/*
    * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> and others
    *
    * This program and the accompanying materials are made available under the
    * terms of the Eclipse Distribution License v. 1.0 which is available at
    * https://www.eclipse.org/org/documents/edl-v10.php.
    *
    * SPDX-License-Identifier: BSD-3-Clause
    */
  
  package org.eclipse.jgit.revwalk;
  
  import java.util.AbstractSet;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Iterator;
  import java.util.List;
  
  /**
   * Multiple application level mark bits for
   * {@link org.eclipse.jgit.revwalk.RevObject}s.
   *
   * @see RevFlag
   */
  public class RevFlagSet extends AbstractSet<RevFlag> {
  	int mask;
  
  	private final List<RevFlag> active;
  
  	/**
  	 * Create an empty set of flags.
  	 */
  	public RevFlagSet() {
  		active = new ArrayList<>();
  	}
  
  	/**
  	 * Create a set of flags, copied from an existing set.
  	 *
  	 * @param s
  	 *            the set to copy flags from.
  	 */
  	public RevFlagSethref="../../../../org/eclipse/jgit/revwalk/RevFlagSet.html#RevFlagSet">RevFlagSet(RevFlagSet s) {
  		mask = s.mask;
  		active = new ArrayList<>(s.active);
  	}
  
  	/**
  	 * Create a set of flags, copied from an existing collection.
  	 *
  	 * @param s
  	 *            the collection to copy flags from.
  	 */
  	public RevFlagSet(Collection<RevFlag> s) {
  		this();
  		addAll(s);
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public boolean contains(Object o) {
  		if (o instanceof RevFlag)
  			return (mask & ((RevFlag) o).mask) != 0;
  		return false;
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public boolean containsAll(Collection<?> c) {
  		if (c instanceof RevFlagSet) {
  			final int cMask = ((RevFlagSet) c).mask;
  			return (mask & cMask) == cMask;
  		}
  		return super.containsAll(c);
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public boolean add(RevFlag flag) {
  		if ((mask & flag.mask) != 0)
  			return false;
  		mask |= flag.mask;
  		int p = 0;
  		while (p < active.size() && active.get(p).mask < flag.mask)
  			p++;
  		active.add(p, flag);
  		return true;
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public boolean remove(Object o) {
  		final RevFlag"../../../../org/eclipse/jgit/revwalk/RevFlag.html#RevFlag">RevFlag flag = (RevFlag) o;
  		if ((mask & flag.mask) == 0)
  			return false;
  		mask &= ~flag.mask;
  		for (int i = 0; i < active.size(); i++)
  			if (active.get(i).mask == flag.mask)
  				active.remove(i);
 		return true;
 	}
 
 	/** {@inheritDoc} */
 	@Override
 	public Iterator<RevFlag> iterator() {
 		final Iterator<RevFlag> i = active.iterator();
 		return new Iterator<RevFlag>() {
 			private RevFlag current;
 
 			@Override
 			public boolean hasNext() {
 				return i.hasNext();
 			}
 
 			@Override
 			public RevFlag next() {
 				return current = i.next();
 			}
 
 			@Override
 			public void remove() {
 				mask &= ~current.mask;
 				i.remove();
 			}
 		};
 	}
 
 	/** {@inheritDoc} */
 	@Override
 	public int size() {
 		return active.size();
 	}
 }