path: root/Zotlabs/Module/Wiki.php

<?php /** @file */

namespace Zotlabs\Module;

use \Zotlabs\Lib as Zlib;
use \Michelf\MarkdownExtra;

require_once('include/acl_selectors.php');
require_once('include/conversation.php');
require_once('include/bbcode.php');


class Wiki extends \Zotlabs\Web\Controller {

	private $wiki = null;

	function init() {
		// Determine which channel's wikis to display to the observer
		$nick = null;
		if (argc() > 1)
			$nick = argv(1); // if the channel name is in the URL, use that
		if (! $nick && local_channel()) { // if no channel name was provided, assume the current logged in channel
			$channel = \App::get_channel();
			if ($channel && $channel['channel_address']) {
				$nick = $channel['channel_address'];
				goaway(z_root() . '/wiki/' . $nick);
			}
		}
		if (! $nick) {
			notice( t('Profile Unavailable.') . EOL);
			goaway(z_root());
		}

		profile_load($nick);
	}

	function get() {

		if(observer_prohibited(true)) {
			return login();
		}

		if(! feature_enabled(\App::$profile_uid,'wiki')) {
			notice( t('Not found') . EOL);
     		return;
 		}


		if(! perm_is_allowed(\App::$profile_uid,get_observer_hash(),'view_wiki')) {
			notice( t('Permission denied.') . EOL);
			return;
		}

		// TODO: Combine the interface configuration into a unified object
		// Something like $interface = array('new_page_button' => false, 'new_wiki_button' => false, ...)

		$wiki_owner = false;
		$showNewWikiButton = false;
		$pageHistory = array();
		$local_observer = null;
		$resource_id = '';
		
		// init() should have forced the URL to redirect to /wiki/channel so assume argc() > 1

		$nick = argv(1);
		$owner = channelx_by_nick($nick);  // The channel who owns the wikis being viewed
		if(! $owner) {
			notice( t('Invalid channel') . EOL);
			goaway('/' . argv(0));
		}

		$observer_hash = get_observer_hash();

		// Determine if the observer is the channel owner so the ACL dialog can be populated
		if (local_channel() === intval($owner['channel_id'])) {

			$wiki_owner = true;

			// Obtain the default permission settings of the channel
			$owner_acl = array(
				'allow_cid' => $owner['channel_allow_cid'],
				'allow_gid' => $owner['channel_allow_gid'],
				'deny_cid' => $owner['channel_deny_cid'],
				'deny_gid' => $owner['channel_deny_gid']
			);

			// Initialize the ACL to the channel default permissions

			$x = array(
					'lockstate' => (( $owner['channel_allow_cid'] || 
						$owner['channel_allow_gid'] || 
						$owner['channel_deny_cid'] || 
						$owner['channel_deny_gid'])
						? 'lock' : 'unlock'
					),
					'acl' => populate_acl($owner_acl),
					'allow_cid' => acl2json($owner_acl['allow_cid']),
					'allow_gid' => acl2json($owner_acl['allow_gid']),
					'deny_cid'  => acl2json($owner_acl['deny_cid']),
					'deny_gid'  => acl2json($owner_acl['deny_gid']),
					'bang' => ''
			);
		}
		else {
			// Not the channel owner 
			$owner_acl = $x = array();
		}

		$is_owner = ((local_channel()) && (local_channel() == \App::$profile['profile_uid']) ? true : false);
		//$o = profile_tabs($a, $is_owner, \App::$profile['channel_address']);
		$o = '';

		// Download a wiki
/*
		if((argc() > 3) && (argv(2) === 'download') && (argv(3) === 'wiki')) {

			$resource_id = argv(4);

			$w = Zlib\NativeWiki::get_wiki($owner,$observer_hash,$resource_id);
			if(! $w['htmlName']) {
				notice(t('Error retrieving wiki') . EOL);
			}

			$zip_folder_name = random_string(10);
			$zip_folderpath = '/tmp/' . $zip_folder_name;
			if(!mkdir($zip_folderpath, 0770, false)) {
				logger('Error creating zip file export folder: ' . $zip_folderpath, LOGGER_NORMAL);
				notice(t('Error creating zip file export folder') . EOL);
			}

			$zip_filename = $w['urlName'];
			$zip_filepath = '/tmp/' . $zip_folder_name . '/' . $zip_filename;

			// Generate the zip file
			ZLib\ExtendedZip::zipTree($w['path'], $zip_filepath, \ZipArchive::CREATE);

			// Output the file for download

			header('Content-disposition: attachment; filename="' . $zip_filename . '.zip"');
			header('Content-Type: application/zip');

			$success = readfile($zip_filepath);

			if(!$success) {
				logger('Error downloading wiki: ' . $resource_id);
				notice(t('Error downloading wiki: ' . $resource_id) . EOL);
			}

			// delete temporary files
			rrmdir($zip_folderpath);
			killme();

		}
*/
		switch(argc()) {
			case 2:
				$wikis = Zlib\NativeWiki::listwikis($owner, get_observer_hash());
				if($wikis) {
					$o .= replace_macros(get_markup_template('wikilist.tpl'), array(
						'$header' => t('Wikis'),
						'$channel' => $owner['channel_address'],
						'$wikis' => $wikis['wikis'],
						// If the observer is the local channel owner, show the wiki controls
						'$owner' => ((local_channel() && local_channel() === intval(\App::$profile['uid'])) ? true : false),
						'$edit' => t('Edit'),
						'$download' => t('Download'),
						'$view' => t('View'),
						'$create' => t('Create New'),
						'$submit' => t('Submit'),
						'$wikiName' => array('wikiName', t('Wiki name')),
						'$mimeType' => array('mimeType', t('Content type'), '', '', ['text/markdown' => 'Markdown', 'text/bbcode' => 'BB Code']),
						'$name' => t('Name'),
						'$type' => t('Type'),
						'$lockstate' => $x['lockstate'],
						'$acl' => $x['acl'],
						'$allow_cid' => $x['allow_cid'],
						'$allow_gid' => $x['allow_gid'],
						'$deny_cid' => $x['deny_cid'],
						'$deny_gid' => $x['deny_gid'],
						'$notify' => array('postVisible', t('Create a status post for this wiki'), '', '', array(t('No'), t('Yes')))
					));

					return $o;
				}
				break;

			case 3:

				// /wiki/channel/wiki -> No page was specified, so redirect to Home.md

				$wikiUrlName = urlencode(argv(2));
				goaway(z_root() . '/' . argv(0) . '/' . argv(1) . '/' . $wikiUrlName . '/Home');

			case 4:
			default:

				// GET /wiki/channel/wiki/page
				// Fetch the wiki info and determine observer permissions

				$wikiUrlName = urldecode(argv(2));

				$page_name = '';
				$ignore_language = false;

				for($x = 3; $x < argc(); $x ++) {
					if($page_name === '' && argv($x) === '-') {
						$ignore_language = true;
						continue;
					}
					if($page_name)
						$page_name .= '/';
            		$page_name .= argv($x);
				}

				$pageUrlName = urldecode($page_name);
				$langPageUrlName = urldecode(\App::$language . '/' . $page_name);

				$w = Zlib\NativeWiki::exists_by_name($owner['channel_id'], $wikiUrlName);

				if(! $w['resource_id']) {
					notice(t('Wiki not found') . EOL);
					goaway(z_root() . '/' . argv(0) . '/' . argv(1));
				}				

				$resource_id = $w['resource_id'];
				
				if(! $wiki_owner) {
					// Check for observer permissions
					$observer_hash = get_observer_hash();
					$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
					if(! $perms['read']) {
						notice(t('Permission denied.') . EOL);
						goaway(z_root() . '/' . argv(0) . '/' . argv(1));
						return; //not reached
					}
					$wiki_editor = (($perms['write']) ? true : false);
				}
				else {
					$wiki_editor = true;
				}

				$wikiheaderName = urldecode($wikiUrlName);
				$wikiheaderPage = urldecode($pageUrlName);

				$renamePage = (($wikiheaderPage === 'Home') ? '' : t('Rename page'));
				$p = [];

				if(! $ignore_language) {
					$p = Zlib\NativeWikiPage::get_page_content(array('channel_id' => $owner['channel_id'], 'observer_hash' => $observer_hash, 'resource_id' => $resource_id, 'pageUrlName' => $langPageUrlName));
				}
				if(! ($p && $p['success'])) {
					$p = Zlib\NativeWikiPage::get_page_content(array('channel_id' => $owner['channel_id'], 'observer_hash' => $observer_hash, 'resource_id' => $resource_id, 'pageUrlName' => $pageUrlName));
				}
				if(! ($p && $p['success'])) {
					notice( t('Error retrieving page content') . EOL);
					goaway(z_root() . '/' . argv(0) . '/' . argv(1) );
				}

				$mimeType = $p['mimeType'];

				$sampleContent = (($mimeType == 'text/bbcode') ? '[h3]' . t('New page') . '[/h3]' : '### ' . t('New page'));

				$content = (($p['content'] == '') ? $sampleContent : $p['content']);

				// Render the Markdown-formatted page content in HTML
				if($mimeType == 'text/bbcode') {
					$renderedContent = Zlib\NativeWikiPage::convert_links(zidify_links(smilies(bbcode($content))), argv(0) . '/' . argv(1) . '/' . $wikiUrlName);
				}
				else {
					$content = Zlib\MarkdownSoap::unescape($content);
					$html = Zlib\NativeWikiPage::generate_toc(zidify_text(MarkdownExtra::defaultTransform(Zlib\NativeWikiPage::bbcode($content))));
					$renderedContent = Zlib\NativeWikiPage::convert_links($html, argv(0) . '/' . argv(1) . '/' . $wikiUrlName);
				}
				$showPageControls = $wiki_editor;
				break;
//			default:	// Strip the extraneous URL components
//				goaway('/' . argv(0) . '/' . argv(1) . '/' . $wikiUrlName . '/' . $pageUrlName);
		}
		

		$wikiModalID = random_string(3);

		$wikiModal = replace_macros(get_markup_template('generic_modal.tpl'), array(
			'$id' => $wikiModalID,
			'$title' => t('Revision Comparison'),
			'$ok' => (($showPageControls) ? t('Revert') : ''),
			'$cancel' => t('Cancel')
		));

		$placeholder = t('Short description of your changes (optional)');
				
		$o .= replace_macros(get_markup_template('wiki.tpl'),array(
			'$wikiheaderName' => $wikiheaderName,
			'$wikiheaderPage' => $wikiheaderPage,
			'$renamePage' => $renamePage,
			'$showPageControls' => $showPageControls,
			'$editOrSourceLabel' => (($showPageControls) ? t('Edit') : t('Source')),
			'$tools_label' => 'Page Tools',
			'$channel' => $owner['channel_address'],
			'$resource_id' => $resource_id,
			'$page' => $pageUrlName,
			'$mimeType' => $mimeType,
			'$content' => $content,
			'$renderedContent' => $renderedContent,
			'$pageRename' => array('pageRename', t('New page name'), '', ''),
			'$commitMsg' => array('commitMsg', '', '', '', '', 'placeholder="' . $placeholder . '"'),
			'$wikiModal' => $wikiModal,
			'$wikiModalID' => $wikiModalID,
			'$commit' => 'HEAD',
			'$embedPhotos' => t('Embed image from photo albums'),
			'$embedPhotosModalTitle' => t('Embed an image from your albums'),
			'$embedPhotosModalCancel' => t('Cancel'),
			'$embedPhotosModalOK' => t('OK'),
			'$modalchooseimages' => t('Choose images to embed'),
			'$modalchoosealbum' => t('Choose an album'),
			'$modaldiffalbum' => t('Choose a different album'),
			'$modalerrorlist' => t('Error getting album list'),
			'$modalerrorlink' => t('Error getting photo link'),
			'$modalerroralbum' => t('Error getting album'),
		));

		if($p['mimeType'] != 'text/bbcode')
			head_add_js('/library/ace/ace.js');	// Ace Code Editor

		return $o;
	}

	function post() {

		require_once('include/bbcode.php');

		$nick = argv(1);
		$owner = channelx_by_nick($nick);
		$observer_hash = get_observer_hash();

		if(! $owner) {
			notice( t('Permission denied.') . EOL);
			return;
		}

		// /wiki/channel/preview
		// Render mardown-formatted text in HTML for preview
		if((argc() > 2) && (argv(2) === 'preview')) {
			$content = $_POST['content'];
			$resource_id = $_POST['resource_id'];
			$w = Zlib\NativeWiki::get_wiki($owner['channel_id'],$observer_hash,$resource_id);

			$wikiURL = argv(0) . '/' . argv(1) . '/' . $w['urlName'];

			$mimeType = $w['mimeType'];

			if($mimeType == 'text/bbcode') {
				$html = Zlib\NativeWikiPage::convert_links(zidify_links(smilies(bbcode($content))),$wikiURL);
			}
			else {
				$bb = Zlib\NativeWikiPage::bbcode($content);
				$x = new ZLib\MarkdownSoap($bb);
				$md = $x->clean();
				$md = ZLib\MarkdownSoap::unescape($md);
				$html = MarkdownExtra::defaultTransform($md);
				$html = Zlib\NativeWikiPage::generate_toc(zidify_text($html));
				$html = Zlib\NativeWikiPage::convert_links($html,$wikiURL);
			}
			json_return_and_die(array('html' => $html, 'success' => true));
		}
		
		// Create a new wiki
		// /wiki/channel/create/wiki
		if ((argc() > 3) && (argv(2) === 'create') && (argv(3) === 'wiki')) {

			// Only the channel owner can create a wiki, at least until we create a 
			// more detail permissions framework

			if (local_channel() !== intval($owner['channel_id'])) {
				goaway('/' . argv(0) . '/' . $nick . '/');
			} 
			$wiki = array(); 
			// Generate new wiki info from input name
			$wiki['postVisible'] = ((intval($_POST['postVisible'])) ? 1 : 0);
			$wiki['rawName']     = $_POST['wikiName'];
			$wiki['htmlName']    = escape_tags($_POST['wikiName']);
			$wiki['urlName']     = urlencode(urlencode($_POST['wikiName'])); 
			$wiki['mimeType']    = $_POST['mimeType'];

			if($wiki['urlName'] === '') {				
				notice( t('Error creating wiki. Invalid name.') . EOL);
				goaway('/wiki');
				return; //not reached
			}

			$exists = Zlib\NativeWiki::exists_by_name($owner['channel_id'], $wiki['urlName']);
			if($exists['id']) {
				notice( t('A wiki with this name already exists.') . EOL);
				goaway('/wiki');
				return; //not reached
			}

			// Get ACL for permissions
			$acl = new \Zotlabs\Access\AccessList($owner);
			$acl->set_from_array($_POST);
			$r = Zlib\NativeWiki::create_wiki($owner, $observer_hash, $wiki, $acl);
			if($r['success']) {
				Zlib\NativeWiki::sync_a_wiki_item($owner['channel_id'],$r['item_id'],$r['item']['resource_id']);
				$homePage = Zlib\NativeWikiPage::create_page($owner['channel_id'],$observer_hash,'Home', $r['item']['resource_id']);
				if(! $homePage['success']) {
					notice( t('Wiki created, but error creating Home page.'));
					goaway(z_root() . '/wiki/' . $nick . '/' . $wiki['urlName']);
				}
				Zlib\NativeWiki::sync_a_wiki_item($owner['channel_id'],$homePage['item_id'],$r['item']['resource_id']);
				goaway(z_root() . '/wiki/' . $nick . '/' . $wiki['urlName'] . '/' . $homePage['page']['urlName']);
			}
			else {
				notice( t('Error creating wiki'));
				goaway(z_root() . '/wiki');
			}
		}

		// Delete a wiki
		if ((argc() > 3) && (argv(2) === 'delete') && (argv(3) === 'wiki')) {

			// Only the channel owner can delete a wiki, at least until we create a 
			// more detail permissions framework
			if (local_channel() !== intval($owner['channel_id'])) {
				logger('Wiki delete permission denied.');
				json_return_and_die(array('message' => t('Wiki delete permission denied.'), 'success' => false));
			} 
			$resource_id = $_POST['resource_id']; 
			$deleted = Zlib\NativeWiki::delete_wiki($owner['channel_id'],$observer_hash,$resource_id);
			if ($deleted['success']) {
				Zlib\NativeWiki::sync_a_wiki_item($owner['channel_id'],$deleted['item_id'],$resource_id);
				json_return_and_die(array('message' => '', 'success' => true));
			} 
			else {
				logger('Error deleting wiki: ' . $resource_id . ' ' . $deleted['message']);
				json_return_and_die(array('message' => t('Error deleting wiki'), 'success' => false));
			}
		}


		// Create a page
		if ((argc() === 4) && (argv(2) === 'create') && (argv(3) === 'page')) {

			$resource_id = $_POST['resource_id']; 
			// Determine if observer has permission to create a page


			$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
			if(! $perms['write']) {
				logger('Wiki write permission denied. ' . EOL);
				json_return_and_die(array('success' => false));					
			}

			$name = $_POST['pageName']; //Get new page name
			if(urlencode(escape_tags($_POST['pageName'])) === '') {				
				json_return_and_die(array('message' => 'Error creating page. Invalid name.', 'success' => false));
			}
			$page = Zlib\NativeWikiPage::create_page($owner['channel_id'],$observer_hash, $name, $resource_id);

			if($page['item_id']) {
				$commit = Zlib\NativeWikiPage::commit(array(
					'commit_msg'    => t('New page created'), 
					'resource_id'   => $resource_id, 
					'channel_id'    => $owner['channel_id'],
					'observer_hash' => $observer_hash,
					'pageUrlName'   => $name
				));

				if($commit['success']) {
					Zlib\NativeWiki::sync_a_wiki_item($owner['channel_id'],$commit['item_id'],$resource_id);
					json_return_and_die(array('url' => '/' . argv(0) . '/' . argv(1) . '/' . urlencode($page['wiki']['urlName']) . '/' . urlencode($page['page']['urlName']), 'success' => true));
				} 
				else {
					json_return_and_die(array('message' => 'Error making git commit','url' => '/' . argv(0) . '/' . argv(1) . '/' . urlencode($page['wiki']['urlName']) . '/' . urlencode($page['page']['urlName']),'success' => false));
				}				


			}
			else {
				logger('Error creating page');
				json_return_and_die(array('message' => 'Error creating page.', 'success' => false));
			}
		}		
		
		// Fetch page list for a wiki
		if((argc() === 5) && (argv(2) === 'get') && (argv(3) === 'page') && (argv(4) === 'list')) {
			$resource_id = $_POST['resource_id']; // resource_id for wiki in db

			$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
			if(!$perms['read']) {
				logger('Wiki read permission denied.' . EOL);
				json_return_and_die(array('pages' => null, 'message' => 'Permission denied.', 'success' => false));					
			}

			// @FIXME - we shouldn't invoke this if it isn't in the PDL or has been over-ridden

			$x = new \Zotlabs\Widget\Wiki_pages();

			$page_list_html = $x->widget(array(
					'resource_id' => $resource_id, 
					'refresh' => true, 
					'channel' => argv(1)));
			json_return_and_die(array('pages' => $page_list_html, 'message' => '', 'success' => true));					
		}
		
		// Save a page
		if ((argc() === 4) && (argv(2) === 'save') && (argv(3) === 'page')) {
			
			$resource_id = $_POST['resource_id']; 
			$pageUrlName = $_POST['name'];
			$pageHtmlName = escape_tags($_POST['name']);
			$content = $_POST['content']; //Get new content
			$commitMsg = $_POST['commitMsg']; 
			if ($commitMsg === '') {
				$commitMsg = 'Updated ' . $pageHtmlName;
			}

			// Determine if observer has permission to save content
			$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
			if(! $perms['write']) {
				logger('Wiki write permission denied. ' . EOL);
				json_return_and_die(array('success' => false));					
			}
			
			$saved = Zlib\NativeWikiPage::save_page(array('channel_id' => $owner['channel_id'], 'observer_hash' => $observer_hash, 'resource_id' => $resource_id, 'pageUrlName' => $pageUrlName, 'content' => $content));

			if($saved['success']) {
				$commit = Zlib\NativeWikiPage::commit(array(
					'commit_msg' => $commitMsg, 
					'pageUrlName' => $pageUrlName,
					'resource_id' => $resource_id, 
					'channel_id'    => $owner['channel_id'],
					'observer_hash' => $observer_hash,
					'revision' => (-1)
				));
		
				if($commit['success']) {
					Zlib\NativeWiki::sync_a_wiki_item($owner['channel_id'],$commit['item_id'],$resource_id);
					json_return_and_die(array('message' => 'Wiki git repo commit made', 'success' => true));
				}
				else {
					json_return_and_die(array('message' => 'Error making git commit','success' => false));					
				}
			}
			else {
				json_return_and_die(array('message' => 'Error saving page', 'success' => false));					
			}
		}
		
		// Update page history
		// /wiki/channel/history/page
		if ((argc() === 4) && (argv(2) === 'history') && (argv(3) === 'page')) {
			
			$resource_id = $_POST['resource_id'];
			$pageUrlName = $_POST['name'];
			
			// Determine if observer has permission to read content

			$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
			if(! $perms['read']) {
				logger('Wiki read permission denied.' . EOL);
				json_return_and_die(array('historyHTML' => '', 'message' => 'Permission denied.', 'success' => false));
			}

			$historyHTML = \Zotlabs\Lib\NativeWikiPage::render_page_history(array(
				'resource_id' => $resource_id,
				'pageUrlName' => $pageUrlName,
				'permsWrite'  => $perms['write']
			));

			json_return_and_die(array('historyHTML' => $historyHTML, 'message' => '', 'success' => true));
		}

		// Delete a page
		if ((argc() === 4) && (argv(2) === 'delete') && (argv(3) === 'page')) {

			$resource_id = $_POST['resource_id']; 
			$pageUrlName = $_POST['name'];

			if ($pageUrlName === 'Home') {
				json_return_and_die(array('message' => t('Cannot delete Home'),'success' => false));
			}
			// Determine if observer has permission to delete pages
			// currently just allow page owner

			if((! local_channel()) || (local_channel() != $owner['channel_id'])) {
				logger('Wiki write permission denied. ' . EOL);
				json_return_and_die(array('success' => false));					
			}

			$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
			if(! $perms['write']) {
				logger('Wiki write permission denied. ' . EOL);
				json_return_and_die(array('success' => false));					
			}

			$deleted = Zlib\NativeWikiPage::delete_page(array('channel_id' => $owner['channel_id'], 'observer_hash' => $observer_hash, 'resource_id' => $resource_id, 'pageUrlName' => $pageUrlName));
			if($deleted['success']) {
				Zlib\NativeWiki::sync_a_wiki_item($owner['channel_id'],$commit['item_id'],$resource_id);
				json_return_and_die(array('message' => 'Wiki git repo commit made', 'success' => true));
			}
			else {
				json_return_and_die(array('message' => 'Error deleting page', 'success' => false));					
			}
		}
		
		// Revert a page
		if ((argc() === 4) && (argv(2) === 'revert') && (argv(3) === 'page')) {

			$resource_id = $_POST['resource_id']; 
			$pageUrlName = $_POST['name'];
			$commitHash = $_POST['commitHash'];
			// Determine if observer has permission to revert pages

			$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
			if(! $perms['write']) {
				logger('Wiki write permission denied.' . EOL);
				json_return_and_die(array('success' => false));					
			}

			$reverted = Zlib\NativeWikiPage::revert_page(array('channel_id' => $owner['channel_id'], 'observer_hash' => $observer_hash, 'commitHash' => $commitHash, 'resource_id' => $resource_id, 'pageUrlName' => $pageUrlName));
			if($reverted['success']) {
				json_return_and_die(array('content' => $reverted['content'], 'message' => '', 'success' => true));					
			} else {
				json_return_and_die(array('content' => '', 'message' => 'Error reverting page', 'success' => false));					
			}
		}
		
		// Compare page revisions
		if ((argc() === 4) && (argv(2) === 'compare') && (argv(3) === 'page')) {
			$resource_id = $_POST['resource_id']; 
			$pageUrlName = $_POST['name'];
			$compareCommit = $_POST['compareCommit'];
			$currentCommit = $_POST['currentCommit'];
			// Determine if observer has permission to revert pages

			$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
			if(!$perms['read']) {
				logger('Wiki read permission denied.' . EOL);
				json_return_and_die(array('success' => false));					
			}

			$compare = Zlib\NativeWikiPage::compare_page(array('channel_id' => $owner['channel_id'], 'observer_hash' => $observer_hash, 'currentCommit' => $currentCommit, 'compareCommit' => $compareCommit, 'resource_id' => $resource_id, 'pageUrlName' => $pageUrlName));
			if($compare['success']) {
				$diffHTML = '<table class="text-center" width="100%"><tr><td class="lead" width="50%">' . t('Current Revision') . '</td><td class="lead" width="50%">' . t('Selected Revision') . '</td></tr></table>' . $compare['diff'];
				json_return_and_die(array('diff' => $diffHTML, 'message' => '', 'success' => true));					
			} else {
				json_return_and_die(array('diff' => '', 'message' => 'Error comparing page', 'success' => false));					
			}
		}
		
		// Rename a page
		if ((argc() === 4) && (argv(2) === 'rename') && (argv(3) === 'page')) {
			$resource_id = $_POST['resource_id']; 
			$pageUrlName = $_POST['oldName'];
			$pageNewName = $_POST['newName'];
			if ($pageUrlName === 'Home') {
				json_return_and_die(array('message' => 'Cannot rename Home','success' => false));
			}
			if(urlencode(escape_tags($pageNewName)) === '') {				
				json_return_and_die(array('message' => 'Error renaming page. Invalid name.', 'success' => false));
			}
			// Determine if observer has permission to rename pages

			$perms = Zlib\NativeWiki::get_permissions($resource_id, intval($owner['channel_id']), $observer_hash);
			if(! $perms['write']) {
				logger('Wiki write permission denied. ' . EOL);
				json_return_and_die(array('success' => false));					
			}

			$renamed = Zlib\NativeWikiPage::rename_page(array('channel_id' => $owner['channel_id'], 'observer_hash' => $observer_hash, 'resource_id' => $resource_id, 'pageUrlName' => $pageUrlName, 'pageNewName' => $pageNewName));

			if($renamed['success']) {
				$commit = Zlib\NativeWikiPage::commit(array(
					'channel_id' => $owner['channel_id'],
					'commit_msg' => 'Renamed ' . urldecode($pageUrlName) . ' to ' . $renamed['page']['htmlName'], 
					'resource_id' => $resource_id, 
					'observer_hash' => $observer_hash,
					'pageUrlName' => $pageNewName
				));
				if($commit['success']) {
					Zlib\NativeWiki::sync_a_wiki_item($owner['channel_id'],$commit['item_id'],$resource_id);
					json_return_and_die(array('name' => $renamed['page'], 'message' => 'Wiki git repo commit made', 'success' => true));
				}
				else {
					json_return_and_die(array('message' => 'Error making git commit','success' => false));					
				}
			}
			else {
				json_return_and_die(array('message' => 'Error renaming page', 'success' => false));					
			}
		}

		//notice( t('You must be authenticated.'));
		json_return_and_die(array('message' => t('You must be authenticated.'), 'success' => false));
		
	}
}