/**
 * TalkerStore
 *
 * Structural interface for session/message/status persistence - the
 * write-side counterpart to `ContextStore` (`src/core/context.ts`). Async,
 * matching the I/O it wraps, unlike `ContextStore`'s synchronous contract.
 *
 * `createLibsqlTalkerStore` (`./libsql-store.ts`) is the default
 * implementation, backed by Turso/libSQL. A host can inject another one via
 * `TalkerConfig.store` - to persist through a different database, add
 * instrumentation, or use a fake in tests. `createNullTalkerStore` is what
 * every mount falls back to when neither `store` nor `database` is
 * configured: every write resolves `false` without I/O, matching the
 * historical no-op-when-unconfigured behavior.
 */
import type { Channel, MessagingChannel } from "../types";
export interface SessionRecord {
    id: string;
    phoneNumber: string;
    channel: Channel;
    reason: "ended" | "redirected";
    language: string;
    startedAt: number;
    endedAt: number;
    durationMs: number;
    transferReason?: string;
    conversationId?: string;
}
export interface MessageRecord {
    id: string;
    sessionId: string;
    role: "user" | "assistant";
    content: string;
    timestamp: number;
}
/** Message delivery status record (from Twilio status callbacks) */
export interface MessageStatusRecord {
    messageSid: string;
    channel: MessagingChannel;
    from: string;
    to: string;
    status: string;
    errorCode?: string;
    errorMessage?: string;
}
export interface TalkerStore {
    upsertSession(session: SessionRecord): Promise<boolean>;
    insertMessage(message: MessageRecord): Promise<boolean>;
    upsertMessageStatus(record: MessageStatusRecord): Promise<boolean>;
}
/** Every write resolves `false` without I/O. Default when nothing is configured. */
export declare function createNullTalkerStore(): TalkerStore;
export declare function generateId(): string;
/**
 * Strips formatting (+, spaces, dashes) so the same caller always produces
 * the same session id regardless of how Twilio punctuated the number this
 * time. Digits-only, not a privacy measure - the number is stored as
 * plaintext in `talker_sessions.phone_number` by design; log redaction is a
 * separate concern handled in ../core/logger.ts.
 */
export declare function generateSessionId(phoneNumber: string, startTime: number): string;