# Source code for taurus.core.taurusoperation

    #!/usr/bin/env python

    # ###########################################################################
    #
    # This file is part of Taurus
    #
    # http://taurus-scada.org
    #
    # Copyright 2011 CELLS / ALBA Synchrotron, Bellaterra, Spain
    #
    # Taurus is free software: you can redistribute it and/or modify
    # it under the terms of the GNU Lesser General Public License as published by
    # the Free Software Foundation, either version 3 of the License, or
    # (at your option) any later version.
    #
    # Taurus is distributed in the hope that it will be useful,
    # but WITHOUT ANY WARRANTY; without even the implied warranty of
    # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    # GNU Lesser General Public License for more details.
    #
    # You should have received a copy of the GNU Lesser General Public License
    # along with Taurus.  If not, see <http://www.gnu.org/licenses/>.
    #
    # ###########################################################################

    """This module contains the base taurus operation classes
    """

    __all__ = ["TaurusOperation", "WriteAttrOperation"]

    __docformat__ = "restructuredtext"

    from .util.log import Logger

    class TaurusOperation(Logger):
        def __init__(self, name="TaurusOperation", parent=None, callbacks=None):
            self.call__init__(Logger, name, parent)
            if callbacks is None:
                callbacks = []
            self._callbacks = callbacks
            self._dangerMessage = None
            self._isDangerous = False

        def getDevice(self):
            pass

        def setCallbacks(self, callbacks):
            self._callbacks = callbacks

        def getCallbacks(self):
            return self._callbacks

        def execute(self):
            for f in self._callbacks:
                f(operation=self)

        def isDangerous(self):
            return self._isDangerous

        def setDangerMessage(self, dangerMessage=None):
            """if dangerMessage is None, the operation is considered safe"""
            self._dangerMessage = dangerMessage
            self._isDangerous = dangerMessage is not None

        def getDangerMessage(self):
            return self._dangerMessage

        def resetDangerMessage(self):
            self.setDangerMessage(None)

    class WriteAttrOperation(TaurusOperation):
        def __init__(self, attr, value, callbacks=None):
            self.call__init__(
                TaurusOperation, "WriteAttrOperation", attr, callbacks=callbacks
            )
            self.attr = attr
            self.value = value

        def execute(self):
            self.attr.write(self.value)
            TaurusOperation.execute(self)