// lib/metadata/metadata_model.dart
import 'dart:typed_data';

/// 从音频文件读取的原始元数据（未经任何处理）
class RawMetadata {
  final String title;
  final String artist;
  final String album;
  final String albumArtist;
  final String composer;
  final String genre;
  final int year;
  final int trackNumber;
  final int discNumber;
  final Uint8List? artwork;

  const RawMetadata({
    this.title = '',
    this.artist = '',
    this.album = '',
    this.albumArtist = '',
    this.composer = '',
    this.genre = '',
    this.year = 0,
    this.trackNumber = 0,
    this.discNumber = 0,
    this.artwork,
  });

  /// 判断是否为空（没有任何有效信息）
  bool get isEmpty =>
      title.isEmpty &&
      artist.isEmpty &&
      album.isEmpty &&
      albumArtist.isEmpty &&
      composer.isEmpty &&
      genre.isEmpty &&
      year == 0 &&
      trackNumber == 0 &&
      discNumber == 0 &&
      artwork == null;

  bool get isNotEmpty => !isEmpty;
}

/// 经过标准化处理后的元数据
class NormalizedMetadata {
  final String title;
  final String artist;
  final String album;
  final String albumArtist;
  final String composer;
  final String genre;
  final int year;
  final int trackNumber;
  final int discNumber;
  final Uint8List? artwork;

  const NormalizedMetadata({
    this.title = '',
    this.artist = '',
    this.album = '',
    this.albumArtist = '',
    this.composer = '',
    this.genre = '',
    this.year = 0,
    this.trackNumber = 0,
    this.discNumber = 0,
    this.artwork,
  });

  bool get isEmpty =>
      title.isEmpty &&
      artist.isEmpty &&
      album.isEmpty &&
      albumArtist.isEmpty &&
      composer.isEmpty &&
      genre.isEmpty &&
      year == 0 &&
      trackNumber == 0 &&
      discNumber == 0 &&
      artwork == null;

  bool get isNotEmpty => !isEmpty;
}

/// 带置信度的候选元数据
class CandidateMetadata {
  final NormalizedMetadata metadata;
  final double confidence; // 0.0 ~ 1.0
  final Map<String, double> evidence; // 证据来源权重

  const CandidateMetadata({
    required this.metadata,
    required this.confidence,
    this.evidence = const {},
  });
}

/// 最终确认的元数据
class FinalMetadata {
  final String title;
  final String artist;
  final String album;
  final String albumArtist;
  final String composer;
  final String genre;
  final int year;
  final int trackNumber;
  final int discNumber;
  final Uint8List? artwork;
  final String source; // 'file_tag', 'filename', 'cache', 'user_corrected'

  const FinalMetadata({
    this.title = '',
    this.artist = '',
    this.album = '',
    this.albumArtist = '',
    this.composer = '',
    this.genre = '',
    this.year = 0,
    this.trackNumber = 0,
    this.discNumber = 0,
    this.artwork,
    this.source = 'unknown',
  });

  bool get isEmpty =>
      title.isEmpty &&
      artist.isEmpty &&
      album.isEmpty &&
      albumArtist.isEmpty &&
      composer.isEmpty &&
      genre.isEmpty &&
      year == 0 &&
      trackNumber == 0 &&
      discNumber == 0 &&
      artwork == null;

  bool get isNotEmpty => !isEmpty;
}