/**
 * EventJournal — append-only per-session event log.
 *
 * Every ProviderRuntimeEvent emitted by a HarnessDriver is appended to
 * <projectRoot>/.memoire/studio/events/<sessionId>.jsonl as a single JSON
 * line with the event's monotonic seq as the index.
 *
 * Unlocks:
 *   - Audit trails: replay every action a session performed
 *   - Offline playback: re-render a finished session without keeping it
 *     warm in memory
 *   - Crash forensics: see exactly the last events before a runtime kill
 *   - Replay-from-cursor: a UI client that lost connection mid-session
 *     can request `replay(sessionId, fromSeq)` and stream the tail
 *
 * Two implementations:
 *   - FileEventJournal — appends JSONL files to disk
 *   - MemoryEventJournal — for tests
 *
 * The journal is injected into HarnessDriverConfig.eventJournal. When
 * absent, drivers behave exactly as before (no journal writes). Like
 * snapshots, the integration is opt-in.
 */
import type { SessionId } from "../contracts/ids.js";
import type { ProviderRuntimeEvent } from "../contracts/provider-runtime.js";
export interface EventJournal {
    append(sessionId: SessionId, event: ProviderRuntimeEvent): Promise<void>;
    /** Returns events for the session in seq order, optionally from a cursor. */
    replay(sessionId: SessionId, fromSeq?: number): AsyncIterable<ProviderRuntimeEvent>;
    /** Returns the list of session IDs with persisted journals. */
    list(): Promise<SessionId[]>;
    /** Removes the journal for a single session. */
    delete(sessionId: SessionId): Promise<void>;
    /** Removes journals matching the prune criteria. Returns the count removed. */
    prune(opts: {
        olderThanMs?: number;
        max?: number;
    }): Promise<number>;
}
/**
 * In-memory implementation. Useful for tests and dry-runs.
 */
export declare class MemoryEventJournal implements EventJournal {
    private readonly buffers;
    private readonly mtimes;
    append(sessionId: SessionId, event: ProviderRuntimeEvent): Promise<void>;
    replay(sessionId: SessionId, fromSeq?: number): AsyncIterable<ProviderRuntimeEvent>;
    list(): Promise<SessionId[]>;
    delete(sessionId: SessionId): Promise<void>;
    prune(opts: {
        olderThanMs?: number;
        max?: number;
    }): Promise<number>;
}
/**
 * Disk-backed implementation. Each session gets its own JSONL file under
 * <projectRoot>/.memoire/studio/events/<sessionId>.jsonl. Appends are
 * serialized per session via an inflight promise chain so out-of-order
 * concurrent writes can't interleave bytes.
 */
export declare class FileEventJournal implements EventJournal {
    private readonly dir;
    private ensureDirPromise;
    private readonly inflight;
    constructor(projectRoot: string);
    private ensureDir;
    private filePath;
    append(sessionId: SessionId, event: ProviderRuntimeEvent): Promise<void>;
    replay(sessionId: SessionId, fromSeq?: number): AsyncIterable<ProviderRuntimeEvent>;
    list(): Promise<SessionId[]>;
    delete(sessionId: SessionId): Promise<void>;
    prune(opts: {
        olderThanMs?: number;
        max?: number;
    }): Promise<number>;
}
/**
 * Helper: collect a journal replay into an array. Convenient for tests.
 */
export declare function collectReplay(journal: EventJournal, sessionId: SessionId, fromSeq?: number): Promise<ProviderRuntimeEvent[]>;