import { type TypeEmailMessage, type TypeEmailMessageResponse, type EmailSenderInterface } from '@messagehub/core';
import type { TypeSendGridConfig } from '../Type/Types.js';
import { ToSendGridEmailMessageTransformer } from '../Transformer/ToSendGridEmailMessageTransformer.js';
import { SendGridRequestSender } from '../RequestSender/SendGridRequestSender.js';
import type { ZodSchema } from 'zod';
/**
 * Email sender implementation for SendGrid.
 */
export declare class SendGridEmailSender implements EmailSenderInterface {
    private requestSender;
    private transformer;
    private schema;
    /**
     * Constructor.
     *
     * @param {TypeSendGridConfig} config - The configuration object for SendGrid.
     * @param {SendGridRequestSender} [requestSender] - The SendGrid API client to use.
     * @param {ToSendGridEmailMessageTransformer} [transformer] - The transformer to use for converting email messages.
     * @param {ZodSchema} [schema] - The schema for the email message.
     */
    constructor(config: TypeSendGridConfig, requestSender?: SendGridRequestSender, transformer?: ToSendGridEmailMessageTransformer, schema?: ZodSchema<TypeEmailMessage>);
    /**
     * Sends an email based on the provided EmailMessage.
     *
     * @param {TypeEmailMessage} message - The email message to be sent.
     * @returns {Promise<TypeEmailMessageResponse>} - The response of the email sending operation.
     */
    send(message: TypeEmailMessage): Promise<TypeEmailMessageResponse>;
    /**
     * Extracts the message ID from SendGrid's response headers.
     *
     * @param {Response} response - The response object from SendGrid.
     * @returns {string} - The extracted message ID.
     */
    private extractMessageId;
}