import { Middleware } from 'koa';
import { createReadStream, stat, Stats } from 'fs';

interface IgnoreFunction {
  (path: string): boolean;
}

interface Headers {
  [key: string]: string | string[];
}

interface HeaderFunction {
  (path: string, stats: Stats): Headers | void;
}

interface FileSystem {
  readonly stat: typeof stat;
  readonly createReadStream: typeof createReadStream;
}

export interface Options {
  etag?: boolean;
  fs?: FileSystem;
  defer?: boolean;
  acceptRanges?: boolean;
  lastModified?: boolean;
  ignore?: IgnoreFunction;
  headers?: Headers | HeaderFunction;
}

export default function server(root: string, options?: Options): Middleware;

/**
 * @module server
 * @license MIT
 * @author nuintun
 */

import Koa from 'koa';
import files from 'koa-files';

const app = new Koa();
const port = process.env.PORT || 80;

// Static files server
app.use(
  files('tests', {
    headers: {
      'Cache-Control': 'public, max-age=31557600'
    }
  })
);

/**
 * @function httpError
 * @param {NodeJS.ErrnoException} error
 * @returns {boolean}
 */
function httpError(error) {
  return /^(EOF|EPIPE|ECANCELED|ECONNRESET|ECONNABORTED)$/i.test(error.code);
}

// Listen error event
app.on('error', error => {
  !httpError(error) && console.error(error);
});

// Start server
app.listen(port, () => {
  console.log(`> server running at: 127.0.0.1:${port}`);
});