<?php

class Marshaller {

    const OBJ_TYPE = '__objectType';

    private static function isWrappedObject($obj) {
        return isset($obj[self::OBJ_TYPE]);
    }

    public static function marshall($obj) {
        switch (gettype($obj)) {
            case 'array':
                return array_map(array('Marshaller','marshall'), $obj);
            case 'object':
                return static::wrapObject($obj);
            default:
                return $obj;
        }
    }

    private static function wrapObject($obj) {
        $objectType = get_class($obj);
        if ($objectType == 'DateTime') {
            return array(self::OBJ_TYPE => 'DateTime', 'timestamp' => $obj->getTimestamp());
        } else {
            $newObj = static::marshall((array) $obj);
            $newObj[self::OBJ_TYPE] = get_class($obj);
            return $newObj;
        }
    }

    public static function unmarshall($obj) {
        switch (gettype($obj)) {
            case 'object':
                $obj = (array) $obj;
            case 'array':
                if (static::isWrappedObject($obj)) {
                    return static::unwrapObject($obj);
                } else {
                    return array_map(array('Marshaller','unmarshall'), $obj);
                }
            default:
                return $obj;
        }
    }

    private static function unwrapObject($obj) {
        $objectType = $obj[self::OBJ_TYPE];
        unset($obj[self::OBJ_TYPE]);
        if ($objectType == 'DateTime') {
            $date = new DateTime();
            $date->setTimestamp($obj['timestamp']);
            return $date;
        } else if (is_subclass_of($objectType, 'ResearchToolObjectInterface')) {
            return $objectType::create((object)static::unmarshall($obj));
        } else {
            return $obj;
        }
    }

}

?>