#
# Thierry Parmentelat - INRIA
#
from PLC.Faults import *
from PLC.Method import Method
from PLC.Parameter import Parameter, Mixed
from PLC.Auth import Auth

from PLC.Persons import Person, Persons
from PLC.TagTypes import TagType, TagTypes
from PLC.PersonTags import PersonTag, PersonTags

# need to import so the core classes get decorated with caller_may_write_tag
from PLC.AuthorizeHelpers import AuthorizeHelpers

class AddPersonTag(Method):
    """
    Sets the specified setting for the specified person
    to the specified value.

    Admins have full access.  Non-admins can change their own tags.

    Returns the new person_tag_id (> 0) if successful, faults
    otherwise.
    """

    roles = ['admin', 'pi', 'tech', 'user']

    accepts = [
        Auth(),
        # no other way to refer to a person
        PersonTag.fields['person_id'],
        Mixed(TagType.fields['tag_type_id'],
              TagType.fields['tagname']),
        PersonTag.fields['value'],
        ]

    returns = Parameter(int, 'New person_tag_id (> 0) if successful')

    def call(self, auth, person_id, tag_type_id_or_name, value):
        persons = Persons(self.api, [person_id])
        if not persons:
            raise PLCInvalidArgument, "No such person %r"%person_id
        person = persons[0]

        tag_types = TagTypes(self.api, [tag_type_id_or_name])
        if not tag_types:
            raise PLCInvalidArgument, "No such tag type %r"%tag_type_id_or_name
        tag_type = tag_types[0]

        # checks for existence - does not allow several different settings
        conflicts = PersonTags(self.api, {'person_id':person['person_id'],
                                          'tag_type_id':tag_type['tag_type_id']})

        if len(conflicts) :
            raise PLCInvalidArgument, "Person %d (%s) already has setting %d"% \
                (person['person_id'],person['email'], tag_type['tag_type_id'])

        # check authorizations
        person.caller_may_write_tag (self.api,self.caller,tag_type)

        person_tag = PersonTag(self.api)
        person_tag['person_id'] = person['person_id']
        person_tag['tag_type_id'] = tag_type['tag_type_id']
        person_tag['value'] = value

        person_tag.sync()
        self.object_ids = [person_tag['person_tag_id']]

        return person_tag['person_tag_id']