# copyright 2003-2011 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

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

#

# This file is part of CubicWeb.

#

# CubicWeb is free software: you can redistribute it and/or modify it under the

# terms of the GNU Lesser General Public License as published by the Free

# Software Foundation, either version 2.1 of the License, or (at your option)

# any later version.

#

# CubicWeb 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 Lesser General Public License for more

# details.

#

# You should have received a copy of the GNU Lesser General Public License along

# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.

"""base application's entities class implementation: `AnyEntity`"""

__docformat__ = "restructuredtext en"

from warnings import warn

from logilab.common.deprecation import deprecated

from logilab.common.decorators import cached

from cubicweb import Unauthorized, typed_eid

from cubicweb.entity import Entity

class AnyEntity(Entity):

    """an entity instance has e_schema automagically set on the class and

    instances have access to their issuing cursor

    """

    __regid__ = 'Any'

    __implements__ = ()

    @classmethod

    def cw_create_url(cls, req, **kwargs):

        """ return the url of the entity creation form for this entity type"""

        return req.build_url('add/%s' % cls.__regid__, **kwargs)

    # meta data api ###########################################################

    def dc_title(self):

        """return a suitable *unicode* title for this entity"""

        for rschema, attrschema in self.e_schema.attribute_definitions():

            if rschema.meta:

                continue

            value = self.cw_attr_value(rschema.type)

            if value:

                # make the value printable (dates, floats, bytes, etc.)

                return self.printable_value(rschema.type, value, attrschema.type,

                                            format='text/plain')

        return u'%s #%s' % (self.dc_type(), self.eid)

    def dc_long_title(self):

        """return a more detailled title for this entity"""

        return self.dc_title()

    def dc_description(self, format='text/plain'):

        """return a suitable description for this entity"""

        if 'description' in self.e_schema.subjrels:

            return self.printable_value('description', format=format)

        return u''

    def dc_authors(self):

        """return a suitable description for the author(s) of the entity"""

        try:

            return ', '.join(u.name() for u in self.owned_by)

        except Unauthorized:

            return u''

    def dc_creator(self):

        """return a suitable description for the creator of the entity"""

        if self.creator:

            return self.creator.name()

        return u''

    def dc_date(self, date_format=None):# XXX default to ISO 8601 ?

        """return latest modification date of this entity"""

        return self._cw.format_date(self.modification_date, date_format=date_format)

    def dc_type(self, form=''):

        """return the display name for the type of this entity (translated)"""

        return self.e_schema.display_name(self._cw, form)

    def dc_language(self):

        """return language used by this entity (translated)"""

        # check if entities has internationalizable attributes

        # XXX one is enough or check if all String attributes are internationalizable?

        for rschema, attrschema in self.e_schema.attribute_definitions():

            if rschema.rdef(self.e_schema, attrschema).internationalizable:

                return self._cw._(self._cw.user.property_value('ui.language'))

        return self._cw._(self._cw.vreg.property_value('ui.language'))

    @property

    def creator(self):

        """return the CWUser entity which has created this entity, or None if

        unknown or if the curent user doesn't has access to this euser

        """

        try:

            return self.created_by[0]

        except (Unauthorized, IndexError):

            return None

    # abstractions making the whole things (well, some at least) working ######

    def sortvalue(self, rtype=None):

        """return a value which can be used to sort this entity or given

        entity's attribute

        """

        if rtype is None:

            return self.dc_title().lower()

        value = self.cw_attr_value(rtype)

        # do not restrict to `unicode` because Bytes will return a `str` value

        if isinstance(value, basestring):

            return self.printable_value(rtype, format='text/plain').lower()

        return value

    # edition helper functions ################################################

    def linked_to(self, rtype, role, remove=True):

        """if entity should be linked to another using '__linkto' form param for

        the given relation/role, return eids of related entities

        This method is consuming matching link-to information from form params

        if `remove` is True (by default). Computed values are stored into a

        `cw_linkto` attribute, a dictionary with (relation, role) as key and

        linked eids as value.

        """

        try:

            return self.cw_linkto[(rtype, role)]

        except AttributeError:

            self.cw_linkto = {}

        except KeyError:

            pass

        linktos = list(self._cw.list_form_param('__linkto'))

        linkedto = []

        for linkto in linktos[:]:

            ltrtype, eid, ltrole = linkto.split(':')

            if rtype == ltrtype and role == ltrole:

                # delete __linkto from form param to avoid it being added as

                # hidden input

                if remove:

                    linktos.remove(linkto)

                    self._cw.form['__linkto'] = linktos

                linkedto.append(typed_eid(eid))

        self.cw_linkto[(rtype, role)] = linkedto

        return linkedto

    # server side helpers #####################################################

# XXX:  store a reference to the AnyEntity class since it is hijacked in goa

#       configuration and we need the actual reference to avoid infinite loops

#       in mro

ANYENTITY = AnyEntity

def fetch_config(fetchattrs, mainattr=None, pclass=AnyEntity, order='ASC'):

    if pclass is ANYENTITY:

        pclass = AnyEntity # AnyEntity and ANYENTITY may be different classes

    if pclass is not None:

        fetchattrs += pclass.fetch_attrs

    if mainattr is None:

        mainattr = fetchattrs[0]

    @classmethod

    def fetch_order(cls, attr, var):

        if attr == mainattr:

            return '%s %s' % (var, order)

        return None

    return fetchattrs, fetch_order