const express = require("express");
const bodyParser = require("body-parser");
const cors = require("cors");
const path = require("path");
const { exec } = require("child_process");
const fs = require("fs-extra");
const { handleTerminal } = require("./terminalManager");
const { 
  isValidDirectoryName, 
  createUserDirectory, 
  deleteUserDirectory,  
  logMessage 
} = require("./utils");

const app = express();

// Middleware
app.use(bodyParser.json());
app.use(cors({
  origin: "*", // For production, replace with specific allowed origins
  methods: ["GET", "POST"],
}));
app.use(express.static(path.join(__dirname, "../frontend")));

const userDirectories = "./userDirectories";

// Ensure userDirectories exists
if (!fs.existsSync(userDirectories)) {
  fs.mkdirSync(userDirectories);
}

const runningProcesses = new Map(); // Tracks running processes

// Root Route
app.get("/", (req, res) => {
  res.sendFile(path.join(__dirname, "../frontend/index.html"));
});

// Start Directory and Terminal
app.post("/start", async (req, res) => {
  const { directoryName, password, repoURL } = req.body;

  try {
    // Validate input
    if (!directoryName || !password || !repoURL) {
      return res.status(400).send("Invalid inputs");
    }

    if (!isValidDirectoryName(directoryName)) {
      return res.status(400).send("Invalid directory name format");
    }

    if (runningProcesses.has(directoryName)) {
      return res.status(400).send("A process is already running for this directory.");
    }

    const userDir = path.join(userDirectories, directoryName);

    // Create user directory
    try {
      createUserDirectory(userDirectories, directoryName, password);
    } catch (err) {
      logMessage(`Failed to create directory: ${err.message}`);
      return res.status(500).send("Failed to create user directory");
    }

    // Clone GitHub repository
    exec(`git clone ${repoURL} ${userDir}`, (cloneError, stdout, stderr) => {
      if (cloneError) {
        logMessage(`Error cloning repo: ${cloneError.message}`);
        logMessage(`STDERR: ${stderr}`);
        return res.status(500).send(`Error cloning repository: ${stderr}`);
      }

      logMessage(`Repository cloned successfully for ${directoryName}`);

      // Install dependencies
      exec(`yarn install --cwd ${userDir}`, (installError, installStdout, installStderr) => {
        if (installError) {
          logMessage(`Error installing dependencies: ${installError.message}`);
          logMessage(`STDERR: ${installStderr}`);
          return res.status(500).send(`Error installing dependencies: ${installStderr}`);
        }

        // Start the terminal process
        handleTerminal(directoryName, userDir);

        // Track the running process
        runningProcesses.set(directoryName, true);

        logMessage(`Successfully initialized directory: ${directoryName}`);
        res.send("Directory and terminal started successfully");
      });
    });

  } catch (error) {
    logMessage(`Error: ${error.message}`);
    res.status(500).send("Internal Server Error");
  }
});

// Delete Directory
app.post("/delete", async (req, res) => {
  const { directoryName, password } = req.body;

  try {
    if (!directoryName || !password) {
      return res.status(400).send("Invalid inputs");
    }

    if (runningProcesses.has(directoryName)) {
      handleTerminal(directoryName, null, true); // Stop terminal
      runningProcesses.delete(directoryName);
    }

    deleteUserDirectory(userDirectories, directoryName, password);
    logMessage(`Directory ${directoryName} deleted successfully`);
    res.send("Directory deleted successfully");
  } catch (error) {
    logMessage(`Error deleting directory: ${error.message}`);
    res.status(500).send(error.message);
  }
});

// Stop Terminal
app.post("/stop", (req, res) => {
  const { directoryName } = req.body;

  if (!directoryName) {
    return res.status(400).send("Invalid directory name");
  }

  if (!runningProcesses.has(directoryName)) {
    return res.status(400).send("No process is running for this directory.");
  }

  handleTerminal(directoryName, null, true); // Stop terminal
  runningProcesses.delete(directoryName);

  logMessage(`Terminal for ${directoryName} stopped`);
  res.send("Terminal stopped successfully");
});

// Server Listener
app.listen(7860, () => console.log("Server is running on port 7860"));