<?php

if( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly

if( ! class_exists('ACF_Ajax') ) :

class ACF_Ajax {
	
	/** @var string The AJAX action name. */
	var $action = '';
	
	/** @var array The $_REQUEST data. */
	var $request;
	
	/** @var bool Prevents access for non-logged in users. */
	var $public = false;
	
	/**
	 * __construct
	 *
	 * Sets up the class functionality.
	 *
	 * @date	31/7/18
	 * @since	5.7.2
	 *
	 * @param	void
	 * @return	void
	 */
	function __construct() {
		$this->initialize();
		$this->add_actions();
	}
	
	/**
	 * has
	 *
	 * Returns true if the request has data for the given key.
	 *
	 * @date	31/7/18
	 * @since	5.7.2
	 *
	 * @param	string $key The data key.
	 * @return	boolean
	 */
	function has( $key = '' ) {
		return isset($this->request[$key]);
	}
	
	/**
	 * get
	 *
	 * Returns request data for the given key.
	 *
	 * @date	31/7/18
	 * @since	5.7.2
	 *
	 * @param	string $key The data key.
	 * @return	mixed
	 */
	function get( $key = '' ) {
		return isset($this->request[$key]) ? $this->request[$key] : null;
	}
	
	/**
	 * Sets request data for the given key.
	 *
	 * @date	31/7/18
	 * @since	5.7.2
	 *
	 * @param	string $key The data key.
	 * @param	mixed $value The data value.
	 * @return	ACF_Ajax
	 */
	function set( $key = '', $value = null ) {
		$this->request[$key] = $value;
		return $this;
	}
	
	/**
	 * initialize
	 *
	 * Allows easy access to modifying properties without changing constructor.
	 *
	 * @date	31/7/18
	 * @since	5.7.2
	 *
	 * @param	void
	 * @return	void
	 */
	function initialize() {
		/* do nothing */
	}
	
	/**
	 * add_actions
	 *
	 * Adds the ajax actions for this response.
	 *
	 * @date	31/7/18
	 * @since	5.7.2
	 *
	 * @param	void
	 * @return	void
	 */
	function add_actions() {
		
		// add action for logged-in users
		add_action( "wp_ajax_{$this->action}", array($this, 'request') );
		
		// add action for non logged-in users
		if( $this->public ) {
			add_action( "wp_ajax_nopriv_{$this->action}", array($this, 'request') );
		}
	}
	
	/**
	 * request
	 *
	 * Callback for ajax action. Sets up properties and calls the get_response() function.
	 *
	 * @date	1/8/18
	 * @since	5.7.2
	 *
	 * @param	void
	 * @return	void
	 */
	function request() {
		
		// Store data for has() and get() functions.
		$this->request = wp_unslash($_REQUEST);
		
		// Verify request and handle error.
		$error = $this->verify_request( $this->request );
		if( is_wp_error( $error ) ) {
			$this->send( $error );
		}
		
		// Send response.
		$this->send( $this->get_response( $this->request ) );
	}
	
	/**
	 * Verifies the request.
	 *
	 * @date	9/3/20
	 * @since	5.8.8
	 *
	 * @param	array $request The request args.
	 * @return	(bool|WP_Error) True on success, WP_Error on fail.
	 */
	function verify_request( $request ) {
		
		// Verify nonce.
		if( !acf_verify_ajax() ) {
			return new WP_Error( 'acf_invalid_nonce', __( 'Invalid nonce.', 'acf' ), array( 'status' => 404 ) );
		}
		return true;
	}
	
	/**
	 * get_response
	 *
	 * Returns the response data to sent back.
	 *
	 * @date	31/7/18
	 * @since	5.7.2
	 *
	 * @param	array $request The request args.
	 * @return	mixed The response data or WP_Error.
	 */
	function get_response( $request ) {
		return true;
	}
	
	/**
	 * send
	 *
	 * Sends back JSON based on the $response as either success or failure.
	 *
	 * @date	31/7/18
	 * @since	5.7.2
	 *
	 * @param	mixed $response The response to send back.
	 * @return	void
	 */
	function send( $response ) {
		
		// Return error.
		if( is_wp_error($response) ) {
			$this->send_error( $response );
		
		// Return success.
		} else {
			wp_send_json( $response );
		}
	}
	
	/**
	 * Sends a JSON response for the given WP_Error object.
	 *
	 * @date	8/3/20
	 * @since	5.8.8
	 *
	 * @param	WP_Error error The error object.
	 * @return	void
	 */
	function send_error( $error ) {
		
		// Get error status
		$error_data = $error->get_error_data();
		if( is_array($error_data) && isset($error_data['status']) ) {
			$status_code = $error_data['status'];
		} else {
			$status_code = 500;
		}
		
		wp_send_json(array(
			'code'		=> $error->get_error_code(),
			'message'	=> $error->get_error_message(),
			'data'		=> $error->get_error_data()
		), $status_code);
	}
}

endif; // class_exists check

?>