package ac.essex.gp.nodes.meta;

import ac.essex.gp.params.NodeParams;
import ac.essex.gp.params.RangeTypes;
import ac.essex.gp.util.DataStack;
import ac.essex.gp.nodes.ercs.BasicERC;

/**
 * <p/>
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version,
 * provided that any use properly credits the author.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details at http://www.gnu.org
 * </p>
 *
 * @author Olly Oechsle, University of Essex, Date: 18-Jan-2007
 * @version 1.0
 */
public abstract class MetaERC extends BasicERC {

    protected double value;

    public MetaERC() {
        super();
        this.value = setValue();
    }

    // START ERC METHODS
    public void mutate() {
        this.value = setValue();
    }

    public void jitter() {
        // jitter within 30% of the value
        double amount = 0.3;
        double change = 1.0 + (Math.random() * amount * 2);
        value = (int) (value * change);
    }
    // END ERC METHODS

    public int getReturnType() {
        return NodeParams.VOID;
    }

    public abstract double execute(DataStack data);

    public abstract String toJava();

    public int getChildType(int index) {
        return NodeParams.VOID;
    }

    public boolean isOptimisable() {
        return false;
    }

    public int getRangeID() {
        return RangeTypes.DONT_CARE;
    }
    
}