Magento 2 - Generate model interface

<?php
$json = '{
    "provider": "OMNIVA",
    "type": "POST_OFFICE",
    "name": "Abja-Paluoja postkontor",
    "city": "Abja vald",
    "country": "ESTONIA",
    "availability": "E,T,K,R 8:30-13:00 ja 13:30-16:00;N 8:30-13:00 ja 13:30-18:00;L,P suletud",
    "destination_id": 69400,
    "street_address": "P\u00e4rnu maantee 8",
    "postal_code": "69400",
    "coordinate_x": "58.1264356146443",
    "coordinate_y": "25.3548298784361",
    "temp_service_hours": null,
    "temp_service_hours_until": null,
    "temp_service_hours_2": "25.03.2016 suletud",
    "temp_service_hours_2_until": "25.03.2016",
    "comment_et": null,
    "comment_en": null,
    "comment_ru": null,
    "comment_fi": null,
    "comment_lv": null,
    "comment_lt": null
  }';

$name = 'Location';
$vendor = 'Makecommerce';
$module = 'Omniva';


if ($_SERVER['REQUEST_METHOD'] === 'POST') {

    $json = empty($_POST['json']) ? $_POST['json'] : $json;
    $name = empty($_POST['name']) ? $_POST['name'] : $name;
    $vendor = empty($_POST['vendor']) ? $_POST['vendor'] : $vendor;
    $module = empty($_POST['module']) ? $_POST['module'] : $module;

    $base = "

namespace $vendor\\$module\\Model;
use Magento\\Framework\\Model\\AbstractExtensibleModel;
use $vendor\\$module\\Api\\Data\\{$name}Interface;

class {$name} extends AbstractExtensibleModel implements {$name}Interface
{";


    $json = json_decode($json, true);

    $base .= '    ';

    foreach ($json as $key => $value) {
        $value = strtoupper(preg_replace('|([a-z])([A-Z])|', '$1_$2', $key));
        // $base .= 'const ';
        // $base .= $value;
        // $base .= " = '".$key."';";
        // $base .='
        // ';
        $json[$key] = $value;
    }
// $base .= '
//     /**#@-*/
//     ';


    foreach ($json as $key => $value) {
        $base .= '
    /**
     * {@inheritdoc}
     */
    public function get';
        $base .= ucfirst(preg_replace_callback("/_([a-z])?/", function($match) {
                    return strtoupper($match[1]);
                }, $key));
        $base .='()
    {
        return $this->getData(self::' . $value . ');
    }

    ';
    }

    foreach ($json as $key => $value) {

        $converted = preg_replace_callback("/_([a-z])?/", function($match) {
            return strtoupper($match[1]);
        }, $key);
        $base .= '
    /**
     * {@inheritdoc}
     */
    public function set';
        $base .= ucfirst($converted);
        $base .='( $' . $converted . ' )
    {
        return $this->setData(self::' . $value . ', ' . $converted . ');
    }
    ';
    }


    $base .= '
}';
    echo "<pre>";

    echo $base;
    die;
}
?>

<form method="POST">
    <label for="json">Json</label>
    <textarea id="json" name="json"></textarea><br>
    <label for="name">Name(before Interface) $name.Interface</label>
    <input type="text" name="name" id="name"><br>
    <label for="vendor">Vendor $vendor\$module\Api\Data</label>
    <input type="text" name="vendor" id="vendor"><br>
    <label for="module">Module $vendor\$module\Api\Data</label>
    <input type="module" name="module" id="module"><br>
    <input type="submit"> 
</form>