package li.earth.urchin.twic.collections;

import java.util.Collection;
import java.util.List;
import java.util.ListIterator;
import java.util.AbstractList;

public class GeneralBigSubList<E> extends AbstractBigList<E> {
	
	private final BigList<E> list;
	private final long base;
	private long size;
	
	public GeneralBigSubList(BigList<E> list, long fromIndex, long toIndex) {
		if (fromIndex < 0L) throw new IndexOutOfBoundsException("illegal fromIndex value: " + fromIndex);
		if ((toIndex > list.bigSize()) || (fromIndex > toIndex)) throw new IndexOutOfBoundsException("illegal toIndex value: " + toIndex);
		this.list = list;
		base = fromIndex;
		size = toIndex - fromIndex;
	}
	
	public long bigSize() {
		return size;
	}
	
	public E get(long index) {
		boundsCheck(index, false);
		return list.get(index + base);
	}
	
	public E set(long index, E obj) {
		boundsCheck(index, false);
		return list.set((index + base), obj);
	}
	
	public void add(long index, E obj) {
		boundsCheck(index, true);
		list.set((index + base), obj);
		++size;
	}
	
	public E remove(long index) {
		boundsCheck(index, false);
		E obj = list.remove((index + base));
		--size;
		return obj;
	}
	
	private void boundsCheck(long index, boolean halfOpen) {
		if ((index < 0L) || (halfOpen ? (index > size) : (index >= size))) throw new IndexOutOfBoundsException(Long.toString(index));
	}
	
}