/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is the Application Update Service
 *
 * The Initial Developer of the Original Code is Google Inc.
 * Portions created by the Initial Developer are Copyright (C) 2005
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *  Ben Goodger <ben@mozilla.org>
 *  Benjamin Smedberg <benjamin@smedbergs.us>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#include "nsISupports.idl"

/**
 * Version strings are dot-separated sequences of version-parts.
 *
 * A version-part consists of up to four parts, all of which are optional:
 *
 * <number-a><string-b><number-c><string-d (everything else)>
 *
 * A version-part may also consist of a single asterisk "*" which indicates
 * "infinity".
 *
 * Numbers are base-10, and are zero if left out.
 * Strings are compared bytewise.
 *
 * For additional backwards compatibility, if "string-b" is "+" then
 * "number-a" is incremented by 1 and "string-b" becomes "pre".
 *
 * 1.0pre1
 * < 1.0pre2  
 *   < 1.0 == 1.0.0 == 1.0.0.0
 *     < 1.1pre == 1.1pre0 == 1.0+
 *       < 1.1pre1a
 *         < 1.1pre1
 *           < 1.1pre10a
 *             < 1.1pre10
 *
 * Although not required by this interface, it is recommended that
 * numbers remain within the limits of a signed char, i.e. -127 to 128.
 */
[scriptable, uuid(e6cd620a-edbb-41d2-9e42-9a2ffc8107f3)]
interface nsIVersionComparator : nsISupports
{
  /**
   * Compare two version strings
   * @param   A   The first version
   * @param   B   The second version
   * @returns < 0 if A < B
   *          = 0 if A == B
   *          > 0 if A > B
   */
  long compare(in ACString A, in ACString B);
};