import { EventEmitter2 } from '@nestjs/event-emitter';
import { UpdatePhase, UpdateStatusType } from '../system.constants';
export type InstallType = 'image' | 'npm';
export interface VersionInfo {
    current: string;
    latest: string | null;
    updateAvailable: boolean;
    updateType: 'patch' | 'minor' | 'major' | null;
}
export interface ReleaseAsset {
    name: string;
    downloadUrl: string;
    size: number;
}
export interface PanelVersionInfo {
    latest: string | null;
    assets: ReleaseAsset[];
}
export interface UpdateStatusInfo {
    status: UpdateStatusType;
    phase: UpdatePhase | null;
    progressPercent: number | null;
    message: string | null;
    error: string | null;
    startedAt: Date | null;
}
export interface ReleaseNotes {
    version: string;
    body: string | null;
    url: string;
    publishedAt: string | null;
}
export declare class UpdateService {
    private readonly eventEmitter;
    private readonly logger;
    private readonly NPM_REGISTRY_URL;
    private readonly GITHUB_API_URL;
    private readonly GITHUB_VERSION_JSON_URL;
    private readonly GITHUB_PRERELEASE_API_URL;
    private cachedServerInfo;
    private cachedPanelInfo;
    private serverCacheTimestamp;
    private panelCacheTimestamp;
    private cachedReleaseNotes;
    private readonly CACHE_TTL_MS;
    private updateStatus;
    private updateLockAcquiredAt;
    private readonly UPDATE_LOCK_TIMEOUT_MS;
    private static readonly FETCH_TIMEOUT_MS;
    private static readonly IMAGE_BASE_DIR;
    private static readonly IMAGE_CURRENT_LINK;
    private static readonly IMAGE_MARKER_FILE;
    constructor(eventEmitter: EventEmitter2);
    getCurrentVersion(): string;
    getInstallType(): InstallType;
    getInstalledVersions(): string[];
    getImageBaseDir(): string;
    getStatus(): UpdateStatusInfo;
    isUpdateInProgress(): boolean;
    acquireUpdateLock(): boolean;
    releaseUpdateLock(): void;
    setStatus(partial: Partial<UpdateStatusInfo>): void;
    checkServerUpdate(channel?: 'latest' | 'beta' | 'alpha'): Promise<VersionInfo>;
    private fetchLatestVersionFromGitHub;
    private fetchLatestVersionFromNpm;
    fetchReleaseNotes(version: string): Promise<ReleaseNotes>;
    fetchServerReleaseAsset(version: string): Promise<ReleaseAsset | null>;
    private fetchGitHubRelease;
    scheduledUpdateCheck(): Promise<void>;
    invalidateServerCache(): void;
    checkPanelUpdate(prerelease?: boolean): Promise<PanelVersionInfo>;
    fetchPanelRelease(version: string): Promise<PanelVersionInfo>;
    private mapReleaseAssets;
}