# Copyright (C) 2009, Tutorius.org
# Copyright (C) 2009, Michael Janelle-Montcalm <michael.jmontcalm@gmail.com>
#
# 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
"""
Core Tests

This module contains all the tests that pertain to the usage of the Tutorius
Core. This means that the Event Filters, the Finite State Machine and all the 
related elements and interfaces are tested here.

"""

import unittest

import logging
from sugar.tutorius.actions import Action, OnceWrapper
from sugar.tutorius.core import *
from sugar.tutorius.filters import *

# Helper classes to help testing
class SimpleTutorial(Tutorial):
    """
    Fake tutorial
    """
    def __init__(self, start_name="INIT"):
        #Tutorial.__init__(self, "Simple Tutorial", None)
        self.current_state_name = start_name
        self.activity = "TODO : This should be an activity"
    
    def set_state(self, name):
        self.current_state_name = name

class TrueWhileActiveAction(Action):
    """
    This action's active member is set to True after a do and to False after
    an undo.
    
    Used to verify that a State correctly triggers the do and undo actions.
    """
    def __init__(self):
        self.active = False
        
    def do(self):
        self.active = True
        
    def undo(self):
        self.active = False


class CountAction(Action):
    """
    This action counts how many times it's do and undo methods get called
    """
    def __init__(self):
        self.do_count = 0
        self.undo_count = 0

    def do(self):
        self.do_count += 1

    def undo(self):
        self.undo_count += 1

class TriggerEventFilter(EventFilter):
    """
    This event filter can be triggered by simply calling its execute function.
    
    Used to fake events and see the effect on the FSM.
    """
    def __init__(self, next_state):
        EventFilter.__init__(self, next_state)
        self.toggle_on_callback = False
    
    def install_handlers(self, callback, **kwargs):
        """
        Forsakes the incoming callback function and just set the inner one.
        """
        self._callback = self._inner_cb
    
    def _inner_cb(self, event_filter):
        self.toggle_on_callback = not self.toggle_on_callback

class BaseActionTests(unittest.TestCase):
    def test_do_unimplemented(self):
        act = Action()
        try:
            act.do()
            assert False, "do() should trigger a NotImplemented"
        except NotImplementedError:
            assert True, "do() should trigger a NotImplemented"

    def test_undo(self):
        act = Action()
        act.undo()
        assert True, "undo() should never fail on the base action"


class OnceWrapperTests(unittest.TestCase):
    def test_onceaction_toggle(self):
        """
        Validate that the OnceWrapper wrapper works properly using the
        CountAction
        """
        act = CountAction()
        wrap = OnceWrapper(act)

        assert act.do_count == 0, "do() should not have been called in __init__()"
        assert act.undo_count == 0, "undo() should not have been called in __init__()"

        wrap.undo()

        assert act.undo_count == 0, "undo() should not be called if do() has not been called"

        wrap.do()
        assert act.do_count == 1, "do() should have been called once"

        wrap.do()
        assert act.do_count == 1, "do() should have been called only once"

        wrap.undo()
        assert act.undo_count == 1, "undo() should have been called once"

        wrap.undo()
        assert act.undo_count == 1, "undo() should have been called only once"


# State testing class
class StateTest(unittest.TestCase):
    """
    This class has to test the State interface as well as the expected 
    functionality.
    """
    
    def test_action_toggle(self):
        """
        Validate that the actions are properly done on setup and undone on
        teardown.
        
        Pretty awesome.
        """
        act = TrueWhileActiveAction()
        
        state = State("action_test", action_list=[act])
        
        assert act.active == False, "Action is not initialized properly"
        
        state.setup()
        
        assert act.active == True, "Action was not triggered properly"
        
        state.teardown()
        
        assert act.active == False, "Action was not undone properly"
    
    def test_event_filter(self):
        """
        Tests the fact that the event filters are correctly installed on setup
        and uninstalled on teardown.
        """
        event_filter = TriggerEventFilter("second_state")
        
        state = State("event_test", event_filter_list=[event_filter])
        state.set_tutorial(SimpleTutorial())
        
        assert event_filter.toggle_on_callback == False, "Wrong init of event_filter"
        assert event_filter._callback == None, "Event filter has a registered callback before installing handlers"
        
        state.setup()
        
        assert event_filter._callback != None, "Event filter did not register callback!"
        
        # 'Trigger' the event - This is more like a EventFilter test.
        event_filter.do_callback()
        
        assert event_filter.toggle_on_callback == True, "Event filter did not execute callback"
        
        state.teardown()
        
        assert event_filter._callback == None, "Event filter did not remove callback properly"
    
    def test_warning_set_tutorial_twice(self):
        """
        Calls set_tutorial twice and expects a warning on the second.
        """
        state = State("start_state")
        tut = SimpleTutorial("First")
        tut2 = SimpleTutorial("Second")
        
        state.set_tutorial(tut)
        
        try:
            state.set_tutorial(tut2)
            assert False, "No RuntimeWarning was raised on second set_tutorial"
        except :
            pass
    
    
if __name__ == "__main__":
    unittest.main()