export type TurnStatus = 'processing' | 'completed' | 'superseded';
export interface LedgerTurn {
    turnIndex: number;
    userMessageTs: string;
    userMessageText: string;
    statusMessageTs: string | null;
    responseMessageTimestamps: string[];
    executionId: string | null;
    backupPath: string | null;
    status: TurnStatus;
    createdAt: string;
    updatedAt: string;
}
export interface ChannelConversation {
    sessionId: string | null;
    sessionName: string | null;
    backend: string;
    /** Profile name used when the conversation was created or switched — needed
     *  by !new / pre-close hooks to resume the session with the same profile. */
    profileName: string | null;
    turns: LedgerTurn[];
    updatedAt: string;
}
export type LedgerData = Record<string, ChannelConversation>;
export declare class ConversationLedgerRepo {
    private repo;
    getConversation(channel: string): Promise<ChannelConversation | null>;
    findTurn(channel: string, userMessageTs: string): Promise<{
        conversation: ChannelConversation;
        turn: LedgerTurn;
        turnIndex: number;
    } | null>;
    initConversation(channel: string, opts: {
        sessionId: string | null;
        sessionName: string | null;
        backend: string;
        profileName?: string | null;
    }): Promise<ChannelConversation>;
    updateSessionId(channel: string, sessionId: string): Promise<void>;
    beginTurn(channel: string, opts: {
        userMessageTs: string;
        userMessageText: string;
        statusMessageTs?: string | null;
        backupPath?: string | null;
    }): Promise<LedgerTurn>;
    addResponseTs(channel: string, userMessageTs: string, responseTs: string): Promise<void>;
    completeTurn(channel: string, userMessageTs: string, opts?: {
        executionId?: string | null;
    }): Promise<void>;
    rollbackTo(channel: string, turnIndex: number): Promise<{
        supersededTurns: LedgerTurn[];
        conversation: ChannelConversation;
    } | null>;
    truncateTurns(channel: string, fromIndex: number): Promise<void>;
    clearConversation(channel: string): Promise<void>;
    switchSession(channel: string, opts: {
        sessionId: string;
        sessionName: string | null;
        backend: string;
        profileName?: string | null;
    }): Promise<void>;
    /**
     * Atomic init-if-missing + beginTurn. Captures the turn index under mutex
     * so callers can safely pass it to sessionBackup.createBackup.
     * Returns { turn, turnIndex } for the caller.
     */
    initAndBeginTurn(channel: string, opts: {
        sessionId: string | null;
        sessionName: string | null;
        backend: string;
        profileName?: string | null;
        userMessageTs: string;
        userMessageText: string;
        statusMessageTs: string;
    }): Promise<{
        turn: LedgerTurn;
        turnIndex: number;
    }>;
    /** Set the backup path on the turn identified by userMessageTs. */
    setBackupPath(channel: string, userMessageTs: string, backupPath: string | null): Promise<void>;
    /** Drop the in-memory cache so the next read() fetches from disk. For testing. */
    invalidate(): void;
    /** Wait for any in-flight mutate() to complete. For graceful SIGTERM drain. */
    flush(): Promise<void>;
}
export declare const conversationLedger: ConversationLedgerRepo;