import { Queue } from 'bull';
import Mail from 'nodemailer/lib/mailer';
import { MailerOptions } from '../interfaces/mailer-options.interface';
import { BaseMail } from '../mails/base.mail';
import { MailContentService } from './mail-content.service';
export declare class MailService {
    private mailerOptions;
    private mailContentService;
    private mailQueue;
    private logger;
    private transport;
    constructor(mailerOptions: MailerOptions, mailContentService: MailContentService, mailQueue: Queue);
    addToQueue(mail: BaseMail): Promise<void>;
    send(mail: BaseMail): Promise<void | undefined>;
    sendToTransport(options: Mail.Options): Promise<void | undefined>;
    private getMailOptions;
    private getNodeMailerOptions;
    private getValidReceivers;
    private stringifyEmails;
    private logException;
}