<?php
# Copyright(C) 2004-2007 INL
# Written by Eric Leblond <regit@inl.fr>
#            Vincent Deffontaines <gryzor@inl.fr>
#            Jean Gillaux <jean@inl.fr>
#            Damien Boucard <damien.boucard AT inl.fr>
#
# $Id: set.class.php 17927 2009-02-16 13:16:09Z haypo $
#
# This program 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 3 of the License.
#
#  This program 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 this program; if not, see <http://www.gnu.org/licenses/>.

require_once('function.php'); // modifiedTimestamp()

class set
{
    var $elts;

    function add_elt($elt, $id=null)
    {
        if (is_null($id)) {
            $id = $elt->get_id();
        }
        $this->_check_new_element($elt, $id);
        if (array_key_exists($id, $this->elts)) {
            throw new Exception(sprintf(_('Duplicate identifier (%s)!'), $id));
        }
        $this->elts[$id] = $elt;
    }

    function replace_elt($elt, $id=null)
    {
        if (is_null($id)) {
            $id = $elt->get_id();
        }
        if (array_key_exists($id, $this->elts)) {
            $old_elt = $this->elts[$id];
            unset ($this->elts[$id]);
        } else {
            $old_elt = null;
        }
        try {
            // Try to add the new element
            $this->add_elt($elt, $id);
        } catch (Exception $err) {
            // On error: restore previous element
            $this->elts[$id] = $old_elt;
            throw $err;
        }
    }

    function _check_new_element($elt, $id)
    {
        if (array_key_exists($id, $this->elts)) {
            throw new Exception(sprintf(_('Duplicate identifier (%s)!'), $id));
        }
    }

    function has_elt($elt)
    {
        return array_key_exists($elt, $this->elts);
    }

    function get_elt($elt){
        if (array_key_exists($elt, $this->elts))
            return $this->elts[$elt];
        else
            return null;
    }

    function del_elt($index)
    {
        unset ($this->elts[$index]);
    }
}

?>