# student.py

# a "class" is a data type (pre-compile time definition ONLY)
# a class is made up of attributes (state) and functions (behavior)

# an "object" is a run-time instance of a "class"

# OOP is optional in Python (unlike Java)

# OOP: inheritance, composition, polymorphism
#      operator overloading
#      specialization/generalization (customization via inheritance)

class Student:
    def __init__( self, name, major='EXPL', gpa=4.0 ):
        self.name = name
        self.major = major
        self.gpa = gpa
        self.someotherattribute = 123
        # self is the newly constructed instance object
    def lastName( self ):
        return self.name.split()[-1]
    def __str__( self ):    #  Java toString()
        #return 'Student: %s, %s (GPA %.2f)' % ( self.name, self.major, self.gpa )
        return 'Student: %s, %s (GPA %.2f)' % ( self.lastName(), self.major, self.gpa )

class GraduateStudent( Student ):   # subclass of Student
    # purpose of subclassing here is for specialization
    # -- inherits everything from the Student class
    # modify below by overriding behavior/functions.....
    def lastName( self ):
        return 'The ' + Student.lastName( self )
    def writeThesis( self ):
        print( 'okay. all done.' )
    

# if we run this code, then __name__ == '__main__'
# if we import student, then __name__ == 'student'
if __name__ == '__main__':
    s1 = Student( 'David Goldschmidt', major='CSCI' )
    s3 = Student( 'Lindsay Lohan', gpa=0.6 )
    print( s1.name, s1.major, s1.gpa )
    s1.major = 'ENGL'
    print( s1.lastName() )    # lastName( s1 )

    s2 = GraduateStudent( 'Kim Kardashian', '????', 1.2 )
    print( s2.name, s2.major, s2.gpa )
    print( s2.lastName() )  # use the most specific version of this function

    print( s2 )   # invokes the __str__() function
    print( s1 )


    L = [ s1, s2, s3, 5 ]
    for object in L:
        print( object )