#
# 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.Sites import Site, Sites
from PLC.Nodes import Nodes
from PLC.TagTypes import TagType, TagTypes
from PLC.SiteTags import SiteTag, SiteTags

class UpdateSiteTag(Method):
    """
    Updates the value of an existing site setting

    Admins have full access.  Non-admins need to 
    (1) have at least one of the roles attached to the tagtype, 
    and (2) belong in the same site as the tagged subject.

    Returns 1 if successful, faults otherwise.
    """

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

    accepts = [
        Auth(),
        SiteTag.fields['site_tag_id'],
        SiteTag.fields['value']
        ]

    returns = Parameter(int, '1 if successful')

    def call(self, auth, site_tag_id, value):
        site_tags = SiteTags(self.api, [site_tag_id])
        if not site_tags:
            raise PLCInvalidArgument, "No such site setting %r"%site_tag_id
        site_tag = site_tags[0]

        tag_type_id = site_tag['tag_type_id']
        tag_type = TagTypes (self.api,[tag_type_id])[0]

        sites = Sites (self.api, site_tag['site_id'])
        if not sites:
            raise PLCInvalidArgument, "No such site %d"%site_tag['site_id']
        site=sites[0]
        
        # check authorizations
        site.caller_may_write_tag(self.api,self.caller,tag_type)
            
        site_tag['value'] = value
        site_tag.sync()

        self.object_ids = [site_tag['site_tag_id']]
        return 1