1: <?php
 2: 
 3: namespace Xu\Foundation;
 4: 
 5: abstract class Jsonable {
 6: 
 7:     /**
 8:      * Convert the object into something JSON serializable.
 9:      *
10:      * @return array
11:      */
12:     public function json_serialize() {
13:         $items = $this->to_array();
14: 
15:         foreach ( $items as $key => $value ) {
16:             if ( $value instanceof Jsonable ) {
17:                 $items[$key] = $value->json_serialize();
18:             }
19:         }
20: 
21:         return $items;
22:     }
23: 
24:     /**
25:      * Convert the class to array.
26:      *
27:      * @return array
28:      */
29:     abstract public function to_array();
30: 
31:     /**
32:      * Convert the class instance to JSON.
33:      *
34:      * @param  int $options
35:      *
36:      * @return string
37:      */
38:     public function to_json( $options = 0 ) {
39:         return json_encode( $this->json_serialize(), $options );
40:     }
41: }
42: