import draw.*;
import geometry.*;
/*
--- CSU213 Fall 2006 Lab Notes ---------
Copyright 2006 Viera K. Proulx

Lab 5: All people are equal, but some are more equal than others...
*/

/* 
Goal: Learn how to determine the equality of two self-referential data                                    
*/

/*
                 +------------------------+                    
                 | LoStars                |<------------------+
                 +------------------------+                   |
                 +------------------------+                   |
                 | LoStars move()         |                   |
                 +------------------------+                   |
                             |                                |
                            / \                               |
                            ---                               |
                             |                                |
              -------------------------------                 |
              |                             |                 |
  +------------------------+    +------------------------+    |
  | MTLoStars              |    | ConsLoStars            |    |
  +------------------------+    +------------------------+    |
  +------------------------+  +-| Star first             |    |
  | LoStars move()         |  | | LoStars rest           |-+  |
  +------------------------+  | +------------------------+ |  |
                              | | LoStars move()         | |  |
                              | +------------------------+ |  |
                              |                            +--+
                              | 
                              |                           
                              v
               +------------------------+        +-------+
               | Star                   |        | Posn  |
               +------------------------+        +-------+
             +-| CartPt loc             |        | int x |
             | | int lifespan           |        | int y |
             | +------------------------+        +-------+
             | | Star move()            |        +-------+
             | +------------------------+            |
             |                                      / \
             |                                      ---      
             v                                       |
+------------------------------------------------------------------+
| CartPt                                                           |
+------------------------------------------------------------------+
+------------------------------------------------------------------+
| CartPt translate(int dx, int dy)                                 |
+------------------------------------------------------------------+
*/

//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
// to represent a cartesian point
class CartPt extends Posn {

  CartPt(int x, int y) {
    super(x, y);
  }

  // produce this point translated by the given dx and dy
  CartPt translate(int dx, int dy){
    return new CartPt(this.x + dx, this.y + dy);
  }
}

//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
// to represent a shooting star
class Star {
  CartPt loc;
  int lifespan;

  Star(CartPt loc, int lifespan) {
    this.loc = loc;
    this.lifespan = lifespan;
  }

  // move this star horizontally dx pixels and vertically dy pixels 
  Star move(int dx, int dy){
    return new Star(this.loc.translate(dx, dy), 
                    this.lifespan - 1);
  }
}

//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
// to represent a list of Stars
abstract class ALoStars {

  // produce a list of all stars in this list moved by dx and dy
  abstract ALoStars move(int dx, int dy);
}

//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
// to represent an empty llist of Stars
class MTLoStars extends ALoStars {

  MTLoStars() {}

  // produce a list of all stars in this list moved by dx and dy
  ALoStars move(int dx, int dy){
    return this;
  }
}

//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
// to represent a non-empty list of Starss
class ConsLoStars extends ALoStars {
  Star first;
  ALoStars rest;

  ConsLoStars(Star first, ALoStars rest) {
    this.first = first;
    this.rest = rest;
  }

  // produce a list of all stars in this list moved by dx and dy
  ALoStars move(int dx, int dy){
    return new ConsLoStars(this.first.move(dx, dy),
                           this.rest.move(dx, dy));
  }
}


class Examples {
  Examples(){}
 
// Sample data
Star s1 = new Star(new CartPt(20, 40), 10);
Star s2 = new Star(new CartPt(30, 40), 5);
Star s3 = new Star(new CartPt(10, 30), 8);
Star s4 = new Star(new CartPt(10, 50), 10);

ALoStars mtstars = new MTLoStars();
ALoStars list1 = new ConsLoStars(s1, mtstars);
ALoStars list2 = new ConsLoStars(s2, list1);
ALoStars list3 = new ConsLoStars(s3, list2);
ALoStars list4 = new ConsLoStars(s4, list3);

// dealing with the empty list
boolean testEmptyLists = true;

// dealing with a list with one item
boolean testConsLists = true;

// dealing with a list with more than one item
boolean testMultiLists = true;

  // test the method move
  boolean testMove(){
    return true;
  }


  boolean testAll(){
    return this.testMove();
  }
}