import { ClientResponse } from "@sendgrid/client/src/response";
import { ResponseError } from "@sendgrid/helpers/classes";
import { MailDataRequired } from "@sendgrid/helpers/classes/mail";
import { SendGridModuleOptions } from "./sendgrid.interfaces";
export declare class SendGridService {
    private readonly options;
    constructor(options: SendGridModuleOptions);
    send(data: Partial<MailDataRequired> | Partial<MailDataRequired>[], isMultiple?: boolean, cb?: (err: Error | ResponseError, result: [ClientResponse, {}]) => void): Promise<[ClientResponse, {}]>;
    sendMultiple(data: Partial<MailDataRequired>, cb?: (error: Error | ResponseError, result: [ClientResponse, {}]) => void): Promise<[ClientResponse, {}]>;
    private mergeWithDefaultMailData;
}