#  AnimalsSolutions.py   Copyright (c) Kari Laitinen

#  http://www.naturalprogramming.com

#  2009-01-06  File created.
#  2022-12-28  Converted to Python 3.

#  Solutions to the exercises with Animals.py

class  Animal :

   def __init__( self, first_parameter = "default animal",
                       second_parameter = "nameless"  ) :

      if isinstance( first_parameter, str ) :

         #  The given parameter is a string. We suppose that a new
         #  Animal object with the given species name is being constructed.

         self.species_name      =  first_parameter
         self.animal_name       =  second_parameter
         self.stomach_contents  =  ""

      elif isinstance( first_parameter, Animal ) :

         #  A reference to an Animal object was given as an actual parameter.
         #  The new Animal object will be a copy of the given Animal object.

         self.species_name      =  first_parameter.species_name
         self.animal_name       =  first_parameter.animal_name
         self.stomach_contents  =  first_parameter.stomach_contents

      else :

         print( "\n Unacceptable object was given to Animal constructor." )


   def feed( self, food_for_this_animal ) :

      if isinstance( food_for_this_animal, str ) :

         self.stomach_contents  =  \
             self.stomach_contents  +  food_for_this_animal  +  ", " 

      elif isinstance( food_for_this_animal, Animal ) :

         self.stomach_contents  =  \
             self.stomach_contents  +  food_for_this_animal.animal_name  +  ", " 

         food_for_this_animal.animal_name = "Eaten animal"


   def make_speak( self ) :

      print(  "\n Hello, I am a "  +  self.species_name  +  " named "  \
           + self.animal_name, end="" )

      if ( len( self.stomach_contents ) == 0 ) :

         print( "\n My stomach is empty." )

      else :

         print( "\n I have eaten: "  +  self.stomach_contents  +  "\n" )


#  The main program begins here.

cat_object  =  Animal( "cat" )
dog_object  =  Animal( "vegetarian dog" )

cat_object.feed( "fish" )
cat_object.feed( "chicken" )

dog_object.feed( "salad" )
dog_object.feed( "potatoes" )

another_cat  =  Animal( cat_object )

another_cat.feed( "milk" )

cat_object.make_speak()
dog_object.make_speak()
another_cat.make_speak()

default_animal = Animal()
default_animal.make_speak()

tiger_object  =  Animal( "tiger", "Richard" )
cow_object    =  Animal( "cow", "Bertha" )

tiger_object.feed( cow_object )
tiger_object.make_speak()
cow_object.make_speak()