<?php

/**

 * @author    ThemePunch <info@themepunch.com>

 * @link      http://www.themepunch.com/

 * @copyright 2016 ThemePunch

 */



if( !defined( 'ABSPATH') ) exit();



class RevSliderPageTemplate {



	/**

	 * A reference to an instance of this class.

	 */

	private static $instance;



	/**

	 * The array of templates that this plugin tracks.

	 */

	protected $templates;





	/**

	 * Returns an instance of this class. 

	 */

	public static function get_instance() {



		if( null == self::$instance ) {

			self::$instance = new RevSliderPageTemplate();

		} 



		return self::$instance;



	} 



	/**

	 * Initializes the plugin by setting filters and administration functions.

	 */

	private function __construct() {



		$this->templates = array();





		// Add a filter to the attributes metabox to inject template into the cache.

		add_filter(

			'page_attributes_dropdown_pages_args',

			array( $this, 'register_project_templates' ) 

		);





		// Add a filter to the save post to inject out template into the page cache

		add_filter(

			'wp_insert_post_data', 

			array( $this, 'register_project_templates' ) 

		);





		// Add a filter to the template include to determine if the page has our 

		// template assigned and return it's path

		add_filter(

			'template_include', 

			array( $this, 'view_project_template') 

		);





		// Add your templates to this array.

		$this->templates = array(

			'../public/views/revslider-page-template.php' => 'Slider Revolution Blank Template',

		);

		

		// Fix for WP 4.7

		add_filter( 'theme_page_templates', array($this, 'register_project_templates_new' ) );

		

	} 





	// Adds our template to the new post templates setting (WP >= 4.7)

	public function register_project_templates_new( $post_templates ) {

	    

	    $post_templates = array_merge( $post_templates, $this->templates );

	 

	    return $post_templates;

	}





	/**

	 * Adds our template to the pages cache in order to trick WordPress

	 * into thinking the template file exists where it doens't really exist.

	 *

	 */



	public function register_project_templates( $atts ) {



		// Create the key used for the themes cache

		$cache_key = 'page_templates-' . md5( get_theme_root() . '/' . get_stylesheet() );



		// Retrieve the cache list. 

		// If it doesn't exist, or it's empty prepare an array

		$templates = wp_get_theme()->get_page_templates();



		if ( empty( $templates ) ) {

			$templates = array();

		} 



		// New cache, therefore remove the old one

		wp_cache_delete( $cache_key , 'themes');



		// Now add our template to the list of templates by merging our templates

		// with the existing templates array from the cache.

		$templates = array_merge( $templates, $this->templates );



		// Add the modified cache to allow WordPress to pick it up for listing

		// available templates

		wp_cache_add( $cache_key, $templates, 'themes', 1800 );



		return $atts;



	} 



	/**

	 * Checks if the template is assigned to the page

	 */

	public function view_project_template( $template ) {



		global $post;

		

		if(!isset($post->ID)) return $template;

			

		if (!isset($this->templates[get_post_meta( 

			$post->ID, '_wp_page_template', true 

		)] ) ) {

		

			return $template;

			

		} 



		$file = plugin_dir_path(__FILE__). get_post_meta( 

			$post->ID, '_wp_page_template', true 

		);

		

		// Just to be safe, we check if the file exist first

		if( file_exists( $file ) ) {

			return $file;

		} 

		else { echo $file; }



		return $template;



	}

}

?>