"""various library content hooks

:organization: Logilab

:copyright: 2001-2009 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.

:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr

:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses

"""

__docformat__ = "restructuredtext en"

from datetime import datetime

from cubicweb import RepositoryError

from cubicweb.common.uilib import soup2xhtml

from cubicweb.server.hooksmanager import Hook

from cubicweb.server.pool import PreCommitOperation

class SetModificationDateOnStateChange(Hook):

    """update entity's modification date after changing its state"""

    events = ('after_add_relation',)

    accepts = ('in_state',)

    def call(self, session, fromeid, rtype, toeid):

        if fromeid in session.transaction_data.get('neweids', ()):

            # new entity, not needed

            return

        entity = session.entity_from_eid(fromeid)

        try:

            entity.set_attributes(modification_date=datetime.now())

        except RepositoryError, ex:

            # usually occurs if entity is coming from a read-only source

            # (eg ldap user)

            self.warning('cant change modification date for %s: %s', entity, ex)

class AddUpdateCWUserHook(Hook):

    """ensure user logins are stripped"""

    events = ('before_add_entity', 'before_update_entity',)

    accepts = ('CWUser',)

    def call(self, session, entity):

        if 'login' in entity and entity['login']:

            entity['login'] = entity['login'].strip()

class AutoDeleteBookmark(PreCommitOperation):

    beid = None # make pylint happy

    def precommit_event(self):

        session = self.session

        if not self.beid in session.transaction_data.get('pendingeids', ()):

            if not session.unsafe_execute('Any X WHERE X bookmarked_by U, X eid %(x)s',

                                          {'x': self.beid}, 'x'):

                session.unsafe_execute('DELETE Bookmark X WHERE X eid %(x)s',

                                       {'x': self.beid}, 'x')

class DelBookmarkedByHook(Hook):

    """ensure user logins are stripped"""

    events = ('after_delete_relation',)

    accepts = ('bookmarked_by',)

    def call(self, session, subj, rtype, obj):

        AutoDeleteBookmark(session, beid=subj)

class TidyHtmlFields(Hook):

    """tidy HTML in rich text strings"""

    events = ('before_add_entity', 'before_update_entity')

    accepts = ('Any',)

    def call(self, session, entity):

        metaattrs = entity.e_schema.meta_attributes()

        for metaattr, (metadata, attr) in metaattrs.iteritems():

            if metadata == 'format':

                try:

                    value = entity[attr]

                except KeyError:

                    continue # no text to tidy

                if isinstance(value, unicode): # filter out None and Binary

                    if self.event == 'before_add_entity':

                        fmt = entity.get(metaattr)

                    else:

                        fmt = entity.get_value(metaattr)

                    if fmt == 'text/html':

                        entity[attr] = soup2xhtml(value, session.encoding)