import type { OAuthProvider } from "./interfaces";
export interface GoogleUserInfo {
    googleId: string;
    email: string;
    displayName: string | null;
    photoUrl: string | null;
    emailVerified: boolean;
}
export interface GoogleProviderConfig {
    clientId: string;
    /**
     * The OAuth 2.0 client secret from Google Cloud Console.
     *
     * Required for the **authorization code flow** (Path 3), where the
     * frontend sends an authorization `code` and the backend exchanges it
     * server-side for tokens. This is the most secure flow because tokens
     * never touch the browser.
     *
     * When omitted, only ID-token and access-token verification are available
     * (Paths 1 & 2), which rely on the frontend obtaining tokens directly.
     */
    clientSecret?: string;
}
/**
 * Creates a Google OAuth Provider integration.
 *
 * Supports three verification paths:
 *
 * **Path 1 – ID Token** (One Tap / Sign In With Google button):
 *   Frontend sends `idToken`. Backend verifies cryptographically using
 *   Google's public keys. No secret required.
 *
 * **Path 2 – Access Token** (popup via `initTokenClient`):
 *   Frontend sends `accessToken`. Backend validates by calling Google's
 *   userinfo endpoint. No secret required.
 *
 * **Path 3 – Authorization Code** (most secure, requires `clientSecret`):
 *   Frontend sends `code` + `redirectUri`. Backend exchanges the code
 *   server-side for an ID token using `clientId` + `clientSecret`, then
 *   verifies the ID token. Tokens never touch the browser.
 */
export declare function createGoogleProvider(config: GoogleProviderConfig | string): OAuthProvider<{
    idToken?: string;
    accessToken?: string;
    code?: string;
    redirectUri?: string;
}>;