#!/usr/bin/env python3
# Copyright 2017 The Australian National University
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License 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.


class Callback:
    """
    Callback root class used by Python
    """

    def __init__(self, param_s):
        """
        :param param_s: parameter string for initialisation
        """
        pass

    def begin(self, kwds=None):
        """
        Begin measurement.
        """
        pass

    def end(self, kwds=None):
        """
        End measurement.
        """
        pass

    def report(self):
        """
        Report data to file.
        """
        pass


def get_callback(cb_name):
    """
    Import callback classes from submodule files,
    and dynamically select which class to return.
    NOTE: new Callback class implementations should be added here
    """
    from callback.cb_print import PrintCallback
    from callback.cb_time import TimeCallback
    from callback.cb_clock import ClockCallback
    name_dic = {
        'print': PrintCallback,
        'time': TimeCallback,
        'clock': ClockCallback,
    }
    cb_cls = name_dic[cb_name]
    return cb_cls