/**
 * Title: Pancet<p>
 *
 * Description: This is part of Pancet, a game applet.  It 
 * encapsulates a single move within the move tree stored in the
 * move library.  This includes linkage values and the value
 * flipped, which represents it's value to the move tree.<p>
 *
 * Copyright: Bongo Technologies (c) 2005<p>
 *
 * @author Mark Bondurant
 * @version 3.0
 */

class Move implements GameConstants {

    private boolean flipped = false;
    private int[] parent = new int[4];
    private int move;

   /**
    * This converts play area configurations into key values
    * that can be used to index into the move library.
    */
    static String key(int[] b) {
        String k = String.valueOf(b[BOWL_A] * 1000 + b[BOWL_B] * 100 +
                                  b[BOWL_C] * 10 + b[BOWL_D]);
        while (k.length() < 4) k = "0" + k;
        return k;
    }

   /**
    * This creates a new, untried move object.
    */
    Move(int[] b, int mv) {
        for (int i=0; i<4; i++) parent[i] = b[i];
        move = mv;
    }

   /**
    * This creates a new tried move object.  This is one that will
    * be discarded at the first sign of failure.  Moves of this sort
    * are usually forced moves where this only a single option to 
    * choose from.
    */
    Move(int[] b, int mv, boolean f) {
        for (int i=0; i<4; i++) parent[i] = b[i];
        move = mv;
        flipped = f;
    }

   /**
    * This is left in because it has proven useful in debugging.
    */
    public String toString() {
        return "parent=" + this.parent_key()
                + " move=" + this.move() + " flipped=" + this.flipped();
    }

    String parent_key() {
        return key(parent);
    }

    boolean flipped() {
        return flipped;
    }

    int move() {
        return move;
    }

    void move(int m) {
        move = m;
    }

   /**
    * Most moves have two possibilities.  Once one has been proven
    * to fail, the move object is flipped to force the second possibility
    * to be tried.
    */
    void flip() {
        move = (move == BOWL_A) ? BOWL_B : BOWL_A;
        flipped = true;
    }
}