<?php
/*
* Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
* Version 1.0 (Banshee)
* pageprocess.php - intelligent retrieval of pages
* Copyright (C) 2006-2007 Dan Fuhry
*
* This program is Free Software; you can redistribute 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.
*
* 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 details.
*/
/**
* Class to handle fetching page text (possibly from a cache) and formatting it.
* @package Enano
* @subpackage UI
* @copyright 2007 Dan Fuhry
* @license GNU General Public License <http://www.gnu.org/licenses/gpl.html>
*/
class PageProcessor
{
/**
* Page ID and namespace of the page handled by this instance
* @var string
*/
var $page_id;
var $namespace;
/**
* Tracks if the page we're loading exists in the database or not.
* @var bool
*/
var $page_exists = false;
/**
* Permissions!
* @var object
*/
var $perms = null;
/**
* Switch to track if redirects are allowed. Defaults to true.
* @var bool
*/
var $allow_redir = true;
/**
* If this is set to true, this will call the header and footer funcs on $template when render() is called.
* @var bool
*/
var $send_headers = false;
/**
* Cache the fetched text so we don't fetch it from the DB twice.
* @var string
*/
var $text_cache = '';
/**
* Debugging information to track errors. You can set enable to false to disable sending debug information.
* @var array
*/
var $debug = array(
'enable' => true,
'works' => false
);
/**
* Constructor.
* @param string The page ID (urlname) of the page
* @param string The namespace of the page
*/
function __construct( $page_id, $namespace )
{
global $db, $session, $paths, $template, $plugins; // Common objects
// See if we can get some debug info
if ( function_exists('debug_backtrace') && $this->debug['enable'] )
{
$this->debug['works'] = true;
$this->debug['backtrace'] = enano_debug_print_backtrace(true);
}
// First things first - check page existence and permissions
if ( !isset($paths->nslist[$namespace]) )
{
$this->send_error('The namespace "' . htmlspecialchars($namespace) . '" does not exist.');
}
$this->_setup( $page_id, $namespace );
}
/**
* The main method to send the page content. Also responsible for checking permissions.
*/
function send()
{
global $db, $session, $paths, $template, $plugins; // Common objects
if ( !$this->perms->get_permissions('read') )
{
$this->err_access_denied();
return false;
}
if ( $this->namespace == 'Special' || $this->namespace == 'Admin' )
{
if ( !$this->page_exists )
{
redirect( makeUrl(getConfig('main_page')), 'Can\'t find special page', 'The special or administration page you requested does not exist. You will now be transferred to the main page.', 2 );
}
$func_name = "page_{$this->namespace}_{$this->page_id}";
if ( function_exists($func_name) )
{
return @call_user_func($func_name);
}
else
{
$title = 'Page backend not found';
$message = "The administration page you are looking for was properly registered using the page API, but the backend function
(<tt>$fname</tt>) was not found. If this is a plugin page, then this is almost certainly a bug with the plugin.";
if ( $this->send_headers )
{
$template->tpl_strings['PAGE_NAME'] = $title;
$template->header();
echo "<p>$message</p>";
$template->footer();
}
else
{
echo "<h2>$title</h2>
<p>$message</p>";
}
return false;
}
}
else if ( in_array($this->namespace, array('Article', 'User', 'Project', 'Help', 'File', 'Category')) && $this->page_exists )
{
// Send as regular page
$text = $this->fetch_text();
if ( $text == 'err_no_text_rows' )
{
$this->err_no_rows();
return false;
}
else
{
$this->render();
}
}
else if ( ( $this->namespace == 'Template' || $this->namespace == 'System' ) && $this->page_exists )
{
$this->header();
$text = $this->fetch_text();
$text = preg_replace('/<noinclude>(.*?)<\/noinclude>/is', '\\1', $text);
$text = preg_replace('/<nodisplay>(.*?)<\/nodisplay>/is', '', $text);
$text = RenderMan::render( $text );
echo $text;
$this->footer();
}
else if ( !$this->page_exists )
{
// Perhaps this is hooked?
ob_start();
$code = $plugins->setHook('page_not_found');
foreach ( $code as $cmd )
{
eval($cmd);
}
$ob = ob_get_contents();
if ( empty($ob) )
{
$this->err_page_not_existent();
}
}
}
/**
* Sets internal variables.
* @access private
*/
function _setup($page_id, $namespace)
{
global $db, $session, $paths, $template, $plugins; // Common objects
$page_id_cleaned = sanitize_page_id($page_id);
$this->page_id = $page_id_cleaned;
$this->namespace = $namespace;
$this->perms = $session->fetch_page_acl( $page_id, $namespace );
// Exception for Admin: pages
if ( $this->namespace == 'Admin' )
{
$fname = "page_Admin_{$this->page_id}";
}
// Does the page "exist"?
if ( $paths->cpage['urlname_nons'] == $page_id && $paths->namespace == $namespace && !$paths->page_exists && ( $this->namespace == 'Admin' && !function_exists($fname) ) )
{
$this->page_exists = false;
}
else if ( !isset( $paths->pages[ $paths->nslist[$namespace] . $page_id ] ) && ( $this->namespace == 'Admin' && !function_exists($fname) ) )
{
$this->page_exists = false;
}
else
{
$this->page_exists = true;
}
}
/**
* Renders it all in one go, and echoes it out. This assumes that the text is in the DB.
* @access private
*/
function render()
{
$text = $this->fetch_text();
$this->header();
display_page_headers();
echo RenderMan::render($text);
display_page_footers();
$this->footer();
}
/**
* Sends the page header, dependent on, of course, whether we're supposed to.
*/
function header()
{
global $db, $session, $paths, $template, $plugins; // Common objects
if ( $this->send_headers )
$template->header();
}
/**
* Sends the page footer, dependent on, of course, whether we're supposed to.
*/
function footer()
{
global $db, $session, $paths, $template, $plugins; // Common objects
if ( $this->send_headers )
$template->footer();
}
/**
* Fetches the raw, unfiltered page text.
* @access public
*/
function fetch_text()
{
global $db, $session, $paths, $template, $plugins; // Common objects
if ( !empty($this->text_cache) )
{
return $this->text_cache;
}
$q = $db->sql_query('SELECT page_text, char_tag FROM '.table_prefix.'page_text WHERE page_id=\'' . $this->page_id . '\' AND namespace=\'' . $this->namespace . '\';');
if ( !$q )
{
$this->send_error('Error during SQL query.', true);
}
if ( $db->numrows() < 1 )
{
$this->page_exists = false;
return 'err_no_text_rows';
}
$row = $db->fetchrow();
$db->free_result();
if ( !empty($row['char_tag']) )
{
// This page text entry uses the old text-escaping format
$from = array(
"{APOS:{$row['char_tag']}}",
"{QUOT:{$row['char_tag']}}",
"{SLASH:{$row['char_tag']}}"
);
$to = array("'", '"', '\\');
$row['page_text'] = str_replace($from, $to, $row['page_text']);
}
$this->text_cache = $row['page_text'];
return $row['page_text'];
}
/**
* Send the error message to the user that the access to this page is denied.
* @access private
*/
function err_access_denied()
{
global $db, $session, $paths, $template, $plugins; // Common objects
$ob = '';
$template->tpl_strings['PAGE_NAME'] = 'Access denied';
if ( $this->send_headers )
{
$ob .= $template->getHeader();
}
$ob .= '<div class="error-box"><b>Access to this page is denied.</b><br />This may be because you are not logged in or you have not met certain criteria for viewing this page.</div>';
if ( $this->send_headers )
{
$ob .= $template->getFooter();
}
echo $ob;
}
/**
* Send the error message to the user complaining that there weren't any rows.
* @access private
*/
function err_no_rows()
{
global $db, $session, $paths, $template, $plugins; // Common objects
$title = 'No text rows';
$message = 'While the page\'s existence was verified, there were no rows in the database that matched the query for the text. This may indicate a bug with the software; ask the webmaster for more information. The offending query was:<pre>' . $db->latest_query . '</pre>';
if ( $this->send_headers )
{
$template->tpl_strings['PAGE_NAME'] = $title;
$template->header();
echo "<p>$message</p>";
$template->footer();
}
else
{
echo "<h2>$title</h2>
<p>$message</p>";
}
}
/**
* Tell the user the page doesn't exist, and present them with their options.
* @access private
*/
function err_page_not_existent()
{
global $db, $session, $paths, $template, $plugins; // Common objects
$this->header();
header('HTTP/1.1 404 Not Found');
echo '<h3>There is no page with this title yet.</h3>
<p>You have requested a page that doesn\'t exist yet.';
if ( $session->get_permissions('create_page') )
{
echo ' You can <a href="'.makeUrlNS($this->namespace, $this->page_id, 'do=edit', true).'" onclick="ajaxEditor(); return false;">create this page</a>, or return to the <a href="'.makeUrl(getConfig('main_page')).'">homepage</a>.';
}
else
{
echo ' Return to the <a href="'.makeUrl(getConfig('main_page')).'">homepage</a>.</p>';
}
if ( $session->get_permissions('history_rollback') )
{
$e = $db->sql_query('SELECT * FROM ' . table_prefix . 'logs WHERE action=\'delete\' AND page_id=\'' . $this->page_id . '\' AND namespace=\'' . $this->namespace . '\' ORDER BY time_id DESC;');
if ( !$e )
{
$db->_die('The deletion log could not be selected.');
}
if ( $db->numrows() > 0 )
{
$r = $db->fetchrow();
echo '<p>This page also appears to have some log entries in the database - it seems that it was deleted on ' . $r['date_string'] . '. You can probably <a href="'.makeUrl($paths->page, 'do=rollback&id='.$r['time_id']).'" onclick="ajaxRollback(\''.$r['time_id'].'\'); return false;">roll back</a> the deletion.</p>';
}
$db->free_result();
}
echo '<p>
HTTP Error: 404 Not Found
</p>';
$this->footer();
}
/**
* PHP 4 constructor.
* @see PageProcessor::__construct()
*/
function PageProcessor( $page_id, $namespace )
{
$this->__construct($page_id, $namespace);
}
/**
* Send an error message and die
* @var string Error message
* @var bool If true, send DBAL's debugging information as well
*/
function send_error($message, $sql = false)
{
global $db, $session, $paths, $template, $plugins; // Common objects
$content = "<p>$message</p>";
$template->tpl_strings['PAGE_NAME'] = 'General error in page fetcher';
if ( $this->debug['works'] )
{
$content .= $this->debug['backtrace'];
}
header('HTTP/1.1 500 Internal Server Error');
$template->header();
echo $content;
$template->footer();
$db->close();
exit;
}
} // class PageProcessor
?>