# Authors:
#   Rob Crittenden <rcritten@redhat.com>
#   Martin Kosek <mkosek@redhat.com>
#
# Copyright (C) 2010  Red Hat
# see file 'COPYING' for use and warranty information
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as 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, see <http://www.gnu.org/licenses/>.

from ipalib import api, _, ngettext
from ipalib import Flag, Str
from ipalib.request import context
from ipalib import api, crud, errors
from ipalib import output
from ipalib import Object, Command
from ipalib.plugable import Registry
from ipalib.plugins.baseldap import gen_pkey_only_option, pkey_to_value

__doc__ = _("""
Group to Group Delegation

A permission enables fine-grained delegation of permissions. Access Control
Rules, or instructions (ACIs), grant permission to permissions to perform
given tasks such as adding a user, modifying a group, etc.

Group to Group Delegations grants the members of one group to update a set
of attributes of members of another group.

EXAMPLES:

 Add a delegation rule to allow managers to edit employee's addresses:
   ipa delegation-add --attrs=street --group=managers --membergroup=employees "managers edit employees' street"

 When managing the list of attributes you need to include all attributes
 in the list, including existing ones. Add postalCode to the list:
   ipa delegation-mod --attrs=street --attrs=postalCode --group=managers --membergroup=employees "managers edit employees' street"

 Display our updated rule:
   ipa delegation-show "managers edit employees' street"

 Delete a rule:
   ipa delegation-del "managers edit employees' street"
""")

register = Registry()

ACI_PREFIX=u"delegation"

output_params = (
    Str('aci',
        label=_('ACI'),
    ),
)

@register()
class delegation(Object):
    """
    Delegation object.
    """

    bindable = False
    object_name = _('delegation')
    object_name_plural = _('delegations')
    label = _('Delegations')
    label_singular = _('Delegation')

    takes_params = (
        Str('aciname',
            cli_name='name',
            label=_('Delegation name'),
            doc=_('Delegation name'),
            primary_key=True,
        ),
        Str('permissions*',
            cli_name='permissions',
            label=_('Permissions'),
            doc=_('Permissions to grant (read, write). Default is write.'),
            csv=True,
        ),
        Str('attrs+',
            cli_name='attrs',
            label=_('Attributes'),
            doc=_('Attributes to which the delegation applies'),
            csv=True,
            normalizer=lambda value: value.lower(),
        ),
        Str('memberof',
            cli_name='membergroup',
            label=_('Member user group'),
            doc=_('User group to apply delegation to'),
        ),
        Str('group',
            cli_name='group',
            label=_('User group'),
            doc=_('User group ACI grants access to'),
        ),
    )

    def __json__(self):
        json_friendly_attributes = (
            'label', 'label_singular', 'takes_params', 'bindable', 'name',
            'object_name', 'object_name_plural',
        )
        json_dict = dict(
            (a, getattr(self, a)) for a in json_friendly_attributes
        )
        json_dict['primary_key'] = self.primary_key.name

        json_dict['methods'] = [m for m in self.methods]
        return json_dict

    def postprocess_result(self, result):
        try:
            # do not include prefix in result
            del result['aciprefix']
        except KeyError:
            pass



@register()
class delegation_add(crud.Create):
    __doc__ = _('Add a new delegation.')

    msg_summary = _('Added delegation "%(value)s"')
    has_output_params = output_params

    def execute(self, aciname, **kw):
        if not 'permissions' in kw:
            kw['permissions'] = (u'write',)
        kw['aciprefix'] = ACI_PREFIX
        result = api.Command['aci_add'](aciname, **kw)['result']
        self.obj.postprocess_result(result)

        return dict(
            result=result,
            value=pkey_to_value(aciname, kw),
        )



@register()
class delegation_del(crud.Delete):
    __doc__ = _('Delete a delegation.')

    has_output = output.standard_boolean
    msg_summary = _('Deleted delegation "%(value)s"')

    def execute(self, aciname, **kw):
        kw['aciprefix'] = ACI_PREFIX
        result = api.Command['aci_del'](aciname, **kw)
        self.obj.postprocess_result(result)
        return dict(
            result=True,
            value=pkey_to_value(aciname, kw),
        )



@register()
class delegation_mod(crud.Update):
    __doc__ = _('Modify a delegation.')

    msg_summary = _('Modified delegation "%(value)s"')
    has_output_params = output_params

    def execute(self, aciname, **kw):
        kw['aciprefix'] = ACI_PREFIX
        result = api.Command['aci_mod'](aciname, **kw)['result']
        self.obj.postprocess_result(result)

        return dict(
            result=result,
            value=pkey_to_value(aciname, kw),
        )



@register()
class delegation_find(crud.Search):
    __doc__ = _('Search for delegations.')

    msg_summary = ngettext(
        '%(count)d delegation matched', '%(count)d delegations matched', 0
    )

    takes_options = (gen_pkey_only_option("name"),)
    has_output_params = output_params

    def execute(self, term, **kw):
        kw['aciprefix'] = ACI_PREFIX
        results = api.Command['aci_find'](term, **kw)['result']

        for aci in results:
            self.obj.postprocess_result(aci)

        return dict(
            result=results,
            count=len(results),
            truncated=False,
        )



@register()
class delegation_show(crud.Retrieve):
    __doc__ = _('Display information about a delegation.')

    has_output_params = output_params

    def execute(self, aciname, **kw):
        result = api.Command['aci_show'](aciname, aciprefix=ACI_PREFIX, **kw)['result']
        self.obj.postprocess_result(result)
        return dict(
            result=result,
            value=pkey_to_value(aciname, kw),
        )