import dbus.mainloop.glib
from sugar.tutorius.TProbe import ProbeProxy
import sugar.tutorius.addon as addon

class Engine:
    """
    Driver for the execution of tutorials
    """

    def __init__(self):
        # FIXME Probe management should be in the probe manager
        dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
        self._probe = ProbeProxy("org.laptop.Calculate") 
        self._bm = None

    
    def launch(self, tutorialID):
	""" Launch a tutorial 
            @param tutorialID unique tutorial identifier used to retrieve it from the disk
        """
        if self._bm == None:
            self._bm = addon.create("BubbleMessage")
        self._bm.position = (300,300)
        self._bm.message = "Tutorial Started"

        self._probe.install(self._bm)
        

    def stop(self):
        """ Stop the current tutorial
        """
        self._probe.uninstall(self._bm)

    def pause(self):
        """ Interrupt the current tutorial and save its state in the journal
        """
        self._bm.message = "Tutorial State would be saved"
        self._probe.update(self._bm)