import { CallbackComponent } from 'systemic'
import { ErrorRequestHandler, Express, RequestHandler } from 'express'

export type AppConfig = {
  settings: Record<string, any>
}

export type ServerConfig = {
  port: number
  host?: string
  shutdown?: { delay?: string }
}

type MiddlewareOptions = {
  notFound?: RequestHandler
  error?: ErrorRequestHandler
}

export type MiddleWareConfig = {
  showErrorDetail?: boolean
}

/**
 * Systemic component that creates and configures an Express app
 * @param options optionally a function that creates a basic Express app can be passed into the component
 */
export function app(options?: { express?: () => Express }): CallbackComponent<Express, { config?: AppConfig; logger?: any }>

/**
 * Starts the Express server
 */
export function server(): CallbackComponent<void, { config: ServerConfig; app: Express; logger?: any }>

/**
 * Adds default notFound and error middleware to the app
 * @param options Custom notfound and error middleware can be passed in. If omitted default middleware will be used.
 */
export function defaultMiddleware(
  options?: MiddlewareOptions,
): CallbackComponent<void, { config?: MiddleWareConfig; app: Express; logger?: any }>