import Signal from "badmfck-signal";
export declare const BLUEGREEN_FILE = ".bluegreen.json";
export type TSlot = "blue" | "green";
export interface IBlueGreenState {
    live: boolean | null;
    bluegreen: boolean;
    project: string | null;
    slot: TSlot | null;
    active: TSlot | null;
    isActive: boolean | null;
    lastDeployed: TSlot | null;
    readyToSwitch: boolean | null;
    checkedAt: number;
    cached: boolean;
    stale?: boolean;
    error?: string;
}
export declare const S_BLUEGREEN_STATE_CHANGED: Signal<{
    current: IBlueGreenState;
    previous: IBlueGreenState | null;
}>;
export interface IBlueGreenStateOptions {
    force?: boolean;
    ttlMs?: number;
    timeoutMs?: number;
}
export declare function onLiveChange(cb: (live: boolean, state: IBlueGreenState) => void): () => void;
export declare function getBlueGreenStateSync(): IBlueGreenState | null;
export declare function startBlueGreenWatcher(intervalMs?: number): void;
export declare function stopBlueGreenWatcher(): void;
export declare function getBlueGreenActiveState(opts?: IBlueGreenStateOptions): Promise<IBlueGreenState>;