<?php

/**
 * This class gets decorated on {@link SiteTree} subclasses (that do not already have it applied)
 * {@see BedrockPage}. It handles the distribution of extra static vars and the construction of 
 * a CMS interface for the page type.
 *
 * @package Bedrock
 */
class BedrockSiteTree extends BedrockExtension 
{


	/**
	 * Provide extra static vars based on the class configuration. This adds databse fields, related
	 * objects, and class properties such as $can_create and $allowed_children
	 *
	 * @param string $class The class to which the vars will apply
	 * @return array
	 */
	public function extraStatics($class) {
		$statics = self::load_statics($class);
		if($settings = Bedrock::get_page_type($class)) {
			if($v = $settings->getAllowedChildren()) {
				if($v instanceof BedrockSetting)
					$v = $v->toArray();
				$statics['allowed_children'] = $v;
			}
			$statics['default_child'] = $settings->getDefaultChild();
			$statics['default_parent'] = $settings->getDefaultParent();
			$statics['can_be_root'] = $settings->getCanBeRoot();
			$statics['need_permission'] = $settings->getNeedPermission();
			$statics['hide_ancestor'] = $settings->getHideAncestor();
			$statics['default_sort'] = $settings->getDefaultSort();
			$statics['can_create'] = $settings->getCanCreate();
			$statics['icon'] = $settings->getIcon();
			if($v = $settings->getEnforceParentChild()) {
				if(class_exists($v)) {
					Object::set_static($v, 'can_be_root', false);
					$statics['default_child'] = $v;
					$statics['allowed_children'] = array($v);
				}
			}
		}
		$r_statics = $statics;
		$r_statics['belongs_many_many'] = Object::get_static($class, 'belongs_many_many');
		$r_statics = print_r($r_statics, true);

		Bedrock::message("Statics for class $class: $r_statics","");		
		return $statics;			
	}	
	
	/**
	 * Based on the class configuration, build a CMS interface for this page, respecting
	 * all of the database fields and related objects.
	 *
	 * @param FieldSet $fieldset A reference to a fieldset that has already been create
	 *							 by this class
	 */
	public function updateCMSFields(&$fieldset) {
		if(!$this->getClassSettings())
			return;
			
		$class = $this->owner->class;

		// Is this a subclass of a page already decorated? If so, get its fields.
		$parent = get_parent_class($this->owner->class);
		while(!in_array($parent, array('DataObject','SiteTree'))) {
			if(Object::has_extension($parent, "BedrockSiteTree") || Object::has_extension($parent, "BedrockPage")) {
				$SNG = singleton($parent);
				$SNG->defineMethods();
				// Force the ID so relations don't get messed up.
				$SNG->ID = $this->owner->ID;
				$SNG->updateCMSFields(&$fieldset);
			}
			$parent = get_parent_class($parent);
		}

		if($fields = $this->getClassSettings()->getFields()) {
			foreach($fields as $field) {
				$field->setControllerClass($class);
				$form_field = $field->getFormField();
				if($t = $field->getTab()) {
					$fieldset->addFieldToTab($field->getTab(), $form_field, $field->getBefore());
				}
				else {
					$fieldset->push($form_field);
				}
			}
		}
		if($components = $this->getClassSettings()->getComponents()) {
			foreach($components as $component) {
				if($type = $component->getType()) {
					$component->setControllerClass($class);
					$interface = $component->buildInterface($this->owner);
					if($interface) {
						$fieldset->addFieldToTab($component->getTab(), $interface);
					}
				}
			}
		}
		parent::updateCMSFields($fieldset);		
	}
	
	/**
	 * Override the canCreate() method to check the AllowedInstances property.
	 * Note: this method always returns TRUE for admin users.
	 *
	 * @return boolean
	 */
	public function canCreate() {
		if($settings = $this->getClassSettings()) {
			if($instances = $settings->getAllowedInstances()) {
				if($set = DataObject::get($this->owner->class))
					return $set->Count() < $instances;
			}
		}
	}
	
	/**
	 * A useful method for getting a single record from the database.
	 * Ex. <% control Singleton(HomePage) %>
	 *
	 * @param string $class The class to fetch from the database
	 * @return DataObject
	 */
	public function Singleton($class) {
		if(class_exists($class)) {
     		return DataObject::get_one($class);
     	}
     	return false;
	}
	
	/**
	 * Using {@link Singleton()}, get a link to a single record in the database
	 *
	 * @param string $class The class of page to link to
	 * @return string
	 */
	public function SingleLink($class) {
	   if($o = $this->Singleton($class))
	     return $o->Link();
	   return false;
	}
	
	/**
	 * A useful method for getting an all-inclusive set of records at the template level.
	 * Ex. <% control Set(Objects) %>
	 *
	 * @param string $class The type of object to fetch
	 * @return DataObjectSet
	 */
	public function Set($class)	{
	   return DataObject::get($class);
	}
}