Multisite.module

<?php

/**
 *
 * Multisite module for Processwire
 * Inspired by Multisite module made by authors: Ryan, Antti Peisa, Avoine Oy, Philipp "Soma" Urlich
 *
 * complete rewrite of the original and forked modules
 *
 * @author Christoph Thelen aka @kixe 2017/03/25
 * @copyright © 2017 Christoph Thelen
 * @license Licensed under MIT, see LICENSE.txt
 * @link https://processwire.com/talk/topic/...
 * @version 2.0.2
 * @since 1.0.0 init - 2017/05/09
 * @since 1.0.1 default rootpage, domain related access control for MultisitePageTree, fixed path bug - 2017/05/10
 * @since 1.0.2 fixed root page path issue in single language mode FORCE $page->template->slashUrls for rootPage - 2017/05/10
 * @since 1.0.3 fixed issue other language rootPageName, let hook modify Page view urls in admin too, take in account slashUrl and useHomeSegment settings - 2017/05/13
 * @since 1.0.4 show warning if hooked methods are not hookable - 2017/06/22
 * @since 2.0.0 major upgrade, root page of any MultisitePageTree can be placed elsewhere in the pagetree - 2018/01/26
 * @since 2.0.1 bugfixes - 2018/01/28
 * @since 2.0.2 support of redirects if defined in config, bugfixes - 2018/02/07
 * @todo
 * - modify ProcessPageList::executeNavJSON() Change $parentID from hardcoded 1 to $config->rootPageID to get proper results Pages > Tree
 * - make hookable core function LanguageSupportPageNames::getPagePath() for proper language support
 * - make hookable core function AdminRestrictBranch::getBranchRootParentId() to get it working together
 *
 * FEATURES
 * - multilanguage support
 * - LanguageSupportPageName::useHomeSegment support
 * - slashUrl support 
 * - domain related homepage and custom 404 is set by id
 * - no restriction about domain and page naming, even multilanguage
 * - path modification is done by hooks
 * - auto modification of view links in backend
 * - domain related access control of MultiSiteTree (shows 404 if doesn't match)
 * - root page of a Multisite page tree can be placed elsewhere in the ProcessWire page tree
 * - Support of redirects
 *
 * REQUIREMENTS MULTILANGUAGE
 * LanguageSupportPageNames installed
 * LanguageSupportPageNames::getPagePath() MUST BE MODIFIED hookable in core
 * a page name for the default language and any other language must be set for the superRoot page ($page->id = 1)
 *
 * SETUP
 * in config.php
 * $config->MultisiteDomains = array(
 *		"example.com" => array( // domain name is used to map to root page allow subdomains
 *       	"root" => 1026, // int $page->id of the root page or redirect url starting with http
 *			"http404" => 27 // int page->id of custom 404 error page (optionally)
 *      ),
 * );
 *
 *
 * $config->httpHosts = array_unique(array_merge($config->httpHosts, array_keys($config->MultisiteDomains)));
 */

class Multisite extends WireData implements Module {

	// set by constructor
	protected $domains = array(); // settings array $config->MultisiteDomains
	protected $domain = null; // null/string $config->httpHost if item key of $config->MultisiteDomains
	public $rootPageID = 1; // page id of root page related to domain
	protected $languageSupport = false; // runtime true if LanguageSupportPageNames is installed
	protected $useHomeSegment = "0"; // string "0" or "1" runtime LanguageSupportPageNames::useHomeSegment
	protected $it = ''; // string sanitized $_GET['it'] if set

	// set by init()
	protected $rootPage = null; // page object, instance of root page related to domain
	protected $rootPagePath = ''; // language sensitive page path of root page (related to domain)
	protected $language = null; // request is default language
	protected $homeSegment = ''; // 
	protected $page = null; // page object, page to be rendered
	protected $redirectPage = null;
	protected $isAdmin = false;

	public static function getModuleInfo() {
		return array(
			'title' => 'Multisite',
			'version' => 202,
			'summary' => 'Allows multiple sites with different domains run from single PW-site and database.',
			'href' => 'https://github.com/kixe/Multisite',
			'singular' => true,
			'autoload' => true
			);
	}

	public function __construct() {
		// read config settings
		if(!empty($this->wire("config")->MultisiteDomains)) $this->domains = $this->wire("config")->MultisiteDomains;
		if (array_key_exists($this->wire('config')->httpHost, $this->domains)) {
			$this->domain = $this->wire('config')->httpHost;
			if (!array_key_exists('root', $this->domains[$this->domain])) throw new WireException("\$config->MultisiteDomains[$this->domain]['root'] not set");
			$root = $this->domains[$this->domain]['root'];
			if (strpos($root, 'http://') === 0 || strpos($root, 'https://') === 0) $this->redirectPage = $root;
			else if (!is_numeric($root)) throw new WireException("Wrong type for \$config->MultisiteDomains[$this->domain]['root']. Use int.");
			$this->rootPageID = (int) $root;

			// language support
			if ($this->wire('modules')->isInstalled('LanguageSupportPageNames')) {
				$this->languageSupport = true;
				$namespace = (ProcessWire::versionMajor == 3)? 'ProcessWire\\':'';
				if (!method_exists("{$namespace}LanguageSupportPageNames", '___getPagePath')) $this->warning('LanguageSupportPageNames::getPagePath() is not hookable');
			}
			
			// This module works properly together with AdminRestrictBranch if getBranchRootParentId() is modified and hookable
			if ($this->wire('modules')->isInstalled('AdminRestrictBranch')) {
				if (method_exists('AdminRestrictBranch', '___getBranchRootParentId')) {
				$this->addHookAfter('AdminRestrictBranch::getBranchRootParentId', function($e) {
						$e->return = $this->rootPageID;
					});
				} else $this->warning('AdminRestrictBranch::getBranchRootParentId() is not hookable');
			}

			// sanitize $_GET['it']
			if (isset($_GET['it'])) $this->it = $this->wire('sanitizer')->path($_GET['it']);
		}
	}

	public function init() {
		// quick exit
		if(empty($this->domains) || $this->domain == null || $this->rootPageID == 1) return;

		// redirect if set
		if ($this->redirectPage) $this->wire('session')->redirect($this->redirectPage);

		// settings ok?
		$this->configCheck($this->domain);

		// set custom http 404 page
		if (isset($this->domains[$this->domain]['http404'])) $this->wire("config")->http404PageID = $this->domains[$this->domain]['http404'];

		$superRootURL = $this->wire('config')->urls->root; // could be '/' or '/subfolder/'

		// if it's /site/ folder exit
		if(strpos($superRootURL . $this->it, $this->wire('config')->urls->site) === 0) return;

		// if it's /wire/ folder exit
		if(strpos($superRootURL . $this->it, $this->wire('config')->urls->wire) === 0) return;

		// if it's form-builder exit
		if(strpos($superRootURL . $this->it, "/form-builder/") !== false) return;

		// if called from PW front-end editing exit
		if($this->wire("input")->post->action == "PageFrontEditSave") return;

		// set root page
		$this->rootPage = $this->wire('pages')->get($this->rootPageID);

		// modify $_GET['it'] if not admin
		if(strpos($superRootURL . trim($this->it, '/') . '/', $this->wire('config')->urls->admin) !== 0) {

			if ($this->languageSupport) {
				$this->useHomeSegment = $this->wire('modules')->get('LanguageSupportPageNames')->useHomeSegment;
				$this->language = $this->wire('languages')->getDefault();
				$it = array_filter(explode('/',$this->it));
				$homeSegment = (empty($it))? $this->getHomeSegment() : $this->getHomeSegment($it[0]);
			}

			// get rootPagePath in requested language
			$this->rootPagePath = $this->getPagePathSegment($this->rootPage, $this->wire('pages')->get(1), $this->language);

			if ($this->languageSupport) {
				if ($homeSegment && empty($it)) array_unshift($it, $homeSegment);
				array_splice($it, 1, 0, $this->rootPagePath); // multi language - splice in at position 1
				$it = implode('/',$it);
			}
			else $it = "$this->rootPagePath/$this->it"; // case single language - just prepend

			// get requested page and update slash
			$this->page = $this->wire('pages')->get("path=/".trim($it,'/').'/');

			$slash = ($this->page->id && $this->page->template->slashUrls)? '/' : '';

			// redirect if $_GET['it'] doesn't match LanguageSupportPageNames::useHomeSegment setting
			if ($this->languageSupport && $this->language->isDefault() && $this->rootPage == $this->page) {
				if ($this->useHomeSegment && $this->it != $homeSegment.$slash) $this->wire('session')->redirect("/$homeSegment$slash");
				if (!$this->useHomeSegment && $this->it == $homeSegment.$slash) $this->wire('session')->redirect("/");
			}

			// redirect if $_GET['it'] doesn't match $page->template->slashUrls setting
			if ($this->it) {
				if ($slash && substr($this->it, -1) != '/') $this->wire('session')->redirect("/$this->it/");
				if (!$slash && $this->page->id && substr($this->it, -1) == '/')  $this->wire('session')->redirect("/".rtrim($this->it,'/'));
			}

			$_GET['it'] = trim($it,'/').$slash;
		}
		
		// add path hook
		$this->addHookBefore('Page::render', $this, 'hookPageRender');
	}

	/**
	 * Disallow access of pages residing in a MultisitePageTree for domains other than the corresponding root page
	 * @todo obsolete?
	 *
	public function ready() {
		if ($this->wire('user')->isSuperuser()) return;
		$pageTreeIDs = $this->wire('page')->parents()->each('id');
		$pageTreeIDs[] = $this->wire('page')->id;
		$multisiteRootIDs = array_map(function($i) { return $i = $i['root']; }, $this->domains);
		$matches = array_intersect($multisiteRootIDs, $pageTreeIDs);
		if ($this->wire('page')->id == $this->wire("config")->http404PageID || empty($matches)) return;
		reset($matches);
		if (in_array($this->domain, array_keys($matches))) return;
		$view = new ProcessPageView();	
		$view->pageNotFound($this->wire('page'), $this->it, true, 'access not allowed');
	}
	*/

	/**
	 * Hook Page::render hooks Page::path and LanguageSupportPageNames::getPagePath
	 *
	 * @param HookEvent $e
	 * @see hookPagePath()
	 * @todo make hookable LanguageSupportPageNames::getPagePath
	 */
	protected function hookPageRender(HookEvent $e) {
		if ($this->languageSupport) $this->addHookAfter('LanguageSupportPageNames::getPagePath', $this, 'hookPagePath');
		else $this->addHookAfter('Page::path', $this, 'hookPagePath');
	}

	/**
	 * Hook is called from hookPageRender()
	 * modifies $page->url, $page->httpUrl, $page->path, $page->localPath() $page->localUrl(), $page->localHttpUrl()
	 * modifies page view urls ProcessPageListActions::getActions ProcessPageEdit::buildFormView
	 * @param  HookEvent $e
	 * @see hookPageRender(),
	 */
	protected function hookPagePath(HookEvent $e) {

		$page = isset($e->arguments[0])? $e->arguments[0] : $e->object;
		if ($page->id == 1) return;
		$language = isset($e->arguments[1])? $e->arguments[1] : '';
		$cut = $this->getPagePathSegment($this->rootPage, $this->wire('pages')->get(1), $language);
		if ($cut === false) return;

		// special case multilanguage + homepage
		if ($language && $page == $this->rootPage) {
			$homeSegment = $this->getHomeSegment($language);
			$useHomeSegment = $this->wire('modules')->get('LanguageSupportPageNames')->useHomeSegment;
			if ($language instanceof Language && $language->isDefault() && $useHomeSegment == '0') $e->return = '/';
			else $e->return = $page->template->slashUrls? "/$homeSegment/" : "/$homeSegment";
		}

		else if (strlen($cut) && strpos($e->return, "$cut/")) $e->return = str_replace("$cut/", '', $e->return);
	}

	/**
	 * get or verify homeSegment by name or language id or object
	 * compares given string argument with name of root page (homeSegment)
	 * modifies property language on success
	 * @param  string|int|object $langIndicator
	 * @return bool|string $homeSegment
	 */
	protected function getHomeSegment($langIndicator = '') {
		if (!$this->languageSupport) return '';
		if (is_string($langIndicator) && strlen($langIndicator)) {
			foreach($this->wire('languages') as $language) {
				$pageName = $this->wire('pages')->get(1)->get("name$language|name");
				if ($pageName === $langIndicator) {
					// verified!
					$this->language = $language;
					return $pageName;
				}
			}
		}
		$pageName = $this->wire('pages')->get(1)->get("name$langIndicator|name");
		if ($pageName == Pages::defaultRootName) return '';
		return $pageName;
	}

	/**
	 * get a language sensitive path segment between two pages lacking homeSegment, leading and trailing slashes
	 * @param Page object $to
	 * @param Page object $from
	 * @param null|Language object $language
	 * @return string e.g. name/name/name
	 */
	protected function getPagePathSegment(Page $to, Page $from, $language = '') {
		
		if($to == $from) return '';	
		if (!$to->parents()->has($from)) return false;

		// default language or single language environment
		$isDefault = true;
		if ($this->languageSupport && $language instanceof Language) $isDefault = $language->isDefault();

		$path = array();
		$pages = $to->parentsUntil($from)->append($to);
		foreach($pages as $page) {
			$name = $isDefault ? $page->name : $page->get("name$language|name");
			if (strlen($name)) $path[] = $name;
		}

		return implode($path,'/');
	}

	/**
	 * check existence and accessibility of pages defined in config settings
	 * @param  string $domain
	 * @throws Exception
	 */
	protected function configCheck($domain) {
		foreach ($this->domains[$domain] as $key => $id) {
			if (!is_int($id)) throw new WireException(sprintf("Expecting integer value (\$page->id). %s given. Check \$config->MultisiteDomains['$domain']['$key'].", $id));
			$page = $this->wire('pages')->get($id);
			if ($page instanceof NullPage) throw new WireException(sprintf("The page with ID = %s doesn't exist. Check \$config->MultisiteDomains['$domain']['$key'].", $id));
		}
	}
}