const express = require("express");
const fs = require("fs");
const path = require("path");
const { exec } = require("child_process");

const app = express();
app.use(express.json());
app.use(express.static(path.join(__dirname, "public")));

const usersFile = path.join(__dirname, "users.json");
const usersDir = path.join(__dirname, "users");

// Ensure `users.json` and `users/` exist
if (!fs.existsSync(usersFile)) fs.writeFileSync(usersFile, JSON.stringify([]));
if (!fs.existsSync(usersDir)) fs.mkdirSync(usersDir);

// Helper to write logs
function appendLog(username, log) {
  const userLogsDir = path.join(usersDir, username, "logs.txt");
  fs.appendFileSync(userLogsDir, log + "\n");
}

// Endpoint to handle user sign-up
app.post("/signup", (req, res) => {
  const { username, password } = req.body;

  const users = JSON.parse(fs.readFileSync(usersFile));
  if (users.some((user) => user.username === username)) {
    return res.status(400).send("User already exists.");
  }

  users.push({ username, password });
  fs.writeFileSync(usersFile, JSON.stringify(users));

  const userDir = path.join(usersDir, username);
  fs.mkdirSync(userDir);
  fs.writeFileSync(path.join(userDir, "logs.txt"), "");

  res.send("User signed up successfully.");
});

// Endpoint to handle login
app.post("/login", (req, res) => {
  const { username, password } = req.body;

  const users = JSON.parse(fs.readFileSync(usersFile));
  const user = users.find((u) => u.username === username && u.password === password);

  if (!user) {
    return res.status(400).send("Invalid credentials.");
  }

  res.send("Login successful.");
});

// Endpoint to handle terminal commands
app.post("/execute", (req, res) => {
  const { username, command } = req.body;

  const userDir = path.join(usersDir, username);
  if (!fs.existsSync(userDir)) {
    return res.status(400).send("User not found.");
  }

  const child = exec(command, { cwd: userDir });

  child.stdout.on("data", (data) => {
    appendLog(username, data.trim());
  });

  child.stderr.on("data", (data) => {
    appendLog(username, data.trim());
  });

  child.on("close", (code) => {
    appendLog(username, `Process exited with code ${code}`);
  });

  res.send("Command executed.");
});

// Endpoint to get user logs
app.get("/logs", (req, res) => {
  const { username } = req.query;

  const userDir = path.join(usersDir, username);
  if (!fs.existsSync(userDir)) {
    return res.status(400).send("User not found.");
  }

  const logs = fs.readFileSync(path.join(userDir, "logs.txt"), "utf-8");
  res.send(logs);
});

// Endpoint for "Deploy Kaizen"
app.post("/deploy", (req, res) => {
  const { username, repoUrl } = req.body;

  const userDir = path.join(usersDir, username);
  if (!fs.existsSync(userDir)) {
    return res.status(400).send("User not found.");
  }

  // Clear user directory
  fs.rmdirSync(userDir, { recursive: true });
  fs.mkdirSync(userDir);

  const cloneCommand = `git clone ${repoUrl} . && yarn install && yarn start`;

  const child = exec(cloneCommand, { cwd: userDir });

  child.stdout.on("data", (data) => {
    appendLog(username, data.trim());
  });

  child.stderr.on("data", (data) => {
    appendLog(username, data.trim());
  });

  child.on("close", (code) => {
    appendLog(username, `Deploy process exited with code ${code}`);
  });

  res.send("Deployment started.");
});

// Start the server
app.listen(7860, () => {
  console.log("Server running on http://localhost:3000");
});