// SOS-LLM-Provider mit AsyncStorage-Persist + Listener-Pattern.
// Live-Switch im SOS-Screen — analog zu lib/ttsProvider.ts.
//
// Backend (sos-session.post.ts) nimmt das Feld entgegen, sos-stream.get.ts
// routet dann je nach Wert zu OpenRouter (Sonnet/Haiku) oder Groq (Llama).
import AsyncStorage from '@react-native-async-storage/async-storage';
import { useEffect, useState } from 'react';

export type LlmProvider = 'openrouter-sonnet' | 'openrouter-haiku' | 'groq-llama';

const STORAGE_KEY = 'rebreak-sos-llm-provider';
const DEFAULT_PROVIDER: LlmProvider = 'openrouter-sonnet';

export const LLM_PROVIDER_LABEL: Record<LlmProvider, string> = {
  'openrouter-sonnet': 'Sonnet',
  'openrouter-haiku': 'Haiku',
  'groq-llama': 'Groq',
};

const listeners = new Set<(p: LlmProvider) => void>();
let cached: LlmProvider | null = null;

export async function loadLlmProvider(): Promise<LlmProvider> {
  if (cached) return cached;
  const raw = await AsyncStorage.getItem(STORAGE_KEY).catch(() => null);
  cached =
    raw === 'openrouter-haiku' || raw === 'groq-llama' ? raw : DEFAULT_PROVIDER;
  return cached;
}

export async function setLlmProvider(p: LlmProvider): Promise<void> {
  cached = p;
  await AsyncStorage.setItem(STORAGE_KEY, p).catch(() => {});
  for (const cb of listeners) cb(p);
}

/** Always-fresh read — analog zu currentProvider() in ttsProvider.ts. */
export function currentLlmProvider(): LlmProvider {
  return cached ?? DEFAULT_PROVIDER;
}

export function useLlmProvider(): [LlmProvider, (p: LlmProvider) => Promise<void>] {
  const [p, setP] = useState<LlmProvider>(cached ?? DEFAULT_PROVIDER);
  useEffect(() => {
    let mounted = true;
    loadLlmProvider().then((v) => { if (mounted) setP(v); });
    const cb = (v: LlmProvider) => { if (mounted) setP(v); };
    listeners.add(cb);
    return () => { mounted = false; listeners.delete(cb); };
  }, []);
  return [p, setLlmProvider];
}