import geometry.*;

// -----------------------------------------------------------------------------
// a data representation of moving, geometric objects
// a Circ is one kind of mobile object
// an Squr is the other mobile animal
interface IMobile {
  // move this object for t clock ticks
  IMobile move(int t);

  // what is the base area of this object 
  double area(); 

  // how much volume does this object traverse as it moves for t clock ticks
  double volume(int t); 
}

abstract class AMobile implements IMobile {
  protected Posn p; 
  protected Velocity v; 
  protected AMobile(Posn p, Velocity v) {
    this.p = p; 
    this.v = v; 
  }

  public double volume(int t) {
    double height = v.speed() * t; 
    return height * area();
  }  
}

class Circ extends AMobile {
  private double radius = 50;
  public Circ(Posn p, Velocity v, double radius) {
    super(p,v);
    this.radius = radius;
  }
  
  public IMobile move(int t) {
    return new Circ(v.translate(p),v,radius);
  }

  public double area() {
    return Math.PI * radius * radius; 
  }
}

class Squr extends AMobile {
  private double size = 2; 
  public Squr(Posn p, Velocity v, double size) {
    super(p,v);
    this.size = size;
  }
  
  public IMobile move(int t) {
    return new Squr(v.translate(p),v,size);
  }
  
  public double area() {
    return size * size; 
  }
}

// a data representation of 2D velocity 
class Velocity {
  private double deltaX; 
  private double deltaY;
  public Velocity(double deltaX, double deltaY) {
    this.deltaX = deltaX; 
    this.deltaY = deltaY;
  }
  
  // move the given Posn by this velocity 
  public Posn translate(Posn p) {
    return new Posn((int)(p.x + deltaX),(int)(p.y + deltaY));
  }

  // the distance (measure) travelled according to this velocity 
  public double speed() {
    return Math.sqrt(deltaX * deltaX + deltaY * deltaY);
  }
}

// -----------------------------------------------------------------------------
// tests for Velocity 
class VelExamples {
  Velocity v1 = new Velocity(3,4);
  Velocity v2 = new Velocity(12,5); 
  
  boolean b1 = check v1.speed() expect 5 within .0001;
  boolean b2 = check v2.speed() expect 13 within .1; 
  
  boolean b3 = check v1.translate(new Posn(0,0)) expect new Posn(3,4); 
  boolean b4 = check v1.translate(new Posn(10,20)) expect new Posn(13,24); 
}

// tests for movable objects 
class Examples {
  VelExamples vex = new VelExamples();
  Velocity v = vex.v1;

  IMobile c = new Circ(new Posn(10,10),v,50);
  IMobile s = new Squr(new Posn(20,20),v,10);
  
  boolean bm0 = check c.move(1) expect new Circ(new Posn(13,14),v,50);
  boolean bm1 = check s.move(1) expect new Squr(new Posn(23,24),v,10);
  
  boolean b1 = check c.volume(1) expect 5.0 * 50 * 50 * Math.PI within .1;
  boolean b2 = check s.volume(2) expect 1000 within .0001;
}