<?php

/**
 * Widgets let CMS authors drag and drop small pieces of functionality into  
 * defined areas of their websites.
 * 
 * You can use forms in widgets by implementing a {@link WidgetController}.
 * 
 * See {@link Widget_Controller} for more information.
 * 
 * @package widgets
 */
class Widget extends DataObject {

	/**
	 * @var array
	 */
	private static $db = array(
		"Sort" => "Int",
		"Enabled" => "Boolean"
	);

	/**
	 * @var array
	 */
	private static $defaults = array(
		'Enabled' => true
	);

	/**
	 * @var array
	 */
	private static $has_one = array(
		"Parent" => "WidgetArea",
	);

	/**
	 * @var array
	 */
	private static $has_many = array();

	/**
	 * @var array
	 */
	private static $many_many = array();

	/**
	 * @var array
	 */
	private static $belongs_many_many = array();

	/**
	 * @var string
	 */
	private static $default_sort = "\"Sort\"";

	/**
	 * @var string
	 */
	private static $title = "Widget Title";

	/**
	 * @var string
	 */
	private static $cmsTitle = "Name of this widget";

	/**
	 * @var string
	 */
	private static $description = "Description of what this widget does.";

	/**
	 * @var WidgetController
	 */
	protected $controller;

	/**
	 *
	 * @return FieldList
	 */
	public function getCMSFields() {
		$fields = new FieldList();
		$this->extend('updateCMSFields', $fields);

		return $fields;
	}
	
	/**
	 * Note: Overloaded in {@link WidgetController}.
	 * 
	 * @return string HTML
	 */
	public function WidgetHolder() {
		return $this->renderWith("WidgetHolder");
	}
	
	/**
	 * Renders the widget content in a custom template with the same name as the 
	 * current class. This should be the main point of output customization.
	 * 
	 * Invoked from within WidgetHolder.ss, which contains the "framing" around 
	 * the custom content, like a title.
	 * 
	 * Note: Overloaded in {@link WidgetController}.
	 * 
	 * @return string HTML
	 */
	public function Content() {
		return $this->renderWith(array_reverse(ClassInfo::ancestry($this->class)));
	}

	/**
	 * @return string
	 */
	public function Title() {
		return _t($this->class.'.TITLE', $this->config()->title);
	}

	/**
	 * @return string
	 */
	public function CMSTitle() {
		return _t($this->class.'.CMSTITLE', $this->config()->cmsTitle);
	}

	/**
	 * @return string
	 */
	public function Description() {
		return _t($this->class.'.DESCRIPTION', $this->config()->description);
	}

	/**
	 * @return string - HTML
	 */
	public function DescriptionSegment() {
		return $this->renderWith('WidgetDescription'); 
	}
	
	/**
	 * @see WidgetController::editablesegment()
	 *
	 * @return string - HTML
	 */
	public function EditableSegment() {
		return $this->renderWith('WidgetEditor'); 
	}

	/**
	 * @return FieldList
	 */
	public function CMSEditor() {
		$fields = $this->getCMSFields();
		$outputFields = new FieldList();

		foreach($fields as $field) {
			$name = $field->getName();
			$value = $this->getField($name);
			if ($value) {
				$field->setValue($value);
			}
			$name = preg_replace("/([A-Za-z0-9\-_]+)/", "Widget[" . $this->ID . "][\\1]", $name);
			$field->setName($name);
			$outputFields->push($field);
		}

		return $outputFields;
	}

	/**
	 * @return string
	 */
	public function ClassName() {
		return $this->class;
	}

	/**
	 * @return string
	 */
	public function Name() {
		return "Widget[".$this->ID."]";
	}

	/**
	 * @throws Exception
	 *
	 * @return WidgetController
	 */
	public function getController() {
		if($this->controller) {
			return $this->controller;
		}

		foreach(array_reverse(ClassInfo::ancestry($this->class)) as $widgetClass) {
			$controllerClass = "{$widgetClass}_Controller";
			
			if(class_exists($controllerClass)) {
				break;
			}

			$controllerClass = "{$widgetClass}Controller";
		
			if(class_exists($controllerClass)) {
				break;
			}
		}

		if(!class_exists($controllerClass)) {
			throw new Exception("Could not find controller class for $this->classname");
		}

		$this->controller = Injector::inst()->create($controllerClass, $this);

		return $this->controller;
	}
	
	/**
	 * @param array $data
	 */
	public function populateFromPostData($data) {
		$fields = $this->getCMSFields();
		foreach($data as $name => $value) {
			if($name != "Type") {
				if ($field = $fields->dataFieldByName($name)) {
					$field->setValue($value);
					$field->saveInto($this);
				}
				else {
					$this->setField($name, $value);
				}
			}
		}
		
		$this->write();
		
		// The field must be written to ensure a unique ID.
		$this->Name = $this->class.$this->ID;
		$this->write();
	}	
}