/* Copyright (c) 2005 Stanford University and Christopher Bruns
 * 
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including 
 * without limitation the rights to use, copy, modify, merge, publish, 
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject
 * to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included 
 * in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * Created on Apr 28, 2006
 * Original author: Christopher Bruns
 */
package org.simtk.chem;

import java.util.*;

public class RangeSecondaryStructure implements SecondaryStructure {
    private Residue startResidue;
    private Residue endResidue;
    
    public RangeSecondaryStructure(Residue start, Residue end) {
        this.startResidue = start;
        this.endResidue = end;
    }
    
    public Iterator<Residue> iterator() {
        return new ResRangeIterator(startResidue, endResidue);
    }
    
    class ResRangeIterator implements Iterator<Residue> {
        private Residue end;
        private Residue nextResidue, currentResidue;
        
        public ResRangeIterator(Residue start, Residue end) {
            this.end = end;

            this.nextResidue = start;
            this.currentResidue = null;
        }
        
        public boolean hasNext() {
            if (nextResidue == null) return false;
            else if (end.equals(currentResidue)) return false;
            else return true;
        }
        public Residue next() {
            if (!hasNext()) return null;
            currentResidue = nextResidue;
            nextResidue = nextResidue.getNextResidue();
            return currentResidue;
        }
        public void remove() {throw new UnsupportedOperationException();}
    }
}