const express = require("express");
const nodemailer = require("nodemailer");
const fs = require("fs");
const multer = require("multer");
const router = express.Router();

// Setup multer for handling file uploads
const storage = multer.diskStorage({
  destination: function (req, file, cb) {
    cb(null, "./"); // Save to the current directory (you can customize this)
  },
  filename: function (req, file, cb) {
    cb(null, file.originalname); // Use the original file name
  },
});

const upload = multer({ storage });

// Route to handle email sending with file attachment
router.post("/excel", upload.single("file"), async (req, res) => {
  const { teacher, fileName, recipientEmail } = req.body;

  if (!teacher || !fileName || !recipientEmail || !req.file) {
    return res.status(400).json({ error: "Missing required fields or file" });
  }

  // Configure Nodemailer transporter
  const transporter = nodemailer.createTransport({
    service: "gmail",
    auth: {
      user: "swdc.ate@gmail.com", // Replace with your email
      pass: "umlc hbkr dpga iywd", // Replace with your app-specific password or token
    },
    tls: {
      rejectUnauthorized: false, // Ignore self-signed certificate errors
    },
    connectionTimeout: 15000,
    greetingTimeout: 15000,
    socketTimeout: 15000,
  });

  // Email options
  const mailOptions = {
    from: "SWDC Admin <swdc.ate@gmail.com>", // Replace with your email
    to: recipientEmail,
    subject: `Examination Appointments for ${teacher}`,
    text: `Dear Sir/Madam,

Please find attached the Excel sheet regarding various appointments for the May-June 2024 Examination. Kindly find the tick mark (√) for the respective appointments.

Note: Kindly download the Excel sheet to view the hidden columns referring to the Scheme and other information.


If you have any queries, please contact the H.O.D or the Examination In-charge.

Your cooperation regarding the upcoming examination duties is highly solicited.`,
    attachments: [
      {
        filename: fileName,
        path: req.file.path, // Use the uploaded file's path
      },
    ],
  };


  try {
    // Send email
    await transporter.sendMail(mailOptions);
    transporter.close();

    // Delete the temporary file after sending the email
    fs.unlinkSync(req.file.path);

    res.status(200).json({ message: "Email sent successfully" });
  } catch (error) {
    console.error("Error sending email:", error);
    res.status(500).json({ error: "Failed to send email" });
  }
});

// Route to send emails with PDF attachments
router.post("/pdf", upload.single("pdfFile"), async (req, res) => {
  const { fileName, recipientEmail, role, courseName } = req.body;

  if (!fileName || !recipientEmail || !role || !courseName || !req.file) {
    return res.status(400).json({ error: "Missing required fields or file" });
  }

  // Configure Nodemailer transporter
  const transporter = nodemailer.createTransport({
    service: "gmail",
    auth: {
      user: "swdc.ate@gmail.com", // Replace with your email
      pass: "umlc hbkr dpga iywd", // Replace with your app-specific password
    },
    tls: {
      rejectUnauthorized: false,
    },
    connectionTimeout: 15000,
    greetingTimeout: 15000,
    socketTimeout: 15000,
  });

  // Email options
  const mailOptions = {
    from: "SWDC Admin <swdc.ate@gmail.com>",
    to: recipientEmail,
    subject: `Appointment as ${role} - ${courseName}`,
    text: `Dear teacher,

You have been appointed as a ${role} for the course "${courseName}".
Please find your appointment letter attached.

If you have any queries, please contact the Examination In-charge.

Best regards,
Examination Department`,
    attachments: [
      {
        filename: fileName,
        path: req.file.path, // Path to the uploaded PDF
      },
    ],
  };

  try {
    // Send email
    await transporter.sendMail(mailOptions);
    transporter.close();

    // Delete the PDF file after sending
    // fs.unlinkSync(req.file.path);

    res.status(200).json({ message: "Email sent successfully" });
  } catch (error) {
    console.error("Error sending email:", error);
    res.status(500).json({ error: "Failed to send email" });
  }
});

module.exports = router;