export interface UpdateLifecyclePorts {
  quiesce(): Promise<void>
  restore(): void
  shutdown(): Promise<void>
  exit(): void
  log(error: unknown): void
  prepareTimeoutMs?: number
  quitTimeoutMs?: number
}

export function createUpdateLifecycle(ports: UpdateLifecyclePorts): {
  beforeInstall(): Promise<boolean>
  installFailed(): void
  quitForUpdate(): Promise<void>
} {
  let preparation: Promise<void> | null = null
  let committed = false
  const restore = (): void => { if (!committed) ports.restore() }
  const installFailed = (): void => {
    // Stopping work is not cancellable. Do not resume underneath an old stop.
    if (preparation) void preparation.then(restore, restore)
    else restore()
  }
  return {
    async beforeInstall() {
      if (committed) throw new Error('安装器已启动，请退出应用完成更新')
      if (preparation) throw new Error('上次更新准备仍在结束中，请稍后重试')
      let timer: ReturnType<typeof setTimeout> | undefined
      const pending = ports.quiesce()
      preparation = pending
      void pending.finally(() => { if (preparation === pending) preparation = null }).catch(() => undefined)
      try {
        await Promise.race([
          pending,
          new Promise<never>((_, reject) => {
            timer = setTimeout(() => reject(new Error('任务清理尚未结束，暂不能开始新任务；请稍后重试或重启应用')), ports.prepareTimeoutMs ?? 30_000)
          })
        ])
        return true
      } finally { clearTimeout(timer) }
    },
    installFailed,
    async quitForUpdate() {
      committed = true
      let timer: ReturnType<typeof setTimeout> | undefined
      try {
        await Promise.race([
          ports.shutdown(),
          new Promise<void>(resolve => { timer = setTimeout(resolve, ports.quitTimeoutMs ?? 15_000) })
        ])
      } catch (error) {
        ports.log(error)
      } finally {
        clearTimeout(timer)
        ports.exit()
      }
    }
  }
}