export interface BackendIdentity {
    userId: string;
    gameId: string;
}
export interface SqlBinding {
    query<T = unknown>(text: string, parameters?: readonly unknown[]): Promise<T[]>;
    transaction<T>(callback: (sql: SqlBinding) => Promise<T>): Promise<T>;
}
export interface RedisBinding {
    get<T = unknown>(key: string): Promise<T | null>;
    set(key: string, value: unknown, options?: {
        ttlSeconds?: number;
    }): Promise<void>;
    delete(key: string): Promise<void>;
}
export interface BackendMediaSessionRequest {
    roomId: string;
    channel: string;
    media: 'audio' | 'video';
    maxPlayers: number;
    mode?: 'auto' | 'p2p' | 'sfu';
    userId: string;
}
export interface BackendMediaBinding {
    createSession(input: BackendMediaSessionRequest): Promise<{
        roomId: string;
        mediaSessionId: string;
        mode: 'p2p' | 'sfu';
        iceServers: RTCIceServer[];
        expiresAt: number;
        sfu?: {
            url: string;
            token: string;
            managedIce?: boolean;
        };
    }>;
}
export interface GameBackendContext {
    identity: BackendIdentity;
    gameId: string;
    /** Stable deployment identity. It does not change between artifact releases. */
    backendDeploymentId: string;
    /** Immutable artifact digest for the code currently running in this Runner. */
    version: string;
    sql: SqlBinding;
    redis: RedisBinding;
    /** Platform-issued short-lived TURN/SFU credentials; the signing secrets remain outside game code. */
    media: BackendMediaBinding;
}
export type GameBackendHandler = (request: Request, context: GameBackendContext) => Response | Promise<Response>;
export interface GameBackendSocket {
    send(data: unknown): void;
    close(code?: number, reason?: string): void;
    onMessage(handler: (data: unknown) => void): () => void;
    onClose(handler: (event: unknown) => void): () => void;
}
export type GameBackendWebSocketHandler = (socket: GameBackendSocket, context: GameBackendContext) => void | Promise<void>;
export type BackendProtocol = 'http' | 'websocket' | 'http-websocket';
export interface GameBackendManifest {
    protocol?: BackendProtocol;
    [key: string]: unknown;
}
export interface GameBackendDefinition {
    fetch?: GameBackendHandler;
    websocket?: GameBackendWebSocketHandler;
    manifest?: GameBackendManifest;
}
/** Defines a game-owned HTTP, WebSocket, or dual-protocol backend. */
export declare function defineGameBackend(handler: GameBackendHandler | {
    http?: GameBackendHandler;
    websocket?: GameBackendWebSocketHandler;
}, manifest?: GameBackendManifest): GameBackendDefinition;