'''
/*
 * Copyright 2010-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */
 '''

import AWSIoTCommand
from core.exception.AWSIoTExceptions import subscribeError
from core.exception.AWSIoTExceptions import subscribeTimeoutException


class commandShadowRegisterDeltaCallback(AWSIoTCommand.AWSIoTCommand):
    # Target API: deviceShadow.shadowRegisterDeltaCallback(srcCallback)
    # Parameters: deviceShadowName, sketchSubscribeSlot, callback

    def __init__(self, srcParameterList, srcSerialCommuteServer, srcShadowRegistrationTable, srcShadowSubscribeRecord):
        self._commandProtocolName = "s_rd"
        self._parameterList = srcParameterList
        self._serialCommServerHandler = srcSerialCommuteServer
        # To get the corresponding registered deviceShadow instance
        self._shadowRegistrationTable = srcShadowRegistrationTable
        # To get update the sketch slot information
        self._shadowSubscribeRecord = srcShadowSubscribeRecord
        self._desiredNumberOfParameters = 3

    def _validateCommand(self):
        isNumberOfParameterMatched = AWSIoTCommand.AWSIoTCommand._validateCommand(self)
        isDataStructureExist = self._shadowRegistrationTable is not None and self._serialCommServerHandler is not None
        isDeviceShadowNameRegistered = False
        if isNumberOfParameterMatched and isDataStructureExist:
            isDeviceShadowNameRegistered = self._shadowRegistrationTable.get(self._parameterList[0]) is not None
        return isNumberOfParameterMatched and isDataStructureExist and isDeviceShadowNameRegistered

    def execute(self):
        returnMessage = "S_RD T"
        if not self._validateCommand():
            returnMessage = "S_RD1F: " + "No shadow init."
        else:
            try:
                currentDeviceShadow = self._shadowRegistrationTable.get(self._parameterList[0])  # By this time, currentDeviceShadow should never be None
                # Real shadow register delta callback
                currentDeviceShadow.shadowRegisterDeltaCallback(self._parameterList[2])
                # Update sketch subscribe slot number, using deviceShadow name
                self._shadowSubscribeRecord[self._parameterList[0]] = int(self._parameterList[1])
            except TypeError as e:
                returnMessage = "S_RD2F: " + str(e.message)
            # One subscription
            except subscribeError as e:
                returnMessage = "S_RD3F: " + str(e.message)
            except subscribeTimeoutException as e:
                returnMessage = "S_RD4F: " + str(e.message)
            except Exception as e:
                returnMessage = "S_RDFF: " + "Unknown error."
        self._serialCommServerHandler.writeToInternalProtocol(returnMessage)