import ErrorHander from "../../Utils/errorhander.js";
import catchAsyncErrors from "../../middlewares/catchAsyncErrors.js";
import User from "./userModel.js";
import sendToken from "../../Utils/jwtToken.js";
import sendEmail from "../../Utils/sendEmail.js";
import crypto from "crypto";
import cloudinary from "cloudinary";
import password from "secure-random-password";
import { Order } from "../Orders/orderModel.js";
import { RegisterEmail } from "../EmailCMS/RegisterEmail/registerEmailModal.js";
import { Config } from "../setting/Configration/Config_model.js";
import XLSX from "xlsx";
import fs from "fs";
import path from "path";
import validator from 'validator';
import ShippingAddress from "../ShippingAddresses/ShippingAddressModel.js";

const generatePassword = (name, email) => {
  // Combine name and email, and convert to lowercase
  const combinedStr = (name + email).toLowerCase();

  // Define character pools
  const specialChars = "@#*";
  const numbers = "0123456789";
  const alphaLower = combinedStr.match(/[a-z]/g) || [];
  const alphaUpper = combinedStr.match(/[A-Z]/g) || [];

  // Ensure at least one character from each category
  const specialChar = specialChars.charAt(
    Math.floor(Math.random() * specialChars.length)
  );
  const numberChar = numbers.charAt(Math.floor(Math.random() * numbers.length));
  const lowerChar =
    alphaLower.length > 0
      ? alphaLower[Math.floor(Math.random() * alphaLower.length)]
      : String.fromCharCode(Math.floor(Math.random() * 26) + 97);
  const upperChar =
    alphaUpper.length > 0
      ? alphaUpper[Math.floor(Math.random() * alphaUpper.length)]
      : String.fromCharCode(Math.floor(Math.random() * 26) + 65);

  // Combine required characters
  let passwordChars = [specialChar, numberChar, lowerChar, upperChar];

  // Fill remaining positions with random characters from the combined string
  const allChars = combinedStr + specialChars + numbers;
  while (passwordChars.length < 8) {
    passwordChars.push(
      allChars.charAt(Math.floor(Math.random() * allChars.length))
    );
  }

  // Shuffle characters to ensure randomness
  passwordChars = passwordChars.sort(() => Math.random() - 0.5);

  // Generate password of length 8
  const password = passwordChars.slice(0, 8).join("");

  return password;
};

export const uploadPrincipaldistributors = async (req, res) => {
  try {
    if (!req.files || !req.files.file) {
      return res.status(400).json({ message: "No file uploaded" });
    }

    const file = req.files.file;
    const filePath = path.join("public", "uploads", file.name);

    // Ensure 'uploads' directory exists
    if (!fs.existsSync(path.dirname(filePath))) {
      fs.mkdirSync(path.dirname(filePath), { recursive: true });
    }

    // Move the file from temp to the uploads directory
    await file.mv(filePath);

    // Process the file
    const fileBuffer = fs.readFileSync(filePath);
    const workbook = XLSX.read(fileBuffer, { type: "buffer" });
    const sheetName = workbook.SheetNames[0];
    const worksheet = workbook.Sheets[sheetName];
    const data = XLSX.utils.sheet_to_json(worksheet, { header: 1 });

    if (data.length <= 1) {
      return res.status(400).json({ message: "Empty spreadsheet or no data found" });
    }

    const headers = data[0];

    // Map headers from the Excel file to your schema
    const headerMapping = {
      "Principal Distributor Name": "name",
      "Email": "email",
      "Phone Number": "phone",
      "PAN Number": "panNumber",
      "Trade Name": "tradeName",
      "GST Number": "gstNumber",
      "State": "state",
      "City": "city",
      "Street": "street",
      "Pincode": "postalCode",
    };

    const requiredHeaders = Object.keys(headerMapping);

    if (!requiredHeaders.every((header) => headers.includes(header))) {
      return res.status(400).json({ message: "Missing required columns in spreadsheet" });
    }

    const errors = [];
    const newlyCreated = [];
    const updatedDistributors = [];

    for (let i = 1; i < data.length; i++) {
      const row = data[i];
      const item = {};

      headers.forEach((header, index) => {
        if (headerMapping[header]) {
          item[headerMapping[header]] = row[index] !== undefined ? row[index] : "";
        }
      });

      // Initialize error tracking for each item
      const missingFields = new Set();
      const validationErrors = new Set();

      // Validate required fields
      if (!item.name) missingFields.add("name");
      if (!item.email) missingFields.add("email");
      if (!item.phone) missingFields.add("phone");
      if (!item.panNumber) missingFields.add("panNumber");
      if (!item.tradeName) missingFields.add("tradeName");
      if (!item.gstNumber) missingFields.add("gstNumber");
      if (!item.state) missingFields.add("state");
      if (!item.city) missingFields.add("city");
      if (!item.street) missingFields.add("street");
      if (!item.postalCode) missingFields.add("postalCode");

      // Check email validity
      if (item.email && !validator.isEmail(item.email)) {
        validationErrors.add("incorrect mail");
      }

      // Validate mobile number
      if (item.phone && !/^\d{10}$/.test(item.phone)) {
        validationErrors.add("Invalid Mobile Number (should be 10 digits)");
      }

      // Check GST, PAN, and postal code validation
      item.panNumber = item.panNumber ? item.panNumber.toUpperCase() : "";
      item.gstNumber = item.gstNumber ? item.gstNumber.toUpperCase() : "";

      // Validate PAN Number
      if (item.panNumber && !/^[A-Z]{5}[0-9]{4}[A-Z]{1}$/.test(item.panNumber)) {
        validationErrors.add("Invalid PAN Number");
      }

      // Validate GST Number
      if (item.gstNumber && !/^(\d{2}[A-Z]{5}\d{4}[A-Z]{1}\d[Z]{1}[A-Z\d]{1})$/.test(item.gstNumber)) {
        validationErrors.add("Invalid GST Number");
      }

      // Validate Postal Code
      if (item.postalCode && !/^\d{6}$/.test(item.postalCode)) {
        validationErrors.add("Invalid Postal Code");
      }

      // Combine all errors into a single message
      let errorMessage = "";
      if (missingFields.size > 0) {
        errorMessage += `Missing fields: ${Array.from(missingFields).join(", ")}. `;
      }
      if (validationErrors.size > 0) {
        errorMessage += `Validation errors: ${Array.from(validationErrors).join(", ")}.`;
      }

      // If there are errors, push them to the errors array
      if (errorMessage.trim()) {
        errors.push({
          name: item.name || "N/A",
          email: item.email || "N/A",
          phone: item.phone || "N/A",
          panNumber: item.panNumber || "N/A",
          gstNumber: item.gstNumber || "N/A",
          message: errorMessage.trim(),
        });
        continue;
      }

      // Generate a password
      const password = generatePassword(item.name, item.email);
      item.role = "principal-Distributor";
      const currentYear = new Date().getFullYear().toString().slice(-2);
      const randomChars = crypto.randomBytes(4).toString("hex").toUpperCase();
      item.uniqueId = `${currentYear}-${randomChars}`;

      // Check for existing user
      let user = await User.findOne({ email: item.email });

      if (user) {
        // Track updated fields
        const updatedFields = [];
        const addressFields = ['panNumber', 'gstNumber', 'state','city', 'street', 'tradeName', 'postalCode'];
        const existingAddress = await ShippingAddress.findOne({ user: user._id });

        // Check for changes in user details
        let userUpdated = false;
        if (user.name !== item.name) {
          updatedFields.push("name");
          user.name = item.name;
          userUpdated = true;
        }
        if (user.phone !== item.phone.toString()) {
          updatedFields.push("phone");
          user.phone = item.phone;
          userUpdated = true;
        }

        // Update user
        if (userUpdated) {
          await user.save();
        }

        // Check for changes in address details
        const addressData = {
          street: item.street,
          city: item.city,
          state: item.state,
          postalCode: item.postalCode.toString(),
          country: "India", // Default country
          panNumber: item.panNumber,
          tradeName: item.tradeName,
          gstNumber: item.gstNumber,
          user: user._id,
        };

        let addressUpdated = false;
        if (existingAddress) {
          const addressUpdates = [];
          addressFields.forEach(field => {
            if (existingAddress[field] !== addressData[field]) {
              addressUpdates.push(field);
              addressUpdated = true;
            }
          });

          if (addressUpdated) {
            await ShippingAddress.updateOne({ user: user._id }, addressData);
            if (addressUpdates.length > 0) {
              updatedFields.push(`Address fields: ${addressUpdates.join(", ")}`);
            }
          }
        } else {
          // Create new address
          await ShippingAddress.create(addressData);
          updatedFields.push("New address created");
        }

        // Add to updatedDistributors only if there are updated fields
        if (updatedFields.length > 0) {
          updatedDistributors.push({
            ...user._doc,
            updatedFields: updatedFields.join(", ")
          });
        }
      } else {
        // Create a new user
        user = new User({
          name: item.name,
          email: item.email,
          phone: item.phone,
          password,
          role: item.role,
          uniqueId: item.uniqueId,
        });
        await user.save();

        // Send email with the new user details
        await sendEmail({
          to: item.email,
          from: process.env.SEND_EMAIL_FROM,
          subject: `Cheminova Account Created`,
          html: `
            Your Principal Distributor Account is created successfully.
            <br/>Name: <strong>${item.name}</strong><br/>
            <br/>Mobile Number: <strong>${item.phone}</strong><br/>
            <br/>Password: <strong>${password}</strong><br/><br/>
            <a href="${process.env.PD_APP_URL}/login">Click here to login</a><br/><br/>
            If you have not requested this email, please ignore it.
          `,
        });

        newlyCreated.push(user._doc);
      }
    }

    fs.unlinkSync(filePath); // Clean up uploaded file

    res.status(201).json({
      message:
        errors.length > 0
          ? "File processed with errors!"
          : "File processed successfully!",
      processedUsers: {
        newlyCreated: newlyCreated.length,
        updatedDistributors: updatedDistributors.length
      },
      errors,
      newlyCreated,
      updatedDistributors
    });
  } catch (error) {
    console.error("Error processing file:", error);
    res.status(500).json({ message: "Internal server error" });
  }
};

// 1.Register a User
// export const registerUser = async (req, res) => {
//   try {
//     const { name, email, password, phone, accessTo, role } = req.body;
//     // console.log("this is the password ", password, name, req.body);

//     let findUser = await User.findOne({ email });
//     if (findUser) {
//       return res
//         .status(400)
//         .json({ success: false, message: "User already exists" });
//     }
//     if (req.files) {
//       const files = req.files.avatar;
//       const myCloud = await cloudinary.uploader.upload(
//         files.tempFilePath,
//         {
//           folder: "Cheminova/user-image",
//         },
//         function (error, result) {
//           result, error;
//         }
//       );
//     }

//     const user = await User.create({
//       name,
//       email,
//       password,
//       phone,
//       role,
//       accessTo,
//       // avatar: {
//       //     public_id: myCloud.public_id,
//       //     url: myCloud.secure_url,
//       // },
//     });
//     // const emailData = await RegisterEmail.find();
//     // let emailSubject = emailData[0]?.subject;
//     // let emailDescription = emailData[0]?.description;
//     const config = await Config.find();
//     let appName = config[0]?.appName;

//     //   await sendEmail({
//     //     to: `${email}`, // Change to your recipient

//     //     from: `${process.env.SEND_EMAIL_FROM}`, // Change to your verified sender

//     //     subject: `Welcome to Cheminova - Let the Shopping Begin!`,
//     //     html: ` <h1 style="color: #333; text-align: left; font-family: Arial, sans-serif;">Welcome to ${appName} - Let the Shopping Begin!</h1>
//     //      <strong style="color: #1b03a3; font-size: 16px"> Hey ${name},</strong>

//     //      <p style="color: #555; font-size: 15px;">

//     //         Welcome to Cheminova - Let the Shopping Begin!
//     //      </p>
//     //      <br/>
//     //      <p style="color: #555; font-size: 15px;">You can login into :${role === "Employee" || role === "admin"
//     //         ? `https://admin.smellika.com/`
//     //         : `https://smellika.com`
//     //       } </p>
//     //       <br/>
//     //       <p style="color: #555; font-size: 15px;">Below are your login credentials:</p>
//     // <p style="color: #555; font-size: 15px;">Email: ${email}</p>
//     // <p style="color: #555; font-size: 15px;">Password: ${password}</p>
//     //       <span style="color: #555; font-size: 13px;">Happy shopping,</span><br/>

//     //       <span style="color: #555; font-size: 13px;">Team ${appName}</span>`,
//     //   });
//     sendToken(user, 201, res);
//   } catch (e) {
//     return res.status(400).json({ success: false, message: e.message });
//   }
// };
export const registerUser = async (req, res) => {
  try {
    const { name, email, phone, accessTo, role } = req.body;
    // console.log(req.body);
    const password = generatePassword(name, email);
    // console.log(password);
    // Check if user already exists
    let user = await User.findOne({ email });
    if (user) {
      // If user exists, update their details if needed
      user.name = name;
      // user.password = password; // In a real application, you should hash this
      user.phone = phone;
      user.role = role;
      user.accessTo = accessTo;

      // Save updates
      await user.save();
      // console.log("finduser", user);
      // Respond with success and userId
      return res.status(200).json({
        success: true,
        message: "User updated successfully",
        userId: user._id,
      });
    }

    // Create a new user if not found
    user = new User({
      name,
      email,
      password,
      phone,
      role,
      accessTo,
    });
    // console.log(user);
    // Generate uniqueId
    const currentYear = new Date().getFullYear().toString().slice(-2);
    const randomChars = crypto.randomBytes(4).toString("hex").toUpperCase();
    user.uniqueId = `${currentYear}-${randomChars}`;

    // Save the new user to the database
    await user.save();

    // Send email with the new user details
    if (user.role === "principal-Distributor") {
      await sendEmail({
        to: email,
        from: process.env.SEND_EMAIL_FROM,
        subject: `Cheminova Account Created`,
        html: `
          Your Principal Distributor Account is created successfully.
          <br/>Name: <strong>${name}</strong><br/>
          <br/>Mobile Number: <strong>${phone}</strong><br/>
          <br/>Password: <strong>${password}</strong><br/><br/>
          <a href="${process.env.PD_APP_URL}/login">Click here to login</a><br/><br/>
          If you have not requested this email, please ignore it.
        `,
      });
    }

    // Respond with success and userId
    res.status(201).json({
      success: true,
      message: "User created successfully",
      userId: user._id,
    });
  } catch (error) {
    console.error(error);
    res.status(400).json({ success: false, message: error.message });
  }
};

// 2.Login User
export const loginUser = async (req, res, next) => {
  const { email, password } = req.body;
  // checking if user has given password and email both

  try {
    if (!email || !password) {
      return res.status(400).json({ message: "Please Enter Email & Password" });
    }

    const user = await User.findOne({ email }).select("+password");

    if (!user) {
      return res.status(400).json({ message: "Invalid Email or Password" });
    }

    const isPasswordMatched = await user.comparePassword(password);

    if (!isPasswordMatched) {
      return res.status(400).json({ message: "Invalid Email or Password" });
    }

    sendToken(user, 200, res);
  } catch (error) {
    return res
      .status(500)
      .json({ message: "Something went wrong!", error: error?.message || "" });
  }
};

// 3.Logout User
export const logout = catchAsyncErrors(async (req, res, next) => {
  res.cookie("token", null, {
    expires: new Date(Date.now()),
    httpOnly: true,
  });

  res.status(200).json({
    success: true,
    message: "Logged Out",
  });
});

// 4.Forgot Password

export const forgotPassword = async (req, res, next) => {
  const user = await User.findOne({ email: req.body.email });

  if (!user) {
    return res.status(404).json({ message: "User not found" });
  }
  // Get ResetPassword Token
  const resetToken = user.getResetPasswordToken(); //call function

  //save database reset token
  await user.save({ validateBeforeSave: false });

  const passwords = password.randomPassword({
    length: 12,
    characters: [
      { characters: password.upper, exactly: 1 },
      { characters: password.symbols, exactly: 1 },
      password.lower,
      password.digits,
    ],
  });

  user.password = passwords;
  await user.save();
  // const message = `Your password reset token are :- \n\n ${resetPasswordUrl} \n\nyour new password is:${password}\n\nIf you have not requested this email then, please ignore it.`;
  try {
    await sendEmail({
      to: `${user.email}`, // Change to your recipient

      from: `${process.env.SEND_EMAIL_FROM}`, // Change to your verified sender

      subject: `Cheminova Password Recovery`,
      html: `your new password is: <br/> <strong> ${passwords}</strong><br/><br/>If you have not requested this email then, please ignore it.`,
    });

    res.status(200).json({
      success: true,
      message: `Email sent to ${user.email} successfully`,
    });
  } catch (error) {
    user.resetPasswordToken = undefined;
    user.resetPasswordExpire = undefined;

    await user.save({ validateBeforeSave: false });

    return res
      .status(500)
      .json({ message: "Something went wrong!", error: error?.message || "" });
  }
};

// 5.Reset Password
export const resetPassword = catchAsyncErrors(async (req, res, next) => {
  // creating token hash
  const resetPasswordToken = crypto
    .createHash("sha256")
    .update(req.params.token)
    .digest("hex");

  const user = await User.findOne({
    resetPasswordToken,
    resetPasswordExpire: { $gt: Date.now() },
  });

  if (!user) {
    return next(
      new ErrorHander(
        "Reset Password Token is invalid or has been expired",
        400
      )
    );
  }
  //replace previous password
  if (req.body.password !== req.body.confirmPassword) {
    return next(new ErrorHander("Password does not password", 400));
  }

  user.password = req.body.password;
  user.resetPasswordToken = undefined;
  user.resetPasswordExpire = undefined;

  await user.save();

  sendToken(user, 200, res);
});

//6.Get User Detail
export const getUserDetails = catchAsyncErrors(async (req, res, next) => {
  const user = await User.findById(req.user.id);

  res.status(200).json({
    success: true,
    user,
  });
});

// export const getUserDetailsForAdmin = catchAsyncErrors(
//   async (req, res, next) => {
//     const user = await User.findById(req.params._id);

//     res.status(200).json({
//       success: true,
//       user,
//     });
//   }
// );

// export const getAllUsers = catchAsyncErrors(async (req, res, next) => {
//   const users = await User.find().populate("orders"); // Assuming orders are stored in a separate collection and populated in the User model

//   // Process user data to calculate last purchase date and order count
//   const usersWithInfo = users.map((user) => {
//     const lastPurchase =
//       user.orders.length > 0
//         ? user.orders[user.orders.length - 1].createdAt
//         : null;
//     const orderCount = user.orders.length;
//     return { ...user.toJSON(), lastPurchase, orderCount };
//   });

//   res.status(200).json({
//     success: true,
//     users: usersWithInfo,
//   });
// });

// 7.Get single user (admin)
export const getSingleUser = catchAsyncErrors(async (req, res, next) => {
  if (!req.params.id) {
    return next(new ErrorHander(`please send User ID`, 404));
  }
  const user = await User.findById(req.params.id);

  if (!user) {
    return next(
      new ErrorHander(`User does not exist with Id: ${req.params.id}`, 404)
    );
  }

  res.status(200).json({
    success: true,
    user,
  });
});
export const getUserOrderForAdmin = async (req, res) => {
  const id = req.params.id;
  // console.log(id);
  try {
    const order = await Order.find({
      user: id,
      // payment_status: "success",
    }).sort({ createdAt: -1 });

    if (order) {
      return res.status(200).json({
        success: true,
        order,
        message: "self Order fetched",
      });
    }
  } catch (error) {
    res.status(500).json({
      success: false,
      message: error.message ? error.message : "Something went Wrong",
    });
  }
};
// 8.update User password
export const updatePassword = catchAsyncErrors(async (req, res, next) => {
  const user = await User.findById(req.user.id).select("+password");

  const isPasswordMatched = await user.comparePassword(req.body.oldPassword);

  if (!isPasswordMatched) {
    return res.status(400).json({ message: "Old password is incorrect" });
  }

  if (req.body.newPassword !== req.body.confirmPassword) {
    return res
      .status(400)
      .json({ message: "New Password and Confirm Password do not match" });
  }

  user.password = req.body.newPassword;
  await user.save();

  sendToken(user, 200, res);
});

// 9.update User Profile
export const updateProfile = catchAsyncErrors(async (req, res, next) => {
  const newUserData = {
    name: req.body.name,
    phone: req.body.phone,
    email: req.body.email,
  };

  // if (req.files) {
  //     const userImage = req.files?.avatar;
  //     const user = await User.findById(req.user.id);

  //     if (user?.avatar) {
  //         const imageId = user?.avatar?.public_id;

  //         await cloudinary.uploader.destroy(imageId)
  //     }

  //     const myCloud = await cloudinary.v2.uploader.upload(userImage.tempFilePath,
  //         {
  //             folder: "Cheminova/user-image",

  //         });

  //     newUserData.avatar = {
  //         public_id: myCloud.public_id,
  //         url: myCloud.secure_url,
  //     };
  // }

  const user = await User.findByIdAndUpdate(req.user.id, newUserData, {
    new: true,
    runValidators: true,
    useFindAndModify: false,
  });

  return res.status(200).json({
    success: true,
    user,
  });
});

// 9.Get all users(admin)
export const getAllUser = catchAsyncErrors(async (req, res, next) => {
  // Assuming your User model is imported as 'User'
  const users = await User.find({ role: "principal-Distributor" });

  res.status(200).json({
    success: true,
    users,
  });
});
export const getAllEmployee = catchAsyncErrors(async (req, res, next) => {
  // Assuming your User model is imported as 'User'
  const employee = await User.find({ role: "Employee" });

  res.status(200).json({
    success: true,
    employee,
  });
});
export const deleteEmployeeById = catchAsyncErrors(async (req, res, next) => {
  // console.log("request came here", req.params);
  // Extract the employee ID from the request parameters
  const { id } = req.params;

  try {
    // Find the employee by ID and delete it
    const deletedEmployee = await User.findByIdAndDelete(id);

    if (!deletedEmployee) {
      // If the employee with the provided ID is not found, return an error
      return res.status(404).json({
        success: false,
        message: "Employee not found",
      });
    }

    // If deletion is successful, return success response
    res.status(200).json({
      success: true,
      message: "Employee deleted successfully",
    });
  } catch (error) {
    // Handle any errors that occur during deletion
    return res.status(500).json({
      success: false,
      message: "Error deleting employee",
      error: error.message,
    });
  }
});
// Update employee
// Import necessary modules and set up your User model

export const updateEmployeeById = catchAsyncErrors(async (req, res, next) => {
  // Extract the employee ID from the request parameters
  const { id } = req.params;

  try {
    // Find the employee by ID and update its fields
    const updatedEmployee = await User.findByIdAndUpdate(
      id,
      { $set: req.body }, // Update fields based on the request body
      { new: true } // Return the updated document
    );

    if (!updatedEmployee) {
      // If the employee with the provided ID is not found, return an error
      return res.status(404).json({
        success: false,
        message: "Employee not found",
      });
    }

    // If update is successful, return success response with updated employee data
    res.status(200).json({
      success: true,
      message: "Employee updated successfully",
      employee: updatedEmployee,
    });
  } catch (error) {
    // Handle any errors that occur during update
    return res.status(500).json({
      success: false,
      message: "Error updating employee",
      error: error.message,
    });
  }
});