const { setJson, getJson } = require('../config/redis');
const { generateOTP } = require('../otpgenerator');
const { generateToken } = require('../util/jwt');
const authService = require('../services/auth.service.js');
const customerController = require('../controllers/customer_details.controller.js');
const { logger } = require('../util/logger');
const axios = require('axios');
const templates = require('../util/sms_template');

// Send OTP
async function SendOtp(req, res) {
  const {
    username,
    mobileNumber,
    type,
    amount,
    beneficiary,
    ifsc,
    acctFrom,
    acctTo,
    ref,
    date,
    userOtp,
    PreferName,
  } = req.body;

  if (!mobileNumber || !type) {
    return res
      .status(400)
      .json({ error: 'Mobile number and type are required' });
  }

  try {
    let message;
    let otp = null;
    // Pick template based on type
    switch (type) {
      case 'LOGIN_OTP':
        otp = generateOTP(6);
        message = templates.LOGIN_OTP(otp, username);
        break;
      case 'IMPS':
        otp = generateOTP(6);
        message = templates.IMPS(otp);
        break;
      case 'NEFT':
        otp = generateOTP(6);
        message = templates.NEFT(otp, amount, beneficiary);
        break;
      case 'RTGS':
        otp = generateOTP(6);
        message = templates.RTGS(otp, amount, beneficiary);
        break;
      case 'BENEFICIARY_ADD':
        otp = generateOTP(6);
        message = templates.BENEFICIARY_ADD(otp, beneficiary, ifsc);
        break;
      case 'BENEFICIARY_SUCCESS':
        message = templates.BENEFICIARY_SUCCESS(beneficiary);
        break;
      case 'BENEFICIARY_DELETE':
        otp = generateOTP(6);
        message = templates.BENEFICIARY_DELETE(otp, beneficiary);
        break;
      case 'NOTIFICATION':
        message = templates.NOTIFICATION(acctFrom, acctTo, amount, ref, date);
        break;
      case 'FORGOT_PASSWORD':
        otp = generateOTP(6);
        message = templates.FORGOT_PASSWORD(otp);
        break;
      case 'CHANGE_LPWORD':
        otp = generateOTP(6);
        message = templates.CHANGE_LPWORD(otp);
        break;
      case 'CHANGE_TPIN':
        otp = generateOTP(6);
        message = templates.CHANGE_TPIN(otp);
        break;
      case 'CHANGE_TPWORD':
        otp = generateOTP(6);
        message = templates.CHANGE_TPWORD(otp);
        break;
      case 'SET_TPWORD':
        otp = generateOTP(6);
        message = templates.SET_TPWORD(otp);
        break;
      case 'CHANGE_MPIN':
        otp = generateOTP(6);
        message = templates.CHANGE_MPIN(otp);
        break;
      case 'REGISTRATION':
        otp = userOtp ? userOtp : generateOTP(6);
        message = templates.REGISTRATION(otp);
        break;
      case 'RIGHT_UPDATE':
        message = templates.RIGHT_UPDATE;
        break;
      case 'EMandate':
        otp = generateOTP(6);
        message = templates.EMandate(otp);
        break;
      case 'USERNAME_UPDATED':
        otp = generateOTP(6);
        message = templates.USERNAME_UPDATED(otp);
        break;
      case 'USERNAME_SAVED':
        message = templates.USERNAME_SAVED(PreferName);
        break;
      case 'TLIMIT':
        otp = generateOTP(6);
        message = templates.TLIMIT(otp);
        break;
      case 'TLIMIT_SET':
        message = templates.TLIMIT_SET(amount);
        break;
      default:
        return res.status(400).json({ error: 'Invalid OTP type' });
    }

    // Call SMS API
    const response = await axios.post(
      'http://localhost:9999/api/SendtoMessage',
      {
        mobileNumber,
        stMessage: message,
      }
    );

    if (response.data) {
      // Save OTP only if it's OTP based (skip notifications without OTP)
      if (message.includes('OTP')) {
        await setJson(`otp:${mobileNumber}`, otp, 300);
      }
      logger.info(`Sent OTP [${otp}] for type [${type}] to ${mobileNumber}`);
    }
    return res.status(200).json({ message: 'Message sent successfully' });
  } catch (err) {
    logger.error(err, 'Error sending OTP');
    return res.status(500).json({ error: 'Internal server error' });
  }
}

// Verify OTP
async function VerifyOtp(req, res) {
  const { mobileNumber } = req.query;
  const { otp } = req.body;

  if (!mobileNumber || !otp) {
    return res.status(400).json({ error: 'Phone number and OTP are required' });
  }

  try {
    const storedOtp = await getJson(`otp:${mobileNumber}`);

    if (!storedOtp) {
      return res.status(400).json({ error: 'OTP expired or not found' });
    }

    if (parseInt(otp, 10) !== parseInt(storedOtp, 10)) {
      return res.status(400).json({ error: 'Invalid OTP' });
    }

    return res.status(200).json({ message: 'OTP verified successfully' });
  } catch (err) {
    logger.error(err, 'Error verifying OTP');
    return res.status(500).json({ error: 'Internal server error' });
  }
}

async function sendForSetPassword(req, res) {
  try {
    const { customerNo } = req.query;
    if (!customerNo)
      return res.status(400).json({ error: 'CUSTOMER_NO_REQUIRED' });
    // check if user is registered for in mobile banking data
    const user = await authService.findUserByCustomerNo(customerNo);
    if (!user) return res.status(404).json({ error: 'USER_NOT_FOUND' });
    // if present then get his phone number from CBS
    const userDetails = await customerController.getDetails(customerNo);
    const singleUserDetail = userDetails[0];
    if (!singleUserDetail?.mobileno)
      return res.status(400).json({ error: 'USER_PHONE_NOT_FOUND' });

    const mobileNumber = singleUserDetail.mobileno;
    const otp = generateOTP(6);
    const message = templates.CHANGE_LPWORD(otp);
    const response = await axios.post(
      'http://localhost:9999/api/SendtoMessage',
      {
        mobileNumber,
        stMessage: message,
      }
    );
    await setJson(`otp:${mobileNumber}`, otp, 300);
    return res.status(200).json({ message: 'OTP_SENT' });
  } catch (err) {
    logger.error(err, 'Error sending OTP');
    return res.status(500).json({ error: 'INTERNAL_SERVER_ERROR' });
  }
}

async function verifyForSetPassword(req, res) {
  try {
    const { customerNo, otp } = req.query;
    if (!customerNo || !otp)
      return res.status(400).json({ error: 'CUSTOMER_NO_REQUIRED' });
    // check if user is registered for mobile banking database
    const user = await authService.findUserByCustomerNo(customerNo);
    if (!user) return res.status(404).json({ error: 'USER_NOT_FOUND' });
    // if present then get his phone number from CBS
    const userDetails = await customerController.getDetails(customerNo);
    // temp check
    const singleUserDetail = userDetails[0];
    if (!singleUserDetail?.mobileno)
      return res.status(400).json({ error: 'USER_PHONE_NOT_FOUND' });

    const mobileNumber = singleUserDetail.mobileno;
    const storedOtp = await getJson(`otp:${mobileNumber}`);

    if (!storedOtp) {
      return res.status(400).json({ error: 'OTP expired or not found' });
    }

    if (parseInt(otp, 10) !== parseInt(storedOtp, 10)) {
      return res.status(400).json({ error: 'Invalid OTP' });
    }

    const token = generateToken(customerNo, 'user', '5m');
    return res
      .status(200)
      .json({ message: 'OTP verified successfully', token: token });
  } catch (err) {
    logger.error(err, 'Error sending OTP');
    return res.status(500).json({ error: 'INTERNAL_SERVER_ERROR' });
  }
}

module.exports = {
  SendOtp,
  VerifyOtp,
  sendForSetPassword,
  verifyForSetPassword,
};