import java.awt.Color;
import java.util.ArrayList;
import java.util.Random;

/**
 * Marine Biology Simulation:
 * The BDFish class represents a breeding and dying fish subclass in
 * the Marine Biology Simulation.
 * Each BDfish has a unique ID, which remains constant throughout its
 * life. A BDfish also maintains information about its location and
 * direction in the environment.
 **/

public class BDFish extends Fish
{
  private double probOfBreeding;  // defines likelihood in each timestep
  private double probOfDying;  // defines likelihood in each timestep

  // constructors and related helper methods

  /** Constructs a BDFish at specified location in a given environment.
   *  The BDFish is assigned a random direction and random color.
   *  (Precondition: parameters are non-null.)
   *  @param env	environment in which fish will live
   *  @param loc	location of the new fish in <code>env</code>
   **/
  public BDFish(Environment env, Location loc)
  {
    // Construct and initialize the attributes inherited from Fish.
    super(env, loc, env.randomDirection());
    // Define the likelihood that a BDFish will breed or die
    // myAge initialization provided, to be used if desired
    probOfBreeding = 1.0/7.0;
    probOfDying = 1.0/5.0;
  }

  /** Constructs a BDFish at the specified location and direction in a
   *  given environment. The BDFish is assigned a random color.
   *  (Precondition: parameters are non-null.)
   *  @param env	environment in which fish will live
   *  @param loc	location of the new fish in <code>env</code>
   *  @param dir	direction the new fish is facing
   **/
  public BDFish(Environment env, Location loc, Direction dir)
  {
    // Construct and initialize the attributes inherited from Fish.
    super(env, loc, dir);
    // Define the likelihood that a BDFish will breed or die
    // myAge initialization provided, to be used if desired
    probOfBreeding = 1.0/7.0;
    probOfDying = 1.0/5.0;
  }

  /** Constructs a BDFish of the specified color at the specified
   *  location and direction.
   *  (Precondition: parameters are non-null.)
   *  @param env	environment in which fish will live
   *  @param loc	location of the new fish in <code>env</code>
   *  @param dir	direction the new fish is facing
   *  @param col	color of the new fish
   **/
  public BDFish(Environment env, Location loc, Direction dir, Color col)
  {
    // Construct and initialize the attributes inherited from Fish.
    super(env, loc, dir, col);
    // Define the likelihood that a BDFish will breed or die
    // myAge initialization provided, to be used if desired
    probOfBreeding = 1.0/7.0;
    probOfDying = 1.0/5.0;
  }

  /** Returns a string representing key information about this BDfish.
   *  @return a string indicating the fish's ID and location
   **/
  public String toString()
  {
    return "BDFish " + super.toString();
  }

  // modifier method

  // (was originally a check for aliveness and a simple call to move)
  /** Acts for one step in the simulation.
   **/
  public void act()
  {
    // Make sure fish is alive and well in the environment -- fish
    // that have been removed from the environment shouldn't act.
    if ( ! isInEnv() )
      return;

    // Try to breed.
    if ( ! breed() )
      // Did not breed, so try to move.
      move();

    // Determine whether this fish will die in this timestep.
    Random randNumGen = RandNumGenerator.getInstance();
    if ( randNumGen.nextDouble() < probOfDying )
      die();
    // uncomment the following line of code to increase probability
    // of dying as fish ages
    //probOfDying += 0.1;
  }

  // helper methods

  /** Attempts to breed into neighboring locations.
   *  @return	<code>true</code> if fish successfully breeds;
   *  		<code>false</code> otherwise
   **/
  protected boolean breed()
  {
    // Determine whether this fish will try to breed in this
    // timestep. If not, return immediately.
    Random randNumGen = RandNumGenerator.getInstance();
    if ( randNumGen.nextDouble() >= probOfBreeding )
      return false;

    // Get list of neighboring empty locations.
    ArrayList emptyNbrs = emptyNeighbors();
    Debug.print(toString() + " attempting to breed. ");
    Debug.println("Has neighboring locations: " + emptyNbrs.toString());

    // If there is nowhere to breed, then we're done.
    if ( emptyNbrs.size() == 0 )
    {
      Debug.println(" Did not breed.");
      return false;
    }

    // Breed to all of the empty neighboring locations.
    for ( int index = 0; index < emptyNbrs.size(); index++ )
    {
      Location loc = (Location) emptyNbrs.get(index);
      generateChild(loc);
    }
    return true;
  }

  /** Creates a new fish with the color of its parent.
   *  @param loc	location of the new fish
   **/
  protected void generateChild(Location loc)
  {
    // Create new fish, which adds itself to the environment.
    BDFish child = new BDFish(environment(), loc,
                              environment().randomDirection(), color());
    Debug.println(" Newly created: " + child.toString());
  }

  /** Removes this fish from the environment.
   **/
  protected void die()
  {
    Debug.println(toString() + " about to die ");
    environment().remove(this);
  }
}