import java.awt.*;
import java.util.*;
/**
 * This class represents a hungry fish that eats
 * other fish
 * 
 */
public class HungryFish extends Fish
{
  ////////// fields /////////////////////////////
  
  /** how hungry this fish is */
  private int hunger = 0; // start off not hungry
  private static final int NEED_TO_EAT = 5; // how hungry
  
  /////////////// Constructors //////////////////
  
  /**
   * Constructor that takes an environment and a location
   * @param env the environment that this fish is in
   * @param loc the location (row,col) that this fish is in
   */
  public HungryFish(Environment env, Location loc)
  {
    // Construct and initialize the attributes inherited from Fish.
    super(env, loc, env.randomDirection(), Color.black);
  }
  
  /**
   * Constructor that takes the environment, location, and direction
   * @param env the environment that this fish is in
   * @param loc the location (row,col) that this fish is in
   * @param dir the direction the fish is facing
   */
  public HungryFish(Environment env, Location loc, Direction dir)
  {
    super(env,loc,dir, Color.black);
  }
  
   public HungryFish(Environment env, Location loc, Direction dir, Color col)
    {
        // Construct and initialize the attributes inherited from Fish.
        super(env, loc, dir, col);
   }
   
   /** Creates a new hungry fish.
     *  @param loc    location of the new fish
     **/
    protected void generateChild(Location loc)
    {
        // Create new fish, which adds itself to the environment.
        HungryFish child = new HungryFish(environment(), loc,
                                      environment().randomDirection(),
                                      color());
        Debug.println("  New HungryFish created: " + child.toString());
    }
    
    /**
     * Method to do the action during a timestep
     */
    public void act()
    {
      // only act if still in the environment
      if (isInEnv())
      {
        // increment the hunger
        hunger = hunger + 1;
        
        // get a list of locations with neighboring fish
        java.util.List neighbors = fullFishNeighbors();
        
        // first see if hungry and have neighbors
        if (hunger >= NEED_TO_EAT && neighbors.size() > 0)
        {
          // eat a random neighbor
          Random randNumGen = RandNumGenerator.getInstance();
          Location loc = (Location) neighbors.get(randNumGen.nextInt(neighbors.size()));
          Fish neighbor = (Fish) environment().objectAt(loc);
          neighbor.die();
          hunger = 0; // reset hunger
          Debug.println("Fish " + this + " eating fish at " + loc);
          
          // Move to eaten fish location.
          Location oldLoc = location();
          changeLocation(loc);
          
          // Update direction in case fish had to turn to move.
          Direction newDir = environment().getDirection(oldLoc, loc);
          changeDirection(newDir);
        }
        
        // else move like a normal fish
        else 
        {
          Debug.println("Fish " + this + 
            "is not hungry or doesn't have any neighboring fish to eat");
          move();
        }
      }
      
    }
  
}