import { SentlyError } from "../core/errors.js";
import type { SmsOptions, SmsSendResult, SmsTransport } from "../core/sms-types.js";
import type { VerifyResult } from "../core/types.js";
/** Twilio Messages API configuration. */
export interface TwilioSmsConfig {
    /**
     * Twilio Account SID — always used in the Messages API URL path.
     * Store in environment variables — never hardcode.
     */
    accountSid: string;
    /**
     * Basic-auth password: API Key Secret when {@link apiKey} is set, otherwise Auth Token.
     * Store in environment variables — never hardcode.
     */
    authToken: string;
    /**
     * Optional Twilio API Key SID used as Basic-auth username (recommended in production).
     * When omitted, {@link accountSid} is used as the Basic-auth username.
     */
    apiKey?: string;
    /**
     * Default From phone number, alphanumeric sender ID, short code, or channel address
     * (E.164 recommended, e.g. `+15557654321`). Either this / `options.from` or
     * {@link messagingServiceSid} is required.
     */
    from?: string;
    /**
     * Messaging Service SID (`MG…`). When set and `From` is omitted, Twilio selects
     * the optimal sender from the service's Sender Pool.
     */
    messagingServiceSid?: string;
    /**
     * Optional status callback URL (`StatusCallback`). Twilio POSTs delivery updates here.
     */
    statusCallback?: string;
}
/** Error thrown when the Twilio SMS API returns a non-success response. */
export declare class TwilioSmsError extends SentlyError {
    readonly statusCode: number;
    readonly apiError: unknown;
    /** Creates a Twilio SMS API error with status code and response payload. */
    constructor(message: string, statusCode: number, apiError: unknown);
}
/**
 * Twilio SMS transport via the Messages REST API (form-urlencoded).
 */
export declare class TwilioSmsTransport implements SmsTransport {
    readonly provider = "twilio-sms";
    private readonly accountSid;
    private readonly authToken;
    private readonly apiKey?;
    private readonly from?;
    private readonly messagingServiceSid?;
    private readonly statusCallback?;
    /** Creates a Twilio SMS transport. */
    constructor(config: TwilioSmsConfig);
    /** Sends an SMS via Twilio Messages API. */
    send(options: SmsOptions): Promise<SmsSendResult>;
    /**
     * Validates credentials via Twilio Account fetch
     * (`GET /2010-04-01/Accounts/{AccountSid}.json`).
     */
    verify(): Promise<VerifyResult>;
    private authHeaders;
    private readJson;
}