/**
 * Copyright (C) 2022 by Martin Robillard. See https://codesample.info/about.html
 */
package e2.chapter6;

/**
 * Represents an entity from which it is possible to obtain cards.
 * This version can be polymorphically copied.
 */
public interface CardSource
{
	/**
	 * Returns a card from the source.
	 *
	 * @return The next available card.
	 * @pre !isEmpty()
	 */
	Card draw();
	
	/**
	 * @return True if there is no card in the source.
	 */
	boolean isEmpty();
	
	/**
	 * @return A card source that is a deep copy (distinct object graph)
	 * of this card source.
	 */
	CardSource copy();
}