import { GameEventBus } from "../classes/eventBus.d.ts";
/**
 * A generic finite state machine with optional guard functions, lifecycle callbacks, and event bus integration.
 *
 * @template States - A string union of valid state names.
 */
export declare class StateMachine<States extends string> {
    private _currentState;
    private readonly transitions;
    private readonly wildcardTransitions;
    private readonly enterCallbacks;
    private readonly exitCallbacks;
    private readonly eventBus?;
    constructor(initialState: States, eventBus?: GameEventBus<Record<string, unknown>>);
    get currentState(): States;
    /**
     * Register a valid transition from one state to another, with an optional guard function.
     */
    addTransition(from: States, to: States, guard?: () => boolean): void;
    /**
     * Register a wildcard transition: allows transitioning to the given state from any state.
     */
    addTransitionFromAny(to: States, guard?: () => boolean): void;
    /**
     * Register a callback to run when entering a state.
     */
    onEnter(state: States, callback: () => void): void;
    /**
     * Register a callback to run when exiting a state.
     */
    onExit(state: States, callback: () => void): void;
    /**
     * Check if a transition to the given state is defined (ignoring guards).
     */
    canTransition(to: States): boolean;
    /**
     * Execute a transition to the target state.
     * Flow: validate -> run guard -> call exit callbacks -> change state -> call enter callbacks.
     *
     * @throws If no transition is defined from the current state to the target, or if a guard rejects.
     */
    transition(to: States): void;
}