#class=> Library
#Layer of Encapsulation=> Display available books, lend a book, add a book
#class=> Customer
#Layer of abstraction => request a book, return a book

print("\t\t\tBLESSING'S LIBRARY")
print( )




class Library():
    def __init__(self,list_of_books):
        self.availablebooks = list_of_books

    def display_available_books(self):
        print( )
        print("Available Books: ")
        for book in self.availablebooks:
            print(book)



    def lend_a_book(self,requestedBook):
        print( )
        if requestedBook in self.availablebooks:
            print(f"You have borrowed {requestedBook} ")
            self.availablebooks.remove(requestedBook)
        else:
            print("Sorry the book you requested isn't available")


    def add_a_book(self, returnedBook):
        self.availablebooks.append(returnedBook)
        print("You have returned the book. Thank You!")



class Customer():

    def request_a_book(self):
        print("Enter the book you want to request: ")
        self.book = input( )
        return self.book

    def return_a_book(self):
        print("Enter the name of the book you are returning : ")
        self.book = input( )
        return self.book

library = Library(["K.A Stroud Algebra", "Pressupositional Apologetics","V.K Mheta","How to think Like a Computer Scientist", "A Complete Introduction to Python", "Advanced Engineering Mathematics", "Introduction to Object-Oriented Programming", "Intoduction to Numpy"])
customer = Customer()

while True:
    print("Press 1 to display the available books")
    print("Press 2 to request a book")
    print("Press 3 to return a book")
    print("Press 4 to exit")


    useroption = int(input( ))

    if useroption == 1:
        library.display_available_books()
    elif useroption ==2:
        request = customer.request_a_book()
        library.lend_a_book(request)
    elif useroption ==3:
        returnedBook = customer.return_a_book()
        library.add_a_book(returnedBook)
    elif useroption ==4:
        quit()