/**
 * Text-to-speech playback for the widget.
 *
 * ## What this replaced
 *
 * The previous controller drove a `MediaSource` + `SourceBuffer` pipeline fed by
 * `tts_start` / `tts_data` / `tts_end` SSE frames. TORUK-CORE has never emitted
 * those events. On-demand speech therefore read a stream that produced nothing:
 * no audio, no error, no way for a user to tell it had failed. Around 250 lines
 * of chunk-queue and buffer-teardown machinery existed to serve a protocol with
 * no server on the other end.
 *
 * CORE's actual contract is buffered, and there are two ways in:
 *
 *  - **On demand** — `POST :deploymentId/tts` answers with one JSON envelope
 *    carrying `{ data, contentType }`, where `data` is base64 for the whole clip.
 *  - **Automatic** — when the flow has auto-TTS on, CORE pushes the same object
 *    as a single `ttsAudio` SSE frame during the turn, and persists it on the
 *    message so it comes back with history.
 *
 * Both are handled here, and both end up on one `<audio>` element.
 *
 * ## One utterance at a time
 *
 * A single element is reused for every message rather than one per message.
 * `packages/ui` mounts an element per bubble with no arbitration, so pressing
 * speak on a second message plays both at once; that is deliberately not copied.
 * Starting any playback stops whatever was playing, and `stopAll()` is called on
 * a new response, a session switch, and unmount.
 *
 * `loading` and `playing` are tracked separately: the gap between them is a
 * network round trip, and collapsing the two leaves the button showing "playing"
 * while nothing is audible.
 */
import { Accessor } from 'solid-js';
import type { MessageType } from '@/widget/types';
import type { TtsAudioPayload } from '@/streaming/sse-events';
type TTSConfig = {
    apiHost: string | undefined;
    deploymentId: string;
    chatId: Accessor<string>;
    messages: Accessor<MessageType[]>;
    setMessages: (fn: (prev: MessageType[]) => MessageType[]) => void;
    onRequest?: (request: RequestInit) => Promise<void>;
};
/** Why speech is unavailable, kept as state so the UI can show it rather than throw. */
export type TtsError = {
    /** `NOT_CONFIGURED` — the deployment has no TTS connection; hide the control. */
    code: 'NOT_CONFIGURED' | 'SYNTHESIS_FAILED' | 'PLAYBACK_FAILED';
    message: string;
};
/** Render a CORE payload as something an `<audio>` element can load. */
export declare function toAudioDataUri(payload: TtsAudioPayload): string;
export declare function createTTSController(config: TTSConfig): {
    isTTSEnabled: Accessor<boolean>;
    setIsTTSEnabled: import("solid-js").Setter<boolean>;
    isTTSLoading: Accessor<Record<string, boolean>>;
    isTTSPlaying: Accessor<Record<string, boolean>>;
    isTTSActive: () => boolean;
    ttsError: Accessor<TtsError | undefined>;
    handleTTSClick: (messageId: string, messageText: string) => Promise<void>;
    handleTTSStop: (messageId: string) => void;
    /** Attach without playing — history hydration and on-demand caching. */
    attachTtsAudio: (messageId: string, payload: TtsAudioPayload) => void;
    /** Attach and speak — CORE's `ttsAudio` SSE frame for the turn in flight. */
    playLiveTtsAudio: (messageId: string, payload: TtsAudioPayload) => Promise<void>;
    stopAllTTS: () => void;
};
export {};