# Copyright (C) 2009, Tutorius.org
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

from ..actions import *

class OnceWrapper(Action):
    """
    Wraps a class to perform an action once only

    This ConcreteActions's do() method will only be called on the first do()
    and the undo() will be callable after do() has been called
    """

    action = TAddonProperty()

    def __init__(self, action):
        Action.__init__(self)
        self._called = False
        self._need_undo = False
        self.action = action

    def do(self, **kwargs):
        """
        Do the action only on the first time
        """
        if not self._called:
            self._called = True
            self.action.do()
            self._need_undo = True

    def undo(self):
        """
        Undo the action if it's been done
        """
        if self._need_undo:
            self.action.undo()
            self._need_undo = False


__action__ = {
    'name' : 'OnceWrapper',
    'display_name' : 'Execute an action only once',
    'icon' : 'once_wrapper',
    'class' : OnceWrapper,
    'mandatory_props' : ['action'] ,
    'test' : True
}