server.improved.js

const http = require("http"),
  fs = require("fs"),
  // IMPORTANT: you must run `npm install` in the directory for this assignment
  // to install the mime library if you're testing this on your local machine.
  // However, Glitch will install it automatically by looking in your package.json
  // file.
  mime = require("mime"),
  dir = "public/",
  port = 3000;

const appdata = [];

const server = http.createServer(function (request, response) {
  if (request.method === "GET") {
    handleGet(request, response);
  } else if (request.method === "POST") {
    handlePost(request, response);
  }
});

const handleGet = function (request, response) {
  const filename = dir + request.url.slice(1);

  if (request.url === "/") {
    sendFile(response, "public/index.html");
  } else if (request.url === '/list') {
    // Assuming you have a specific endpoint for retrieving the list
    response.writeHead(200, { 'Content-Type': 'application/json' });
    response.end(JSON.stringify(appdata)); 
  } else {
    sendFile(response, filename);
  }
};

const handlePost = function (request, response) {
  let dataString = "";

  request.on("data", function (data) {
    dataString += data;
  });

  request.on("end", function () {
    console.log(JSON.parse(dataString));

    // ... do something with the data here!!!
    const youraction = JSON.parse(dataString).action;

    if (youraction === "delete") {
      const index = JSON.parse(dataString).index;
      if (index >= 0 && index < appdata.length) {
        appdata.splice(index, 1);
      }
    } else if (youraction === "complete") {
      const index = JSON.parse(dataString).index;
      if (index >= 0 && index < appdata.length) {
        if (appdata[index].complete === 'No') {
          appdata[index].complete = 'Yes';
          appdata[index].dateCompleted = new Date().toLocaleString();
        } else {
          appdata[index].complete = 'No';
          appdata[index].dateCompleted = 'Incomplete';
        }
      }   
    } else {
      appdata.push({ action: youraction, date: new Date(), complete: 'No', dateCompleted: 'Incomplete' });
    }

    response.writeHead(200, "OK", { "Content-Type": "text/json" });
    response.end(JSON.stringify(appdata));
  });
};

const sendFile = function (response, filename) {
  const type = mime.getType(filename);

  fs.readFile(filename, function (err, content) {
    // if the error = null, then we've loaded the file successfully
    if (err === null) {
      // status code: https://httpstatuses.com
      response.writeHeader(200, { "Content-Type": type });
      response.end(content);
    } else {
      // file not found, error code 404
      response.writeHeader(404);
      response.end("404 Error: File Not Found");
    }
  });
};

server.listen(process.env.PORT || port);