import type { VoiceInfo } from "@rakazo/contracts";

/** Friendly German presets when Kokoro exposes df_/dm_ voices. */
export const GERMAN_VOICE_PRESETS: VoiceInfo[] = [
  { id: "df_eva", label: "Eva", description: "Deutsch · warm" },
  { id: "dm_bernd", label: "Bernd", description: "Deutsch · klar" },
  { id: "df_victoria", label: "Victoria", description: "Deutsch · freundlich" },
  { id: "dm_martin", label: "Martin", description: "Deutsch · ruhig" },
];

const PRESET_BY_ID = new Map(GERMAN_VOICE_PRESETS.map((voice) => [voice.id, voice]));

/** Strip engine prefix (df_eva → Eva) for display when no preset exists. */
export function formatVoiceLabel(id: string): string {
  const preset = PRESET_BY_ID.get(id);
  if (preset) return preset.label;
  const suffix = id.replace(/^[a-z]{2}_/, "");
  if (!suffix) return id;
  return suffix.charAt(0).toUpperCase() + suffix.slice(1).replace(/_/g, " ");
}

export function voiceDescription(id: string, fallback?: string): string | undefined {
  return PRESET_BY_ID.get(id)?.description ?? fallback;
}

/** Prefer German voices when UI locale is de. */
export function preferVoicesForLocale(voices: VoiceInfo[], locale: string): VoiceInfo[] {
  if (locale !== "de") return voices;
  const german = voices.filter((voice) => /^d[fm]_/.test(voice.id));
  if (german.length === 0) return voices;
  const rest = voices.filter((voice) => !/^d[fm]_/.test(voice.id));
  return [...german, ...rest];
}

export function defaultVoiceForLocale(voices: VoiceInfo[], locale: string): VoiceInfo | undefined {
  const ordered = preferVoicesForLocale(voices, locale);
  if (locale === "de") {
    return ordered.find((voice) => voice.id === "df_eva") ?? ordered[0];
  }
  return ordered[0];
}

/** Match a user-provided name (Eva, bernd, df_eva) against available voices. */
export function matchVoiceByName(voices: VoiceInfo[], query: string): VoiceInfo | undefined {
  const needle = query.trim().toLowerCase();
  if (!needle) return undefined;
  const byId = voices.find((voice) => voice.id.toLowerCase() === needle);
  if (byId) return byId;
  const byLabel = voices.find((voice) => voice.label.toLowerCase() === needle);
  if (byLabel) return byLabel;
  const suffix = needle.replace(/^[a-z]{2}_/, "");
  return voices.find((voice) => {
    const label = voice.label.toLowerCase();
    const idSuffix = voice.id.replace(/^[a-z]{2}_/, "").toLowerCase();
    return label.includes(suffix) || idSuffix.includes(suffix) || suffix.includes(idSuffix);
  });
}