export type PluginUpdateSourceGroup = 'registryLatest' | 'registryMetadata' | 'updateNotes';
export type PluginUpdateSourceName = 'npm' | 'npmmirror' | 'jsdelivr';
export interface PluginUpdateSourceMetric {
    samples: number;
    averageMs: number;
    successRate: number;
    consecutiveFailures: number;
    lastTestedAt: string;
}
export interface PluginUpdateSourceStats {
    version: 1;
    packageName: string;
    updatedAt: string;
    groups: Record<PluginUpdateSourceGroup, Partial<Record<PluginUpdateSourceName, PluginUpdateSourceMetric>>>;
}
export declare const pluginUpdateSourceCandidates: Record<PluginUpdateSourceGroup, PluginUpdateSourceName[]>;
export declare function createPluginUpdateSourceStats(packageName: string): PluginUpdateSourceStats;
export declare function parsePluginUpdateSourceStats(value: unknown, packageName: string): PluginUpdateSourceStats;
export declare function recordPluginUpdateSourceResult(stats: PluginUpdateSourceStats, group: PluginUpdateSourceGroup, source: PluginUpdateSourceName, success: boolean, durationMs: number, now?: number): void;
export declare function getPluginUpdateSourceOrder(stats: PluginUpdateSourceStats, group: PluginUpdateSourceGroup): PluginUpdateSourceName[];
export declare function shouldCalibratePluginUpdateSource(stats: PluginUpdateSourceStats, group: PluginUpdateSourceGroup, source: PluginUpdateSourceName, now?: number): boolean;