import { SQSClient, type SendMessageBatchResultEntry } from "@aws-sdk/client-sqs";
import type { Message, ProducerOptions } from "./types.js";
/**
 * [Usage](https://bbc.github.io/sqs-producer/index.html#usage)
 */
export declare class Producer {
    static create: (options: ProducerOptions) => Producer;
    queueUrl: string;
    batchSize: number;
    sqs: SQSClient;
    region?: string;
    constructor(options: ProducerOptions);
    /**
     * Returns the number of messages in the queue.
     * @returns A promise that resolves to the number of messages in the queue.
     */
    queueSize(): Promise<number>;
    /**
     * Send a message to the queue.
     * @param messages - A single message or an array of messages.
     * @returns A promise that resolves to the result of the send operation.
     */
    send(messages: string | Message | (string | Message)[]): Promise<SendMessageBatchResultEntry[]>;
    /**
     * Validate the producer options.
     * @param options - The producer options to validate.
     * @throws Error if any required options are missing or invalid.
     */
    private validate;
    /**
     * Send a batch of messages to the queue.
     * @param failedMessages - An array of failed message IDs.
     * @param successfulMessages - An array of successful message results.
     * @param messages - An array of messages to send.
     * @param startIndex - The index of the first message in the batch.
     * @returns A promise that resolves to the result of the send operation.
     * @throws FailedMessagesError
     */
    private sendBatch;
}