route.js

const fsPromises = require('fs/promises');
const path = require('path');

const handleHomeRequest = function(request, response) {
   var indexHtml = path.join(__dirname, 'static', 'index.html');

   fsPromises.readFile(indexHtml)
      .then(function(data) {
         response.setHeader('content-type', textType.html);
         response.writeHead(200);
         response.end(data);
      })
      .catch(function(error) {
         console.error(error);
      });
}; // handleHomeRequest

const handlePostRequest = function(request, response) {
   var postHtml = path.join(__dirname, 'static', request.url);

   fsPromises.readFile(postHtml)
      .then(function(data) {
         response.setHeader('content-type', textType.html);
         response.writeHead(200);
         response.end(data);
      })
      .catch(function(error) {
         console.error(error);
         handleOopsRequest(request, response);
      });
}; // handlePostRequest

const handleAssetRequest = function(request, response) {
   var assetFile = path.join(__dirname, 'static', request.url);

   fsPromises.readFile(assetFile)
      .then(function(data) {
         var contentType = textType.get(request.url);
         response.setHeader('content-type', contentType);
         response.writeHead(200);
         response.end(data);
      })
      .catch(function(error) {
         console.error(error);
      });
}; // handleAssetRequest

const handleOopsRequest = function(request, response) {
   var oopsHtml = path.join(__dirname, 'static', 'oops.html');

   fsPromises.readFile(oopsHtml)
      .then(function(data) {
         response.setHeader('content-type', textType.html);
         response.writeHead(404);
         response.end(data);
      })
      .catch(function(error) {
         console.error(error);
      });
}; // handleOopsRequest

const textType = {
   html: 'text/html',
   css: 'text/css',
   js: 'text/javascript',

   get(url) {
      if (url.endsWith('.html'))
         return textType.html;
      else if (url.endsWith('.css'))
         return textType.css;
      else if (url.endsWith('.js'))
         return textType.js;
      else
         return '';
   }
}; // textType

module.exports = {
   handleHomeRequest,
   handlePostRequest,
   handleAssetRequest,
   handleOopsRequest
}; // exports