OpenGraph.php

<?php
namespace dragonjet\opengraph;
use Yii;
use yii\web\View;

class OpenGraph {
	public $title;
	public $site_name;
	public $url;
	public $description;
	public $type;
	public $locale;
	public $image;
	
	public function __construct(){
		// Load default values
		$this->title = Yii::$app->name;
		$this->site_name = Yii::$app->name;
		$this->url = Yii::$app->request->absoluteUrl;
		$this->description = null;
		$this->type = 'article';
		$this->locale = str_replace('-','_',Yii::$app->language);
		$this->image = null;
		
		// Twitter Card
		$this->twitter = new TwitterCard;
		
		// Listed to Begin Page View event to start adding meta
		Yii::$app->view->on(View::EVENT_BEGIN_PAGE, function(){
			// Register required and easily determined open graph data
			Yii::$app->controller->view->registerMetaTag(['property'=>'og:title', 'content'=>$this->title], 'og:title');
			Yii::$app->controller->view->registerMetaTag(['property'=>'og:site_name', 'content'=>$this->site_name], 'og:site_name');
			Yii::$app->controller->view->registerMetaTag(['property'=>'og:url', 'content'=>$this->url], 'og:url');
			Yii::$app->controller->view->registerMetaTag(['property'=>'og:type', 'content'=>$this->type], 'og:type');
			
			// Locale issafe to be specifued since it has default value on Yii applications
			Yii::$app->controller->view->registerMetaTag(['property'=>'og:locale', 'content'=>$this->locale], 'og:locale');
			
			// Only add a description meta if specified
			if($this->description!==null){
				Yii::$app->controller->view->registerMetaTag(['property'=>'og:description', 'content'=>$this->description], 'og:description');
			}
			
			// Only add an image meta if specified
			if($this->image!==null){
				Yii::$app->controller->view->registerMetaTag(['property'=>'og:image', 'content'=>$this->image], 'og:image');
			}
			
			$this->twitter->registerTags();
		});
	}
	
	
	public function set($metas=[]){
		// Massive assignment by array
		foreach($metas as $property=>$content){
			if($property=='twitter'){
				$this->twitter->set($content);
			}else if(property_exists($this, $property)){
				$this->$property = $content;
			}
		}
	}
	
}