/**
 * Asset management for ECSpresso ECS framework
 */
import type EventBus from './event-bus';
import type { AssetStatus, AssetDefinition, AssetHandle, AssetsResource, AssetEvents, AssetConfigurator } from './asset-types';
/**
 * Manages asset loading and access for ECSpresso
 */
export default class AssetManager<AssetTypes extends Record<string, unknown> = Record<string, never>, AssetGroupNames extends string = string> {
    private readonly assets;
    private readonly groups;
    private eventBus;
    /**
     * Set the event bus for asset events
     * @internal
     */
    setEventBus(eventBus: EventBus<AssetEvents<keyof AssetTypes & string, AssetGroupNames>>): void;
    /**
     * Register an asset definition
     */
    register<K extends string, T>(key: K, definition: AssetDefinition<T>): void;
    /**
     * Load all assets marked as eager
     */
    loadEagerAssets(): Promise<void>;
    /**
     * Load a single asset by key
     */
    loadAsset<K extends keyof AssetTypes>(key: K): Promise<AssetTypes[K]>;
    /**
     * Load all assets in a group
     */
    loadAssetGroup(groupName: AssetGroupNames): Promise<void>;
    /**
     * Get a loaded asset. Throws if not loaded.
     */
    get<K extends keyof AssetTypes>(key: K): AssetTypes[K];
    /**
     * Get a loaded asset or undefined
     */
    tryGet<K extends keyof AssetTypes>(key: K): AssetTypes[K] | undefined;
    /**
     * Get a handle to an asset with status information
     */
    getHandle<K extends keyof AssetTypes>(key: K): AssetHandle<AssetTypes[K]>;
    /**
     * Get the status of an asset
     */
    getStatus<K extends keyof AssetTypes>(key: K): AssetStatus;
    /**
     * Check if an asset is loaded
     */
    isLoaded<K extends keyof AssetTypes>(key: K): boolean;
    /**
     * Check if all assets in a group are loaded
     */
    isGroupLoaded(groupName: AssetGroupNames): boolean;
    /**
     * Get the loading progress of a group (0-1)
     */
    getGroupProgress(groupName: AssetGroupNames): number;
    /**
     * Get detailed group progress
     */
    getGroupProgressDetails(groupName: AssetGroupNames): {
        loaded: number;
        total: number;
        progress: number;
    };
    /**
     * Check group progress and emit events
     */
    private checkGroupProgress;
    /**
     * Create the $assets resource object
     */
    createResource(): AssetsResource<AssetTypes, AssetGroupNames>;
    /**
     * Get all registered asset keys
     */
    getKeys(): Array<keyof AssetTypes>;
    /**
     * Get all group names
     */
    getGroupNames(): string[];
    /**
     * Get all asset keys in a group
     */
    getGroupKeys(groupName: string): Array<keyof AssetTypes>;
}
/**
 * Implementation of AssetConfigurator for builder pattern
 */
export declare class AssetConfiguratorImpl<Assets extends Record<string, unknown> = {}, AssetGroups extends string = never> implements AssetConfigurator<Assets, AssetGroups> {
    private readonly manager;
    constructor(manager: AssetManager<Assets, AssetGroups>);
    add<K extends string, T>(key: K, loader: () => Promise<T>): AssetConfigurator<Assets & Record<K, T>, AssetGroups>;
    addWithConfig<K extends string, T>(key: K, definition: AssetDefinition<T>): AssetConfigurator<Assets & Record<K, T>, AssetGroups>;
    addGroup<GN extends string, T extends Record<string, () => Promise<unknown>>>(groupName: GN, assets: T): AssetConfigurator<Assets & {
        [K in keyof T]: Awaited<ReturnType<T[K]>>;
    }, AssetGroups | GN>;
    /**
     * Get the underlying manager
     * @internal
     */
    getManager(): AssetManager<Assets, AssetGroups>;
}
/**
 * Create a new AssetConfigurator for builder pattern usage
 */
export declare function createAssetConfigurator<Assets extends Record<string, unknown> = {}, AssetGroups extends string = never>(manager?: AssetManager<Assets, AssetGroups>): AssetConfiguratorImpl<Assets, AssetGroups>;