# Authors:
#   Jason Gerard DeRose <jderose@redhat.com>
#   Rob Crittenden <rcritten@redhat.com>
#
# Copyright (C) 2008  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; version 2 only
#
# 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 Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

"""
Frontend plugins for service (Identity).
"""

from ipalib import frontend
from ipalib import crud
from ipalib.frontend import Param
from ipalib import api
from ipalib import errors
from ipalib import ipa_types

class service(frontend.Object):
    """
    Service object.
    """
    takes_params = (
        Param('principal', primary_key=True),
    )
api.register(service)


class service_add(crud.Add):
    'Add a new service.'
    takes_options = (
        Param('force?', type=ipa_types.Bool(), default=False, doc='Force a service principal name'),
    )
    def execute(self, principal, **kw):
        """
        Execute the service-add operation.

        The dn should not be passed as a keyword argument as it is constructed
        by this method.

        Returns the entry as it will be created in LDAP.

        :param principal: The service to be added in the form: service/hostname
        :param kw: Keyword arguments for the other LDAP attributes.
        """
        assert 'krbprincipalname' not in kw
        ldap = self.api.Backend.ldap

        force = kw.get('force', False)
        try:
            del kw['force']
        except:
            pass

        # Break down the principal into its component parts, which may or
        # may not include the realm.
        sp = principal.split('/')
        if len(sp) != 2:
            raise errors.MalformedServicePrincipal
        service = sp[0]

        sr = sp[1].split('@')
        if len(sr) == 1:
            hostname = sr[0].lower()
            realm = self.api.env.realm
        elif len(sr) == 2:
            hostname = sr[0].lower()
            realm = sr[1]
        else:
            raise MalformedServicePrincipal

        """
        FIXME once DNS client is done
        if not force:
            fqdn = hostname + "."
            rs = dnsclient.query(fqdn, dnsclient.DNS_C_IN, dnsclient.DNS_T_A)
            if len(rs) == 0:
                logging.debug("IPA: DNS A record lookup failed for '%s'" % hostname)
                raise ipaerror.gen_exception(ipaerror.INPUT_NOT_DNS_A_RECORD)
            else:
                logging.debug("IPA: found %d records for '%s'" % (len(rs), hostname))
        """

        # At some point we'll support multiple realms
        if (realm != self.api.env.realm):
            raise errors.RealmMismatch

        # Put the principal back together again
        princ_name = service + "/" + hostname + "@" + realm

        dn = ldap.make_service_dn(princ_name)

        kw['dn'] = dn
        kw['objectClass'] = ['krbPrincipal', 'krbPrincipalAux', 'krbTicketPolicyAux']

        return ldap.create(**kw)

    def output_to_cli(self, ret):
        if ret:
            print "Service added" 

api.register(service_add)


class service_del(crud.Del):
    'Delete an existing service.'
    def execute(self, principal, **kw):
        """
        Delete a service principal.

        principal is the krbprincipalname of the entry to delete.

        This should be called with much care.

        :param principal: The service to be added in the form: service/hostname
        :param kw: not used
        """
        ldap = self.api.Backend.ldap
        dn = ldap.find_entry_dn("krbprincipalname", principal)
        return ldap.delete(dn)

    def output_to_cli(self, ret):
        if ret:
            print "Service removed"

api.register(service_del)

# There is no service-mod. The principal itself contains nothing that
# is user-changeable

class service_find(crud.Find):
    'Search the existing services.'
    def execute(self, principal, **kw):
        ldap = self.api.Backend.ldap

        kw['filter'] = "&(objectclass=krbPrincipalAux)(!(objectClass=person))(!(|(krbprincipalname=kadmin/*)(krbprincipalname=K/M@*)(krbprincipalname=krbtgt/*)))"
        kw['krbprincipalname'] = principal

        object_type = ldap.get_object_type("krbprincipalname")
        if object_type and not kw.get('objectclass'):
            kw['objectclass'] = object_type

        return ldap.search(**kw)

    def output_for_cli(self, services):
        if not services:
            return

        counter = services[0]
        services = services[1:]
        if counter == 0:
            print "No entries found"
            return
        elif counter == -1:
            print "These results are truncated."
            print "Please refine your search and try again."

        for s in services:
            for a in s.keys():
                print "%s: %s" % (a, s[a])

api.register(service_find)


class service_show(crud.Get):
    'Examine an existing service.'
    def execute(self, principal, **kw):
        """
        Execute the service-show operation.

        The dn should not be passed as a keyword argument as it is constructed
        by this method.

        Returns the entry

        :param principal: The service principal to retrieve
        :param kw: Not used.
        """
        ldap = self.api.Backend.ldap
        dn = ldap.find_entry_dn("krbprincipalname", principal)
        # FIXME: should kw contain the list of attributes to display?
        return ldap.retrieve(dn)

api.register(service_show)