/**
 * Disk caching for POC pipeline phases.
 *
 * The local POC pulls live events from a SIEM, runs them through the
 * templater, builds a v2 envelope. Each phase is independently
 * expensive — a 1h CloudWatch pull is 10-30s, a templater run on
 * 100k events is 30-90s. Iterating on envelope shape or downstream
 * enrichment shouldn't re-trigger either.
 *
 * Cache key is the tuple of (siem, scope, window, target_event_count,
 * query). Two phases:
 *
 *   <cache-dir>/<key>/events.jsonl                    — pulled SIEM events
 *   <cache-dir>/<key>/templater/templates.json        — templater output
 *   <cache-dir>/<key>/templater/encoded.log
 *   <cache-dir>/<key>/templater/aggregated.csv
 *
 * Default cache root is /tmp/log10x-poc-cache; override with
 * LOG10X_POC_CACHE_DIR. Caches persist until manually cleared — the
 * caller invalidates by removing the directory or changing any
 * key-contributing arg.
 *
 * Never throws — every read/write degrades to "no cache" on error.
 */
export interface CacheKeyArgs {
    siem: string;
    scope?: string;
    window: string;
    target_event_count: number;
    query?: string;
}
export interface CacheEntry {
    key: string;
    dir: string;
    /** True when the cache dir existed before this call. */
    preExisted: boolean;
    /** Seconds since the dir's mtime (only meaningful when preExisted). */
    ageSeconds: number;
}
/**
 * Stable 16-char hex key over the user-visible cache-contributing
 * args. Excludes auth-style fields (analyzer_cost_per_gb)
 * that don't affect the events or engine output.
 */
export declare function computeCacheKey(args: CacheKeyArgs): string;
export declare function getOrCreateCacheDir(key: string): CacheEntry;
export declare function hasCachedEvents(dir: string): boolean;
export declare function writeCachedEvents(dir: string, events: unknown[]): void;
export declare function readCachedEvents(dir: string): unknown[];
export interface CachedTemplaterOutput {
    templatesJson: string;
    encodedLog: string;
    aggregatedCsv: string;
}
export declare function hasCachedTemplaterOutput(dir: string): boolean;
export declare function readCachedTemplaterOutput(dir: string): CachedTemplaterOutput | null;
export declare function writeCachedTemplaterOutput(dir: string, out: CachedTemplaterOutput): void;
/**
 * Summarize what's cached at a given cache dir for telemetry in the
 * v2 envelope (so the report header can say "events: cache hit (47s
 * old) / templater: cache miss"). Never throws.
 */
export interface CacheStatus {
    key: string;
    dir: string;
    events_cached: boolean;
    events_age_seconds: number | null;
    templater_cached: boolean;
    templater_age_seconds: number | null;
}
export declare function inspectCache(key: string): CacheStatus;