Mass Private Messaging?

<?php
/***********************************************************************

  Copyright (C) 2007  guardian34 (punbb@fmguy.com)

  This file is part of PunBB.

  PunBB 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; either version 2 of the License,
  or (at your option) any later version.

  PunBB 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, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  MA  02111-1307  USA

************************************************************************/


// Make sure no one attempts to run this script "directly"
if (!defined('PUN'))
    exit;

// Tell admin_loader.php that this is indeed a plugin and that it is loaded
define('PUN_PLUGIN_LOADED', 1);

// Load the language files
require_once PUN_ROOT.'lang/'.$pun_user['language'].'/pms.php';
require_once PUN_ROOT.'lang/'.$pun_user['language'].'/post.php';


if (isset($_POST['send']))
{
    $group = intval($_POST['group']);
    $subject = pun_trim($_POST['subject']);
    $message = pun_linebreaks(pun_trim($_POST['message']));
    $hide_smilies = (isset($_POST['hide_smilies'])) ? 1 : 0;

    // Check group
    if ($group < 0 || $group == 3)
        message('You didn\'t specify a valid group!');

    // Check subject
    if ($subject == '')
        message($lang_post['No subject']);
    else if (pun_strlen($subject) > 70)
        message($lang_post['Too long subject']);

    // Check message
    if ($message == '')
        message($lang_post['No message']);
    else if (strlen($message) > 65535)
        message($lang_post['Too long message']);

    // Validate BBCode syntax
    if ($pun_config['p_message_bbcode'] == '1' && strpos($message, '[') !== false && strpos($message, ']') !== false)
    {
        require PUN_ROOT.'include/parser.php';
        $message = preparse_bbcode($message, $errors);
    }
    if (isset($errors))
        message($errors[0]);


    // Get group members
    $where_sql = ($group != 0) ? 'group_id='.$group : 'id!=1';
    $result = $db->query('SELECT id, username FROM '.$db->prefix.'users WHERE '.$where_sql) or error('Unable to fetch group members', __FILE__, __LINE__, $db->error());
    if ($db->num_rows($result) == 0)
        message('No members found for group '.$group.'.');

    // Save a copy of the message for the sender
    if(isset($_POST['save_message']))
    {
        $db->query('INSERT INTO '.$db->prefix.'messages (owner, subject, message, sender, sender_id, sender_ip, smileys, showed, status, posted) VALUES(
            \''.$pun_user['id'].'\',
            \''.$db->escape($subject).'\',
            \''.$db->escape($message).'\',
            \''.$db->escape($user).'\',
            \''.$pun_user['id'].'\',
            \''.get_remote_address().'\',
            \''.$hide_smilies.'\',
            \'1\',
            \'1\',
            \''.time().'\'
        )') or error('Unable to save message', __FILE__, __LINE__, $db->error());
    }

    // Send messages
    while ($cur_user = $db->fetch_assoc($result))
    {
        $db->query('INSERT INTO '.$db->prefix.'messages (owner, subject, message, sender, sender_id, sender_ip, smileys, showed, status, posted) VALUES(
            \''.$cur_user['id'].'\',
            \''.$db->escape($subject).'\',
            \''.$db->escape($message).'\',
            \''.$db->escape($pun_user['username']).'\',
            \''.$pun_user['id'].'\',
            \''.get_remote_address().'\',
            \''.$hide_smilies.'\',
            \'0\',
            \'0\',
            \''.time().'\'
        )') or error('Unable to send message', __FILE__, __LINE__, $db->error());
    }

    redirect($_SERVER['REQUEST_URI'], 'Private messages sent');
}


// Display the admin navigation menu
generate_admin_menu($plugin);

?>
    <div class="block">
        <h2><span>Mass Private Message - v1.0</span></h2>
        <div class="box">
            <div class="inbox">
                <form method="post" action="<?php echo $_SERVER['REQUEST_URI'] ?>">
                    <p>This plugin "sends" private messages to a group of users. (<em>Note:</em> Private message mod is required.)</p>
                </form>
            </div>
        </div>
    </div>

    <div class="blockform">
        <h2 class="block2"><span>Mass Private Message</span></h2>
        <div class="box">
            <form method="post" action="<?php echo $_SERVER['REQUEST_URI'] ?>">
                <div class="inform">
                    <fieldset>
                        <legend>Message</legend>
                        <div class="infldset">
                            <label><strong><?php echo $lang_pms['Send to'] ?></strong><br />
                                <select name="group">
                                    <option value="0" selected="selected">** All Users</option>
<?php
                                    // Get admin and moderator groups
                                    $result = $db->query('SELECT g_id, g_title FROM '.$db->prefix.'groups WHERE g_id<'.PUN_GUEST.' ORDER BY g_id') or error('Unable to fetch user group list', __FILE__, __LINE__, $db->error());                                    

                                    while ($cur_group = $db->fetch_assoc($result))
                                        echo "\t\t\t\t\t\t\t\t\t".'<option value="'.$cur_group['g_id'].'">'.pun_htmlspecialchars($cur_group['g_title']).'</option>'."\n";

                                    // Get other groups
                                    $result = $db->query('SELECT g_id, g_title FROM '.$db->prefix.'groups WHERE g_id>'.PUN_GUEST.' ORDER BY g_title') or error('Unable to fetch user group list', __FILE__, __LINE__, $db->error());

                                    while ($cur_group = $db->fetch_assoc($result))
                                        echo "\t\t\t\t\t\t\t\t\t".'<option value="'.$cur_group['g_id'].'">'.pun_htmlspecialchars($cur_group['g_title']).'</option>'."\n";

?>                                </select><br />
                            </label>
                            
                            <label><strong><?php echo $lang_common['Subject'] ?></strong><br />
                            <input class="longinput" type="text" name="subject" value="" size="80" maxlength="70" style="width: 100%;" /><br /></label>
                            
                            <?php //require PUN_ROOT.'mod_easy_bbcode.php' ?>
                            
                            <label><strong><?php echo $lang_common['Message'] ?></strong><br />
                            <textarea name="message" rows="18" cols="95" style="width: 100%;"></textarea></label>
                            
                            <ul class="bblinks">
                                <li><a href="help.php#bbcode" onclick="window.open(this.href); return false;"><?php echo $lang_common['BBCode'] ?></a>: <?php echo ($pun_config['p_message_bbcode'] == '1') ? $lang_common['on'] : $lang_common['off']; ?></li>
                                <li><a href="help.php#img" onclick="window.open(this.href); return false;"><?php echo $lang_common['img tag'] ?></a>: <?php echo ($pun_config['p_message_img_tag'] == '1') ? $lang_common['on'] : $lang_common['off']; ?></li>
                                <li><a href="help.php#smilies" onclick="window.open(this.href); return false;"><?php echo $lang_common['Smilies'] ?></a>: <?php echo ($pun_config['o_smilies'] == '1') ? $lang_common['on'] : $lang_common['off']; ?></li>
                            </ul>
                        </div>
                    </fieldset>
                </div>
<?php
    $checkboxes = array();

    if ($pun_config['o_smilies'] == '1')
        $checkboxes[] = '<label><input type="checkbox" name="hide_smilies" value="1" />'.$lang_post['Hide smilies'];

    $checkboxes[] = '<label><input type="checkbox" name="save_message" value="1" />'.$lang_pms['Save message']; 

    if (!empty($checkboxes))
    {
?>                <div class="inform">
                     <fieldset>
                        <legend>Options</legend>
                        <div class="infldset">
                            <div class="infldset">
                                <div class="rbox">
                                    <?php echo implode('<br /></label>'."\n\t\t\t\t", $checkboxes).'<br /></label>'."\n" ?>
                                </div>
                            </div>
                        </div>
                    </fieldset>
                 </div>
<?php
    }
?>                <p class="submitend"><input type="submit" name="send" value="<?php echo $lang_pms['Send'] ?>" /></p>
            </form>
        </div>
    </div>