package eva2.server.go.individuals.codings.ga;

import java.util.BitSet;

/** This is a gray coding for integers, sorry no variable number of bits here.
 * Created by IntelliJ IDEA.
 * User: streiche
 * Date: 24.03.2003
 * Time: 18:40:03
 * To change this template use Options | File Templates.
 */
public class GAGrayCodingInteger implements InterfaceGAIntegerCoding,java.io.Serializable {

    GAStandardCodingInteger     m_HelpingHand = new GAStandardCodingInteger();

    /** This method decodes a part of a given BitSet into a int value. This method may change the contens
     * of the BitSet if it doesn't describe a valid value.
     * The method checks wether or not the value is within the given range.
     * @param refBitSet             The BitSet where the integer value is stored.
     * @param range                 The allowed range of the value.
     * @param locus                 The position and length on the BitSet that is to be decoded.
     * @param correction            Enable automatic correction is enabled.
     * @return The int value.
     */
    @Override
    public int decodeValue(BitSet refBitSet, int[] range, int[] locus, boolean correction) {
        BitSet              tmpBitSet;
        int[]               tmpLocus;
        boolean             tmpB = false;

        tmpLocus        = new int[2];
        tmpLocus[0]     = 0;
        tmpLocus[1]     = locus[1];
        tmpBitSet       = new BitSet(tmpLocus.length);

//        for (int i = 0; i < tmpLocus.length; i++) {
//            tmpB = (tmpB ^ refBitSet.get(locus[1] + i));
//            if (tmpB) tmpBitSet.set(i);
//            else tmpBitSet.clear(i);
//        }
        for (int i = 0; i < tmpLocus[1]; i++) {
            tmpB = refBitSet.get(locus[0]);
            for (int j = 1; j <= i; j++) tmpB = tmpB ^ refBitSet.get(locus[0] + j);
            if (tmpB) tmpBitSet.set(i);
            else tmpBitSet.clear(i);
        }
        return this.m_HelpingHand.decodeValue(tmpBitSet, range, tmpLocus, correction);
    }

    /** This method codes a given int value directly into a BitSet at
     * the position which is specified by locus.
     * The method checks wether or not the value is within the given range.
     * @param value             The value to be coded.
     * @param range             The allowed range of the value.
     * @param refBitSet         The BitSet where the questioned value is stored.
     * @param locus             The position and length on the BitSet that is to be coded.
     */
    @Override
    public void codeValue(int value, int[] range, BitSet refBitSet, int[] locus) {
        BitSet              tmpBitSet;
        int[]               tmpLocus;

        tmpLocus        = new int[2];
        tmpLocus[0]     = 0;
        tmpLocus[1]     = locus[1];
        tmpBitSet       = new BitSet(tmpLocus.length);
        this.m_HelpingHand.codeValue(value, range, tmpBitSet, tmpLocus);

//        if (tmpBitSet.get(0)) refBitSet.set(locus[1]);
//        else refBitSet.clear(locus[1]);
//        for (int i = 1; i < locus.length; i++) {
//            if (tmpBitSet.get(i)^tmpBitSet.get(i-1)) refBitSet.set(locus[1] + i);
//            else refBitSet.clear(locus[1] + i);
//        }
        if (tmpBitSet.get(0)) refBitSet.set(locus[0]);
        else refBitSet.clear(locus[0]);
        for (int i = 1; i < locus[1]; i++) {
            if (tmpBitSet.get(i)^tmpBitSet.get(i-1)) refBitSet.set(locus[0] + i);
            else refBitSet.clear(locus[0] + i);
        }
    }
    
    /** This method will calculate how many bits are to be used to code a given value
     * @param range     The range for the value.
     */
    @Override
    public int calculateNecessaryBits(int[] range) {
        return this.m_HelpingHand.calculateNecessaryBits(range);
    }

    /** Perhaps a special output is necessary.
     * @param b    The BitString.
     * @return          A printable String.
     */
    public String printBitSet(BitSet b) {
        return this.printBitSet(b, b.size());
    }

    /** Perhaps a special output is necessary.
     * @param b    The BitString.
     * @return          A printable String.
     */
    public String printBitSet(BitSet b, int length) {
        String  output = "{";

        for (int i = 0; i < length; i++) {
            if (b.get(i)) output += "1";
            else output += "0";
        }
        output += "}\n";
        return output;
    }
}