<?php

if(!function_exists("CS_REST_SERIALISATION_get_available")) {
    function CS_REST_SERIALISATION_get_available($log) { 
        $log->log_message('Getting serialiser', __FUNCTION__, CS_REST_LOG_VERBOSE);
        if(function_exists('json_decode') && function_exists('json_encode')) {
            return new CS_REST_NativeJsonSerialiser($log);
        } else {
            return new CS_REST_ServicesJsonSerialiser($log);
        }    
    }
}

if (!class_exists('CS_REST_BaseSerialiser')) {
    class CS_REST_BaseSerialiser {

        var $_log;
        
        function __construct($log) {
            $this->_log = $log;
        }
        
        /**
         * Recursively ensures that all data values are utf-8 encoded. 
         * @param array $data All values of this array are checked for utf-8 encoding. 
         */
        function check_encoding($data) {

            foreach($data as $k => $v) {
                // If the element is a sub-array then recusively encode the array
                if(is_array($v)) {
                    $data[$k] = $this->check_encoding($v);
                // Otherwise if the element is a string then we need to check the encoding
                } else if(is_string($v)) {
                    if((function_exists('mb_detect_encoding') && mb_detect_encoding($v) !== 'UTF-8') || 
                       (function_exists('mb_check_encoding') && !mb_check_encoding($v, 'UTF-8'))) {
                        // The string is using some other encoding, make sure we utf-8 encode
                        $v = utf8_encode($v);       
                    }
                    
                    $data[$k] = $v;
                }
            }
                  
            return $data;
        }    
    }
}

if (!class_exists('CS_REST_DoNothingSerialiser')) {
    class CS_REST_DoNothingSerialiser extends CS_REST_BaseSerialiser {
    function __construct() {}
        function get_type() { return 'do_nothing'; }
        function serialise($data) { return $data; }
        function deserialise($text) {
            $data = json_decode($text);
            return is_null($data) ? $text : $data;
        }
        function check_encoding($data) { return $data; }
    }
}

if (!class_exists('CS_REST_NativeJsonSerialiser')) {
    class CS_REST_NativeJsonSerialiser extends CS_REST_BaseSerialiser {

        function get_format() {
            return 'json';
        }
        
        function get_type() {
            return 'native';
        }

        function serialise($data) {
        	if(is_null($data) || $data == '') return '';
            return json_encode($this->check_encoding($data));
        }

        function deserialise($text) {
            $data = json_decode($text);

            return $this->strip_surrounding_quotes(is_null($data) ? $text : $data);
        }

        /** 
         * We've had sporadic reports of people getting ID's from create routes with the surrounding quotes present. 
         * There is no case where these should be present. Just get rid of it. 
         */
        function strip_surrounding_quotes($data) {
            if(is_string($data)) {
                return trim($data, '"');
            }

            return $data;
        }
    }
}

if (!class_exists('CS_REST_ServicesJsonSerialiser')) {
    class CS_REST_ServicesJsonSerialiser extends CS_REST_BaseSerialiser {
        
        var $_serialiser;
        
        function __construct($log) {
            parent::__construct($log);
            if (!class_exists('Services_JSON', false)) {
                require_once dirname(__FILE__).'/services_json.php';
            }

            $this->_serialiser = new Services_JSON();
        }

        function get_content_type() {
            return 'application/json';
        }

        function get_format() {
            return 'json';
        }
        
        function get_type() {
            return 'services_json';
        }
        
        function serialise($data) {
        	if(is_null($data) || $data == '') return '';
            return $this->_serialiser->encode($this->check_encoding($data));
        }
        
        function deserialise($text) {
            $data = $this->_serialiser->decode($text);
            
            return is_null($data) ? $text : $data;
        }
    }
}