)

class RepoGroup(Base, BaseDbModel):

    __tablename__ = 'groups'

    __table_args__ = (

        _table_args_default_dict,

    )

    SEP = ' » '

    group_id = Column(Integer(), primary_key=True)

    group_name = Column(Unicode(255), nullable=False, unique=True) # full path

    parent_group_id = Column('group_parent_id', Integer(), ForeignKey('groups.group_id'), nullable=True)

    group_description = Column(Unicode(10000), nullable=False)

    owner_id = Column('user_id', Integer(), ForeignKey('users.user_id'), nullable=False)

    created_on = Column(DateTime(timezone=False), nullable=False, default=datetime.datetime.now)

    repo_group_to_perm = relationship('UserRepoGroupToPerm', cascade='all', order_by='UserRepoGroupToPerm.group_to_perm_id')

    users_group_to_perm = relationship('UserGroupRepoGroupToPerm', cascade='all')

    parent_group = relationship('RepoGroup', remote_side=group_id)

    owner = relationship('User')

    @classmethod

    def query(cls, sorted=False):

        """Add RepoGroup-specific helpers for common query constructs.

        sorted: if True, apply the default ordering (name, case insensitive).

        """

        q = super(RepoGroup, cls).query()

        if sorted:

            q = q.order_by(sqlalchemy.func.lower(RepoGroup.group_name))

        return q

    def __init__(self, group_name='', parent_group=None):

        self.group_name = group_name

        self.parent_group = parent_group

    def __repr__(self):

        return "<%s %s: %s>" % (self.__class__.__name__,

                                self.group_id, self.group_name)

    @classmethod

    def _generate_choice(cls, repo_group):

        """Return tuple with group_id and name as html literal"""

        from webhelpers2.html import literal

        if repo_group is None:

            return (-1, '-- %s --' % _('top level'))

    @classmethod

    def groups_choices(cls, groups):

        """Return tuples with group_id and name as html literal."""

        return sorted((cls._generate_choice(g) for g in groups),

                      key=lambda c: c[1].split(cls.SEP))

    @classmethod

    def guess_instance(cls, value):

        return super(RepoGroup, cls).guess_instance(value, RepoGroup.get_by_group_name)

    @classmethod

    def get_by_group_name(cls, group_name, case_insensitive=False):

        group_name = group_name.rstrip('/')

        if case_insensitive:

            gr = cls.query() \

                .filter(sqlalchemy.func.lower(cls.group_name) == sqlalchemy.func.lower(group_name))

        else:

            gr = cls.query() \

                .filter(cls.group_name == group_name)

        return gr.scalar()

    @property

    def parents(self):

        groups = []

        group = self.parent_group

        while group is not None:

            groups.append(group)

            group = group.parent_group

            assert group not in groups, group # avoid recursion on bad db content

        groups.reverse()

        return groups

    @property

    def children(self):

        return RepoGroup.query().filter(RepoGroup.parent_group == self)

    @property

    def name(self):

        return self.group_name.split(URL_SEP)[-1]

    @property

    def full_path(self):

        return self.group_name

    @property

    def full_path_splitted(self):

        return self.group_name.split(URL_SEP)