import { OAuth2ClientCredentialsConfiguration } from './types/OAuth2ClientCredentialsConfiguration';
import { OAuth2PasswordConfiguration } from './types/OAuth2PasswordConfiguration';
import { OAuth2TokenResponse } from './types/OAuth2TokenResponse';
/**
 * Represents an OAuth2 client that can retrieve a token from an OAuth2 token URL using either client credentials or a username and password.
 */
export declare class OAuth2Client {
    private readonly oauth2Configuration;
    /**
     * Creates an instance of Oauth2Client.
     * @param {OAuth2PasswordConfiguration | OAuth2ClientCredentialsConfiguration} oauth2Configuration - The OAuth2 configuration to use for retrieving the token.
     */
    constructor(oauth2Configuration: OAuth2PasswordConfiguration | OAuth2ClientCredentialsConfiguration);
    /**
     * Retrieves an OAuth2 token from the OAuth2 token URL using the provided configuration.
     * @returns {Promise<OAuth2TokenResponse>} A promise that resolves to an OAuth2TokenResponse object containing the access token.
     */
    getToken(): Promise<OAuth2TokenResponse>;
    /**
     * Generates a basic authorization string using the OAuth2 client ID and client secret.
     * @returns {string} A string representing the basic authorization header value.
     */
    private generateBasicAuthorization;
    /**
     * Generates the body of the OAuth2 token request based on the provided configuration.
     * @returns {string} A string representing the URL encoded body of the OAuth2 token request.
     */
    private generateOAuth2Body;
    /**
     * Determines if the provided OAuth2 configuration is an instance of OAuth2PasswordConfiguration.
     * @param {unknown} oauth2Configuration - The OAuth2 configuration to check.
     * @returns {oauth2Configuration is OAuth2PasswordConfiguration} A boolean indicating whether the provided configuration is an instance of OAuth2PasswordConfiguration.
     */
    private isOAuth2PasswordConfiguration;
}