(*args, **kwargs)
        self.is_meta = True


class RealGroup(Group):
    objects = RealGroupManager()

    class Meta:
        proxy = True


def validate_promo(value):
    start_year = settings.SITH_SCHOOL_START_YEAR
    delta = (date.today() + timedelta(days=180)).year - start_year
    if value < 0 or delta < value:
        raise ValidationError(
            _("%(value)s is not a valid promo (between 0 and %(end)s)"),
            params={"value": value, "end": delta},
        )


class User(AbstractBaseUser):
    """
    Defines the base user class, useable in every app

    This is almost the same as the auth module AbstractUser since it inherits from it,
    but some fields are required, and the username is generated automatically with the
    name of the user (see generate_username()).

    Added field: nick_name, date_of_birth
    Required fields: email, first_name, last_name, date_of_birth
    """

    username = models.CharField(
        _("username"),
        max_length=254,
        unique=True,
        help_text=_(
            "Required. 254 characters or fewer. Letters, digits and ./+/-/_ only."
        ),
        validators=[
            validators.RegexValidator(
                r"^[\w.+-]+$",
                _(
                    "Enter a valid username. This value may contain only "
                    "letters, numbers "
                    "and ./+/-/_ characters."
                ),
            )
        ],
        error_messages={"unique": _("A user with that username already exists.")},
    )
    first_name = models.CharField(_("first name"), max_length=64)
    last_name = models.CharField(_("last name"), max_length=64)
    email = models.EmailField(_("email address"), unique=True)
    date_of_birth = models.DateField(_("date of birth"), blank=True, null=True)
    nick_name = models.CharField(_("nick name"), max_length=64, null=True, blank=True)
    is_staff = models.BooleanField(
        _("staff status"),
        default=False,
        help_text=_("Designates whether the user can log into this admin site."),
    )
    is_active = models.BooleanField(
        _("active"),
        default=True,
        help_text=_(
            "Designates whether this user should be treated as active. "
            "Unselect this instead of deleting accounts."
        ),
    )
    date_joined = models.DateField(_("date joined"), auto_now_add=True)
    last_update = models.DateTimeField(_("last update"), auto_now=True)
    is_superuser = models.BooleanField(
        _("superuser"),
        default=False,
        help_text=_("Designates whether this user is a superuser. "),
    )
    groups = models.ManyToManyField(RealGroup, related_name="users", blank=True)
    home = models.OneToOneField(
        "SithFile",
        related_name="home_of",
        verbose_name=_("home"),
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
    )
    profile_pict = models.OneToOneField(
        "SithFile",
        related_name="profile_of",
        verbose_name=_("profile"),
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
    )
    avatar_pict = models.OneToOneField(
        "SithFile",
        related_name="avatar_of",
        verbose_name=_("avatar"),
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
    )
    scrub_pict = models.OneToOneField(
        "SithFile",
        related_name="scrub_of",
        verbose_name=_("scrub"),
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
    )
    sex = models.CharField(
        _("sex"),
        max_length=10,
        choices=[("MAN", _("Man")), ("WOMAN", _("Woman"))],
        default="MAN",
    )
    tshirt_size = models.CharField(
        _("tshirt size"),
        max_length=5,
        choices=[
            ("-", _("-")),
            ("XS", _("XS")),
            ("S", _("S")),
            ("M", _("M")),
            ("L", _("L")),
            ("XL", _("XL")),
            ("XXL", _("XXL")),
            ("XXXL", _("XXXL")),
        ],
        default="-",
    )
    role = models.CharField(
        _("role"),
        max_length=15,
        choices=[
            ("STUDENT", _("Student")),
            ("ADMINISTRATIVE", _("Administrative agent")),
            ("TEACHER", _("Teacher")),
            ("AGENT", _("Agent")),
            ("DOCTOR", _("Doctor")),
            ("FORMER STUDENT", _("Former student")),
            ("SERVICE", _("Service")),
        ],
        blank=True,
        default="",
    )
    department = models.CharField(
        _("department"),
        max_length=15,
        choices=settings.SITH_PROFILE_DEPARTMENTS,
        default="NA",
        blank=True,
    )
    dpt_option = models.CharField(
        _("dpt option"), max_length=32, blank=True, default=""
    )
    semester = models.CharField(_("semester"), max_length=5, blank=True, default="")
    quote = models.CharField(_("quote"), max_length=256, blank=True, default="")
    school = models.CharField(_("school"), max_length=80, blank=True, default="")
    promo = models.IntegerField(
        _("promo"), validators=[validate_promo], null=True, blank=True
    )
    forum_signature = models.TextField(
        _("forum signature"), max_length=256, blank=True, default=""
    )
    second_email = models.EmailField(_("second email address"), null=True, blank=True)
    phone = PhoneNumberField(_("phone"), null=True, blank=True)
    parent_phone = PhoneNumberField(_("parent phone"), null=True, blank=True)
    address = models.CharField(_("address"), max_length=128, blank=True, default="")
    parent_address = models.CharField(
        _("parent address"), max_length=128, blank=True, default=""
    )
    is_subscriber_viewable = models.BooleanField(
        _("is subscriber viewable"), default=True
    )
    godfathers = models.ManyToManyField("User", related_name="godchildren", blank=True)

    objects = UserManager()

    USERNAME_FIELD = "username"
    # REQUIRED_FIELDS = ['email']

    def has_module_perms(self, package_name):
        return self.is_active

    def has_perm(self, perm, obj=None):
        return self.is_active and self.is_superuser

    def get_absolute_url(self):
        """
        This is needed for black magic powered UpdateView's children
        """
        return reverse("core:user_profile", kwargs={"user_id": self.pk})

    def __str__(self):
        return self.get_display_name()

    def to_dict(self):
        return self.__dict__

    @cached_property
    def was_subscribed(self):
        return self.subscriptions.exists()

    @cached_property
    def is_subscribed(self):
        s = self.subscriptions.filter(
            subscription_start__lte=timezone.now(), subscription_end__gte=timezone.now()
        )
        return s.exists()

    _club_memberships = {}
    _group_names = {}
    _group_ids = {}

    def is_in_group(self, group_name):
        """If the user is in the group passed in argument (as string or by id)"""
        group_id = 0
        g = None
        if isinstance(group_name, int):  # Handle the case where group_name is an ID
            if group_name in User._group_ids.keys():
                g = User._group_ids[group_name]
            else:
                g = Group.objects.filter(id=group_name).first()
                User._group_ids[group_name] = g
        else:
            if group_name in User._group_names.keys():
                g = User._group_names[group_name]
            else:
                g = Group.objects.filter(name=group_name).first()
                User._group_names[group_name] = g
        if g:
            group_name = g.name
            group_id = g.id
        else:
            return False
        if group_id == settings.SITH_GROUP_PUBLIC_ID:
            return True
        if group_id == settings.SITH_GROUP_SUBSCRIBERS_ID:
            return self.is_subscribed
        if group_id == settings.SITH_GROUP_OLD_SUBSCRIBERS_ID:
            return self.was_subscribed
        if (
            group_name == settings.SITH_MAIN_MEMBERS_GROUP
        ):  # We check the subscription if asked
            return self.is_subscribed
        if group_name[-len(settings.SITH_BOARD_SUFFIX) :] == settings.SITH_BOARD_SUFFIX:
            name = group_name[: -len(settings.SITH_BOARD_SUFFIX)]
            if name in User._club_memberships.keys():
                mem = User._club_memberships[name]
            else:
                from club.models import Club

                c = Club.objects.filter(unix_name=name).first()
                mem = c.get_membership_for(self)
                User._club_memberships[name] = mem
            if mem:
                return mem.role > settings.SITH_MAXIMUM_FREE_ROLE
            return False
        if (
            group_name[-len(settings.SITH_MEMBER_SUFFIX) :]
            == settings.SITH_MEMBER_SUFFIX
        ):
            name = group_name[: -len(settings.SITH_MEMBER_SUFFIX)]
            if name in User._club_memberships.keys():
                mem = User._club_memberships[name]
            else:
                from club.models import Club

                c = Club.objects.filter(unix_name=name).first()
                mem = c.get_membership_for(self)
                User._club_memberships[name] = mem
            if mem:
                return True
            return False
        if group_id == settings.SITH_GROUP_ROOT_ID and self.is_superuser:
            return True
        return group_name in self.cached_groups_names

    @cached_property
    def cached_groups_names(self):
        return [g.name for g in self.groups.all()]

    @cached_property
    def is_root(self):
        return (
            self.is_superuser
            or self.groups.filter(id=settings.SITH_GROUP_ROOT_ID).exists()
        )

    @cached_property
    def is_board_member(self):
        from club.models import Club

        return (
            Club.objects.filter(unix_name=settings.SITH_MAIN_CLUB["unix_name"])
            .first()
            .has_rights_in_club(self)
        )

    @cached_property
    def can_create_subscription(self):
        from club.models import Club

        for club in Club.objects.filter(
            id__in=settings.SITH_CAN_CREATE_SUBSCRIPTIONS
        ).all():
            if club.has_rights_in_club(self):
                return True
        return False

    @cached_property
    def is_launderette_manager(self):
        from club.models import Club

        return (
            Club.objects.filter(
                unix_name=settings.SITH_LAUNDERETTE_MANAGER["unix_name"]
            )
            .first()
            .get_membership_for(self)
        )

    @cached_property
    def is_banned_alcohol(self):
        return self.is_in_group(settings.SITH_GROUP_BANNED_ALCOHOL_ID)

    @cached_property
    def is_banned_counter(self):
        return self.is_in_group(settings.SITH_GROUP_BANNED_COUNTER_ID)

    def save(self, *args, **kwargs):
        create = False
        with transaction.atomic():
            if self.id:
                old = User.objects.filter(id=self.id).first()
                if old and old.username != self.username:
                    self._change_username(self.username)
            else:
                create = True
            super(User, self).save(*args, **kwargs)
            if (
                create and settings.IS_OLD_MYSQL_PRESENT
            ):  # Create user on the old site: TODO remove me!
                import MySQLdb

                try:
                    db = MySQLdb.connect(**settings.OLD_MYSQL_INFOS)
                    c = db.cursor()
                    c.execute(
                        """INSERT INTO utilisateurs (id_utilisateur, nom_utl, prenom_utl, email_utl, hash_utl, ae_utl) VALUES
                    (%s, %s, %s, %s, %s, %s)""",
                        (
                            self.id,
                            self.last_name,
                            self.first_name,
                            self.email,
                            "valid",
                            "0",
                        ),
                    )
                    db.commit()
                except Exception as e:
                    with open(settings.BASE_DIR + "/user_fail.log", "a") as f:
                        print(
                            "FAIL to add user %s (%s %s - %s) to old site"
                            % (self.id, self.first_name, self.last_name, self.email),
                            file=f,
                        )
                        print("Reason: %s" % (repr(e)), file=f)
                    db.rollback()

    def make_home(self):
        if self.home is None:
            home_root = SithFile.objects.filter(parent=None, name="users").first()
            if home_root is not None:
                home = SithFile(parent=home_root, name=self.username, owner=self)
                home.save()
                self.home = home
                self.save()

    def _change_username(self, new_name):
        u = User.objects.filter(username=new_name).first()
        if u is None:
            if self.home:
                self.home.name = new_name
                self.home.save()
        else:
            raise ValidationError(_("A user with that username already exists"))

    def get_profile(self):
        return {
            "last_name": self.last_name,
            "first_name": self.first_name,
            "nick_name": self.nick_name,
            "date_of_birth": self.date_of_birth,
        }

    def get_full_name(self):
        """
        Returns the first_name plus the last_name, with a space in between.
        """
        full_name = "%s %s" % (self.first_name, self.last_name)
        return full_name.strip()

    def get_short_name(self):
        "Returns the short name for the user."
        if self.nick_name:
            return self.nick_name
        return self.first_name + " " + self.last_name

    def get_display_name(self):
        """
        Returns the display name of the user.
        A nickname if possible, otherwise, the full name
        """
        if self.nick_name:
            return "%s (%s)" % (self.get_full_name(), self.nick_name)
        return self.get_full_name()

    def get_age(self):
        """
        Returns the age
        """
        today = timezone.now()
        born = self.date_of_birth
        return (
            today.year - born.year - ((today.month, today.day) < (born.month, born.day))
        )

    def email_user(self, subject, message, from_email=None, **kwargs):
        """
        Sends an email to this User.
        """
        if from_email is None:
            from_email = settings.DEFAULT_FROM_EMAIL
        send_mail(subject, message, from_email, [self.email], **kwargs)

    def generate_username(self):
        """
        Generates a unique username based on the first and last names.
        For example: Guy Carlier gives gcarlier, and gcarlier1 if the first one exists
        Returns the generated username
        """

        def remove_accents(data):
            return "".join(
                x
                for x in unicodedata.normalize("NFKD", data)
                if unicodedata.category(x)[0] == "L"
            ).lower()

        user_name = (
            remove_accents(self.first_name[0] + self.last_name)
            .encode("ascii", "ignore")
            .decode("utf-8")
        )
        un_set = [u.username for u in User.objects.all()]
        if user_name in un_set:
            i = 1
            while user_name + str(i) in un_set:
                i += 1
            user_name += str(i)
        self.username = user_name
        return user_name

    def is_owner(self, obj):
        """
        Determine if the object is owned by the user
        """
        if hasattr(obj, "is_owned_by") and obj.is_owned_by(self):
            return True
        if hasattr(obj, "owner_group") and self.is_in_group(obj.owner_group.name):
            return True
        if self.is_superuser or self.is_in_group(settings.SITH_GROUP_ROOT_ID):
            return True
        return False

    def can_edit(self, obj):
        """
        Determine if the object can be edited by the user
        """
        if hasattr(obj, "can_be_edited_by") and obj.can_be_edited_by(self):
            return True
        if hasattr(obj, "edit_groups"):
            for g in obj.edit_groups.all():
                if self.is_in_group(g.name):
                    return True
        if isinstance(obj, User) and obj == self:
            return True
        if self.is_owner(obj):
            return True
        return False

    def can_view(self, obj):
        """
        Determine if the object can be viewed by the user
        """
        if hasattr(obj, "can_be_viewed_by") and obj.can_be_viewed_by(self):
            return True
        if hasattr(obj, "view_groups"):
            for g in obj.view_groups.all():
                if self.is_in_group(g.name):
                    return True
        if self.can_edit(obj):
            return True
        return False

    def can_be_edited_by(self, user):
        return user.is_in_group(settings.SITH_MAIN_BOARD_GROUP) or user.is_root

    def can_be_viewed_by(self, user):
        return (user.was_subscribed and self.is_subscriber_viewable) or user.is_root

    def get_mini_item(self):
        return """
    <div class="mini_profile_link" >
    <span>
    <img src="%s" alt="%s" />
    </span>
    <em>%s</em>
    </a>
    """ % (
            self.profile_pict.get_download_url()
            if self.profile_pict
            else staticfiles_storage.url("core/img/unknown.jpg"),
            _("Profile"),
            escape(self.get_display_name()),
        )

    @cached_property
    def subscribed(self):
        return self.is_in_group(settings.SITH_MAIN_MEMBERS_GROUP)

    @cached_property
    def preferences(self):
        try:
            return self._preferences
        except:
            prefs = Preferences(user=self)
            prefs.save()
            return prefs

    @cached_property
    def forum_infos(self):
        try:
            return self._forum_infos
        except:
            from forum.models import ForumUserInfo

            infos = ForumUserInfo(user=self)
            infos.save()
            return infos

    @cached_property
    def clubs_with_rights(self):
        return [
            m.club.id
            for m in self.memberships.filter(
                models.Q(end_date__isnull=True) | models.Q(end_date__gte=timezone.now())
            ).all()
            if m.club.has_rights_in_club(self)
        ]

    @cached_property
    def is_com_admin(self):
        return self.is_in_group(settings.SITH_GROUP_COM_ADMIN_ID)


class AnonymousUser(AuthAnonymousUser):
    def __init__(self, request):
        super(AnonymousUser, self).__init__()

    @property
    def can_create_subscription(self):
        return False

    @property
    def was_subscribed(self):
        return False

    @property
    def is_subscribed(self):
        return False

    @property
    def subscribed(self):
        return False

    @property
    def is_root(self):
        return False

    @property
    def is_board_member(self):
        return False

    @property
    def is_launderette_manager(self):
        return False

    @property
    def is_banned_alcohol(self):
        return False

    @property
    def is_banned_counter(self):
        return False

    @property
    def forum_infos(self):
        raise PermissionDenied

    @property
    def favorite_topics(self):
        raise PermissionDenied

    def is_in_group(self, group_name):
        """
        The anonymous user is only the public group
        """
        group_id = 0
        if isinstance(group_name, int):  # Handle the case where group_name is an ID
            g = Group.objects.filter(id=group_name).first()
            if g:
                group_name = g.name
                group_id = g.id
            else:
                return False
        if group_id == settings.SITH_GROUP_PUBLIC_ID:
            return True
        return False

    def is_owner(self, obj):
        return False

    def can_edit(self, obj):
        return False

    def can_view(self, obj):
        if (
            hasattr(obj, "view_groups")
            and obj.view_groups.filter(id=settings.SITH_GROUP_PUBLIC_ID).exists()
        ):
            return True
        if hasattr(obj, "can_be_viewed_by") and obj.can_be_viewed_by(self):
            return True
        return False

    def get_display_name(self):
        return _("Visitor")


class Preferences(models.Model):
    user = models.OneToOneField(User, related_name="_preferences")
    receive_weekmail = models.BooleanField(
        _("do you want to receive the weekmail"), default=False
    )
    show_my_stats = models.BooleanField(_("show your stats to others"), default=False)
    notify_on_click = models.BooleanField(
        _("get a notification for every click"), default=False
    )
    notify_on_refill = models.BooleanField(
        _("get a notification for every refilling"), default=False
    )

    def get_display_name(self):
        return self.user.get_display_name()

    def get_absolute_url(self):
        return self.user.get_absolute_url()


def get_directory(instance, filename):
    return ".{0}/{1}".format(instance.get_parent_path(), filename)


def get_compressed_directory(instance, filename):
    return "./.compressed/{0}/{1}".format(instance.get_parent_path(), filename)


def get_thumbnail_directory(instance, filename):
    return "./.thumbnails/{0}/{1}".format(instance.get_parent_path(), filename)


class SithFile(models.Model):
    name = models.CharField(_("file name"), max_length=256, blank=False)
    parent = models.ForeignKey(
        "self", related_name="children", verbose_name=_("parent"), null=True, blank=True
    )
    file = models.FileField(
        upload_to=get_directory,
        verbose_name=_("file"),
        max_length=256,
        null=True,
        blank=True,
    )
    compressed = models.FileField(
        upload_to=get_compressed_directory,
        verbose_name=_("compressed file"),
        max_length=256,
        null=True,
        blank=True,
    )
    thumbnail = models.FileField(
        upload_to=get_thumbnail_directory,
        verbose_name=_("thumbnail"),
        max_length=256,
        null=True,
        blank=True,
    )
    owner = models.ForeignKey(User, related_name="owned_files", verbose_name=_("owner"))
    edit_groups = models.ManyToManyField(
        Group, related_name="editable_files", verbose_name=_("edit group"), blank=True
    )
    view_groups = models.ManyToManyField(
        Group, related_name="viewable_files", verbose_name=_("view group"), blank=True
    )
    is_folder = models.BooleanField(_("is folder"), default=True)
    mime_type = models.CharField(_("mime type"), max_length=30)
    size = models.IntegerField(_("size"), default=0)
    date = models.DateTimeField(_("date"), default=timezone.now)
    is_moderated = models.BooleanField(_("is moderated"), default=False)
    moderator = models.ForeignKey(
        User,
        related_name="moderated_files",
        verbose_name=_("owner"),
        null=True,
        blank=True,
    )
    asked_for_removal = models.BooleanField(_("asked for removal"), default=False)
    is_in_sas = models.BooleanField(
        _("is in the SAS"), default=False
    )  # Allows to query this flag, updated at each call to save()

    class Meta:
        verbose_name = _("file")

    def is_owned_by(self, user):
        if hasattr(self, "profile_of") and user.is_in_group(
            settings.SITH_MAIN_BOARD_GROUP
        ):
            return True
        if user.is_in_group(settings.SITH_GROUP_COM_ADMIN_ID):
            return True
        if self.is_in_sas and user.is_in_group(settings.SITH_GROUP_SAS_ADMIN_ID):
            return True
        return user.id == self.owner.id

    def can_be_viewed_by(self, user):
        if hasattr(self, "profile_of"):
            return user.can_view(self.profile_of)
        if hasattr(self, "avatar_of"):
            return user.can_view(self.avatar_of)
        if hasattr(self, "scrub_of"):
            return user.can_view(self.scrub_of)
        return False

    def delete(self):
        for c in self.children.all():
            c.delete()
        self.file.delete()
        if self.compressed:
            self.compressed.delete()
        if self.thumbnail:
            self.thumbnail.delete()
        return super(SithFile, self).delete()

    def clean(self):
        """
        Cleans up the file
        """
        super(SithFile, self).clean()
        if "/" in self.name:
            raise ValidationError(_("Character '/' not authorized in name"))
        if self == self.parent:
            raise ValidationError(_("Loop in folder tree"), code="loop")
        if self == self.parent or (
            self.parent is not None and self in self.get_parent_list()
        ):
            raise ValidationError(_("Loop in folder tree"), code="loop")
        if self.parent and self.parent.is_file:
            raise ValidationError(
                _("You can not make a file be a children of a non folder file")
            )
        if (
            self.parent is None
            and SithFile.objects.exclude(id=self.id)
            .filter(parent=None, name=self.name)
            .exists()
        ) or (
            self.parent
            and self.parent.children.exclude(id=self.id).filter(name=self.name).exists()
        ):
            raise ValidationError(_("Duplicate file"), code="duplicate")
        if self.is_folder:
            if self.file:
                try:
                    import imghdr

                    if imghdr.what(None, self.file.read()) not in [
                        "gif",
                        "png",
                        "jpeg",
                    ]:
                        self.file.delete()
                        self.file = None
                except:
                    self.file = None
            self.mime_type = "inode/directory"
        if self.is_file and (self.file is None or self.file == ""):
            raise ValidationError(_("You must provide a file"))

    def save(self, *args, **kwargs):
        sas = SithFile.objects.filter(id=settings.SITH_SAS_ROOT_DIR_ID).first()
        self.is_in_sas = sas in self.get_parent_list()
        copy_rights = False
        if self.id is None:
            copy_rights = True
        super(SithFile, self).save(*args, **kwargs)
        if copy_rights:
            self.copy_rights()
        if self.is_in_sas:
            for u in (
                RealGroup.objects.filter(id=settings.SITH_GROUP_SAS_ADMIN_ID)
                .first()
                .users.all()
            ):
                Notification(
                    user=u,
                    url=reverse("sas:moderation"),
                    type="SAS_MODERATION",
                    param="1",
                ).save()

    def apply_rights_recursively(self, only_folders=False):
        children = self.children.all()
        if only_folders:
            children = children.filter(is_folder=True)
        for c in children:
            c.copy_rights()
            c.apply_rights_recursively(only_folders)

    def copy_rights(self):
        """Copy, if possible, the rights of the parent folder"""
        if self.parent is not None:
            self.edit_groups = self.parent.edit_groups.all()
            self.view_groups = self.parent.view_groups.all()
            self.save()

    def move_to(self, parent):
        """
        Move a file to a new parent.
        `parent` must be a SithFile with the `is_folder=True` property. Otherwise, this function doesn't change
        anything.
        This is done only at the DB level, so that it's very fast for the user. Indeed, this function doesn't modify
        SithFiles recursively, so it stays efficient even with top-level folders.
        """
        if not parent.is_folder:
            return
        self.parent = parent
        self.clean()
        self.save()

    def _repair_fs(self):
        """
        This function rebuilds recursively the filesystem as it should be
        regarding the DB tree.
        """
        if self.is_folder:
            for c in self.children.all():
                c._repair_fs()
            return
        elif not self._check_path_consistence():
            # First get future parent path and the old file name
            # Prepend "." so that we match all relative handling of Django's
            # file storage
            parent_path = "." + self.parent.get_full_path()
            parent_full_path = settings.MEDIA_ROOT + parent_path
            print("Parent full path: %s" % parent_full_path)
            os.makedirs(parent_full_path, exist_ok=True)
            old_path = self.file.name  # Should be relative: "./users/skia/bleh.jpg"
            new_path = "." + self.get_full_path()
            print("Old path: %s " % old_path)
            print("New path: %s " % new_path)
            try:
                # Make this atomic, so that a FS problem rolls back the DB change
                with transaction.atomic():
                    # Set the new filesystem path
                    self.file.name = new_path
                    self.save()
                    print("New file path: %s " % self.file.path)
                    # Really move at the FS level
                    if os.path.exists(parent_full_path):
                        os.rename(
                            settings.MEDIA_ROOT + old_path,
                            settings.MEDIA_ROOT + new_path,
                        )
                        # Empty directories may remain, but that's not really a
                        # problem, and that can be solved with a simple shell
                        # command: `find . -type d -empty -delete`
            except Exception as e:
                print("This file likely had a problem. Here is the exception:")
                print(repr(e))
            print("-" * 80)

    def _check_path_consistence(self):
        file_path = str(self.file)
        file_full_path = settings.MEDIA_ROOT + file_path
        db_path = ".%s" % self.get_full_path()
        if not os.path.exists(file_full_path):
            print("%s: WARNING: real file does not exists!" % self.id)
            print("file path: %s" % file_path, end="")
            print("  db path: %s" % db_path)
            return False
        if file_path != db_path:
            print("%s: " % self.id, end="")
            print("file path: %s" % file_path, end="")
            print("  db path: %s" % db_path)
            return False
        print("%s OK (%s)" % (self.id, file_path))
        return True

    def _check_fs(self):
        if self.is_folder:
            for c in self.children.all():
                c._check_fs()
            return
        else:
            self._check_path_consistence()

    def __getattribute__(self, attr):
        if attr == "is_file":
            return not self.is_folder
        else:
            return super(SithFile, self).__getattribute__(attr)

    @cached_property
    def as_picture(self):
        from sas.models import Picture

        return Picture.objects.filter(id=self.id).first()

    @cached_property
    def as_album(self):
        from sas.models import Album

        return Album.objects.filter(id=self.id).first()

    def __str__(self):
        if self.is_folder:
            return _("Folder: ") + self.name
        else:
            return _("File: ") + self.name

    def get_parent_list(self):
        l = []
        p = self.parent
        while p is not None:
            l.append(p)
            p = p.parent
        return l

    def get_parent_path(self):
        return "/" + "/".join([p.name for p in self.get_parent_list()[::-1]])

    def get_full_path(self):
        return self.get_parent_path() + "/" + self.name

    def get_display_name(self):
        return self.name

    def get_download_url(self):
        return reverse("core:download", kwargs={"file_id": self.id})

    def __str__(self):
        return self.get_parent_path() + "/" + self.name


class LockError(Exception):
    """There was a lock error on the object"""

    pass


class AlreadyLocked(LockError):
    """The object is already locked"""

    pass


class NotLocked(LockError):
    """The object is not locked"""

    pass


class Page(models.Model):
    """
    The page class to build a Wiki
    Each page may have a parent and it's URL is of the form my.site/page/<grd_pa>/<parent>/<mypage>
    It has an ID field, but don't use it, since it's only there for DB part, and because compound primary key is
    awkward!
    Prefere querying pages with Page.get_page_by_full_name()