package dk.itu.oop.lecture5;

public class WordExtractor implements OOPIterator {
	private OOPIterator in;
	private String word;
	/* word is either null, indicating iterator is empty, or word is head.
	 * in is positionen at the beginning of the next word to become head.
	 */

	public WordExtractor(OOPIterator in){
		this.in = in;
		extractWord();
	}

	/* pre: none
	 * post: inv.
	 */
	private void extractWord(){
		if (!in.hasNext() ){
			word = null;
			return;
		}

		StringBuffer b = new StringBuffer();
		char c = ( (Character)in.next() ).charValue();
		while ( in.hasNext() && c != '.' ){
			b.append( c );
			c = ( (Character)in.next() ).charValue();
		}
		word = b.toString();
	}

	public boolean hasNext(){ return word != null; }

	public Object peek(){ return word; }

	public Object next(){
		Object o = peek();
		extractWord();
		return o;
	}

	public OOPIterator cloneMe(){
		try{
			WordExtractor clone = (WordExtractor)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 WordExtractor(
				new CompactNonLetters(
					new CharacterIterator( haddock ) ) );
		while (itr.hasNext())
			System.out.println( itr.next() );
	}

}