const express = require('express');
const puppeteer = require('puppeteer-extra');
const StealthPlugin = require('puppeteer-extra-plugin-stealth');
puppeteer.use(StealthPlugin());

const app = express();
const PORT = process.env.PORT || 7860;

// Store browser instance to reuse
let browser = null;

// Middleware
app.use(express.json());

// Delay function to replace waitForTimeout
const delay = (ms) => new Promise(resolve => setTimeout(resolve, ms));

// Initialize browser once on startup
async function initializeBrowser() {
  try {
    console.log('🚀 Initializing browser...');
    
    browser = await puppeteer.launch({
      headless: true, // Set to false for debugging
      args: ["--no-sandbox", "--disable-setuid-sandbox"]
    });

    console.log("✅ Browser initialized successfully!");
    
  } catch (error) {
    console.error("❌ Failed to initialize browser:", error);
    throw error;
  }
}

// Login function for a given page
async function login(page) {
  try {
    console.log('🔐 Checking login status...');
    
    await page.goto("https://getsms.cc/auth/login", {
      waitUntil: "networkidle2"
    });

    // Check if we're already logged in by looking for the #email field
    const isLoginPage = await page.evaluate(() => {
      return !!document.querySelector('#email');
    });

    if (!isLoginPage) {
      console.log('✅ Already logged in, skipping login process.');
      return;
    }

    console.log('🔐 Performing login...');

    // Clear any existing form data
    await page.evaluate(() => {
      const emailInput = document.querySelector('#email');
      const passwordInput = document.querySelector('#password');
      if (emailInput) emailInput.value = '';
      if (passwordInput) passwordInput.value = '';
    });

    // Replace with your actual credentials
    await page.type("#email", "reikernx@gmail.com", { delay: 50 });
    await page.type("#password", "Ogombo12", { delay: 50 });

    await Promise.all([
      page.click("input[type=submit]"),
      page.waitForNavigation({ waitUntil: "networkidle2" })
    ]);

    // Verify login success
    const finalUrl = page.url();
    if (finalUrl.includes('/auth/login')) {
      throw new Error('Login failed - still on login page');
    }

    console.log("✅ Logged in successfully!");
  } catch (error) {
    console.error("❌ Failed to login:", error);
    throw error;
  }
}

// API endpoint to get messages for a phone number
app.get('/api/messages', async (req, res) => {
  let page = null;
  try {
    const { number } = req.query;
    
    if (!number) {
      return res.status(400).json({
        error: 'Phone number is required',
        message: 'Please provide a phone number in the query parameter: ?number=447414848795'
      });
    }

    console.log(`📱 Fetching messages for number: ${number}`);

    // Create a new page for each request
    page = await browser.newPage();

    // Perform login or skip if already logged in
    await login(page);

    // Navigate to the specific info page
    const url = `https://getsms.cc/info/${number}`;
    await page.goto(url, {
      waitUntil: "networkidle2"
    });

    // Verify we didn't get redirected to login page
    const finalUrl = page.url();
    if (finalUrl.includes('/auth/login')) {
      throw new Error('Session invalid - redirected to login page');
    }

    console.log(`✅ Successfully navigated to: ${finalUrl}`);

    // Wait for content to load
    await delay(2000);

    // Extract the latest 5 messages
    const lastMessages = await page.evaluate(() => {
      const messageElements = document.querySelectorAll('.direct-chat-msg');
      
      // Double-check we're not seeing login messages
      const bodyText = document.body.textContent || '';
      if (bodyText.includes('Login to view')) {
        return []; // Return empty array if still showing login message
      }
      
      const messages = Array.from(messageElements).map(msg => {
        const nameElement = msg.querySelector('.direct-chat-name');
        const timeElement = msg.querySelector('.direct-chat-timestamp');
        const textElement = msg.querySelector('.direct-chat-text');
        
        // Skip ads/empty messages
        const text = textElement?.textContent?.trim() || '';
        if (text.includes('adsbygoogle') || text === '' || text.includes('Login to view')) {
          return null;
        }
        
        return {
          sender: nameElement?.textContent?.trim() || 'Unknown',
          time: timeElement?.textContent?.trim() || 'Unknown time',
          message: text
        };
      }).filter(msg => msg !== null); // Remove null entries (ads)
      
      // Return latest 5 messages
      return messages.slice(0, 5);
    });

    // Check if we got empty results due to login requirement
    if (lastMessages.length === 0) {
      const pageContent = await page.evaluate(() => document.body.textContent);
      if (pageContent.includes('Login to view')) {
        throw new Error('Session invalid - still showing "Login to view"');
      }
    }

    console.log(`✅ Found ${lastMessages.length} messages for ${number}`);

    // Return the response
    res.json({
      success: true,
      number: number,
      timestamp: new Date().toISOString(),
      messageCount: lastMessages.length,
      messages: lastMessages
    });

  } catch (error) {
    console.error(`❌ Error fetching messages for ${req.query.number}:`, error);
    res.status(500).json({
      success: false,
      error: 'Failed to fetch messages',
      message: error.message
    });
  } finally {
    // Close the page to avoid memory leaks
    if (page) {
      await page.close();
    }
  }
});

// Health check endpoint
app.get('/api/health', (req, res) => {
  res.json({
    status: 'OK',
    message: 'GetSMS API is running',
    timestamp: new Date().toISOString(),
    browserStatus: browser ? 'Connected' : 'Disconnected'
  });
});

// Get available endpoints
app.get('/', (req, res) => {
  res.json({
    message: 'GetSMS Message Extraction API',
    endpoints: {
      'GET /api/messages?number={phone_number}': 'Get latest 5 messages for a phone number',
      'GET /api/health': 'Check API health status',
      'GET /': 'This help page'
    },
    example: {
      url: '/api/messages?number=447414848795',
      description: 'Get messages for phone number 447414848795'
    }
  });
});

// Graceful shutdown
process.on('SIGINT', async () => {
  console.log('\n🔄 Shutting down gracefully...');
  if (browser) {
    await browser.close();
  }
  process.exit(0);
});

process.on('SIGTERM', async () => {
  console.log('\n🔄 Shutting down gracefully...');
  if (browser) {
    await browser.close();
  }
  process.exit(0);
});

// Start server
async function startServer() {
  try {
    await initializeBrowser();
    
    app.listen(PORT, () => {
      console.log(`\n🌟 GetSMS API Server running on port ${PORT}`);
      console.log(`📋 Available endpoints:`);
      console.log(`   GET http://localhost:${PORT}/api/messages?number=447414848795`);
      console.log(`   GET http://localhost:${PORT}/api/health`);
      console.log(`   GET http://localhost:${PORT}/`);
    });
  } catch (error) {
    console.error('❌ Failed to start server:', error);
    process.exit(1);
  }
}

// Start the server
startServer();