const express = require("express");
const router = express.Router();
const jwt = require("jsonwebtoken");
const { User } = require("../models");

// Temporary in-memory storage for verification codes
// In production, use Redis or a database
const verificationCodes = new Map();

// Generate random 6-digit code
const generateVerificationCode = () => {
  return Math.floor(100000 + Math.random() * 900000).toString();
};

// Send verification code
router.post("/send-code", async (req, res) => {
  try {
    const { phoneNumber } = req.body;

    if (!phoneNumber) {
      return res.status(400).json({ message: "Phone number is required" });
    }

    // Generate and store verification code
    const code = generateVerificationCode();
    verificationCodes.set(phoneNumber, {
      code,
      createdAt: Date.now(),
      attempts: 0,
    });

    // TODO: Integrate with SMS service (Twilio, AWS SNS, etc.)
    // For development, log the code
    console.log(`Verification code for ${phoneNumber}: ${code}`);

    res.json({
      message: "Verification code sent",
      // Remove this in production - only for development
      devCode: code,
    });
  } catch (error) {
    console.error("Error sending verification code:", error);
    res.status(500).json({ message: "Failed to send verification code" });
  }
});

// Verify code and create/login user
router.post("/verify-code", async (req, res) => {
  try {
    const { phoneNumber, code, firstName, lastName } = req.body;

    if (!phoneNumber || !code) {
      return res
        .status(400)
        .json({ message: "Phone number and code are required" });
    }

    // Check verification code
    const storedData = verificationCodes.get(phoneNumber);

    if (!storedData) {
      return res.status(400).json({
        message: "No verification code found. Please request a new one.",
      });
    }

    // Check if code expired (10 minutes)
    if (Date.now() - storedData.createdAt > 10 * 60 * 1000) {
      verificationCodes.delete(phoneNumber);
      return res.status(400).json({
        message: "Verification code expired. Please request a new one.",
      });
    }

    // Check attempts
    if (storedData.attempts >= 3) {
      verificationCodes.delete(phoneNumber);
      return res.status(400).json({
        message: "Too many failed attempts. Please request a new code.",
      });
    }

    if (storedData.code !== code) {
      storedData.attempts++;
      return res.status(400).json({ message: "Invalid verification code" });
    }

    // Code is valid, remove it
    verificationCodes.delete(phoneNumber);

    // Find or create user
    let user = await User.findOne({ where: { phone: phoneNumber } });

    if (!user) {
      // New user - require firstName and lastName
      if (!firstName || !lastName) {
        return res.status(400).json({
          message: "First name and last name are required for new users",
          isNewUser: true,
        });
      }

      user = await User.create({
        phone: phoneNumber,
        phoneVerified: true,
        firstName,
        lastName,
        authProvider: "phone",
        // Generate a unique username from phone
        username: `user_${phoneNumber
          .replace(/\D/g, "")
          .slice(-6)}_${Date.now().toString(36)}`,
      });
    } else {
      // Existing user - update phone verification
      await user.update({ phoneVerified: true });
    }

    // Generate JWT token
    const token = jwt.sign(
      { id: user.id, phone: user.phone },
      process.env.JWT_SECRET,
      { expiresIn: "7d" }
    );

    res.json({
      message: "Phone verified successfully",
      token,
      user: {
        id: user.id,
        username: user.username,
        firstName: user.firstName,
        lastName: user.lastName,
        phone: user.phone,
        email: user.email,
        phoneVerified: user.phoneVerified,
      },
    });
  } catch (error) {
    console.error("Error verifying code:", error);
    res.status(500).json({ message: "Failed to verify code" });
  }
});

module.exports = router;