/// 同声翻译选哪条讯飞微软会话。
///
/// 两端都在同传表里：一条 AST，发音人用短名。
/// 源或目标是中文、粤语、爱尔兰语：不启 AST，识别走微软实时转写，合成用区域码音色。
/// 两边都不在这两类里：不启动。
class SimulRoute {
  const SimulRoute.ast({
    required this.lang,
    required this.targetLang,
    required this.speaker,
  })  : ast = true,
        languageName = '';

  const SimulRoute.splice({
    required this.languageName,
    required this.speaker,
  })  : ast = false,
        lang = '',
        targetLang = '';

  final bool ast;
  /// AST 的源语种短码，例如 ja。
  final String lang;
  /// AST 的目标语种短码，例如 en。
  final String targetLang;
  /// AST 用短名（JennyNeural）。拼接用区域码音色（en-US-JennyNeural）。
  final String speaker;
  /// 拼接识别的 language_name，例如 zh-CN。
  final String languageName;
}

class SimulMicrosoft {
  static SimulRoute? plan(String source, String target) {
    final from = _norm(source);
    final to = _norm(target);
    if (_ast.containsKey(from) && _ast.containsKey(to)) {
      return SimulRoute.ast(
        lang: from,
        targetLang: to,
        speaker: _ast[to]!.speaker,
      );
    }
    if (_splice.containsKey(from) || _splice.containsKey(to)) {
      final locale = _listenLocale(from);
      final voice = _speakVoice(to);
      if (locale == null || voice == null) return null;
      return SimulRoute.splice(languageName: locale, speaker: voice);
    }
    return null;
  }

  /// 同传能力 ast_msft 没授权时，用同一对语种走微软转写加合成。
  /// 识别用区域码，合成用完整神经音色，不再用 AST 的短名。
  static SimulRoute spliceInstead(SimulRoute route) {
    final locale = _listenLocale(route.lang);
    final voice = _speakVoice(route.targetLang);
    if (locale == null || voice == null) return route;
    return SimulRoute.splice(languageName: locale, speaker: voice);
  }

  /// 界面短码收成表里的键。香港繁体要在「凡是 zh- 都当普通话」之前认出来。
  static String _norm(String code) {
    final raw = code.trim().toLowerCase().replaceAll('_', '-');
    if (raw == 'yue' || raw.startsWith('yue-')) return 'yue';
    if (raw == 'ga' || raw.startsWith('ga-')) return 'ga';
    if (raw == 'zh-hant-hk' || raw == 'zh-hk') return 'zh-HK';
    if (raw == 'zh-hant' || raw == 'zh-tw' || raw.startsWith('zh-hant')) {
      return 'zh-Hant';
    }
    if (raw == 'zh' || raw.startsWith('zh-')) return 'zh';
    final dash = raw.indexOf('-');
    return dash < 0 ? raw : raw.substring(0, dash);
  }

  /// 讯飞 SDK 文本翻译（gtrans）的语种码。中文用 zh-CN，不要收成 zh。
  static String translateCode(String code) {
    switch (_norm(code)) {
      case 'zh':
        return 'zh-CN';
      case 'zh-Hant':
        return 'zh-TW';
      case 'zh-HK':
        return 'zh-HK';
      case 'yue':
        return 'yue';
      case 'ga':
        return 'ga';
      default:
        return _norm(code);
    }
  }

  static String? _listenLocale(String key) {
    final splice = _splice[key];
    if (splice != null) return splice.locale;
    return _ast[key]?.locale;
  }

  static String? _speakVoice(String key) {
    final splice = _splice[key];
    if (splice != null) return splice.voice;
    final ast = _ast[key];
    if (ast == null) return null;
    return '${ast.locale}-${ast.speaker}';
  }

  /// 同传表。speaker 是 AST 的短名，locale 是拼接到 OnlineTTS 时用的区域码。
  static const _ast = <String, _AstLang>{
    'ar': _AstLang('ar-EG', 'AbdullahNeural'),
    'bg': _AstLang('bg-BG', 'BorislavNeural'),
    'bn': _AstLang('bn-IN', 'BashkarNeural'),
    'ca': _AstLang('ca-ES', 'AlbaNeural'),
    'cs': _AstLang('cs-CZ', 'AntoninNeural'),
    'da': _AstLang('da-DK', 'ChristelNeural'),
    'de': _AstLang('de-DE', 'AmalaNeural'),
    'el': _AstLang('el-GR', 'AthinaNeural'),
    'en': _AstLang('en-US', 'JennyNeural'),
    'es': _AstLang('es-ES', 'ElviraNeural'),
    'et': _AstLang('et-EE', 'AnuNeural'),
    'fa': _AstLang('fa-IR', 'DilaraNeural'),
    'fi': _AstLang('fi-FI', 'HarriNeural'),
    'fr': _AstLang('fr-FR', 'DeniseNeural'),
    'hi': _AstLang('hi-IN', 'MadhurNeural'),
    'hu': _AstLang('hu-HU', 'NoemiNeural'),
    'id': _AstLang('id-ID', 'ArdiNeural'),
    'it': _AstLang('it-IT', 'ElsaNeural'),
    'ja': _AstLang('ja-JP', 'NanamiNeural'),
    'ko': _AstLang('ko-KR', 'SunHiNeural'),
    'lt': _AstLang('lt-LT', 'LeonasNeural'),
    'lv': _AstLang('lv-LV', 'EveritaNeural'),
    'ms': _AstLang('ms-MY', 'OsmanNeural'),
    'nl': _AstLang('nl-NL', 'ArnaudNeural'),
    'pl': _AstLang('pl-PL', 'AgnieszkaNeural'),
    'pt': _AstLang('pt-BR', 'AntonioNeural'),
    'ro': _AstLang('ro-RO', 'AlinaNeural'),
    'ru': _AstLang('ru-RU', 'DariyaNeural'),
    'sk': _AstLang('sk-SK', 'LukasNeural'),
    'sl': _AstLang('sl-SI', 'PetraNeural'),
    'sv': _AstLang('sv-SE', 'HilleviNeural'),
    'sw': _AstLang('sw-KE', 'DaudiNeural'),
    'ta': _AstLang('ta-IN', 'AnbuNeural'),
    'th': _AstLang('th-TH', 'AcharaNeural'),
    'tr': _AstLang('tr-TR', 'AhmetNeural'),
    'uk': _AstLang('uk-UA', 'OstapNeural'),
    'ur': _AstLang('ur-IN', 'AsadNeural'),
    'vi': _AstLang('vi-VN', 'HoaiMyNeural'),
  };

  /// 微软同传表没有的三语。繁体中文按普通话识别，合成用繁体音色。
  static const _splice = <String, _SpliceLang>{
    'zh': _SpliceLang('zh-CN', 'zh-CN-XiaoxiaoNeural'),
    'zh-Hant': _SpliceLang('zh-CN', 'zh-TW-HsiaoChenNeural'),
    'yue': _SpliceLang('yue-CN', 'yue-CN-XiaoMinNeural'),
    'zh-HK': _SpliceLang('zh-HK', 'zh-HK-HiuMaanNeural'),
    'ga': _SpliceLang('ga-IE', 'ga-IE-OrlaNeural'),
  };
}

class _AstLang {
  const _AstLang(this.locale, this.speaker);
  final String locale;
  final String speaker;
}

class _SpliceLang {
  const _SpliceLang(this.locale, this.voice);
  final String locale;
  final String voice;
}