/**
 * Helper function to convert callbacks into promises
 * @param func
 */

export default function callbackify(
  func: (...args: any[]) => Promise<any>
): Function {
  return (...args: any[]) => {
    const onlyArgs: any[] = [];
    let maybeCallback: Function | null = null;

    for (const arg of args) {
      if (typeof arg === "function") {
        maybeCallback = arg;
        break;
      }

      onlyArgs.push(arg);
    }

    if (!maybeCallback) {
      throw new Error("Missing callback parameter!");
    }

    const callback = maybeCallback;

    func(...onlyArgs)
      .then((data: any) => callback(null, data))
      .catch((err: any) => callback(err));
  };
}