# 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
"""
This module defines Actions that can be done and undone on a state
"""
from gettext import gettext as _

from sugar.tutorius import gtkutils
from dialog import TutoriusDialog
import overlayer
from sugar.tutorius.editor import WidgetIdentifier
from sugar.tutorius.services import ObjectStore


class Action(object):
    """Base class for Actions"""
    def __init__(self):
        object.__init__(self)

    def do(self, **kwargs):
        """
        Perform the action
        """
        raise NotImplementedError("Not implemented")

    def undo(self):
        """
        Revert anything the action has changed
        """
        pass #Should raise NotImplemented?

    def get_properties(self):
        if not hasattr(self, "_props") or self._props is None:
            self._props = []
            for i in dir(self.__class__):
                if type(getattr(self.__class__,i)) is property:
                    self._props.append(i)
        return self._props

class OnceWrapper(object):
    """
    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
    """
    def __init__(self, action):
        self._action = action
        self._called = False
        self._need_undo = False

    def do(self):
        """
        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
        
    def get_properties(self):
        return self._action.get_properties()

class DialogMessage(Action):
    """
    Shows a dialog with a given text, at the given position on the screen.

    @param message A string to display to the user
    @param pos A list of the form [x, y]
    """
    def __init__(self, message, pos=[0,0]):
        super(DialogMessage, self).__init__()
        self._message = message
        self._position = pos
        self._dialog = None

    def set_message(self, msg):
        self._message = msg
        
    def get_message(self):
        return self._message
    
    message = property(fget=get_message, fset=set_message)
    
    def set_pos(self, x, y):
        self._position = [x, y]
        
    def get_pos(self):
        return self._position
    
    position = property(fget=get_pos, fset=set_pos)

    def do(self):
        """
            Show the dialog
        """
        self._dialog = TutoriusDialog(self._message)
        self._dialog.set_button_clicked_cb(self._dialog.close_self)
        self._dialog.set_modal(False)
        self._dialog.move(self.position[0], self.position[1])
        self._dialog.show()

    def undo(self):
        """
            Destroy the dialog
        """
        if self._dialog:
            self._dialog.destroy()
            self._dialog = None


class BubbleMessage(Action):
    """
    Shows a dialog with a given text, at the given position on the screen.

    @param message A string to display to the user
    @param pos A list of the form [x, y]
    @param speaker treeish representation of the speaking widget
    """
    def __init__(self, message, pos=[0,0], speaker=None, tailpos=None):
        Action.__init__(self)
        self._message = message
        self._position = pos

        self.overlay = None
        self._bubble = None
        self._speaker = None
        self._tailpos = tailpos

    def set_message(self, msg):
        self._message = msg
    def get_message(self):
        return self._message
    message = property(fget=get_message, fset=set_message, doc="Message displayed to the user")

    def set_pos(self, x, y):
        self._position = [x, y]
    def get_pos(self):
        return self._position
    position = property(fget=get_pos, fset=set_pos, doc="Position in [x, y] on the screen")
    
    def set_tail_pos(self, x, y):
        self._tailpos = [x, y]
    def get_tail_pos(self):
        return self._tailpos
    tail_pos = property(fget=get_tail_pos, fset=set_tail_pos, doc="Position the tail of the bubble must point to")
    
    def do(self):
        """
            Show the dialog
        """
        # get or inject overlayer
        self.overlay = ObjectStore().activity._overlayer
        # FIXME: subwindows, are left to overlap this. This behaviour is
        # undesirable. subwindows (i.e. child of top level windows) should be
        # handled either by rendering over them, or by finding different way to
        # draw the overlay.

        if not self._bubble:
            x, y = self._position
            # TODO: tails are relative to tailpos. They should be relative to
            # the speaking widget. Same of the bubble position.
            self._bubble = overlayer.TextBubble(text=self._message,
                tailpos=self._tailpos)
            self._bubble.show()
            self.overlay.put(self._bubble, x, y)
            self.overlay.queue_draw()

    def undo(self):
        """
            Destroy the dialog
        """
        if self._bubble:
            self._bubble.destroy()
            self._bubble = None
        
class WidgetIdentifyAction(Action):
    def __init__(self):
        self.activity = None
        self._dialog = None

    def do(self):
        os = ObjectStore()
        if os.activity:
            self.activity = os.activity

            self._dialog = WidgetIdentifier(self.activity)
            self._dialog.show()


    def undo(self):
        if self._dialog:
            self._dialog.destroy()

class ChainAction(Action):
    """Utility class to allow executing actions in a specific order"""
    def __init__(self, *actions):
        """ChainAction(action1, ... ) builds a chain of actions"""
        self._actions = actions

    def do(self,**kwargs):
        """do() each action in the chain"""
        for act in self._actions:
            act.do(**kwargs)

    def undo(self):
        """undo() each action in the chain, starting with the last"""
        for act in reversed(self._actions):
            act.undo()

class DisableWidgetAction(Action):
    def __init__(self, target):
        """Constructor
        @param target target treeish
        """
        Action.__init__(self)
        self._target = target
        self._widget = None

    def do(self):
        """Action do"""
        os = ObjectStore()
        if os.activity:
            self._widget = gtkutils.find_widget(os.activity, self._target)
            if self._widget:
                self._widget.set_sensitive(False)

    def undo(self):
        """Action undo"""
        if self._widget:
            self._widget.set_sensitive(True)
            
class TypeTextAction(Action):
    """
    Simulate a user typing text in a widget
    Work on any widget that implements a insert_text method
    
    @param widget The treehish representation of the widget
    @param text the text that is typed
    """
    def __init__(self, widget, text):
        Action.__init__(self)
        
        self._widget = widget
        self._text = text
        
    def do(self, **kwargs):
        """
        Type the text
        """
        widget = gtkutils.find_widget(ObjectStore().activity, self._widget)
        if hasattr(widget, "insert_text"):
            widget.insert_text(self._text, -1)
            
    def undo(self):
        """
        no undo
        """
        pass
        
class ClickAction(Action):
    """
    Action that simulate a click on a widget    
    Work on any widget that implements a clicked() method
    
    @param widget The threehish representation of the widget
    """
    def __init__(self, widget):
        Action.__init__(self)
        self._widget = widget
        
    def do(self):
        """
        click the widget
        """
        widget = gtkutils.find_widget(ObjectStore().activity, self._widget)
        if hasattr(widget, "clicked"):
            widget.clicked()
        
    def undo(self):
        """
        No undo
        """
        pass