#
# Example of inheritance -- basic animal classes with error checking
#
# Matt Bishop, MHI 289I, Fall 2019
#

#
# base class: animal
#
class Animal:

    # expected to be one of these
    kindofanimal = [ "lion", "bear", "dog", "giraffe", "cat" ]

    def __init__(self, kind):
        # if it's in the list, OK -- otherwise disallow it
        if kind in Animal.kindofanimal:
            self.kind = kind
        else:
            self.kind = None

    def __str__(self):
        # if it's not in the list, say so
        if self.kind:
            return "Your animal is a " + self.kind
        else:
            return "Your animal is of an unknown type"

#
# now the subclass, as cat is an animal
#
class Cat(Animal):

    # breeds of cats
    catbreed = [ "Persian", "Manx", "Siamese", "domestic" ]

    def __init__(self, breed):
        # instatiate as an animal
        super().__init__("cat")
        # add in the new attribute
        if breed in Cat.catbreed:
            self.breed = breed
        else:
            self.breed = None

    def __str__(self):
        # if it's not in the list, say so
        if self.breed:
            return super().__str__() + "; breed is "+self.breed
        else:
            return super().__str__() + "; the breed is unknown"

#
# nw the example usage
#
# first, the class -- show a lion
a = Animal("lion")
print(a)

# now, the subclass, with a valid breed
c = Cat("Persian")
print(c)

# and the subclass with an invalid breed
c2 = Cat("Himalayan")
print(c2)