import { AuthClient, GoogleAuth as AuthLibGoogleAuth, GoogleAuthOptions } from "google-auth-library";
import { GoogleAuth as GaxGoogleAuth } from "google-gax";
export type GcpAuthClient = {
    getAccessToken(): Promise<{
        token: string | null | undefined;
    }>;
    projectId?: string;
    quotaProjectId?: string;
};
export declare abstract class GcpAuthenticatedIdentity {
    protected authLibGoogleAuth: AuthLibGoogleAuth<AuthClient>;
    protected gaxGoogleAuth: GaxGoogleAuth;
    protected options: GoogleAuthOptions;
    constructor(options: GoogleAuthOptions);
    getAccessToken(): Promise<string>;
    abstract getCurrentUserEmail(): Promise<string>;
    getAuthClient(): Promise<AuthLibGoogleAuth<AuthClient>>;
    getGaxAuthClient(): Promise<GaxGoogleAuth>;
    getAuthClientForResourceManager(): Promise<AuthLibGoogleAuth<AuthClient>>;
    getAuthClientForIAM(): Promise<AuthLibGoogleAuth<AuthClient>>;
    getAuthClientForOAuth2(): Promise<AuthLibGoogleAuth<AuthClient>>;
}
export declare class GcpUserAccountIdentity extends GcpAuthenticatedIdentity {
    constructor();
    getCurrentUserEmail(): Promise<string>;
}
export declare class GcpAdcIdentity extends GcpAuthenticatedIdentity {
    constructor();
    getCurrentUserEmail(): Promise<string>;
}
export declare class GcpServiceAccountIdentity extends GcpAuthenticatedIdentity {
    constructor(keyFilePath: string);
    getCurrentUserEmail(): Promise<string>;
}
export type AuthenticationType = "Service Account" | "ADC" | "User Account";
export type AuthenticationContext = {
    forceAuthType?: AuthenticationType;
    serviceAccountPath?: string;
};
export declare function detectAuthenticationType(context?: AuthenticationContext): AuthenticationType;
export declare class GcpIdentityFactory {
    static createIdentity(context?: AuthenticationContext): GcpAuthenticatedIdentity;
    static createAdcIdentity(): GcpAuthenticatedIdentity;
    static createUserIdentity(): GcpAuthenticatedIdentity;
    static createServiceAccountIdentity(keyFilePath: string | undefined): GcpAuthenticatedIdentity;
}