import tester.*;

// some grocery items 
interface IItem { 
  // is this the same IItem as other? 
  boolean sameItem(IItem x); 
  
  // is this Coffee? 
  boolean isCoffee(); 
  // convert this to Coffee (if feasible) 
  Coffee toCoffee(); 
  
  // is this Tea? 
  boolean isTea(); 
  // convert this to Tea (if feasible) 
  Tea toTea(); 
} 

// to represent a coffee in a grocery store
class Coffee implements IItem 
{ 
  private String origin; 
  private int price; 
  
  // the constructor
  Coffee(String origin, int price){ 
    this.origin = origin; 
    this.price = price; 
  } 
  
  public boolean isCoffee(){ 
    return true; 
  } 
  public boolean isTea(){ 
    return false; 
  } 
  
  public Coffee toCoffee(){ 
    return this; 
  } 
  public Tea toTea(){ 
    throw new RuntimeException("not a tea"); 
  } 
  
  public boolean sameItem(IItem other){ 
    return (other.isCoffee()) 
    && other.toCoffee().sameCoffee(this); 
  } 
  
  // is this the same Coffee as other? 
  private boolean sameCoffee(Coffee other){ 
    return 
    this.origin.equals(other.origin) 
    && this.price == other.price; 
  } 
} 

//to represent a tea in a grocery store
class Tea implements IItem 
{ 
  private String kind; 
  private int price; 
  
  // the constructor
  Tea(String kind, int price){ 
    this.kind = kind; 
    this.price = price; 
  } 
  
  public boolean isTea(){ 
    return true; 
  } 
  public boolean isCoffee(){ 
    return false; 
  } 
  
  public Tea toTea(){ 
    return this; 
  } 
  public Coffee toCoffee(){ 
    throw new RuntimeException("not a coffee"); 
  } 
  
  public boolean sameItem(IItem other) 
  { 
    return other.isTea() 
    && other.toTea().sameTea(this); 
  } 
  
  // is this the same Tea as other? 
  private boolean sameTea(Tea other){ 
    return 
    this.kind.equals(other.kind) 
    && this.price == other.price; 
  } 
} 

class ExamplesGroceryItems{
  ExamplesGroceryItems(){}
  
  IItem tea1 = new Tea("Oolong", 200);
  IItem tea2 = new Tea("Oolong", 300);
  IItem tea3 = new Tea("Oolong", 300);
  IItem coffee1 = new Coffee("Kona", 300);
  IItem coffee2 = new Coffee("Java", 200);
  IItem coffee3 = new Coffee("Java", 200);
  
  boolean testSameItem(Tester t){
    return
    t.checkExpect(this.tea1.sameItem(this.tea2), false) &&
    t.checkExpect(this.tea3.sameItem(this.tea2), true) &&
    t.checkExpect(this.coffee1.sameItem(this.coffee2), false) &&
    t.checkExpect(this.coffee3.sameItem(this.coffee2), true) &&
    t.checkExpect(this.coffee3.sameItem(this.tea2), false) &&
    t.checkExpect(this.tea3.sameItem(this.coffee1), false) &&
    t.checkException(new RuntimeException("not a tea"),
        this.coffee1, "toTea") &&
        t.checkException(new RuntimeException("not a coffee"),
            this.tea2, "toCoffee");
  }

}