#!/usr/bin/python3
# -*- coding: utf-8 -*-


# +++++++++++++++++++++++ Lecture 2 starts here

# define parent class
class Parent:
    parentAttr = 100

    def __init__(self) -> None:
        print("Calling parent pseudo-constructor")

    def parent_method(self) -> None:
        print("Calling parent method")

    def set_attr(self, attr: int, attr2: int) -> None:
        # Class variables can be accessed:
        Parent.parentAttr = attr2
        # Class variables can be created:
        Parent.NewClassAttr = attr
        # Instance variables can be created or accessed:
        self.whatever = "hello"

    def get_attr(self) -> None:
        print("Parent attribute :", Parent.parentAttr, " and ", Parent.NewClassAttr)


class Child(Parent):  # define child class
    def __init__(self) -> None:
        """
        Note, parent __init__ is not called unless you do so explicitly here.
        """
        print("Calling child constructor")
        self.myInternalVar = "default"

    def child_method(self, inputVar: str) -> None:
        print("Calling child method")
        self.myInternalVar = inputVar

    def child_get(self) -> None:
        print(self.myInternalVar)


p1 = Parent()
p1.set_attr(300, 10)
p1.get_attr()
print(p1.whatever)
p1.whatever = "hey"
print(p1.NewClassAttr)
print(p1.parentAttr)

p2 = Parent()
p2.get_attr()
# p2.whatever (just an instance variable for p)

# We can add a new instance data member
p2.randomvar = 37
print(p2.randomvar)

# Which constructor is called now?
# instance of child
c = Child()
# child calls its method
c.child_method("hey")
c.child_get()
# calls parent's method
c.parent_method()
# again call parent's method
c.set_attr(200, 100)
# again call parent's method
c.get_attr()