add solution

src/createServer.js

@@ -1,8 +1,61 @@
 'use strict';
 
+const http = require('http');
+const { IncomingForm } = require('formidable');
+const fs = require('fs');
+
 function createServer() {
   /* Write your code here */
   // Return instance of http.Server class
+  return http.createServer(async (req, res) => {
+    if (req.method === 'POST' && req.url === '/add-expense') {
+      const form = new IncomingForm({ multiples: false });
+
+      try {
+        const [fields] = await form.parse(req);
+
+        const { date, title, amount } = fields;
+
+        if (!date || !title || !amount) {
+          res.writeHead(400, { 'Content-Type': 'text/plain' });
+
+          return res.end('Missing required fields');
+        }
+
+        const result = JSON.stringify(fields);
+
+        // console.log('Fields:', fields);
+
+        fs.writeFileSync('db/expense.json', result);
+
+        res.writeHead(200, { 'Content-Type': 'application/json' });
+        res.end(result);
+
+        // res.end(`<div>
+        //   <h1>Date: ${fields['date']}</h1>
+        //   <h1>Title: ${fields['title']}</h1>
+        //   <h1>Amount: ${fields['amount']}</h1>
+        //   </div`);
+      } catch (err) {
+        res.writeHead(500);
+        res.end('Error parsing form');
+      }
+    } else if (req.method === 'GET' && req.url === '/') {
+      res.statusCode = 200;
+      res.setHeader('Content-type', 'text/html');
+
+      res.end(`<form method="POST" action="/submit-expense" enctype="multipart/form-data">
+        <input name="date" type="date" required>
+        <input name="title" type="text" required>
+        <input name="amount" type="number" required>
+
+        <button type="submit">Submit</button>
+      </form>`);
+    } else {
+      res.statusCode = 404;
+      res.end('Page not found');
+    }
+  });
 }
 
 module.exports = {