// server.js
const express = require('express');
const session = require('express-session');
const bodyParser = require('body-parser');
const path = require('path');
const fs = require('fs');
const cors = require('cors');

const app = express();
const port = 25570;

// Dynamic CORS configuration: allow requests with or without an Origin header
app.use(cors({
  origin: function (origin, callback) {
    // Allow requests with no origin (like extension or curl requests)
    if (!origin) return callback(null, true);
    callback(null, true);
  },
  credentials: true
}));

// Setup persistent sessions with a 1-week cookie lifetime
app.use(session({
  secret: 'my-secret-key',
  resave: false,
  saveUninitialized: true,
  cookie: { maxAge: 7 * 24 * 60 * 60 * 1000 } // 1 week
}));

// Parse incoming request bodies
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());

// (Optional) Serve static files from "public" if needed
app.use(express.static(path.join(__dirname, 'public')));

// Default route for testing
app.get('/', (req, res) => {
  res.send("Welcome to the NovelSaver server. Please use the POST /api/login endpoint to log in.");
});

// Demo credentials
const demoUsername = "demo";
const demoPassword = "demo";

// In-memory storage for auto update tasks (keyed by session ID)
const userAutoUpdateTasks = {};
// In-memory storage for update logs, now keyed by username (account)
const userUpdatesLog = {};

// Example chapters array (if used elsewhere)
const chapters = [];

// POST /api/login - JSON-based login endpoint (records logs by username)
app.post('/api/login', (req, res) => {
  console.log("Login attempt:", req.body);
  const { username, password } = req.body;
  if (username === demoUsername && password === demoPassword) {
    req.session.username = username;
    // Initialize the user's update log if it doesn't exist.
    if (!userUpdatesLog[username]) {
      userUpdatesLog[username] = [];
    }
    console.log("Login successful for account:", username);
    res.json({ success: true, message: "Logged in successfully" });
  } else {
    console.log("Invalid credentials:", req.body);
    res.status(401).json({ success: false, message: "Invalid credentials" });
  }
});

// GET /api/status - returns the login status
app.get('/api/status', (req, res) => {
  if (req.session.username) {
    res.json({ loggedIn: true, username: req.session.username });
  } else {
    res.json({ loggedIn: false });
  }
});

// POST /record - record the current chapter URL sent by the extension (by account)
app.post('/record', (req, res) => {
  if (!req.session.username) {
    return res.status(401).json({ error: 'Unauthorized' });
  }
  const recordUrl = req.body.url;
  if (!recordUrl) {
    return res.status(400).json({ error: 'URL required' });
  }
  
  // Use the username as the key for the log
  const user = req.session.username;
  if (!userUpdatesLog[user]) {
    userUpdatesLog[user] = [];
  }
  
  // Check if this URL has already been recorded for this account.
  const accountLog = userUpdatesLog[user];
  const alreadyRecorded = accountLog.some(record => record.url === recordUrl);
  if (alreadyRecorded) {
    console.log(`Account ${user}: URL already recorded: ${recordUrl}`);
    return res.json({ success: true, message: 'URL already recorded, ignoring.' });
  }
  
  const updateRecord = {
    account: user,
    url: recordUrl,
    timestamp: new Date().toISOString()
  };
  
  userUpdatesLog[user].push(updateRecord);
  
  fs.appendFile('updates.log', JSON.stringify(updateRecord) + '\n', err => {
    if (err) {
      console.error("Error writing update log:", err);
      return res.status(500).json({ error: 'Logging failed' });
    }
    console.log(`Account ${user} recorded URL: ${recordUrl}`);
    res.json({ success: true, message: 'URL recorded' });
  });
});

// GET /logs - retrieve the update logs for the logged-in account
app.get('/logs', (req, res) => {
  if (!req.session.username) {
    return res.status(401).json({ error: 'Unauthorized' });
  }
  const user = req.session.username;
  res.json({ updates: userUpdatesLog[user] || [] });
});

// GET /logout - logout endpoint (logs persist)
app.get('/logout', (req, res) => {
  if (userAutoUpdateTasks[req.sessionID]) {
    clearInterval(userAutoUpdateTasks[req.sessionID]);
    delete userAutoUpdateTasks[req.sessionID];
  }
  req.session.destroy();
  res.json({ success: true, message: "Logged out" });
});

app.listen(port, () => {
  console.log(`Server running at http://192.168.0.226:${port}`);
});