<?php
namespace Concrete\Core\View;
use Concrete\Core\Http\ResponseAssetGroup;
use Request;
use URL;
use Loader;

abstract class AbstractView {

	protected static $requestInstance;
	protected static $requestInstances = array();
	protected $scopeItems = array();

	public function addScopeItems($items) {
		foreach($items as $key => $value) {
			$this->scopeItems[$key] = $value;
		}
	}

	public static function getRequestInstance() {
		if (null === self::$requestInstance) {
			View::setRequestInstance(new View());
		}
		return self::$requestInstance;
	}

	public function __construct($mixed = false) {
		$this->constructView($mixed);
	}

	protected static function setRequestInstance(View $v) {
		View::$requestInstances[] = $v;
		self::$requestInstance = $v;
	}

	protected static function revertRequestInstance() {
		array_pop(View::$requestInstances);
		self::$requestInstance = View::$requestInstances[count(View::$requestInstances)];
	}

	public $controller;

	protected $template;
	protected $outputAssets = array();

	abstract public function start($state);
	public function startRender() {
		if (is_object($this->controller)) {
			$this->controller->on_before_render();
		}
	}
	abstract protected function constructView($mixed);
	abstract public function setupRender();
	abstract public function finishRender($contents);
	abstract public function action($action);


	public function addHeaderAsset($asset) {
		$r = ResponseAssetGroup::get();
		$r->addHeaderAsset($asset);
	}

	public function addFooterAsset($asset) {
		$r = ResponseAssetGroup::get();
		$r->addFooterAsset($asset);
	}

	public function addOutputAsset($asset) {
		$r = ResponseAssetGroup::get();
		$r->addOutputAsset($asset);
	}

	public function requireAsset($assetType, $assetHandle = false) {
		$r = ResponseAssetGroup::get();
		$r->requireAsset($assetType, $assetHandle);
	}

	public function setController($controller) {
		$this->controller = $controller;
	}

	public function setViewTemplate($template) {
		$this->template = $template;
	}

	/**
	 * Returns the value of the item in the POST array.
	 * @access public
	 * @param $key
	 * @return void
	*/
	public function post($key, $defaultValue = null) {
		$r = Request::getInstance();
		return $r->post($key, $defaultValue);
	}

	abstract protected function onBeforeGetContents();

	protected function postProcessViewContents($contents) {return $contents;}
	protected function onAfterGetContents() {}

	public function getScopeItems() {
		if (is_object($this->controller)) {
			$sets = $this->controller->getSets();
			$helpers = $this->controller->getHelperObjects();
			$return = array_merge($this->scopeItems, $sets, $helpers);
		} else {
			$return = $this->scopeItems;
		}
		$return['view'] = $this;
		$return['controller'] = $this->controller;
		return $return;
	}

	public function render($state = false) {
		if ($this instanceof View) {
			$this->setRequestInstance($this);
		}
		$this->start($state);
		$this->setupRender();
		$this->startRender();
		$scopeItems = $this->getScopeItems();
		$contents = $this->renderViewContents($scopeItems);
		$contents = $this->postProcessViewContents($contents);
		$response = $this->finishRender($contents);
		if ($this instanceof View) {
			$this->revertRequestInstance();
		}
		return $response;
	}

	public function renderViewContents($scopeItems) {
		if (file_exists($this->template)) {
			extract($scopeItems);
			ob_start();
			$this->onBeforeGetContents();
			include($this->template);
			$this->onAfterGetContents();
			$contents = ob_get_contents();
			ob_end_clean();
			return $contents;
		}
	}

	/**
	 * url is a utility function that is used inside a view to setup urls w/tasks and parameters
	 * @deprecated
	 * @param string $action
	 * @param string $task
	 * @return string $url
	*/
	public function url($action, $task = null) {
		$args = func_get_args();
		return (string) call_user_func_array(array('URL', 'to'), $args);
	}

	// Legacy Items. Deprecated

	public function setThemeByPath($path, $theme = NULL, $wrapper = FILENAME_THEMES_VIEW) {
		$l = Router::get();
		$l->setThemeByRoute($path, $theme, $wrapper);
	}


	public function renderError($title, $error, $errorObj = null) {
		Loader::helper('concrete/ui')->renderError($title, $error);
	}

	/**
	 * @access private
	 */
	public function addHeaderItem($item) {
		$this->addHeaderAsset($item);
	}

	/**
	 * @access private
	 */
	public function addFooterItem($item) {
		$this->addFooterAsset($item);
	}

    /**
     * @return View
     */
    public static function getInstance() {
		return View::getRequestInstance();
	}


}