/**
 * @license Use of this source code is governed by an MIT-style license that
 * can be found in the LICENSE file at https://github.com/cartant/rxjs-interop
 */

import { observable } from "./symbols";
import { InteropObservable } from "./types";

export function patch<T extends InteropObservable<any>>(instance: T): T;
export function patch<T extends new (...args: any[]) => InteropObservable<any>>(
  constructor: T
): T;
export function patch(
  arg: InteropObservable<any> | (new (...args: any[]) => InteropObservable<any>)
): InteropObservable<any> | (new (...args: any[]) => InteropObservable<any>) {
  if (!Symbol.observable) {
    if (
      typeof arg === "function" &&
      arg.prototype &&
      arg.prototype[Symbol.observable]
    ) {
      (arg.prototype as any)[observable] = arg.prototype[Symbol.observable];
      delete arg.prototype[Symbol.observable];
    } else {
      (arg as any)[observable] = arg[Symbol.observable];
      delete arg[Symbol.observable];
    }
  }
  return arg;
}