package a3Doubledispatch;
/***********************************************
 *  CS2510 Spring 2012 
 *  Coffee, done right
 ***********************************************/

import a2Safecasting.ExamplesShapesSafeCasts;
import tester.*;

interface Drink {
  // Is this drink the same as that drink?
  Boolean same(Drink that);

  // Is this drink the same as that tea?
  Boolean sameTea(Tea that);
  // Is this drink the same as that coffee?
  Boolean sameCoffee(Coffee that);
  // Is this drink the same as that latte?
  Boolean sameLatte(Latte latte);
}

abstract class ADrink {
  public Boolean sameTea(Tea that) { return false; }
  public Boolean sameCoffee(Coffee that) { return false; }
  public Boolean sameLatte(Latte that) { return false; }
}

class Tea extends ADrink implements Drink {
  // Is this tea the same as that drink?
  public Boolean same(Drink that) {
    return that.sameTea(this);
  }

  public Boolean sameTea(Tea that) {
    return true;
  }
}

class Coffee extends ADrink implements Drink {
  // Is this coffee the same as that drink?
  public Boolean same(Drink that) {
    return that.sameCoffee(this);
  }

  public Boolean sameCoffee(Coffee that) { 
    return true;
  }
}

class Latte extends Coffee {
  public Boolean same(Drink that) {
    return that.sameLatte(this);
  }

  public Boolean sameLatte(Latte that) {
    return true;
  }

  public Boolean sameCoffee(Coffee that) {
    return false;
  }
}

public class ExamplesDoubleDispatch {
  ExamplesDoubleDispatch(){}

  public static ExamplesDoubleDispatch examplesInstance = 
      new ExamplesDoubleDispatch();
  
  Drink t = new Tea();
  Drink c = new Coffee();
  Drink l = new Latte();

  public Boolean testSameDrink(Tester t) {
    return t.checkExpect(this.t.same(this.t), true)
        && t.checkExpect(this.c.same(this.c), true)
        && t.checkExpect(this.t.same(this.c), false)
        && t.checkExpect(this.c.same(this.t), false);
  }
  public Boolean testSameCoffee(Tester t) {
    return t.checkExpect(this.l.same(this.c), false)  // works!
        && t.checkExpect(this.c.same(this.l), false); // still works!
  }



  // run all tests
  public static void main(String[] argv){
    ExamplesDoubleDispatch e = 
        new ExamplesDoubleDispatch();
    Tester.runReport(e, false, false);
  }

}