import tester.*;
/**
 * HtDC Lectures
 * Lecture 4: Methods for simple classes
 * 
 * Copyright 2013 Viera K. Proulx
 * This program is distributed under the terms of the 
 * GNU Lesser General Public License (LGPL)
 * 
 * @since 29 August 2013
 */
/*
 +---------------+
 | Book          | 
 +---------------+
 | String title  |
 | String author |
 | int price     | 
 +---------------+  
 */


// to represent a book in a bookstore
class Book{
    String title;
    String author;
    int price;
    
    // the constructor
    Book(String title, String author, int price) {
        this.title = title;
        this.author = author;
        this.price = price;
    }
    
    
    /* TEMPLATE:
     Fields:
     ... this.title ...         -- String
     ... this.author ...        -- String
     ... this.price ...         -- int
     
     Methods:
     ... this.salePrice(int) ... -- int
     ... this.reducePrice() ...  -- Book
     */
    
    // compute the sale price of this book given today's discount 
    // in percent of the priginal price
    int salePrice(int discount) {
        return this.price - (this.price * discount) / 100;
    }
    
    // produce a book like this one, but with the price reduced by 20%
    Book reducePrice(){
        return new Book(this.title, this.author, this.salePrice(20));
    }
}

// examples and tests for the class hierarchy that represents 
// books and authors
class ExamplesBooks {
    ExamplesBooks() {}
    
    Book htdp = new Book("HtDP", "FFK", 60);
    Book beaches = new Book("Beaches", "PC", 20);
    
    // test the method salePrice for the class Book
    boolean testSalePrice(Tester t) {
        return
        t.checkExpect(this.htdp.salePrice(30), 42) &&
        t.checkExpect(this.beaches.salePrice(20), 16);
    }
    
    // test the method reducePrice for the class Book
    boolean testReducePrice(Tester t) {
        return
        t.checkExpect(this.htdp.reducePrice(), 
                      new Book("HtDP", "FFK", 48)) &&
        t.checkExpect(this.beaches.reducePrice(), 
                      new Book("Beaches", "PC", 16));
    }
}