/**
 * Sherpa TTS Service - STUB for Expo Go development
 * The real implementation requires native modules which don't work in Expo Go
 * This stub returns "not available" so the app falls back to expo-speech
 */

// Available Piper neural voices - kept for type compatibility
export interface PiperVoice {
  id: string;
  name: string;
  description: string;
  modelDir: string;
  onnxFile: string;
  gender: 'male' | 'female';
  accent: string;
}

export const AVAILABLE_VOICES: PiperVoice[] = [
  {
    id: 'lessac',
    name: 'Lessac',
    description: 'American Female (Natural)',
    modelDir: 'vits-piper-en_US-lessac-medium',
    onnxFile: 'en_US-lessac-medium.onnx',
    gender: 'female',
    accent: 'US',
  },
];

interface SherpaTTSState {
  initialized: boolean;
  initializing: boolean;
  error: string | null;
}

let currentState: SherpaTTSState = {
  initialized: false,
  initializing: false,
  error: 'Sherpa TTS disabled for Expo Go development',
};

// State listeners
const stateListeners: ((state: SherpaTTSState) => void)[] = [];

function notifyListeners() {
  stateListeners.forEach(listener => listener({ ...currentState }));
}

export function addStateListener(listener: (state: SherpaTTSState) => void) {
  stateListeners.push(listener);
  listener({ ...currentState });
  return () => {
    const index = stateListeners.indexOf(listener);
    if (index >= 0) stateListeners.splice(index, 1);
  };
}

export function getState(): SherpaTTSState {
  return { ...currentState };
}

// Stub implementations - always return false/unavailable
export async function initializeSherpaTTS(): Promise<boolean> {
  console.log('[SherpaTTS STUB] Sherpa TTS disabled for Expo Go - using expo-speech instead');
  return false;
}

export async function speak(
  text: string,
  options?: {
    speed?: number;
    speakerId?: number;
    onStart?: () => void;
    onDone?: () => void;
    onError?: (error: Error) => void;
  }
): Promise<void> {
  options?.onError?.(new Error('Sherpa TTS disabled for Expo Go'));
}

export function stop(): void {
  // No-op
}

export function deinitialize(): void {
  // No-op
}

export function isAvailable(): boolean {
  return false;
}

export function getCurrentVoice(): PiperVoice {
  return AVAILABLE_VOICES[0];
}

export async function setVoice(voiceId: string): Promise<boolean> {
  return false;
}

export async function loadSavedVoice(): Promise<PiperVoice> {
  return AVAILABLE_VOICES[0];
}

export default {
  initialize: initializeSherpaTTS,
  speak,
  stop,
  deinitialize,
  isAvailable,
  addStateListener,
  getState,
  getVoices: () => AVAILABLE_VOICES,
  getCurrentVoice,
  setVoice,
  loadSavedVoice,
};