rsnext/packages/next/client/request-idle-callback.ts

type RequestIdleCallbackHandle = any
type RequestIdleCallbackOptions = {
  timeout: number
}
type RequestIdleCallbackDeadline = {
  readonly didTimeout: boolean
  timeRemaining: () => number
}

declare global {
  interface Window {
    requestIdleCallback: (
      callback: (deadline: RequestIdleCallbackDeadline) => void,
      opts?: RequestIdleCallbackOptions
    ) => RequestIdleCallbackHandle
    cancelIdleCallback: (id: RequestIdleCallbackHandle) => void
  }
}

export const requestIdleCallback =
  (typeof self !== 'undefined' &&
    self.requestIdleCallback &&
    self.requestIdleCallback.bind(window)) ||
  function (
    cb: (deadline: RequestIdleCallbackDeadline) => void
  ): NodeJS.Timeout {
    let start = Date.now()
    return setTimeout(function () {
      cb({
        didTimeout: false,
        timeRemaining: function () {
          return Math.max(0, 50 - (Date.now() - start))
        },
      })
    }, 1)
  }

export const cancelIdleCallback =
  (typeof self !== 'undefined' &&
    self.cancelIdleCallback &&
    self.cancelIdleCallback.bind(window)) ||
  function (id: RequestIdleCallbackHandle) {
    return clearTimeout(id)
  }