#
# demo file for objects and inheritance
# make a class of vehicles, which is inherited
# from by the car and truck classes
#              pmb, 10/15/02
# put everything for a vehicle here
class vehicle:
    # initialize method. called when vehicle is created
    def __init__(self):
        self.gas = 10
        self.v = 0
        self.pos = 0
        print "made a vehicle"
    # fill up gastank
    def gasUp(self,fuel):
        self.gas = self.gas + fuel
        print "vehicle gassed Up"
    # go faster
    def goFaster( self ):
        self.v = self.v + 1
    # stop!
    def stop( self ):
        self.v = 0.0
    # set mass of vehicle
    def setMass ( self, m ):
        self.mass = m
    # update position
    def updatePos ( self ):
        if ( self.gas > 0 ):
            self.pos = self.pos + self.v * 0.04
            self.gas = self.gas - 0.5
            self.mass = self.mass -0.5
        else:
            self.v =0;
            print "Out of gas!"

# now put stuff just needed for a car    
class car(vehicle):
    # init- called automatically when its made
    def __init__(self):
        # must call init for superclass manually
        vehicle.__init__(self)
        self.passengers=[]
        print "made a car"
    # add a new passenger
    def addPass(self, newP):
        self.passengers.append( newP )
        self.mass = self.mass + newP.mass
        print "added passenger ", self.passengers
# things just needed for a truck
class truck(vehicle):
    # next line is a docstring
    # print it with print truck.__doc__
    "The truck class- inherits from vehicle. addCargo is additional method."
    def __init__(self):
        # make a vehicle manually
        vehicle.__init__(self)
        self.cargo=[]
        print "made a truck"
    # add some cargo
    def addCargo(self, stuff ):
        self.cargo.append( stuff )
        self.mass = self.mass + stuff.mass
        print "added cargo ", self.cargo

# a superclass of things to carry
class things:
    "A superclass of carryable items."
    # this can probly go away
    def __init__(self):
        return
    def setMass( self, m ):
        self.mass = m

# two inheriting subclasses, passengers and cargo
class passenger( things ):
    "A class of passengers. Inherits from things class."
    def __init__(self):
        things.__init__(self)
    # passengers ahve names
    def setName(self, n ):
        self.name = n

#cargo inherits from things
class cargo(things ):
    def __init__(self):
        things.__init__(self)
    # cargo has names too
    def setName(self, n ):
        self.name = n
        
# main program here
#
# make some passengers
joe = passenger()
joe.setMass ( 150 )
joe.setName("Joe")
print joe.__doc__
mary = passenger()
mary.setMass ( 130 )
mary.setName ("Mary")

# make some cargo
widgets = cargo()
widgets.setMass ( 300 )
gadgets = cargo()
gadgets.setMass ( 500 )

# make a car
toronado= car()
toronado.setMass( 10000 )
toronado.addPass( joe )
toronado.goFaster()
toronado.goFaster()

# make another car
vwbug = car()
vwbug.setMass ( 1500 )
vwbug.addPass ( mary )
vwbug.goFaster()

# make a truck
semi = truck()
semi.setMass ( 80000 )
semi.addCargo(widgets)
semi.addCargo(gadgets)
semi.goFaster()
print semi.__doc__

#
ontheroad= [ toronado, vwbug, semi ]
while semi.gas > 5:
    for aVehicle in ontheroad:
        print "vehicle mass ",aVehicle.mass,
        print "velocity ", aVehicle.v
        aVehicle.updatePos()
        aVehicle.goFaster()