import bcrypt from "bcryptjs";

import { prisma } from '../lib/prisma'

import {

  generateToken as createJWT,

  generatePasswordResetToken,

  getPasswordResetExpiration,

  isTokenExpired

} from '@app/lib/jwt';

import {

  isValidEmail,

  isValidPassword,

  sanitizeString,

  validateRequiredFields

} from "@app/utils/validators";

import { InvalidEmailError, ShortPasswordError } from '@app/lib/errors/UserErrors'

type UserOptions = {

  email: string;

  firstName: string;

  lastName: string;

};

const createUser = async (email: string, firstName: string, lastName: string, password: string) => {

  // Validate email format

  if (!isValidEmail(email)) {

    throw new InvalidEmailError()

  }

  // Validate password strength

  if (!isValidPassword(password)) {

    throw new ShortPasswordError()

  }

  const encryptedPassword = bcrypt.hashSync(password, 10);

  try {

    const user = await prisma.user.create({

      data: {

        email,

        firstName,

        lastName,

        encryptedPassword

      }

    });

    return user;

  } catch (err: any) {

    throw err;

  }

}

const generateToken = (userId: number, email: string) => {

  return createJWT(userId, email);

}

const findUserById = async (id: number) => {

  return await prisma.user.findUnique({

    where: { id }

  });

};

const findUserByEmail = async (email: string) => {

  return await prisma.user.findUnique({

    where: { email }

  });

};

const authenticateUser = async (email: string, password: string) => {

  const user = await findUserByEmail(email);

  if (!user) {

    throw new Error('Invalid credentials');

  }

  const isPasswordValid = bcrypt.compareSync(password, user.encryptedPassword);

  if (!isPasswordValid) {

    throw new Error('Invalid credentials');

  }

  return user;

};

const initiatePasswordReset = async (email: string) => {

  const user = await findUserByEmail(email);

  if (!user) {

    // Don't reveal whether email exists

    return { success: true };

  }

  const resetToken = generatePasswordResetToken();

  const resetExpires = getPasswordResetExpiration();

  await prisma.user.update({

    where: { id: user.id },

    data: {

      passwordResetToken: resetToken,

      passwordResetExpires: resetExpires

    }

  });

  // In production, send email with reset link

  // For now, return token for testing

  return {

    success: true,

    token: resetToken,

    email: user.email

  };

};

const resetPassword = async (token: string, newPassword: string) => {

  const user = await prisma.user.findFirst({

    where: {

      passwordResetToken: token,

      passwordResetExpires: { not: null }

    }

  });

  if (!user || !user.passwordResetExpires) {

    throw new Error('Invalid or expired reset token');

  }

  if (isTokenExpired(user.passwordResetExpires)) {

    throw new Error('Reset token has expired');

  }

  if (!isValidPassword(newPassword)) {

    throw new ShortPasswordError();

  }

  const encryptedPassword = bcrypt.hashSync(newPassword, 10);

  await prisma.user.update({

    where: { id: user.id },

    data: {

      encryptedPassword,

      passwordResetToken: null,

      passwordResetExpires: null

    }

  });

  return { success: true };

};

const updateUser = async (user: any, data: UserOptions) => {

  return await prisma.user.update({

    where: { id: user.id },

    data

  });

}

export {

  createUser,

  findUserById,

  generateToken,

  findUserByEmail,

  authenticateUser,

  initiatePasswordReset,

  resetPassword,

  updateUser

}