backend/libs/common/src/util/email.service.ts

import { HttpException, HttpStatus, Injectable } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import * as nodemailer from 'nodemailer';
import axios from 'axios';
import {
  SEND_EMAIL_API_URL_DEV,
  SEND_EMAIL_API_URL_PROD,
} from '../constants/mail-trap';

@Injectable()
export class EmailService {
  private smtpConfig: any;

  constructor(private readonly configService: ConfigService) {
    this.smtpConfig = {
      host: this.configService.get<string>('email-config.SMTP_HOST'),
      port: this.configService.get<number>('email-config.SMTP_PORT'),
      sender: this.configService.get<string>('email-config.SMTP_SENDER'),
      secure: this.configService.get<boolean>('email-config.SMTP_SECURE'), // true for 465, false for other ports
      auth: {
        user: this.configService.get<string>('email-config.SMTP_USER'),
        pass: this.configService.get<string>('email-config.SMTP_PASSWORD'),
      },
    };
  }

  async sendEmail(
    email: string,
    subject: string,
    message: string,
  ): Promise<void> {
    const transporter = nodemailer.createTransport(this.smtpConfig);

    const mailOptions = {
      from: this.smtpConfig.sender,
      to: email,
      subject,
      text: message,
    };

    await transporter.sendMail(mailOptions);
  }
  async sendEmailWithInvitationTemplate(
    email: string,
    emailInvitationData: any,
  ): Promise<void> {
    const isProduction = process.env.NODE_ENV === 'production';
    const API_TOKEN = this.configService.get<string>(
      'email-config.MAILTRAP_API_TOKEN',
    );
    const API_URL = isProduction
      ? SEND_EMAIL_API_URL_PROD
      : SEND_EMAIL_API_URL_DEV;
    const TEMPLATE_UUID = this.configService.get<string>(
      'email-config.MAILTRAP_INVITATION_TEMPLATE_UUID',
    );

    const emailData = {
      from: {
        email: this.smtpConfig.sender,
      },
      to: [
        {
          email: email,
        },
      ],
      template_uuid: TEMPLATE_UUID,
      template_variables: emailInvitationData,
    };

    try {
      await axios.post(API_URL, emailData, {
        headers: {
          Authorization: `Bearer ${API_TOKEN}`,
          'Content-Type': 'application/json',
        },
      });
    } catch (error) {
      throw new HttpException(
        error.response?.data?.message ||
          'Error sending email using Mailtrap template',
        error.response?.status || HttpStatus.INTERNAL_SERVER_ERROR,
      );
    }
  }
  async sendEmailWithTemplate(
    email: string,
    name: string,
    isEnable: boolean,
    isDelete: boolean,
  ): Promise<void> {
    const isProduction = process.env.NODE_ENV === 'production';
    const API_TOKEN = this.configService.get<string>(
      'email-config.MAILTRAP_API_TOKEN',
    );
    const API_URL = isProduction
      ? SEND_EMAIL_API_URL_PROD
      : SEND_EMAIL_API_URL_DEV;

    // Determine the template UUID based on the arguments
    const templateUuid = isDelete
      ? this.configService.get<string>(
          'email-config.MAILTRAP_DELETE_USER_TEMPLATE_UUID',
        )
      : this.configService.get<string>(
          isEnable
            ? 'email-config.MAILTRAP_ENABLE_TEMPLATE_UUID'
            : 'email-config.MAILTRAP_DISABLE_TEMPLATE_UUID',
        );

    const emailData = {
      from: {
        email: this.smtpConfig.sender,
      },
      to: [
        {
          email,
        },
      ],
      template_uuid: templateUuid,
      template_variables: {
        name,
      },
    };

    try {
      await axios.post(API_URL, emailData, {
        headers: {
          Authorization: `Bearer ${API_TOKEN}`,
          'Content-Type': 'application/json',
        },
      });
    } catch (error) {
      throw new HttpException(
        error.response?.data?.message ||
          'Error sending email using Mailtrap template',
        error.response?.status || HttpStatus.INTERNAL_SERVER_ERROR,
      );
    }
  }
  async sendEditUserEmailWithTemplate(
    email: string,
    emailEditData: any,
  ): Promise<void> {
    const isProduction = process.env.NODE_ENV === 'production';
    const API_TOKEN = this.configService.get<string>(
      'email-config.MAILTRAP_API_TOKEN',
    );
    const API_URL = isProduction
      ? SEND_EMAIL_API_URL_PROD
      : SEND_EMAIL_API_URL_DEV;
    const TEMPLATE_UUID = this.configService.get<string>(
      'email-config.MAILTRAP_EDIT_USER_TEMPLATE_UUID',
    );

    const emailData = {
      from: {
        email: this.smtpConfig.sender,
      },
      to: [
        {
          email: email,
        },
      ],
      template_uuid: TEMPLATE_UUID,
      template_variables: emailEditData,
    };

    try {
      await axios.post(API_URL, emailData, {
        headers: {
          Authorization: `Bearer ${API_TOKEN}`,
          'Content-Type': 'application/json',
        },
      });
    } catch (error) {
      throw new HttpException(
        error.response?.data?.message ||
          'Error sending email using Mailtrap template',
        error.response?.status || HttpStatus.INTERNAL_SERVER_ERROR,
      );
    }
  }
  generateUserChangesEmailBody(
    addedSpaceNames: string[],
    removedSpaceNames: string[],
    oldRole: string,
    newRole: string,
    oldName: string,
    newName: string,
  ) {
    const addedSpaceNamesChanged =
      addedSpaceNames.length > 0
        ? `Access to the following spaces were added: ${addedSpaceNames.join(', ')}`
        : '';

    const removedSpaceNamesChanged =
      removedSpaceNames.length > 0
        ? `Access to the following spaces were deleted: ${removedSpaceNames.join(', ')}`
        : '';

    const roleChanged =
      oldRole !== newRole
        ? `Your user role has been changed from [${oldRole}] to [${newRole}]`
        : '';

    const nameChanged =
      oldName !== newName
        ? `The name associated with your account has changed from [${oldName}] to [${newName}]`
        : '';

    return {
      addedSpaceNamesChanged,
      removedSpaceNamesChanged,
      roleChanged,
      nameChanged,
    };
  }
}