export function promisify<T>(f: (cb: (err: any, res: T) => void) => void, thisContext?: any): () => Promise<T>
export function promisify<A, T>(f: (arg: A, cb: (err: any, res: T) => void) => void, thisContext?: any): (arg: A) => Promise<T>
export function promisify<A, A2, T>(
  f: (arg: A, arg2: A2, cb: (err: any, res: T) => void) => void,
  thisContext?: any
): (arg: A, arg2: A2) => Promise<T>
export function promisify<A, A2, A3, T>(
  f: (arg: A, arg2: A2, arg3: A3, cb: (err: any, res: T) => void) => void,
  thisContext?: any
): (arg: A, arg2: A2, arg3: A3) => Promise<T>
export function promisify<A, A2, A3, A4, T>(
  f: (arg: A, arg2: A2, arg3: A3, arg4: A4, cb: (err: any, res: T) => void) => void,
  thisContext?: any
): (arg: A, arg2: A2, arg3: A3, arg4: A4) => Promise<T>
export function promisify<A, A2, A3, A4, A5, T>(
  f: (arg: A, arg2: A2, arg3: A3, arg4: A4, arg5: A5, cb: (err: any, res: T) => void) => void,
  thisContext?: any
): (arg: A, arg2: A2, arg3: A3, arg4: A4, arg5: A5) => Promise<T>

export function promisify(f: any, thisContext?: any) {
  return function (...a: any[]) {
    const args = Array.prototype.slice.call(a)
    return new Promise(async (resolve, reject) => {
      try {
        args.push((err: any, result: any) => (err ? reject(err) : resolve(result)))
        await f.apply(thisContext, args)
      } catch (e) {
        reject(e)
      }
    })
  }
}