package dk.itu.oop.lecture5;

public class CNL implements OOPIterator {
	private OOPIterator in;
	private char head;
	// if packed, then head is ".", else head is in.head

	public CNL(OOPIterator in){
		this.in = in;
		setHead();
	}


	private void setHead(){
		if ( in.hasNext() )
			if ( !isLetter()){
				head ='.';
				while (in.hasNext() && !isLetter() )
					in.next();
			} else
				head = ( (Character) in.peek() ).charValue();
		else
			head = '.';
	}

	public boolean hasNext(){ return in.hasNext() || head=='.'; }

	public Object peek(){
		return new Character( head );
	}

	public Object next(){
		Object o = peek();
		if (head !='.')
			in.next();
		setHead();
		return o;
	}

	private boolean isLetter(){
		return Character.isLetter( ( (Character) in.peek() ).charValue() );
	}

	public OOPIterator cloneMe(){
		try{
			CNL clone = (CNL)super.clone();
			clone.in = in.cloneMe();
			return clone;
		}catch(CloneNotSupportedException e){
			return null;
		}
	}

	public static void main(String[] args){
		String haddock = "You #!@ Miserable earthworms! Numbskulls! and Carpet-sellers!";
		OOPIterator itr = new CNL(new CharacterIterator( haddock ) );
		while (itr.hasNext())
			System.out.print( itr.next() );
		System.out.println();
	}

}