import { EventEmitter2 } from "@nestjs/event-emitter";
import { DataSource } from "typeorm";
import { GarmrOptions } from "../garmr.options";
import { Authenticatable } from "../interfaces/authenticatable.interface";
/**
 * Provider-specific profile data returned from Google OAuth.
 */
export interface GoogleProfile {
    /** Google account subject identifier */
    sub: string;
    /** Display name from Google account */
    name?: string;
    /** Profile picture URL from Google account */
    picture?: string;
}
/**
 * Result of authenticating via Google OAuth code exchange.
 *
 * @typeParam T - The entity class implementing Authenticatable
 */
export interface GoogleAuthResult<T extends Authenticatable> {
    /** The authenticated or newly created entity */
    entity: T;
    /** True if this was a new registration, false if existing user */
    isNewUser: boolean;
    /** Google profile data extracted from the ID token */
    profile: GoogleProfile;
}
/**
 * Exchanges a Google authorization code for a verified user entity.
 *
 * Follows the same find-or-create-by-email pattern as MagicLinkService.verify():
 * 1. Exchanges the code with Google's token endpoint
 * 2. Decodes the ID token to extract user info
 * 3. Finds an existing user by email or creates a new one
 * 4. Optionally writes Google profile data to the entity
 * 5. Emits registration or authentication events
 *
 * @example
 * ```typescript
 * const result = await googleAuthService.authenticate<User>(code)
 * if (result.isNewUser) {
 *   console.log('New user registered via Google:', result.entity.email)
 * }
 * ```
 */
export declare class GoogleAuthService {
    private readonly options;
    private readonly datasource;
    private readonly eventEmitter;
    private static readonly DEFAULT_TOKEN_ENDPOINT;
    constructor(options: GarmrOptions, datasource: DataSource, eventEmitter: EventEmitter2);
    /**
     * Returns the Google OAuth options, throwing if not configured.
     *
     * @returns The Google OAuth configuration
     * @throws {Error} If googleAuth is not configured in GarmrOptions
     */
    private getGoogleAuth;
    /**
     * Exchanges a Google authorization code for user credentials and finds or
     * creates the corresponding entity.
     *
     * @param code - The authorization code from Google's OAuth redirect
     * @returns Object containing the entity, isNewUser flag, and Google profile
     * @throws {GoogleCodeExchangeException} If Google's token endpoint returns a non-OK HTTP response
     * @throws {GoogleServiceException} If Google's token endpoint returns a 5xx server error
     * @throws {GoogleNetworkException} If the fetch call itself fails (network error, DNS, timeout)
     * @throws {GoogleTokenException} If the ID token is missing, has no email claim, or has no sub claim
     * @throws {EmailNotVerifiedException} If the ID token has email_verified explicitly set to false
     * @throws {Error} If googleAuth is not configured
     *
     * @example
     * ```typescript
     * const { entity, isNewUser, profile } = await googleAuthService.authenticate<User>(code)
     * ```
     *
     * @fires garmr.registered - when a new user is created
     * @fires garmr.authenticated - when an existing user is authenticated
     */
    authenticate<T extends Authenticatable>(code: string): Promise<GoogleAuthResult<T>>;
}