package sequence;

import exceptions.BoundaryViolationException;
import exceptions.EmptyListException;
import exceptions.EmptySequenceException;
import exceptions.InvalidPositionException;
import position.NodePositionList;
import position.Position;

/**
 * Created with MONSTER.
 * User: xgiovio
 * Date: 30/03/2014
 * Time: 14:35
 */
public class NodeSequence <E> extends NodePositionList<E> implements Sequence<E> {

    @Override
    public E getFirst() throws EmptySequenceException {
        try {
            Position<E> t = first();
            return t.element();
        }
        catch (EmptyListException e){
            throw new EmptySequenceException();
        }
    }

    @Override
    public E getLast() throws EmptySequenceException {
        try {
            Position<E> t = last();
            return t.element();
        }
        catch (EmptyListException e){
            throw new EmptySequenceException();
        }
    }

    @Override
    public E removeFirst() throws EmptySequenceException {
        try {
            Position<E> t = first();
            E ele = remove(t);
            return ele;
        }
        catch (EmptyListException e){
            throw new EmptySequenceException();
        }
    }

    @Override
    public E removeLast() throws EmptySequenceException {
        try {
            Position<E> t = last();
            E ele = remove(t);
            return ele;
        }
        catch (EmptyListException e){
            throw new EmptySequenceException();
        }
    }

    @Override // si potrebbe anche andare indietro a partire dall'ultimo
    public Position<E> atIndex(int index) throws BoundaryViolationException {
        try {
            checkIndex(index, size());
            Position<E> t = first();
            for (int i = 0; i < index; i++) {
                t = next(t);
            }
            return t;
        }
        catch (IndexOutOfBoundsException e){
            throw new BoundaryViolationException();
        }

    }

    @Override
    public int indexOf(Position<E> position) throws InvalidPositionException {
        checkPosition(position);
        Position<E> t = first();
        int i ;
        for (i = 0 ;t != position;i++){
            t= next(t);
        }
        return i;

    }

    @Override
    public E remove(int i) throws IndexOutOfBoundsException {
        checkIndex(i,size());
        E ele = remove(atIndex(i));
        return  ele;

    }

    @Override
    public void add(int i, E e) throws IndexOutOfBoundsException {
        try {
            checkIndex(i,size()+1);
            if (i == 0){
                addFirst(e);
            } else {
                if ( i== size()){
                    addLast(e);
                }else {
                    Position<E> t = atIndex(i);
                    addBefore(t, e);
                }
            }
        }
        catch (BoundaryViolationException err){
            throw new IndexOutOfBoundsException ();
        }

    }

    @Override
    public E set(int i, E e) throws IndexOutOfBoundsException {
        try {
            Position<E> t = atIndex(i);
            E ele = set(t,e);
            return ele;
        }
        catch (BoundaryViolationException err){
            throw new IndexOutOfBoundsException ();
        }
    }

    @Override
    public E get(int i) throws IndexOutOfBoundsException {
        try {
            Position<E> t = atIndex(i);
            return t.element();
        }
        catch (BoundaryViolationException err){
            throw new IndexOutOfBoundsException ();
        }
    }


    protected void checkIndex(int r, int n)  throws IndexOutOfBoundsException {
        if (r < 0 || r >= n)
            throw new IndexOutOfBoundsException("Illegal index: " + r);
    }

    @Override
    public String toString() {
        String to_return = "";
        to_return = to_return + "[";
        if (size() > 0) {
            int i;
            Position<E> temp;
            for (temp = first(), i = 0;true;) {

                if ( i == size() - 1) {
                    to_return += (temp.element().toString());
                } else {
                    to_return += (temp.element().toString() + ",");
                }
                if (i == size() - 1){
                    break;
                }else{
                   i++;
                   temp = next(temp);
                }
            }
        }
        to_return = to_return + "]";
        return to_return;
    }
}