package utility.merge;

import exceptions.BoundaryViolationException;
import exceptions.EmptyListException;
import exceptions.InvalidPositionException;
import position.NodePositionList;
import position.Position;
import position.PositionList;
import utility.DefaultComparator;

import java.util.Comparator;
import java.util.Iterator;

/**
 * Created with xgiovio.macbookair.
 * User: xgiovio
 * Date: 14/05/14
 * Time: 14:48
 */
public abstract class MergeTemplate<E> {

    protected PositionList<E> s = new NodePositionList<E>();
    protected Comparator<E> c = null;

    public MergeTemplate (PositionList<E> A, PositionList <E> B){
            this(A,B,new DefaultComparator<E>());
    }

    public MergeTemplate (PositionList<E> A, PositionList <E> B, Comparator<E> in_c){

        c = in_c;
        E a = null ,b = null;
        Iterator<E> Ait, Bit;
        Ait = A.iterator();
        Bit = B.iterator();


        if ( Ait.hasNext() && Bit.hasNext() ){
            a = Ait.next();
            b = Bit.next();
            for (; true; ) {

                if (c.compare(a, b) < 0) {
                    aIsLess(a);
                    if (Ait.hasNext())
                        a = Ait.next();
                    else
                        break;
                } else {
                    if (c.compare(a, b) > 0) {
                        bIsLess(b);
                        if (Bit.hasNext())
                            b = Bit.next();
                        else
                            break;

                    } else {// se b = a
                        bothAreEqual(a, b);
                        if (Ait.hasNext() && Bit.hasNext()) {
                            a = Ait.next();
                            b = Bit.next();
                        } else
                            break;

                    }
                }

            }
        }
        while ( Ait.hasNext() ) {
            a = Ait.next();
            aIsLess(a);
        }
        while ( Bit.hasNext()) {
            b = Bit.next();
            bIsLess(b);
        }


    }


    abstract protected void aIsLess (E a);

    abstract protected void bIsLess (E b);

    abstract protected void bothAreEqual (E a, E b);


    public PositionList<E> getResult () {
        return s;
    }







}