import type { WatchdogReport, WatchdogRoleStatus } from './report.js';
import type { WatchManifest } from './briefing.js';
/**
 * Severity ordering, lowest to highest (must match the briefing contract's alert-rules
 * sentence verbatim, src/watchdog/briefing.ts): healthy = idle (0) < unknown (1) < stale (2)
 * < blocked = unreachable (3) < off_briefing (4).
 */
export declare const WATCHDOG_STATUS_RANK: Record<WatchdogRoleStatus, number>;
export interface OpenFinding {
    role: string;
    status: WatchdogRoleStatus;
    since: string;
    lastAlertedAt: string | null;
}
export interface AlertLedger {
    version: 1;
    open: Record<string, OpenFinding>;
    heldDownAlerted: boolean;
}
/** Missing or corrupt ledger file yields a clean empty ledger rather than throwing. */
export declare function readLedger(name: string): AlertLedger;
export declare function writeLedger(name: string, l: AlertLedger): void;
/**
 * An `error`-status report carries no role evidence, so the ledger
 * is returned unchanged. For each finding with rank > 0: an existing open entry keeps its
 * `since` and updates `status` on escalation/de-escalation; a new one opens with `since = now`.
 * Any role reported `healthy`/`idle` closes (deletes) its open entry. Every role named in
 * `report.alerts` gets `lastAlertedAt = now`. Roles absent from the report keep their entries —
 * a watchdog with a narrowed `watch:` set doesn't silently resolve findings it never inspected.
 * Never mutates `l` — always returns a new ledger object.
 */
export declare function reconcileLedger(l: AlertLedger, report: WatchdogReport, now: Date): AlertLedger;
/** Ledger open findings and cooldown in the shape carried by watch.json's `digest` field. */
export declare function computeDigest(l: AlertLedger, cooldownMs: number, now: Date): WatchManifest['digest'];