class JsonDiff
{
    public static function compare($before, $after, $id_key, $not_important_keys = [])
    {
        $before = json_decode($before, true);
        $after  = json_decode($after, true);

        $before = self::prepareArray($before, $id_key, $not_important_keys);
        $after  = self::prepareArray($after, $id_key, $not_important_keys);

        $inserted = [];
        $deleted  = [];
        $updated  = [];

        $before_json = array_map('json_encode', $before);
        $after_json  = array_map('json_encode', $after);

        $diff = array_diff_assoc($before_json, $after_json);
        foreach ($diff as $key => $item) {
            if (!isset($after[$key])) {
                $deleted[] = $before[$key];
            } else {
                $updated[$key] = $after[$key];
            }
        }

        $diff = array_diff_assoc($after_json, $before_json);
        foreach ($diff as $key => $item) {
            if (!isset($before[$key])) {
                $inserted[] = $after[$key];
            } elseif (!isset($updated[$key])) {
                $updated[$key] = $before[$key];
            }
        }

        $updated = array_values($updated);

        return json_encode(['inserted' => $inserted, 'updated' => $updated, 'deleted' => $deleted], true);
    }

    protected static function prepareArray($array, $id_key, $not_important_keys)
    {
        $return = [];
        foreach (array_keys($array) as $i) {
            foreach ($array[$i] as $key => $value) {
                if (!in_array($key, $not_important_keys)) {
                    $return[$array[$i][$id_key]][$key] = $value;
                }
            }
        }

        return $return;
    }
}