"use client";

/**
 * The provider-voice preference: which TTS provider and voice the listener
 * picked for the podcast player ("system" keeps the platform's own voices).
 * One blob in localStorage, read through a tiny accessor.
 */

import { PROVIDERS, TTS_PROFILES, ttsProfile, type ProviderInfo } from "./providers";

const STORAGE_KEY = "freezmo.podcast-natural.v1";

export type NaturalPref = {
  source: "system" | "natural";
  provider: string;
  voice: string | null;
  model: string | null;
};

const FALLBACK: NaturalPref = { source: "system", provider: "", voice: null, model: null };

export function readNaturalPref(): NaturalPref {
  if (typeof window === "undefined") return FALLBACK;
  try {
    const raw = window.localStorage.getItem(STORAGE_KEY);
    if (!raw) return FALLBACK;
    const parsed = JSON.parse(raw) as Partial<NaturalPref> | null;
    if (!parsed || typeof parsed !== "object") return FALLBACK;
    return {
      source: parsed.source === "natural" ? "natural" : "system",
      provider: typeof parsed.provider === "string" ? parsed.provider : "",
      voice: typeof parsed.voice === "string" ? parsed.voice : null,
      model: typeof parsed.model === "string" ? parsed.model : null,
    };
  } catch {
    return FALLBACK;
  }
}

export function writeNaturalPref(next: Partial<NaturalPref>): NaturalPref {
  const merged = { ...readNaturalPref(), ...next };
  try {
    window.localStorage.setItem(STORAGE_KEY, JSON.stringify(merged));
  } catch {
    /* private mode */
  }
  return merged;
}

/** Providers with a TTS profile that the listener actually has a key for. */
export function ttsProvidersWithKeys(keys: Record<string, string | undefined>): string[] {
  return Object.keys(TTS_PROFILES).filter((id) => Boolean(keys[id]));
}

/** The provider to use when the listener has not chosen one. */
export function defaultTtsProvider(keys: Record<string, string | undefined>, generation?: string): string {
  const available = ttsProvidersWithKeys(keys);
  if (available.length === 0) return "";
  if (generation && available.includes(generation)) return generation;
  /* Prefer OpenAI when both are configured: its voices are the better ones. */
  if (available.includes("openai")) return "openai";
  return available[0];
}

export function voiceForProvider(providerId: string, wanted: string | null): string {
  const profile = ttsProfile(providerId);
  if (!profile) return "";
  if (wanted && profile.voices.some((voice) => voice.id === wanted)) return wanted;
  return profile.voices.find((voice) => voice.male)?.id ?? profile.voices[0]?.id ?? "";
}

/** Provider labels for the picker (id → label). */
export function ttsProviderLabel(id: string): string {
  return PROVIDERS.find((provider: ProviderInfo) => provider.id === id)?.label ?? id;
}

export { TTS_PROFILES };