package speiger.src.collections.PACKAGE.queues;

#if TYPE_OBJECT
import java.util.Comparator;
#else
import speiger.src.collections.PACKAGE.collections.ITERABLE;
import speiger.src.collections.PACKAGE.functions.COMPARATOR;
import speiger.src.collections.objects.queues.ObjectPriorityQueue;
#endif

/**
 * A Simple PriorityQueue (or Queue) interface that provides with the nessesary functions to interact with it, without cluttering with the Collection interface.
 * @Type(T)
 */
#if TYPE_OBJECT
public interface PRIORITY_QUEUE KEY_GENERIC_TYPE extends Iterable<KEY_TYPE>
#else
public interface PRIORITY_QUEUE KEY_GENERIC_TYPE extends ObjectPriorityQueue<CLASS_TYPE>, ITERABLE KEY_GENERIC_TYPE
#endif
{
#if TYPE_OBJECT
	/**
	 * @return true if the PriorityQueue is empty
	 */
	public default boolean isEmpty() { return size() <= 0; }
	/**
	 * @return the amount of elements that are stored in the PriorityQueue
	 */
	public int size();
	/**
	 * clears all elements within the PriorityQueue,
	 * this does not resize the backing arrays
	 */
	public void clear();
	
#endif
	/**
	 * Method to insert a element into the PriorityQueue
	 * @param e the element that should be inserted
	 */
	public void enqueue(KEY_TYPE e);
	/**
	 * Method to extract a element from the PriorityQueue
	 * @return a element from the Queue
	 * @throws java.util.NoSuchElementException if no element is present
	 */
	public KEY_TYPE DEQUEUE();
	
	/**
	 * Peeking function to see whats inside the queue.
	 * @param index of the element that is requested to be viewed.
	 * @return the element that is requested
	 */
	public KEY_TYPE PEEK(int index);
	/**
	 * Shows the element that is to be returned next
	 * @return the first element in the Queue
	 */
	public default KEY_TYPE FIRST_KEY() { return PEEK(0); }
	
	/**
	 * Removes the first found element in the queue
	 * @param e the element that should be removed
	 * @return if a searched element was removed
	 */
	public boolean remove(KEY_TYPE e);
	/**
	 * Removes the last found element in the queue
	 * @param e the element that should be removed
	 * @return if a searched element was removed
	 */
	public boolean removeLast(KEY_TYPE e);
	
	/**
	 * Allows to notify the Queue to be revalidate its data
	 */
	public void onChanged();
	
	/**
	 * @return the sorter of the Queue, can be null
	 */
	@PrimitiveOverride
	public COMPARATOR KEY_SUPER_GENERIC_TYPE comparator();
	
	/**
	 * A method to drop the contents of the Queue without clearing the queue
	 * @return the contents of the queue into a seperate array.
	 */
	public default KEY_TYPE[] TO_ARRAY() { return TO_ARRAY(NEW_KEY_ARRAY(size())); }
	/**
	 * A method to drop the contents of the Queue without clearing the queue
	 * @param input where the elements should be inserted to. If it does not fit then it creates a new appropiatly created array
	 * @return the contents of the queue into a seperate array.
	 * @note if the Type is generic then a Object Array is created instead of a Type Array
	 */
	public KEY_TYPE[] TO_ARRAY(KEY_TYPE[] input);
	
#if !TYPE_OBJECT
	@Deprecated
	public default void enqueue(CLASS_TYPE e) { enqueue(OBJ_TO_KEY(e)); }
	@Deprecated
	public default CLASS_TYPE dequeue() { return KEY_TO_OBJ(DEQUEUE()); }
	
	@Deprecated
	public default CLASS_TYPE peek(int index) { return KEY_TO_OBJ(PEEK(index)); }
	@Deprecated
	public default CLASS_TYPE first() { return peek(0); }
	
	@Deprecated
	public default boolean remove(CLASS_TYPE e) { return remove(OBJ_TO_KEY(e)); }
	@Deprecated
	public default boolean removeLast(CLASS_TYPE e) { return removeLast(OBJ_TO_KEY(e)); }
	
	@Deprecated
	public default CLASS_TYPE[] toArray() { return toArray(new CLASS_TYPE[size()]); }
	@Deprecated
	public CLASS_TYPE[] toArray(CLASS_TYPE[] input);
	
#endif
}