includes/pageprocess.php
author Dan Fuhry <dan@enanocms.org>
Wed, 29 Dec 2010 13:25:32 -0500
changeset 1332 12286b3ee214
parent 1252 e34c23a35dc9
child 1343 2a31905a567d
permissions -rw-r--r--
Added some more hooks to the page editing pipeline. It should now be possible to add controls to the page editor, send the data from them out to the server, and process them on the server side.

<?php

/*
 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
 * pageprocess.php - intelligent retrieval of pages
 * Copyright (C) 2006-2009 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.
 * As of 1.0.4, this also handles the fetching and editing of certain data for pages.
 * @package Enano
 * @subpackage UI
 * @copyright 2007 Dan Fuhry
 * @license GNU General Public License <http://www.gnu.org/licenses/gpl-2.0.html>
 */

class PageProcessor
{
	
	/**
 	* Page ID and namespace of the page handled by this instance
 	* @var string
 	*/
	
	var $page_id;
	var $namespace;
	
	/**
 	* The instance of the namespace processor for the namespace we're doing.
 	* @var object
 	*/
	
	var $ns;
	
	/**
 	* The title of the page sent to the template parser
 	* @var string
 	*/
	
	var $title = '';
	
	/**
 	* The information about the page(s) we were redirected from
 	* @var array
 	*/
	
	var $redirect_stack = array();
	
	/**
 	* The revision ID (history entry) to send. If set to 0 (the default) then the most recent revision will be sent.
 	* @var int
 	*/
	
	var $revision_id = 0;
	
	/**
 	* The time this revision was saved, as a UNIX timestamp
 	* @var int
 	*/
	
	var $revision_time = 0;
	
	/**
 	* Unsanitized page ID.
 	* @var string
 	*/
	
	var $page_id_unclean;
	
	/**
 	* 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;
	
	/**
 	* The SHA1 hash of the user-inputted password for the page
 	* @var string
 	*/
 	
	var $password = '';
	
	/**
 	* Switch to track if redirects are allowed. Defaults to true.
 	* @var bool
 	*/
	
	var $allow_redir = true;
	
	/**
 	* Holds any error message from redirection code. Defaults to false (no error).
 	* @var mixed
 	*/
 	
	var $redir_error = false;
	
	/**
 	* 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' => false,
			'works'  => false
		);
	
	/**
 	* The list of errors raised in the class.
 	* @var array
 	*/
	
	var $_errors = array();
	
	/**
 	* Constructor.
 	* @param string The page ID (urlname) of the page
 	* @param string The namespace of the page
 	* @param int Optional. The revision ID to send.
 	*/
	
	function __construct( $page_id, $namespace, $revision_id = 0 )
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		
		profiler_log("PageProcessor [{$namespace}:{$page_id}]: Started constructor");
		
		// 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.');
		}
		
		if ( !is_int($revision_id) )
			$revision_id = 0;
		
		$this->_setup( $page_id, $namespace, $revision_id );
	}
	
	/**
 	* The main method to send the page content. Also responsible for checking permissions and calling the statistics counter.
 	* @param bool If true, the stat counter is called. Defaults to false.
 	*/
	
	function send( $do_stats = false )
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $lang, $output;
		
		profiler_log('PageProcessor: send() called');
		
		if ( !$this->perms->get_permissions('read') )
		{
			// Permission denied to read page. Is this one of our core pages that must always be allowed?
			// NOTE: Not even the administration panel will work if ACLs deny access to it.
			if ( $this->namespace == 'Special' && in_array($this->page_id, array('Login', 'Logout', 'LangExportJSON', 'CSS')) )
			{
				// Do nothing; allow execution to continue
			}
			else
			{
				// Page isn't whitelisted, behave as normal
				$this->err_access_denied();
				return false;
			}
		}
		if ( $this->revision_id > 0 && !$this->perms->get_permissions('history_view') )
		{
			$this->err_access_denied();
			return false;
		}
		
		// Is there a custom function registered for handling this namespace?
		// DEPRECATED (even though it only saw its way into one alpha release.)
		if ( $proc = $paths->get_namespace_processor($this->namespace) )
		{
			// yes, just call that
			// this is protected aggressively by the PathManager against overriding critical namespaces
			return call_user_func($proc, $this);
		}
		
		$pathskey = $paths->nslist[ $this->namespace ] . $this->page_id;
		$strict_no_headers = false;
		$admin_fail = false;
		if ( $this->namespace == 'Admin' && strstr($this->page_id, '/') )
		{
			$this->page_id = substr($this->page_id, 0, strpos($this->page_id, '/'));
			$funcname = "page_{$this->namespace}_{$this->page_id}";
			if ( function_exists($funcname) )
			{
				$this->page_exists = true;
			}
		}
		if ( isPage($pathskey) )
		{
			$cdata = $this->ns->get_cdata();
			
			if ( $cdata['special'] == 1 )
			{
				$this->send_headers = false;
				$strict_no_headers = true;
				$GLOBALS['output'] = new Output_Naked();
			}
			if ( isset($cdata['password']) )
			{
				if ( $cdata['password'] != '' && $cdata['password'] != sha1('') )
				{
					$password =& $cdata['password'];
					if ( $this->password != $password )
					{
						$this->err_wrong_password();
						return false;
					}
				}
			}
			if ( isset($cdata['require_admin']) && $cdata['require_admin'] )
			{
				if ( $session->auth_level < USER_LEVEL_ADMIN )
				{
					$admin_fail = true;
				}
			}
		}
		else if ( $this->namespace === $paths->namespace && $this->page_id == $paths->page_id )
		{
			if ( isset($paths->cpage['require_admin']) && $paths->cpage['require_admin'] )
			{
				if ( $session->auth_level < USER_LEVEL_ADMIN )
				{
					$admin_fail = true;
				}
			}
		}
		if ( $admin_fail )
		{
			header('Content-type: text/javascript');
			echo enano_json_encode(array(
					'mode' => 'error',
					'error' => 'need_auth_to_admin'
				));
			return true;
		}
		if ( $this->page_exists && $this->namespace != 'Special' && $this->namespace != 'Admin' && $do_stats )
		{
			require_once(ENANO_ROOT.'/includes/stats.php');
			doStats($this->page_id, $this->namespace);
		}
		
		// We are all done. Ship off the page.
		
		if ( !$this->allow_redir )
		{
			if ( method_exists($this->ns, 'get_redirect') )
			{
				if ( $result = $this->ns->get_redirect() )
					display_redirect_notice($result['page_id'], $result['namespace']);
			}
		}
		else
		{
			$this->process_redirects();
			
			if ( count($this->redirect_stack) > 0 )
			{
				$stack = array_reverse($this->redirect_stack);
				foreach ( $stack as $stackel )
				{
					$url = makeUrlNS($stackel['old_namespace'], $stackel['old_page_id'], 'redirect=no', true);
					$page_data = $this->ns->get_cdata();
					$title = $stackel['old_title'];
					$a = '<a href="' . $url . '">' . htmlspecialchars($title) . '</a>';
					$output->add_after_header('<small>' . $lang->get('page_msg_redirected_from', array('from' => $a)) . '<br /></small>');
				}
				$template->set_page($this);
			}
			
			if ( $this->redir_error )
			{
				$output->add_after_header('<div class="usermessage"><b>' . $this->redir_error . '</b></div>');
				$result = $this->ns->get_redirect();
				display_redirect_notice($result['page_id'], $result['namespace']);
			}
		}
		
		$this->ns->send();
	}
	
	/**
 	* Sends the page through by fetching it from the database.
 	*/
 	
	function send_from_db($strict_no_headers = false)
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $lang;
		
		$this->ns->send_from_db();
	}
	
	/**
 	* Fetches the wikitext or HTML source for the page.
 	* @return string
 	*/
	
	function fetch_source()
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		
		if ( !$this->perms->get_permissions('view_source') )
		{
			return false;
		}
		if ( !$this->page_exists )
		{
			return '';
		}
		$cdata = $this->ns->get_cdata();
		if ( isset($cdata['password']) )
		{
			if ( $cdata['password'] != sha1('') && $cdata['password'] !== $this->password && !empty($cdata['password']) )
			{
				return false;
			}
		}
		return $this->fetch_text();
	}
	
	/**
 	* Updates (saves/changes/edits) the content of the page.
 	* @param string The new text for the page
 	* @param string A summary of edits made to the page.
 	* @param bool If true, the edit is marked as a minor revision
 	* @param string Page format - wikitext or xhtml. REQUIRED, and new in 1.1.6.
 	* @param array Optional - the entire incoming request. Plugins can add their own data to it.
 	* @return bool True on success, false on failure. When returning false, it will push errors to the PageProcessor error stack; read with $page->pop_error()
 	*/
	
	function update_page($text, $edit_summary = false, $minor_edit = false, $page_format, $raw_request = array())
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $lang;
		
		// Create the page if it doesn't exist
		$page_just_created = false;
		if ( !$this->page_exists )
		{
			if ( !$this->create_page() )
			{
				return false;
			}
			// This is just to tell plugins if a page was just created, or is being edited.
			$page_just_created = true;
		}
			
		//
		// Validation
		//
		
		$page_id = $db->escape($this->page_id);
		$namespace = $db->escape($this->namespace);
		
		$q = $db->sql_query('SELECT protected FROM ' . table_prefix . "pages WHERE urlname='$page_id' AND namespace='$namespace';");
		if ( !$q )
			$db->_die('PageProcess updating page content');
		if ( $db->numrows() < 1 )
		{
			$this->raise_error($lang->get('editor_err_no_rows'));
			return false;
		}
		
		// Do we have permission to edit the page?
		if ( !$this->perms->get_permissions('edit_page') )
		{
			$this->raise_error($lang->get('editor_err_no_permission'));
			return false;
		}
		
		list($protection) = $db->fetchrow_num();
		$db->free_result();
		
		if ( $protection == 1 )
		{
			// The page is protected - do we have permission to edit protected pages?
			if ( !$this->perms->get_permissions('even_when_protected') )
			{
				$this->raise_error($lang->get('editor_err_page_protected'));
				return false;
			}
		}
		else if ( $protection == 2 )
		{
			// The page is semi-protected.
			if (
 					( !$session->user_logged_in || // Is the user logged in?
 						( $session->user_logged_in && $session->reg_time + ( 4 * 86400 ) >= time() ) ) // If so, have they been registered for 4 days?
 					&& !$this->perms->get_permissions('even_when_protected') ) // And of course, is there an ACL that overrides semi-protection?
			{
				$this->raise_error($lang->get('editor_err_page_protected'));
				return false;
			}
		}
		
		// Spam check
		if ( !spamalyze($text) )
		{
			$this->raise_error($lang->get('editor_err_spamcheck_failed'));
			return false;
		}
		
		// Page format check
		if ( !in_array($page_format, array('xhtml', 'wikitext')) )
		{
			$this->raise_error("format \"$page_format\" not one of [xhtml, wikitext]");
			return false;
		}
		
		//
		// Protection validated; update page content
		//
		
		$text_undb = RenderMan::preprocess_text($text, false, false);
		$text = $db->escape($text_undb);
		$author = $db->escape($session->username);
		$time = time();
		$edit_summary = ( strval($edit_summary) === $edit_summary ) ? $db->escape($edit_summary) : '';
		$minor_edit = ( $minor_edit ) ? '1' : '0';
		$date_string = enano_date(ED_DATE | ED_TIME);
		
		// Allow stuff to be run when the page is saved
		$code = $plugins->setHook('update_page');
		foreach ( $code as $cmd )
		{
			eval($cmd);
		}
		// If a plugin raised an error, honor it.
		if ( $this->_errors )
		{
			return false;
		}
		
		// Insert log entry
		$sql = 'INSERT INTO ' . table_prefix . "logs ( time_id, date_string, log_type, action, page_id, namespace, author, author_uid, page_text, edit_summary, minor_edit, page_format )\n"
 				. "  VALUES ( $time, '$date_string', 'page', 'edit', '{$this->page_id}', '{$this->namespace}', '$author', $session->user_id, '$text', '$edit_summary', $minor_edit, '$page_format' );";
		if ( !$db->sql_query($sql) )
		{
			$this->raise_error($db->get_error());
			return false;
		}
		
		// Update the master text entry
		$sql = 'UPDATE ' . table_prefix . "page_text SET page_text = '$text' WHERE page_id = '{$this->page_id}' AND namespace = '{$this->namespace}';";
		if ( !$db->sql_query($sql) )
		{
			$this->raise_error($db->get_error());
			return false;
		}
		
		// If there's an identical draft copy, delete it
		$sql = 'DELETE FROM ' . table_prefix . "logs WHERE is_draft = 1 AND page_id = '{$this->page_id}' AND namespace = '{$this->namespace}' AND page_text = '{$text}';";
		if ( !$db->sql_query($sql) )
		{
			$this->raise_error($db->get_error());
			return false;
		}
		
		// Set page_format
		// Using @ due to warning thrown when saving new page
		$cdata = $this->ns->get_cdata();
		if ( @$cdata['page_format'] !== $page_format )
		{
			// Note: no SQL injection to worry about here. Everything that goes into this is sanitized already, barring some rogue plugin.
			// (and if there's a rogue plugin running, we have bigger things to worry about anyway.)
			if ( !$db->sql_query('UPDATE ' . table_prefix . "pages SET page_format = '$page_format' WHERE urlname = '$this->page_id' AND namespace = '$this->namespace';") )
			{
				$this->raise_error($db->get_error());
				return false;
			}
			$paths->update_metadata_cache();
		}
		
		// Rebuild the search index
		$paths->rebuild_page_index($this->page_id, $this->namespace);
		
		$this->text_cache = $text_undb;
		
		return true;
		
	}
	
	/**
 	* Creates the page if it doesn't already exist.
 	* @param string Optional page title.
 	* @param bool Visibility (allow indexing) flag
 	* @return bool True on success, false on failure.
 	*/
	
	function create_page($title = false, $visible = true)
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $lang;
		
		// Do we have permission to create the page?
		if ( !$this->perms->get_permissions('create_page') )
		{
			$this->raise_error($lang->get('pagetools_create_err_no_permission'));
			return false;
		}
		
		// Does it already exist?
		if ( $this->page_exists )
		{
			$this->raise_error($lang->get('pagetools_create_err_already_exists'));
			return false;
		}
		
		// It's not in there. Perform validation.
		
		// We can't create special, admin, or external pages.
		if ( $this->namespace == 'Special' || $this->namespace == 'Admin' || $this->namespace == 'API' )
		{
			$this->raise_error($lang->get('pagetools_create_err_nodb_namespace'));
			return false;
		}
		
		// Guess the proper title
		$name = ( !empty($title) ) ? $title : str_replace('_', ' ', dirtify_page_id($this->page_id));
		
		// Check for the restricted Project: prefix
		if ( substr($this->page_id, 0, 8) == 'Project:' )
		{
			$this->raise_error($lang->get('pagetools_create_err_reserved_prefix'));
			return false;
		}
		
		// Validation successful - insert the page
		
		$metadata = array(
				'urlname' => $this->page_id,
				'namespace' => $this->namespace,
				'name' => $name,
				'special' => 0,
				'visible' => $visible ? 1 : 0,
				'comments_on' => 1,
				'protected' => ( $this->namespace == 'System' ? 1 : 0 ),
				'delvotes' => 0,
				'delvote_ips' => serialize(array()),
				'wiki_mode' => 2
			);
		
		$paths->add_page($metadata);
		
		$page_id = $db->escape($this->page_id);
		$namespace = $db->escape($this->namespace);
		$name = $db->escape($name);
		$protect = ( $this->namespace == 'System' ) ? '1' : '0';
		$blank_array = $db->escape(serialize(array()));
		
		// Query 1: Metadata entry
		$q = $db->sql_query('INSERT INTO ' . table_prefix . "pages(name, urlname, namespace, visible, protected, delvotes, delvote_ips, wiki_mode)\n"
											. "  VALUES ( '$name', '$page_id', '$namespace', {$metadata['visible']}, $protect, 0, '$blank_array', 2 );");
		if ( !$q )
			$db->_die('PageProcessor page creation - metadata stage');
		
		// Query 2: Text insertion
		$q = $db->sql_query('INSERT INTO ' . table_prefix . "page_text(page_id, namespace, page_text)\n"
												. "VALUES ( '$page_id', '$namespace', '' );");
		if ( !$q )
			$db->_die('PageProcessor page creation - text stage');
		
		// Query 3: Log entry
		$db->sql_query('INSERT INTO ' . table_prefix."logs(time_id, date_string, log_type, action, author, author_uid, page_id, namespace)\n"
 									. "  VALUES ( " . time() . ", 'DEPRECATED', 'page', 'create', \n"
 									. "          '" . $db->escape($session->username) . "', $session->user_id, '" . $db->escape($this->page_id) . "', '" . $this->namespace . "');");
		if ( !$q )
			$db->_die('PageProcessor page creation - logging stage');
		
		// Update the cache
		$paths->update_metadata_cache();
		
		// Make sure that when/if we save the page later in this instance it doesn't get re-created
		$this->page_exists = true;
		
		// Page created. We're good!
		return true;
	}
	
	/**
 	* Rolls back a non-edit action in the logs
 	* @param int Log entry (log_id) to roll back
 	* @return array Standard Enano error/success protocol
 	*/
	
	function rollback_log_entry($log_id)
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $cache;
		
		// Verify permissions
		if ( !$this->perms->get_permissions('history_rollback') )
		{
			return array(
				'success' => false,
				'error' => 'access_denied'
				);
		}
		
		// Check input
		$log_id = intval($log_id);
		if ( empty($log_id) )
		{
			return array(
				'success' => false,
				'error' => 'invalid_parameter'
				);
		}
		
		// Fetch the log entry
		$q = $db->sql_query('SELECT * FROM ' . table_prefix . "logs WHERE log_type = 'page' AND page_id='{$this->page_id}' AND namespace='{$this->namespace}' AND log_id = $log_id;");
		if ( !$q )
			$db->_die();
		
		// Is this even a valid log entry for this context?
		if ( $db->numrows() < 1 )
		{
			return array(
				'success' => false,
				'error' => 'entry_not_found'
				);
		}
		
		// All good, fetch and free the result
		$log_entry = $db->fetchrow();
		$db->free_result();
		
		$dateline = enano_date(ED_DATE | ED_TIME, $log_entry['time_id']);
		
		// Let's see, what do we have here...
		switch ( $log_entry['action'] )
		{
			case 'rename':
				// Page was renamed, let the rename method handle this
				return array_merge($this->rename_page($log_entry['edit_summary']), array('dateline' => $dateline, 'action' => $log_entry['action']));
				break;
			case 'prot':
			case 'unprot':
			case 'semiprot':
				return array_merge($this->protect_page(intval($log_entry['page_text']), '__REVERSION__'), array('dateline' => $dateline, 'action' => $log_entry['action']));
				break;
			case 'delete':
				
				// Raising a previously dead page has implications...
				
				// FIXME: l10n
				// rollback_extra is required because usually only moderators can undo page deletion AND restore the content.
				// potential flaw here - once recreated, can past revisions be restored by users without rollback_extra? should
				// probably modify editor routine to deny revert access if the timestamp < timestamp of last deletion if any.
				if ( !$this->perms->get_permissions('history_rollback_extra') )
					return 'Administrative privileges are required for page undeletion.';
				
				// Rolling back the deletion of a page that was since created?
				$pathskey = $paths->nslist[ $this->namespace ] . $this->page_id;
				if ( isPage($pathskey) )
					return array(
							'success' => false,
							// This is a clean Christian in-joke.
							'error' => 'seeking_living_among_dead'
						);
				
				// Generate a crappy page name
				$name = $db->escape( str_replace('_', ' ', dirtify_page_id($this->page_id)) );
				
				// Stage 1 - re-insert page
				$e = $db->sql_query('INSERT INTO ' . table_prefix.'pages(name,urlname,namespace) VALUES( \'' . $name . '\', \'' . $this->page_id . '\',\'' . $this->namespace . '\' )');
				if ( !$e )
					$db->die_json();
				
				// Select the latest published revision
				$q = $db->sql_query('SELECT page_text FROM ' . table_prefix . "logs WHERE\n"
													. "      log_type  = 'page'\n"
													. "  AND action    = 'edit'\n"
													. "  AND page_id   = '$this->page_id'\n"
													. "  AND namespace = '$this->namespace'\n"
													. "  AND is_draft != 1\n"
													. "ORDER BY time_id DESC LIMIT 1;");
				if ( !$q )
					$db->die_json();
				list($page_text) = $db->fetchrow_num();
				$db->free_result($q);
				
				// Apply the latest revision as the current page text
				$page_text = $db->escape($page_text);
				$e = $db->sql_query('INSERT INTO ' . table_prefix."page_text(page_id, namespace, page_text) VALUES\n"
													. "  ( '$this->page_id', '$this->namespace', '$page_text' );");
				if ( !$e )
					$db->die_json();
				
				$cache->purge('page_meta');
				
				return array(
						'success' => true,
						'dateline' => $dateline,
						'action' => $log_entry['action']
					);
				
				break;
			case 'reupload':
				
				// given a log id and some revision info, restore the old file.
				// get the timestamp of the file before this one
				$q = $db->sql_query('SELECT time_id, file_key, file_extension, filename, size, mimetype FROM ' . table_prefix . "files WHERE time_id < {$log_entry['time_id']} ORDER BY time_id DESC LIMIT 1;");
				if ( !$q )
					$db->_die();
				
				$row = $db->fetchrow();
				$db->free_result();
				
				// If the file hasn't been renamed to the new format (omitting timestamp), do that now.
				$fname = ENANO_ROOT . "/files/{$row['file_key']}_{$row['time_id']}{$row['file_extension']}";
				if ( @file_exists($fname) )
				{
					// it's stored in the old format - rename
					$fname_new = ENANO_ROOT . "/files/{$row['file_key']}{$row['file_extension']}";
					if ( !@rename($fname, $fname_new) )
					{
						return array(
							'success' => false,
							'error' => 'rb_file_rename_failed',
							'action' => $log_entry['action']
							);
					}
				}
				
				// Insert a new file entry
				$time = time();
				$filename = $db->escape($row['filename']);
				$mimetype = $db->escape($row['mimetype']);
				$ext = $db->escape($row['file_extension']);
				$key = $db->escape($row['file_key']);
				
				$q = $db->sql_query('INSERT INTO ' . table_prefix . "files ( time_id, page_id, filename, size, mimetype, file_extension, file_key ) VALUES\n"
							. "  ( $time, '$this->page_id', '$filename', {$row['size']}, '$mimetype', '$ext', '$key' );");
				if ( !$q )
					$db->die_json();
				
				// add reupload log entry
				$username = $db->escape($session->username);
				$q = $db->sql_query('INSERT INTO ' . table_prefix . "logs ( log_type, action, time_id, page_id, namespace, author, author_uid, edit_summary ) VALUES\n"
													. "  ( 'page', 'reupload', $time, '$this->page_id', '$this->namespace', '$username', $session->user_id, '__ROLLBACK__' )");
				if ( !$q )
					$db->die_json();
				
				return array(
						'success' => true,
						'dateline' => $dateline,
						'action' => $log_entry['action']
					);
				
				break;
			case 'votereset':
				if ( !$this->perms->get_permissions('history_rollback_extra') )
					return 'Denied!';
				
				// pull existing vote data
				$q = $db->sql_query('SELECT delvotes, delvote_ips FROM ' . table_prefix . "pages WHERE urlname = '$this->page_id' AND namespace = '$this->namespace';");
				if ( !$q )
					$db->_die();
				
				if ( $db->numrows() < 1 )
					return array(
							'success' => false,
							'error' => 'page_not_exist',
							'action' => $log_entry['action']
						);
					
				list($curr_delvotes, $curr_delvote_ips) = $db->fetchrow_num();
				$db->free_result();
				
				// merge with existing votes
				$old_delvote_ips = unserialize($log_entry['page_text']);
				$new_delvote_ips = unserialize($curr_delvote_ips);
				$new_delvote_ips['u'] = array_unique(array_merge($new_delvote_ips['u'], $old_delvote_ips['u']));
				$new_delvote_ips['ip'] = array_unique(array_merge($new_delvote_ips['ip'], $old_delvote_ips['ip']));
				$new_delvotes = count($new_delvote_ips['ip']);
				$new_delvote_ips = $db->escape(serialize($new_delvote_ips));
				
				// update pages table
				$q = $db->sql_query('UPDATE ' . table_prefix . "pages SET delvotes = $new_delvotes, delvote_ips = '$new_delvote_ips' WHERE urlname = '$this->page_id' AND namespace = '$this->namespace';");
				
				$cache->purge('page_meta');
				
				return array(
						'success' => true,
						'dateline' => $dateline,
						'action' => $log_entry['action']
					);
				break;
			default:
				
				return array(
						'success' => false,
						'error' => 'rb_action_not_supported',
						'action' => $log_entry['action']
					);
				
				break;
		}
	}
	
	/**
 	* Renames the page
 	* @param string New name
 	* @return array Standard Enano error/success protocol
 	*/
	
	function rename_page($new_name)
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		
		// Check permissions
		if ( !$this->perms->get_permissions('rename') )
		{
			return array(
				'success' => false,
				'error' => 'access_denied'
				);
		}
		
		// If this is the same as the current name, return success
		$page_name = get_page_title_ns($this->page_id, $this->namespace);
		if ( $page_name === $new_name )
		{
			return array(
				'success' => true
				);
		}
		
		// Make sure the name is valid
		$new_name = trim($new_name);
		if ( empty($new_name) )
		{
			return array(
				'success' => false,
				'error' => 'invalid_parameter'
				);
		}
		
		// Log the action
		$username = $db->escape($session->username);
		$page_name = $db->escape($page_name);
		$time = time();
		
		$q = $db->sql_query('INSERT INTO ' . table_prefix . "logs ( log_type, action, page_id, namespace, author, author_uid, edit_summary, time_id, date_string ) VALUES\n"
											. "  ( 'page', 'rename', '{$this->page_id}', '{$this->namespace}', '$username', $session->user_id, '$page_name', '$time', 'DATE_STRING COLUMN OBSOLETE, USE time_id' );");
		if ( !$q )
			$db->_die();
		
		// Not much to do but to rename it now
		$new_name = $db->escape($new_name);
		$q = $db->sql_query('UPDATE ' . table_prefix . "pages SET name = '$new_name' WHERE urlname = '{$this->page_id}' AND namespace = '{$this->namespace}';");
		if ( !$q )
			$db->_die();
		
		// Update the cache
		$paths->update_metadata_cache();
		
		return array(
			'success' => true
			);
	}
	
	/**
 	* Sets the protection level of the page
 	* @param int Protection level, one of PROTECT_{FULL,SEMI,NONE}
 	* @param string Reason for protection - required
 	*/
	
	function protect_page($protection_level, $reason)
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $cache;
		
		// Validate permissions
		if ( !$this->perms->get_permissions('protect') )
		{
			return array(
				'success' => false,
				'error' => 'access_denied'
				);
		}
		
		// Validate re-auth
		if ( !$session->sid_super )
		{
			return array(
				'success' => false,
				'error' => 'access_denied_need_reauth'
				);
		}
		
		// Validate input
		$reason = trim($reason);
		if ( !in_array($protection_level, array(PROTECT_NONE, PROTECT_FULL, PROTECT_SEMI)) || empty($reason) )
		{
			return array(
				'success' => false,
				'error' => 'invalid_parameter'
				);
		}
		
		// Retrieve page metadata
		$metadata = $this->ns->get_cdata();
		
		// Log the action
		$username = $db->escape($session->username);
		$time = time();
		$existing_protection = intval($metadata['protected']);
		$reason = $db->escape($reason);
		
		if ( $existing_protection == $protection_level )
		{
			return array(
				'success' => false,
				'error' => 'protection_already_there'
				);
		}
		
		$action = '[ insanity ]';
		switch($protection_level)
		{
			case PROTECT_FULL: $action = 'prot'; break;
			case PROTECT_NONE: $action = 'unprot'; break;
			case PROTECT_SEMI: $action = 'semiprot'; break;
		}
		
		$sql = 'INSERT INTO ' . table_prefix . "logs ( log_type, action, page_id, namespace, author, author_uid, edit_summary, time_id, page_text, date_string ) VALUES\n"
				. "  ( 'page', '$action', '{$this->page_id}', '{$this->namespace}', '$username', {$session->user_id}, '$reason', '$time', '$existing_protection', 'DATE_STRING COLUMN OBSOLETE, USE time_id' );";
		if ( !$db->sql_query($sql) )
		{
			$db->die_json();
		}
		
		// Perform the actual protection
		$q = $db->sql_query('UPDATE ' . table_prefix . "pages SET protected = $protection_level WHERE urlname = '{$this->page_id}' AND namespace = '{$this->namespace}';");
		if ( !$q )
			$db->die_json();
		
		$cache->purge('page_meta');
		
		return array(
			'success' => true
			);
	}
	
	/**
 	* Sets internal variables.
 	* @access private
 	*/
	
	function _setup($page_id, $namespace, $revision_id)
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		
		$page_id_cleaned = sanitize_page_id($page_id);
		
		$this->revision_id = $revision_id;
		$this->page_id_unclean = dirtify_page_id($page_id);
		
		// resolve namespace
		$this->ns = namespace_factory($page_id, $namespace, $this->revision_id);
		$this->page_id =& $this->ns->page_id;
		$this->namespace =& $this->ns->namespace;
		
		$this->perms = $session->fetch_page_acl( $page_id, $namespace );
		
		$this->page_exists = $this->ns->exists();
		$this->title = get_page_title_ns($this->page_id, $this->namespace);
		
		profiler_log("PageProcessor [{$this->namespace}:{$this->page_id}]: Ran _setup()");
	}
	
	/**
 	* Processes any redirects.
 	* @access private
 	*/
	
	function process_redirects()
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $output, $lang;
		
		$this->redirect_stack = array();
		
		if ( !method_exists($this->ns, 'get_redirect') )
			return true;
		
		if ( !$this->allow_redir )
			return true;
		
		$redirect_count = 0;
		
		while ( $result = $this->ns->get_redirect() )
		{
			if ( $result['namespace'] == 'Special' || $result['namespace'] == 'Admin' )
			{
				// Can't redirect to special/admin page
				$this->redir_error = $lang->get('page_err_redirect_to_special');
				break;
			}
			if ( $redirect_count == 3 )
			{
				// max of 3 internal redirects exceeded
				$this->redir_error = $lang->get('page_err_redirects_exceeded');
				break;
			}
			
			$loop = false;
			foreach ( $this->redirect_stack as $stackel )
			{
				if ( $result['page_id'] == $stackel['old_page_id'] && $result['namespace'] == $stackel['old_namespace'] )
				{
					$loop = true;
					break;
				}
			}
			
			if ( $loop )
			{
				// redirect loop
				$this->redir_error = $lang->get('page_err_redirect_infinite_loop');
				break;
			}
			$new_ns = namespace_factory($result['page_id'], $result['namespace']);
			if ( !$new_ns->exists() )
			{
				// new page doesn't exist
				$this->redir_error = $lang->get('page_err_redirect_to_nonexistent');
				break;
			}
			
			// build stack entry
			$stackel = array(
					'page_id' => $result['page_id'],
					'namespace' => $result['namespace'],
					'old_page_id' => $this->page_id,
					'old_namespace' => $this->namespace,
					'old_title' => $this->ns->title
				);
			
			// replace everything (perform the actual redirect)
			$this->ns = $new_ns;
			
			$this->page_id =& $this->ns->page_id;
			$this->namespace =& $this->ns->namespace;
			
			$this->redirect_stack[] = $stackel;
			
			$redirect_count++;
		}
	}
		
	/**
 	* 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()
	{
		return $this->ns->fetch_text();
	}
	
	/**
 	* Tells us if the page exists.
 	* @return bool
 	*/
	
	function exists()
	{
		return $this->ns->exists();
	}
	
	/**
 	* 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
		global $lang;
		global $email;
		
		// Log it for crying out loud
		$q = $db->sql_query('INSERT INTO '.table_prefix.'logs(log_type,action,time_id,date_string,author,author_uid,edit_summary,page_text) VALUES(\'security\', \'illegal_page\', '.time().', \'DEPRECATED\', \''.$db->escape($session->username).'\', ' . $session->user_id . ', \''.$db->escape($_SERVER['REMOTE_ADDR']).'\', \'' . $db->escape(serialize(array($this->page_id, $this->namespace))) . '\')');
		
		$ob = '';
		//$template->tpl_strings['PAGE_NAME'] = 'Access denied';
		$template->tpl_strings['PAGE_NAME'] = htmlspecialchars( $this->title );
			
		if ( $this->send_headers )
		{
			$ob .= $template->getHeader();
		}
		
		if ( count($this->redirect_stack) > 0 )
		{
			$stack = array_reverse($this->redirect_stack);
			foreach ( $stack as $oldtarget )
			{
				$url = makeUrlNS($oldtarget[1], $oldtarget[0], 'redirect=no', true);
				$old_page = namespace_factory($oldtarget[0], $oldtarget[1]);
				$page_data = $old_page->get_cdata();
				$title = ( isset($page_data['name']) ) ? $page_data['name'] : $paths->nslist[$oldtarget[1]] . htmlspecialchars( str_replace('_', ' ', dirtify_page_id( $oldtarget[0] ) ) );
				$a = '<a href="' . $url . '">' . $title . '</a>';
				
				$url = makeUrlNS($this->namespace, $this->page_id, 'redirect=no', true);
				$page_data = $this->ns->get_cdata();
				$title = ( isset($page_data['name']) ) ? $page_data['name'] : $paths->nslist[$this->namespace] . htmlspecialchars( str_replace('_', ' ', dirtify_page_id( $this->page_id ) ) );
				$b = '<a href="' . $url . '">' . $title . '</a>';
				
				$ob .= '<small>' . $lang->get('page_msg_redirected_from_to', array('from' => $a, 'to' => $b)) . '<br /></small>';
			}
		}
		
		$email_link = $email->encryptEmail(getConfig('contact_email'), '', '', $lang->get('page_err_access_denied_siteadmin'));
		
		$ob .= "<h3>" . $lang->get('page_err_access_denied_title') . "</h3>";
		$ob .= "<p>" . $lang->get('page_err_access_denied_body', array('site_administration' => $email_link)) . "</p>";
		
		if ( $this->send_headers )
		{
			$ob .= $template->getFooter();
		}
		echo $ob;
	}
	
	/**
 	* Inform the user of an incorrect or absent password
 	* @access private
 	*/
 	
	function err_wrong_password()
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $lang;
		
		$title = $lang->get('page_msg_passrequired_title');
		$message = ( empty($this->password) ) ?
 								'<p>' . $lang->get('page_msg_passrequired') . '</p>' :
 								'<p>' . $lang->get('page_msg_pass_wrong') . '</p>';
		$message .= '<form action="' . makeUrlNS($this->namespace, $this->page_id) . '" method="post">
 									<p>
 										<label>' . $lang->get('page_lbl_password') . ' <input name="pagepass" type="password" /></label>&nbsp;&nbsp;<input type="submit" value="' . $lang->get('page_btn_password_submit') . '" />
 									</p>
 								</form>';
		if ( $this->send_headers )
		{
			$template->tpl_strings['PAGE_NAME'] = $title;
			$template->header();
			echo "$message";
			$template->footer();
		}
		else
		{
			echo "<h2>$title</h2>
						$message";
		}
	}
	
	/**
 	* 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>";
		}
	}
	
	/**
 	* Send an error message and die. For debugging or critical technical errors only - nothing that would under normal circumstances be shown to the user.
 	* @param string Error message
 	* @param bool If true, send DBAL's debugging information as well
 	*/
 	
	function send_error($message, $sql = false)
	{
		global $db, $session, $paths, $template, $plugins; // Common objects
		global $lang;
		
		$content = "<p>$message</p>";
		$template->tpl_strings['PAGE_NAME'] = $lang->get('page_msg_general_error');
		
		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;
		
	}
	
	/**
 	* Raises an error.
 	* @param string Error string
 	*/
 	
	function raise_error($string)
	{
		if ( !is_string($string) )
			return false;
		$this->_errors[] = $string;
	}
	
	/**
 	* Retrieves the latest error from the error stack and returns it ('pops' the error stack)
 	* @return string
 	*/
	
	function pop_error()
	{
		if ( count($this->_errors) < 1 )
			return false;
		return array_pop($this->_errors);
	}
	
} // class PageProcessor

?>