/*****************************************************/
/*          This java file is a part of the          */
/*                                                   */
/*           -  Plouf's Java IRC Client  -           */
/*                                                   */
/*   Copyright (C)  2002 - 2004 Philippe Detournay   */
/*                                                   */
/*         All contacts : theplouf@yahoo.com         */
/*                                                   */
/*  PJIRC is free software; you can redistribute     */
/*  it and/or modify it under the terms of the GNU   */
/*  General Public License as published by the       */
/*  Free Software Foundation; version 2 or later of  */
/*  the License.                                     */
/*                                                   */
/*  PJIRC is distributed in the hope that it will    */
/*  be useful, but WITHOUT ANY WARRANTY; without     */
/*  even the implied warranty of MERCHANTABILITY or  */
/*  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU   */
/*  General Public License for more details.         */
/*                                                   */
/*  You should have received a copy of the GNU       */
/*  General Public License along with PJIRC; if      */
/*  not, write to the Free Software Foundation,      */
/*  Inc., 59 Temple Place, Suite 330, Boston,        */
/*  MA  02111-1307  USA                              */
/*                                                   */
/*****************************************************/

package irc;

import java.util.Hashtable;
import java.util.StringTokenizer;

/**
 * Handling for unbound list of items.
 */
public class ListHandler {
	private boolean _baseAll;
	private Hashtable _list;
	private String _orig;

	/**
	 * Create a new list of items.
	 * 
	 * @param list
	 *          item list. Syntax is : "" or "none+item1+item2+item3+..." or
	 *          "all-item1-item2-item3-..." If list is empty, it is equivalent to
	 *          "all". Items containing + or - characters can be used by replacing
	 *          them by \+ or \-. The \ character may be entenred using \\ syntax.
	 */
	public ListHandler(String list) {
		_orig = list;
		list = convert(list);
		_baseAll = true;
		_list = new Hashtable();
		StringTokenizer st = new StringTokenizer(list, "\1\2", true);
		if (!st.hasMoreTokens())
			return;
		String base = st.nextToken();
		if (base.equals("none"))
			_baseAll = false;
		while (st.hasMoreTokens()) {
			String mod = st.nextToken();
			if (mod.equals("\1"))
				mod = "-";
			else if (mod.equals("\2"))
				mod = "+";
			if (!st.hasMoreTokens())
				break;
			String token = st.nextToken().toLowerCase(java.util.Locale.ENGLISH);
			_list.put(token, mod);
		}
	}

	private String convert(String txt) {
		String ans = "";
		for (int i = 0; i < txt.length(); i++) {
			char c = txt.charAt(i);
			if (c == '-')
				c = '\1';
			else if (c == '+')
				c = '\2';
			else if (c == '\\' && (i != txt.length() - 1)) {
				i++;
				c = txt.charAt(i);
			}
			ans += c;
		}
		return ans;
	}

	/**
	 * Test wether the given item is in the list.
	 * 
	 * @param item
	 *          item to check.
	 * @return true if item is in the list, false otherwise.
	 */
	public boolean inList(String item) {
		item = item.toLowerCase(java.util.Locale.ENGLISH);
		String mod = (String) _list.get(item);
		if (mod == null)
			return _baseAll;
		if (mod.equals("+"))
			return true;
		return false;
	}

	@Override
	public String toString() {
		return _orig;
	}
}