import type { TtsLocalModelKey } from "./models.js";
export type TtsProgressStatus = "initiate" | "download" | "progress" | "progress_total" | "done" | "ready" | "error";
export interface TtsProgressFileState {
    loaded: number;
    total: number;
}
export interface TtsProgressEvent {
    modelKey: TtsLocalModelKey;
    status: TtsProgressStatus;
    name?: string;
    file?: string;
    progress?: number;
    loaded?: number;
    total?: number;
    files?: Record<string, TtsProgressFileState>;
    task?: string;
    model?: string;
}
export type TtsWorkerInbound = {
    type: "ping";
    id: string;
} | {
    type: "synthesize";
    id: string;
    modelKey: TtsLocalModelKey;
    text: string;
    voice?: string;
    speed?: number;
} | {
    type: "download";
    id: string;
    modelKey: TtsLocalModelKey;
} | {
    type: "stream-start";
    id: string;
    modelKey: TtsLocalModelKey;
    voice?: string;
    speed?: number;
} | {
    type: "stream-push";
    id: string;
    text: string;
} | {
    type: "stream-end";
    id: string;
} | {
    type: "stream-cancel";
    id: string;
};
export type TtsWorkerOutbound = {
    type: "pong";
    id: string;
} | {
    type: "audio";
    id: string;
    pcm: Float32Array;
    sampleRate: number;
} | {
    type: "downloaded";
    id: string;
} | {
    type: "error";
    id: string;
    error: string;
} | {
    type: "progress";
    id: string;
    event: TtsProgressEvent;
} | {
    type: "log";
    level: "debug" | "warn" | "error";
    msg: string;
    meta?: Record<string, unknown>;
} | {
    type: "audio-chunk";
    id: string;
    index: number;
    text: string;
    pcm: Float32Array;
    sampleRate: number;
} | {
    type: "stream-done";
    id: string;
};
/**
 * Wire transport between the parent (`TtsClient`) and the local TTS subprocess.
 * The parent owns the subprocess lifecycle (graceful work, hard SIGKILL on
 * shutdown); the protocol carries no explicit close handshake — once the parent
 * decides to terminate, it signals the OS to reap the child so
 * `onnxruntime-node`'s NAPI finalizer never runs in the main agent address
 * space (it segfaults Bun on shutdown — issue #1606). See `tts-client.ts` for
 * the spawn/kill glue.
 */
export interface TtsTransport {
    send(message: TtsWorkerOutbound): void;
    /**
     * Send and resolve once the message has drained into the IPC channel.
     * Streaming synthesis awaits this per audio chunk: ONNX inference blocks
     * the worker's event loop for seconds at a time, so fire-and-forget sends
     * queue unflushed until the session ends and arrive as one burst.
     */
    sendAndFlush(message: TtsWorkerOutbound): Promise<void>;
    onMessage(handler: (message: TtsWorkerInbound) => void): () => void;
}