export interface VoiceInfo {
    id: string;
    name: string;
    lang: string;
    /** Locale-aware display label, e.g. "Google US English" */
    label: string;
    /** True when this is the browser/service default voice */
    default: boolean;
}
export interface SpeakOptions {
    /** Text to synthesise */
    text: string;
    /** Override the provider-level default voice */
    voice?: VoiceInfo;
    /** Speech rate 0.1–10 (1 = normal) */
    rate?: number;
    /** Pitch 0–2 (1 = normal). Not supported by AI providers — ignored silently */
    pitch?: number;
    /** Volume 0–1 (1 = full) */
    volume?: number;
}
export type SpeechErrorCode = 'NOT_SUPPORTED' | 'PERMISSION_DENIED' | 'NETWORK' | 'API_ERROR' | 'RATE_LIMIT' | 'AUDIO_PLAYBACK' | 'CANCELLED' | 'UNKNOWN';
export interface SpeechError {
    code: SpeechErrorCode;
    message: string;
    /** Original error for debugging */
    cause?: unknown;
}
export interface TTSProvider {
    /** Whether the TTS API is available in the current environment */
    readonly isSupported: boolean;
    /** Speak the given text. Resolves when the utterance ends naturally */
    speak(options: SpeakOptions): Promise<void>;
    /** Stop any in-progress utterance immediately */
    stop(): void;
    /** Pause the current utterance (Web Speech only; no-op for AI providers) */
    pause(): void;
    /** Resume a paused utterance (Web Speech only; no-op for AI providers) */
    resume(): void;
    /** Return all available voices. May trigger an async fetch for AI providers */
    getVoices(): Promise<VoiceInfo[]>;
    /** Called when an utterance starts playing */
    onStart(cb: () => void): void;
    /** Called when an utterance ends (either naturally or via stop()) */
    onEnd(cb: () => void): void;
    /** Called when an error occurs */
    onError(cb: (err: SpeechError) => void): void;
}
export interface STTProvider {
    /** Whether the STT API is available in the current environment */
    readonly isSupported: boolean;
    /** Whether recognition is configured as continuous */
    readonly continuous: boolean;
    /** Start listening */
    start(): void;
    /** Stop listening */
    stop(): void;
    /** Called on every interim transcript update */
    onTranscript(cb: (transcript: string, confidence: number) => void): void;
    /** Called when the recogniser commits a final result */
    onFinalTranscript(cb: (transcript: string, confidence: number) => void): void;
    /** Called when recognition ends naturally (not via a manual stop() call) */
    onEnd(cb: () => void): void;
    /** Called when a recognition error occurs */
    onError(cb: (err: SpeechError) => void): void;
}
export interface WebSpeechConfig {
    provider: 'web';
    /** BCP-47 lang code used as default for STT, e.g. 'en-US' */
    lang?: string;
}
export interface OpenAIConfig {
    provider: 'openai';
    apiKey: string;
    /** Override the API base URL — useful for proxying keys in production */
    baseURL?: string;
    model?: 'tts-1' | 'tts-1-hd';
    voice?: 'alloy' | 'echo' | 'fable' | 'onyx' | 'nova' | 'shimmer';
    speed?: number;
}
export interface ElevenLabsConfig {
    provider: 'elevenlabs';
    apiKey: string;
    /** Override the API base URL — useful for proxying keys in production */
    baseURL?: string;
    voiceId?: string;
    modelId?: string;
    stability?: number;
    similarityBoost?: number;
}
export interface AzureConfig {
    provider: 'azure';
    subscriptionKey: string;
    region: string;
    /** Override the API base URL — useful for proxying keys in production */
    baseURL?: string;
    voice?: string;
}
export type ProviderConfig = WebSpeechConfig | OpenAIConfig | ElevenLabsConfig | AzureConfig;