/*!
 * @license
 * Copyright Squiz Australia Pty Ltd. All Rights Reserved.
 */
import { SlackAlertLevel, SlackAlertRequestBody } from './types/SlackClient.types';
export declare class SlackClient {
    private static instance;
    protected static application: string;
    protected static environment: string;
    protected static region: string;
    protected static webhookUrl: string;
    /**
     * Initializes the Slack Client with the required environment vars.
     * @param {string} environment Deployment environment of application.
     * @param {string} region Region application is deployed to 'us' | 'uk' | 'au' as per AWS environment.
     * @param {string} webhookUrl Webhook URL for sending Slack messages.
     * @param {string} application Name of the application.
     */
    static initialize(environment?: string, region?: string, webhookUrl?: string, application?: string): void;
    /**
     * The static method that controls the access to the singleton instance for Slack Client.
     * @returns {SlackClient} The singleton instance.
     */
    static getClient(): SlackClient;
    /**
     * Generate the body of the request for sending to Slack.
     * @param {SlackAlertLevel} level Level associated with alert.
     * @returns {string | null} The icon matching the alert level.
     */
    static getIcon: (level?: SlackAlertLevel) => string | null;
    /**
     * Generate the body of the request for sending to Slack.
     * @param {string} message Message to be sent to Slack channel.
     * @param {SlackAlertLevel} level Level associated with alert.
     * @returns {SlackAlertRequestBody} Slack alert request body.
     */
    static getRequestBody: (message: string, level?: SlackAlertLevel) => SlackAlertRequestBody;
    /**
     * Post a new message/alert to the Webhook URL.
     * @param {string} message Message to be sent.
     * @param {SlackAlertLevel} level Level associated with message.
     */
    sendAlert: (message: string, level?: SlackAlertLevel) => Promise<void>;
}