#
# Functions for interacting with the network_methods table in the database
#
#
from types import StringTypes
from PLC.Faults import *
from PLC.Parameter import Parameter
from PLC.Storage.AlchemyObject import AlchemyObj

class NetworkMethod(AlchemyObj):
    """
    Representation of a row in the network_methods table. To use,
    instantiate with a dict of values.
    """

    tablename = 'network_methods'
    join_tables = ['interfaces']
    fields = {
        'method': Parameter(str, "Network method", max = 20, primary_key=True),
        }

    def validate_method(self, name):
        # Make sure name is not blank
        if not len(name):
            raise PLCInvalidArgument, "Network method must be specified"

        # Make sure network method does not alredy exist
        conflicts = NetworkMethods(self.api, name)
        if conflicts:
            raise PLCInvalidArgument, "Network method name already in use"

        return name

    def sync(self, commit = True, validate=True):
        AlchemyObj.sync(self, commit, validate)
        AlchemyObj.insert(self, dict(self))

    def delete(self, commit=True):
        assert 'method' in self
        AlchemyObj.delete(self, dict(self))
        

class NetworkMethods(list):
    """
    Representation of the network_methods table in the database.
    """

    def __init__(self, api, methods = None):

        if not methods:
            network_methods = NetworkMethod().select()
        elif isinstance(methods, StringTypes):
            network_methods = NetworkMethod().select(filter={'method': methods})
        else:
            raise PLCInvalidArgument, "Wrong network method filter %r"%methods

        self.extend(network_methods)