<?php
/**
 * @package sapphire
 * @subpackage core
 */

/**
 * Basic data-object representing all pages within the site tree.
 * This data-object takes care of the heirachy.  All page types that live within the heirachy
 * should inherit from this.  
 * 
 * In addition, it contains a number of static methods for querying the site tree.
 */
class SiteTree extends DataObject {
	/**
	 * Get the URL for this page.
	 * @param string $action An action to include in the link
	 * @return string The URL for this page
	 */
	public function Link($action = null) {
		if($action == "index") {
			$action = "";
		}		
		return Director::baseURL() . $this->URLSegment . "/$action";
	}
		
	/**
	 * Returns link/current, depending on whether you're on the current page.
	 * This is useful for css styling of menus.
	 * @return string Either 'link' or 'current'.
	 */
	public function LinkOrCurrent() {
		return $this->isCurrent() ? "current" : "link";
	}
	
	/**
	 * Returns link/section, depending on whether you're on the current section.
	 * This is useful for css styling of menus.
	 * @return string Either 'link' or 'section'.
	 */
	public function LinkOrSection() {
		return $this->isSection() ? "section" : "link";
	}
	
	/**
	 * Returns link/current/section, depending if you're not in the current section,
	 * you're on the current page, or you're in the current section
	 * but not on the current page.
	 * @return string Either 'link', 'current' or 'section'.
	 */
	public function LinkingMode() {
		$this->prepareCurrentAndSection();
		
		if($this->ID == self::$currentPageID) {
			return "current";
		} else if(in_array($this->ID, self::$currentSectionIDs)) {
			return "section";
		} else {
			return "link";
		}
	}
	
	/**
	 * Get the URL segment for this page, eg 'home'
	 * @return string The URL segment
	 */
	public function ElementName() {
		return $this->URLSegment;
	}

	/**
	 * Check if this page is in the given current section.
	 * @param string $sectionName Name of the section to check.
	 * @return boolean True if we are in the given section.
	 */
	public function InSection($sectionName) {
		$page = Director::currentPage();
		while($page) {
			if($sectionName == $page->URLSegment) return true;
			$page = $page->Parent;
		}
		return false;
	}
	
	/**
	 * Returns comments on this page. This will only show comments that
	 * have been marked as spam if "?showspam=1" is appended to the URL.
	 * @return DataObjectSet Comments on this page.
	 */
	public function Comments() {
		if(isset($_GET['showspam'])) {
			$comments =  DataObject::get("PageComment", "ParentID = '" . Convert::raw2sql($this->ID) . "'", "Created DESC");
		} else {
			$comments = DataObject::get("PageComment", "ParentID = '" . Convert::raw2sql($this->ID) . "' AND IsSpam = 0", "Created DESC");
		}
		
		return $comments ? $comments : new DataObjectSet();
	}
	
	/**
	 * Create a duplicate of this node. Doesn't affect joined data - create a custom overloading of this
	 * if you need such behaviour.
	 * @return SiteTree The duplicated object.
	 */
	 public function duplicate() {
		$page = parent::duplicate();
		$page->CheckedPublicationDifferences = $page->AddedToStage = true;
		return $page;
	}
	
	/**
	 * Duplicates each child of this node recursively and returns the duplicate node.
	 * @return SiteTree The duplicated object.
	 */
	public function duplicateWithChildren() {
		$clone = $this->duplicate();
		$children = $this->AllChildren();

		if($children) {
			foreach($children as $child) {
				$childClone = method_exists( $child, 'duplicateWithChildren' ) ? $child->duplicateWithChildren() : $child->duplicate();
				$childClone->ParentID = $clone->ID;
				$childClone->write();
			}
		}
		
		return $clone;
	}
	
	/**
	 * Duplicate this node and its children as a child of the node with the given id
	 * @param int $id ID of the new node's new parent
	 */
	public function duplicateAsChild( $id ) {
		$newSiteTree = $this->duplicate();
		$newSiteTree->ParentID = $id;
		$newSiteTree->write();
	}
	
	/**
	 * An array of this pages URL segment and it's parents.
	 * This is generated by prepareCurrentAndSection for use by
	 * isCurrent() and isSection()
	 * @var array
	 */
	protected static $currentSectionIDs;
	/**
	 * The current page ID.
	 * This is generated by prepareCurrentAndSection for use by
	 * isCurrent() and isSection()
	 * @var int
	 */
	protected static $currentPageID;
	
	/**
	 * This function is used for isCurrent() and isSection() to prepare
	 * the cached answers.
	 */
	protected function prepareCurrentAndSection() {
		if(!self::$currentPageID) {
			self::$currentPageID = Director::currentPage() ? Director::currentPage()->ID : null;
			if(!isset(self::$currentPageID)) {
				self::$currentPageID = -1;
				$nextID = isset(Director::currentPage()->Parent->ID) ? Director::currentPage()->Parent->ID : null;
			} else {
				$nextID = SiteTree::$currentPageID;
			}
			
			$table = (Versioned::current_stage() == "Live") ? "SiteTree_Live" : "SiteTree";

			SiteTree::$currentSectionIDs = array();
			while($nextID) {
				self::$currentSectionIDs[] = $nextID;
				$nextID = DB::query("SELECT ParentID FROM SiteTree WHERE ID = $nextID")->value();
			}
		}
	}
	
	/**
	 * Check if this is the currently viewed page.
	 * @return boolean True if this is the current page.
	 */
	public function isCurrent() {
		$this->prepareCurrentAndSection();
		return $this->ID == SiteTree::$currentPageID;
	}
	
	/**
	 * Check if the currently viewed page is in this section.
	 * @return boolean True if the currently viewed page is in this section.
	 */
	public function isSection() {
		$this->prepareCurrentAndSection();
		return in_array($this->ID, self::$currentSectionIDs);
	}
	
	/**
	 * Return a breadcrumb trail to this page.
	 * @param int $maxDepth The maximum depth to traverse.
	 * @param boolean $unlinked Do not make page names links
	 * @param string $stopAtPageType ClassName of a page to stop the upwards traversal.
	 * @return string The breadcrumb trail.
	 */
	public function Breadcrumbs($maxDepth = 20, $unlinked = false, $stopAtPageType = false) {
		$page = $this;
		$parts = array();
		$i = 0;
		while(($page && (sizeof($parts) < $maxDepth))	|| ($stopAtPageType && $page->ClassName != $stopAtPageType)) {
			if($page->ShowInMenus || ($page->ID == $this->ID)) {
				if($page->URLSegment == 'home') {
					$hasHome = true;
				}
				$parts[] = (($page->ID == $this->ID) || $unlinked) ? Convert::raw2xml($page->Title) : ("<a href=\"" . $page->Link() . "\">" . Convert::raw2xml($page->Title) . "</a>");
			}
			$page = $page->Parent;
		}
		
		return implode(" &raquo; ", array_reverse($parts));
	}
	
	/**
	 * Get the parent of this page.
	 * @return SiteTree Parent of this page.
	 */
	public function getParent() {
		if($this->getField("ParentID"))
			return DataObject::get_one("SiteTree", "`SiteTree`.ID = " . $this->getField("ParentID"));
	}
	
	/**
	 * Make this page a child of another page.
	 * @param SiteTree|int $item Either the parent object, or the parent id
	 */
	public function setParent($item) {
		if(is_object($item)) {
			$this->setField("ParentID", $item->ID);
		} else {
			$this->setField("ParentID", $item);
		}
	}
	
	/**
	 * Return a string of the form "parent - page" or "grandparent - parent - page".
	 * @param int $level The maximum amount of levels to traverse.
	 * @param string $seperator Seperating string
	 * @return string The resulting string
	 */
	function NestedTitle($level = 2, $separator = " - ") {
		$item = $this;
		while($item && $level > 0) {
			$parts[] = $item->Title;
			$item = $item->Parent;
			$level--;
		}
		return implode($separator, array_reverse($parts));
	}
	
	/** 
	 * Returns true if the member is allowed to do the given action.
	 *
	 * @param string $perm The permission to be checked, such as 'View'.
	 * @param Member $member The member whose permissions need checking.
	 *                       Defaults to the currently logged in user.
	 *
	 * @return boolean True if the the member is allowed to do the given
	 *                 action.
	 *
	 * @todo Check we get a endless recursion if we use parent::can()
	 */
	function can($perm, $member = null) {
		if(!isset($member)) {
			$member = Member::currentUser();
		}
		
		// Users with ADMIN permission can always do this
		if($member && Permission::check('ADMIN')) {
			return true;
		}

		switch(strtolower($perm)) {
			case 'edit':
				if($this->Editors == 'LoggedInUsers' && $member) return true;
				if($member && $this->Editors == 'OnlyTheseUsers' && $member->isInGroup($this->EditorsGroup)) return true;
			break;
			case 'view':
			case 'view_page':
				if($this->Viewers == 'Anyone') return true;
				if($member && $this->Viewers == 'LoggedInUsers') return true;
				if($member && $this->Viewers == 'OnlyTheseUsers' && $member->isInGroup($this->ViewersGroup)) return true;
			break;
		}

		return false;
	}


	/**
	 * This function should return true if the current user can add children
	 * to this page.
	 *
	 * It can be overloaded to customise the security model for an
	 * application.
	 *
	 * @return boolean True if the current user can add children.
	 */
	public function canAddChildren() {
		return $this->canEdit() && $this->stat('allowed_children') != 'none';
	}
	
	/**
	 * This function should return true if the current user can delete this page.
	 * It can be overloaded to customise the security model for an application.
	 * @return boolean True if the current user can delete this page.
	 */
	public function canDelete() {
		return $this->stat('can_create') != false; 
	}
	
	/**
	 * This function should return true if the current user can create new pages of this class.
	 * It can be overloaded to customise the security model for an application.
	 * @return boolean True if the current user can create pages on this class.
	 */
	public function canCreate() {
		return $this->stat('can_create') != false || Director::isDev(); 
	}
	
	/**
	 * This function should return true if the current user can edit this page.
	 * It can be overloaded to customise the security model for an application.
	 * @return boolean True if the current user can edit this page.
	 */
	public function canEdit() {
		return $this->can('Edit');
	}

	/**
	 * This function should return true if the current user can publish this page.
	 * It can be overloaded to customise the security model for an application.
	 * @return boolean True if the current user can publish this page.
	 */
	public function canPublish() {
		return $this->canEdit();
	}
	
	/**
	 * Collate selected descendants of this page. 
	 * $condition will be evaluated on each descendant, and if it is succeeds, that item will be added
	 * to the $collator array.
	 * @param string $condition The PHP condition to be evaluated.  The page will be called $item
	 * @param array $collator An array, passed by reference, to collect all of the matching descendants.
	 */
	public function collateDescendants($condition, &$collator) {
		if($children = $this->Children()) {
			foreach($children as $item) {
				if(eval("return $condition;")) $collator[] = $item;
				$item->collateDescendants($condition, $collator);
			}
			return true;
		}
	}
	
	/**
	 * Return the title, description and keywords metatags.
	 * @param boolean $includeTitle Show default <title>-tag, set to false for custom templating
	 * @return string The XHTML metatags
	 */
	public function MetaTags($includeTitle = true) {
		$tags = "";
		if($includeTitle == true) {
			$tags .= "<title>" . Convert::raw2xml($this->MetaTitle ? $this->MetaTitle : $this->Title) . "</title>\n";
		}
		$tags .= "<meta name=\"generator\" http-equiv=\"generator\" content=\"SilverStripe 2.0 - http://www.silverstripe.com\" />\n";
		
		$charset = ContentNegotiator::get_encoding();
		$tags .= "<meta http-equiv=\"Content-type\" content=\"text/html; charset=$charset\" />\n";
		if($this->MetaKeywords) {
			$tags .= "<meta name=\"keywords\" http-equiv=\"keywords\" content=\"" . Convert::raw2att($this->MetaKeywords) . "\" />\n";
		}
		if($this->MetaDescription) {
			$tags .= "<meta name=\"description\" http-equiv=\"description\" content=\"" . Convert::raw2att($this->MetaDescription) . "\" />\n";
		}

		return $tags;
	}
	
	/**
	 * Returns the object that contains the content that a user would associate with this page.
	 * Ordinarily, this is just the page itself, but for example on RedirectorPages or VirtualPages
	 * ContentSource() will return the page that is linked to.
	 * @return SiteTree The content source.
	 */
	public function ContentSource() {
		return $this;
	}
	
	function requireDefaultRecords() {
		parent::requireDefaultRecords();
		
		if(!DataObject::get_one("SiteTree", "URLSegment = 'home'")) {
			$homepage = new Page();
			$homepage->Title = "Home";
			$homepage->Content = "<p>Welcome to SilverStripe! This is the default homepage. You can edit this page by opening <a href=\"admin/\">the CMS</a>.</p>";
			$homepage->URLSegment = "home";
			$homepage->Status = "Published";
			$homepage->write();
			$homepage->publish("Stage", "Live");
			
			if(!Database::$supressOutput) {
				echo "<li style=\"color: orange\">Home page created</li>";
			}
		}
		
		if(DB::query("SELECT COUNT(*) FROM SiteTree")->value() == 1) {
			$aboutus = new Page();
			$aboutus->Title = "About Us";
			$aboutus->Content = "<p>You can fill this page out with your own content, or delete it and create your own pages.<br /></p>";
			$aboutus->URLSegment = "about-us";
			$aboutus->Status = "Published";
			$aboutus->write();
			$aboutus->publish("Stage", "Live");
			
			if(!Database::$supressOutput) {
				echo "<li style=\"color: orange\">About Us created</li>";
			}
			
			$contactus = new Page();
			$contactus->Title = "Contact Us";
			$contactus->Content = "<p>You can fill this page out with your own content, or delete it and create your own pages.<br /></p>";
			$contactus->URLSegment = "contact-us";
			$contactus->Status = "Published";
			$contactus->write();
			$contactus->publish("Stage", "Live");
		}
		

	}

	//------------------------------------------------------------------------------------//

	protected function onBeforeWrite() {
		if(!$this->Sort && $this->ParentID) {
			$this->Sort = DB::query("SELECT MAX(Sort) + 1 FROM SiteTree WHERE ParentID = $this->ParentID")->value();
		}
		
		// Auto-set URLSegment
		if((!$this->URLSegment || $this->URLSegment == 'new-page') && $this->Title) {
			$this->URLSegment = $this->generateURLSegment($this->Title);
			
		// Keep it clean
		} else if(isset($this->changed['URLSegment']) && $this->changed['URLSegment']) {
			$segment = ereg_replace('[^A-Za-z0-9]+','-',$this->URLSegment);
			$segment = ereg_replace('-+','-',$segment);
			if(!$segment) {
				$segment = "page-$this->ID";
			}
			$this->URLSegment = $segment;
		}
		
		// Ensure URLSegment is unique
		$idFilter = $this->ID ? " AND `SiteTree`.ID <> '$this->ID'" : '';
		$count = 1;
		while(DataObject::get_one("SiteTree", "URLSegment = '$this->URLSegment' $idFilter")) {
			$count++;
			$this->URLSegment = ereg_replace('-[0-9]+','', $this->URLSegment) . "-$count";
		}
		
		// If the URLSegment has been changed, rewrite links
		if(isset($this->changed['URLSegment']) && $this->changed['URLSegment']) {
			if($this->hasMethod('BackLinkTracking')) {
				$links = $this->BackLinkTracking();
				if($links) {
					foreach($links as $link) {
						$link->rewriteLink($this->original['URLSegment'] . '/', $this->URLSegment . '/');
						$link->write();
					}
				}
			}
		}
				
		parent::onBeforeWrite();
	}
	
	/**
	 * Generate a URL segment based on the title provided.
	 * @param string $title Page title.
	 * @return string Generated url segment
	 */
	function generateURLSegment($title){
		$t = strtolower($title);
		$t = str_replace('&amp;','-and-',$t);
		$t = str_replace('&','-and-',$t);
		$t = ereg_replace('[^A-Za-z0-9]+','-',$t);
		$t = ereg_replace('-+','-',$t);
		if(!$t) {
			$t = "page-$this->ID";
		}
		return $t;
	}
	
	function makelinksunique() {
		$badURLs = "'" . implode("', '", DB::query("SELECT URLSegment, count(*) FROM SiteTree GROUP BY URLSegment HAVING count(*) > 1")->column()) . "'";
		$pages = DataObject::get("SiteTree", "URLSegment IN ($badURLs)");
		
		foreach($pages as $page) {
			echo "<li>$page->Title: ";
			$urlSegment = $page->URLSegment;
			$page->write();
			if($urlSegment != $page->URLSegment) echo " changed $urlSegment -> $page->URLSegment";
			else echo " $urlSegment is already unique";
			die();
		}		
	}
	
	function makelinksuniquequick() {
		$badURLs = "'" . implode("', '", DB::query("SELECT URLSegment, count(*) FROM SiteTree GROUP BY URLSegment HAVING count(*) > 1")->column()) . "'";
		$pages = DB::query("SELECT *, SiteTree.ID FROM SiteTree LEFT JOIN Page ON Page.ID = SiteTree.ID WHERE  URLSegment IN ($badURLs)");
		
		foreach($pages as $page) {
			echo "<li>$page[Title]: ";
			$urlSegment = $page['URLSegment'];
			$newURLSegment = $urlSegment . '-' . $page['ID'];
			DB::query("UPDATE SiteTree SET URLSegment = '$newURLSegment' WHERE ID = $page[ID]");
			if($urlSegment != $newURLSegment) echo " changed $urlSegment -> $newURLSegment";
			else echo " $urlSegment is already unique";
		}		
		echo "<p>done";
	}
	
	/**
	 * Replace a URL in html content with a new URL.
	 * @param string $old The old URL
	 * @param string $new The new URL
	 */
	function rewriteLink($old, $new) {
		$fields = $this->getCMSFields(null)->dataFields();
		foreach($fields as $field) {
			if(is_a($field, 'HtmlEditorField')) {
				$fieldName = $field->Name();
				$field->setValue($this->$fieldName);
				$field->rewriteLink($old, $new);
				$field->saveInto($this);
			}
		}
	}
	
	//------------------------------------------------------------------------------------//
	
	/**
	 * Holds callback functions to be called when getCMSFields() is called
	 *
	 * @var array
	 */
	static $cms_additions = array();


	/**
	 * Allows modules to extend the cms editing form for all pages in the site
	 *
	 * @param mixed $function the name of your function, either as a string,
	 *                        or in the form array('class','function)
	 */
	static function ExtendCMS($function)
	{
		self::$cms_additions[] = $function;
	}


	/**
	 * Returns a FieldSet with which to create the CMS editing form.
	 * You can override this in your child classes to add extra fields - first
	 * get the parent fields using parent::getCMSFields(), then use addFieldToTab()
	 * on the FieldSet.
	 * @return FieldSet The fields to be displayed in the CMS.
	 */
	function getCMSFields() {
		require_once("forms/Form.php");
		Requirements::javascript("cms/javascript/SitetreeAccess.js");

		// Backlink report
		if($this->hasMethod('BackLinkTracking')) {
			$links = $this->BackLinkTracking();
			if($links->exists()) {
				foreach($links as $link) {
					$backlinks[] = "<li><a class=\"cmsEditlink\" href=\"admin/show/$link->ID\">" . $link->Breadcrumbs(null,true). "</a></li>";
				}
				$backlinks = "<div style=\"clear:left\">The following pages link to this page:<ul>" . implode("",$backlinks) . "</ul></div>";
			}
		}
		if(!isset($backlinks)) {
			$backlinks = "<p>This page hasn't been linked to from any pages.</p>";
		}
		
		// Status / message
		// Create a status message for multiple parents
		if($this->ID && is_numeric($this->ID)) {
			$linkedPages = DataObject::get("VirtualPage", "CopyContentFromID = $this->ID");
		}

		if(isset($linkedPages)) {
			foreach($linkedPages as $linkedPage) {
				$parentPage = $linkedPage->Parent;
				$parentPageTitle = $parentPage->Title;
				
				if($parentPage->ID) {
					$parentPageLinks[] = "<a class=\"cmsEditlink\" href=\"admin/show/$linkedPage->ID\">{$parentPage->Title}</a>";
				} else {
					$parentPageLinks[] = "<a class=\"cmsEditlink\" href=\"admin/show/$linkedPage->ID\">Site Content (Top Level)</a>";
				}
			}
			
			$lastParent = array_pop($parentPageLinks);
			$parentList = "'$lastParent'";
			
			if(count( $parentPageLinks ) > 0) {
				$parentList = "'" . implode("', '", $parentPageLinks) . "' and " . $parentList;
			}
			
			$statusMessage[] = "This content also appears on the virtual pages in the $parentList sections.";
		}
		
		if($this->HasBrokenLink || $this->HasBrokenFile) {
			$statusMessage[] = "This page has broken links.";
		}
		
		$message = "STATUS: $this->Status<br />";
		if(isset($statusMessage)) {
			$message .= "NOTE: " . implode("<br />", $statusMessage);
		}

		// Lay out the fields		
		$fields = new FieldSet(
			new TabSet("Root",
				new TabSet("Content",
					new Tab("Main",
						new TextField("Title", "Page name"),
						/*new UniqueTextField("Title",
								"Title",
								"SiteTree",
								"Another page is using that name. Page names should be unique.",
								"Page Name"
						),*/
						new TextField("MenuTitle", "Navigation label"),
						new HtmlEditorField("Content","Content")
					),
					new Tab("Meta-data",
						new FieldGroup("URL",
							new LabelField("http://www.yoursite.com/"),
							//new TextField("URLSegment",""),
							new UniqueRestrictedTextField("URLSegment",
								"URLSegment",
								"SiteTree",
								"Another page is using that URL. URL must be unique for each page",
								"[^A-Za-z0-9-]+",
								"-",
								"URLs can only be made up of letters, digits and hyphens.",
								""
							),
							new LabelField("/")
						),
						new HeaderField("Search Engine Meta-tags"),
						new TextField("MetaTitle", "Title"),
						new TextareaField("MetaDescription", "Description"),
						new TextareaField("MetaKeywords", "Keywords")
					)
				),
				new Tab("Behaviour",
					new DropdownField("ClassName", "Page type", $this->getClassDropdown()),
					new CheckboxField("ShowInMenus", "Show in menus?"),
					new CheckboxField("ShowInSearch", "Show in search?"),
					/*, new TreeMultiselectField("MultipleParents", "Page appears within", "SiteTree")*/
					new CheckboxField("ProvideComments", "Allow comments on this page?"),
					new LiteralField("", "<p>Use this page as the 'home page' for the following domains: (separate multiple domains with commas)</p>"),
					new TextField("HomepageForDomain", "Domain(s)")
				),
				new TabSet("Reports",
					new Tab("BackLinks",
						new LiteralField("Backlinks", $backlinks)
					)
				),
				new Tab("Access",
					new HeaderField("Who can display this?", 2),
					new OptionsetField("Viewers", "",
														 array("Anyone" => "Anyone",
																	 "LoggedInUsers" => "Logged-in users",
																	 "OnlyTheseUsers" => "Only these people (choose from list)")),
					new DropdownField("ViewersGroup", "Group", Group::map()),
					new HeaderField("Who can edit this?", 2),
					new OptionsetField("Editors", "",
														 array("LoggedInUsers" => "Logged-in users",
																	 "OnlyTheseUsers" => "Only these people (choose from list)")),
					new DropdownField("EditorsGroup", "Group", Group::map())
				)
			),
			new NamedLabelField("Status", $message, "pageStatusMessage", true)
		);
		
		foreach(self::$cms_additions as $extension)
		{
			$fields = call_user_func($extension,$fields);
		}

		return $fields;
	}

	/**
	 * Get the actions available in the CMS for this page - eg Save, Publish.
	 * @return DataObjectSet The available actions for this page.
	 */
	function getCMSActions() {
		$actions = array();
		if($this->isPublished() && $this->canPublish()) {
			$actions[] = FormAction::create('unpublish', 'Unpublish')->describe("Remove this page from the published site");
		}
		if($this->stagesDiffer('Stage','Live')) {
			if($this->isPublished() && $this->canEdit())	{
				$actions[] = FormAction::create('rollback', 'Cancel draft changes')->describe("Delete your draft and revert to the currently published page");
			}
		}

		if($this->canPublish())
			$actions[] = new FormAction('publish', 'Save & Publish');

		return new DataObjectSet($actions);
	}
	
	/**
	 * Check if this page is new - that is, if it has yet to have been written
	 * to the database.
	 * @return boolean True if this page is new.
	 */
	function isNew() {
		/**
		 * This check was a problem for a self-hosted site, and may indicate a bug in the interpreter on their server, or a bug here
		 * Changing the condition from empty( $this->ID ) to !$this->ID && !$this->record['ID'] fixed this.
		 */
		if(empty($this->ID))
			return true;
		
		if(is_numeric($this->ID))
			return false;
		
		return stripos($this->ID, 'new') === 0;
	}
	
	/**
	 * Check if this page has been published.
	 * @return boolean True if this page has been published.
	 */
	function isPublished() {
		if($this->isNew()) return false;
		return DB::query("SELECT ID FROM `SiteTree_Live` WHERE ID = $this->ID")->value() ? true : false;
	}
	
	/**
	 * Look for ghost parents
	 */
	function MultipleParents() {
		$parents = new GhostPage_ComponentSet($this->Parent);
		$parents->setOwner($this);
		$ghostPages = DataObject::get("GhostPage", "LinkedPageID = '$this->ID'");

		if($ghostPages) foreach($ghostPages as $ghostPage) {
			// Ignore root ghost-pages
			if($p = $ghostPage->getParent()) $parents->push($p);
		}
		return $parents;
	}
	
	/**
	 * Get the class dropdown used in the CMS to change the class of a page.
	 * This returns the list of options in the drop as a Map from class name
	 * to text in dropdown.
	 * @return array
	 */
	function getClassDropdown() {
		$classes = ClassInfo::getValidSubClasses('SiteTree');
		array_shift($classes);
		foreach($classes as $class) {
			$instance = singleton($class);
			if(($instance instanceof HiddenClass) && ($class != $this->class)) continue;

			$addAction = $instance->uninherited('add_action', true);
			if(!$addAction) $addAction = "a $class";

			$result[$class] = ($class == $this->class) ? "Currently $addAction" : "Change to $addAction";
		}

		return $result;
	}
	
	/**
	 * Returns an array of the class names of classes that are allowed
	 * to be children of this class.
	 * @return array
	 */
	function allowedChildren() {
		$candidates = $this->stat('allowed_children');
		if($candidates && $candidates != "none" && $candidates != "SiteTree_root") {
			foreach($candidates as $candidate) {
				if(substr($candidate,0,1) == '*') {
					$allowedChildren[] = substr($candidate,1);
				} else {
					$subclasses = ClassInfo::subclassesFor($candidate);
					foreach($subclasses as $subclass) {
						if($subclass != "SiteTree_root") $allowedChildren[] = $subclass;
					}
				}
			}
			return $allowedChildren;
		}
	}
	
	/**
	 * Returns the class name of the default class for children
	 * of this page.
	 * @return string
	 */
	function defaultChild() {
		$default = $this->stat('default_child');
		$allowed = $this->allowedChildren();
		if($allowed) {
			if(!$default || !in_array($default, $allowed))
				$default = reset($allowed);
			return $default;
		}
	}
	
	/**
	 * Returns the class name of the default class for the parent
	 * of this page.
	 * @return string
	 */
	function defaultParent() {
		return $this->stat('default_parent');
	}
	
	/**
	 * Function to clean up the currently loaded page after a reorganise has been called.
	 * It should return a piece of JavaScript to be executed on the client side, to clean
	 * up the results of the reorganise.
	 */
	function cmsCleanup_parentChanged() {
	}
	

	/** 
	 * Get the title for use in menus for this page. If the MenuTitle
	 * field is set it returns that, else it returns the Title field.
	 * @return string
	 */
	function getMenuTitle(){
		if($value = $this->getField("MenuTitle")) {
			return $value;
		} else {
			return $this->getField("Title");
		}
	}
	
	/**
	 * Set the menu title for this page.
	 * @param string $value
	 */
	function setMenuTitle($value) {
		if($value == $this->getField("Title")) {
			$this->setField("MenuTitle", null);
		} else {
			$this->setField("MenuTitle", $value);
		}
	}
		
	/**
	 * TitleWithStatus will return the title in an <ins>, <del> or <span class=\"modified\"> tag
	 * depending on its publication status.
	 * @return string
	 */
	function TreeTitle() {
		// If somthing
		if(!$this->CheckedPublicationDifferences && $this->ID) {
			$stageVersion = DB::query("SELECT Version FROM SiteTree WHERE ID = $this->ID")->value();
			$liveVersion = DB::query("SELECT Version FROM SiteTree_Live WHERE ID = $this->ID")->value();
			
			if($stageVersion && !$liveVersion) $this->AddedToStage = true;
			else if(!$stageVersion && $liveVersion) $this->DeletedFromStage = true;
			else if($stageVersion != $liveVersion) $this->ModifiedOnStage = true;
		}
			
		$tag = 
			($this->DeletedFromStage ? "del title=\"Removed from stage site\"" : 
			($this->AddedToStage ? "ins title=\"Added to stage site\"" : 
			($this->ModifiedOnStage ? "span title=\"Modified on stage site\" class=\"modified\"" : "")));
		
		if($tag) {
			return "<$tag>" . $this->Title . "</" . strtok($tag,' ') . ">";
		}	else {
			return $this->Title;
		}
	}
	
	/**
	 * Return the CSS classes to apply to this node in the CMS tree
	 * @param Controller $controller The controller object that the tree appears on
	 * @return string
	 */
	function CMSTreeClasses($controller) {
		$classes = $this->class;
		if($this->HasBrokenFile || $this->HasBrokenLink) $classes .= " BrokenLink";
		if(!$this->canAddChildren()) $classes .= " nochildren";
		if(!$this->canDelete()) $classes .= " nodelete";
		if($controller->isCurrentPage($this)) $classes .= " current";
		
		$classes .= $this->markingClasses();
		
		return $classes;
	}
	
	/**
	 * Indicates what kind of children this page type can have.
	 * This can be an array of allowed child classes, or the string "none" - indicating that
	 * this page type can't have children.
	 * If a classname is prefixed by "*", such as "*Page", then only that class is allowed - no
	 * subclasses.  Otherwise, the class and all its subclasses are allowed.
	 * @var array
	 */
	static $allowed_children = array("SiteTree");
	
	/**
	 * The default child class for this page.
	 * @var string
	 */
	static $default_child = "Page";
	
	/**
	 * The default parent class for this page.
	 * @var string
	 */
	static $default_parent = null;

	/**
	 * Controls whether a page can be in the root of the site tree.
	 * @var bool
	 */
	static $can_be_root = true;
	
	/**
	 * List of permission codes a user can have to allow a user to create a page
	 * of this type.
	 * @var array
	 */
	static $need_permission = null;
	
	/**
	 * If you extend a class, and don't want to be able to select the old class
	 * in the cms, set this to the old class name. Eg, if you extended Product to
	 * make ImprovedProduct, then you would set $hide_ancestor to Product.
	 * @var string
	 */
	static $hide_ancestor = null;
	
	static $db = array(
		"URLSegment" => "Varchar(255)",
		"Title" => "Varchar(255)",
		"MenuTitle" => "Varchar(100)",
		"Content" => "HTMLText",
		"MetaTitle" => "Varchar(255)",
		"MetaDescription" => "Varchar(255)",
		"MetaKeywords" => "Varchar(255)",
		"ShowInMenus" => "Boolean",
		"ShowInSearch" => "Boolean",
		"HomepageForDomain" => "Varchar(100)",
		"ProvideComments" => "Boolean",
		"Sort" => "Int",
		"LegacyURL" => "Varchar(255)",
		"HasBrokenFile" => "Boolean",
		"HasBrokenLink" => "Boolean",
		"Status" => "Varchar",
		"ReportClass" => "Varchar",
		"Viewers" => "Enum('Anyone, LoggedInUsers, OnlyTheseUsers', 'Anyone')", 
 		"Editors" => "Enum('LoggedInUsers, OnlyTheseUsers', 'LoggedInUsers')", 
 		"ViewersGroup" => "Int", 
 		"EditorsGroup" => "Int" 
	);
  
  static $indexes = array(
    "SearchFields" => "fulltext (Title, MenuTitle, Content, MetaTitle, MetaDescription, MetaKeywords)",
    "TitleSearchFields" => "fulltext (Title)"
  );
  
  	static $has_many = array(
  		"Comments" => "PageComment"
  	);
  
	static $many_many = array(
		"LinkTracking" => "SiteTree",
		"ImageTracking" => "File"
	);
	
	static $belongs_many_many = array(
		"BackLinkTracking" => "SiteTree"
	);
	
	static $many_many_extraFields = array(
		"LinkTracking" => array("FieldName" => "Varchar"),
		"ImageTracking" => array("FieldName" => "Varchar")
	);

	static $casting = array(
		"Breadcrumbs" => "HTMLText",
		"LastEdited" => "Datetime",
		"Created" => "Datetime",
	);
	
	static $defaults = array(
		"ShowInMenus" => 1,
		"ShowInSearch" => 1,
		"Status" => "New page",
		"CanCreateChildren" => array(10),
		"Viewers" => "Anyone", 
 		"Editors" => "LoggedInUsers" 
	);

	static $has_one = array(
		"Parent" => "SiteTree"
	);
	
	static $versioning = array(
		"Stage",  "Live"
	);
	
	static $default_sort = "Sort";
	
	/**
	 * The text shown in the create page dropdown. If
	 * this is not set, default to "Create a ClassName".
	 * @var string
	 */
	static $add_action = null;
	
	/**
	 * If this is false, the class cannot be created in the CMS.
	 * @var boolean
	*/
	static $can_create = true;
	
	/**
	 * Icon to use in the CMS
	 * This should be the base filename.  The suffixes -file.gif, -openfolder.gif and -closedfolder.gif will
	 * be appended to the base name that you provide there.
	 * If you prefer, you can pass an array: array("jsparty/tree/images/page", $option).  $option can be either
	 * "file" or "folder" to force the icon to always be a file or folder, regardless of whether the page has 
	 * children or not
	 * @var string|array
	 */
	static $icon = array("jsparty/tree/images/page", "file");

	static $extensions = array(
		"Hierarchy",
		"Versioned('Stage', 'Live')",
	);
}
?>