import 'version_source_card.dart';


class VersionSourceGroup {
  final List<VersionSourceCardData> members;

  VersionSourceGroup(List<VersionSourceCardData> members)
    : assert(members.isNotEmpty),
      members = List.unmodifiable(members);

  VersionSourceCardData get representative => members.first;

  VersionSourceCardData? get activeMember {
    for (final member in members) {
      if (member.isCurrent || member.selected) return member;
    }
    return null;
  }

  bool get hasActiveMember => activeMember != null;

  bool get hasCurrentMember => members.any((member) => member.isCurrent);

  List<String> get serverNames =>
      List.unmodifiable([for (final member in members) member.serverName]);


  VersionSourceCardData get displayData {
    final visibleMember = activeMember ?? representative;
    final names = serverNames;
    final hasCurrent = hasCurrentMember;
    final hasSelected = !hasCurrent && members.any((member) => member.selected);
    final serverList = names.join('、');

    return VersionSourceCardData(
      topLabel: visibleMember.topLabel,
      sizeBytes: visibleMember.sizeBytes,
      bitrate: visibleMember.bitrate,
      serverName: visibleMember.serverName,
      serverKey: visibleMember.serverKey,
      isCurrent: hasCurrent,
      selected: hasSelected,
      onTap: visibleMember.onTap,
      tooltip: names.length > 1 ? '可用服务器：$serverList' : visibleMember.tooltip,
      resolutionLabel: visibleMember.resolutionLabel,
      sourceKey: visibleMember.sourceKey,
      mergedServerNames: names,
    );
  }
}


String? versionGroupKeyOf({
  required int? sizeBytes,
  required String resolutionLabel,
}) {
  if (sizeBytes == null || sizeBytes <= 0) return null;
  return '$sizeBytes|${resolutionLabel.trim().toUpperCase()}';
}


List<VersionSourceGroup> groupVersionEntries(
  List<VersionSourceCardData> entries,
) {
  final groupedMembers = <String, List<List<VersionSourceCardData>>>{};
  final orderedMemberLists = <List<VersionSourceCardData>>[];

  for (final entry in entries) {
    final groupKey = versionGroupKeyOf(
      sizeBytes: entry.sizeBytes,
      resolutionLabel: entry.resolutionLabel,
    );
    if (groupKey == null) {
      orderedMemberLists.add([entry]);
      continue;
    }

    final candidateGroups = groupedMembers[groupKey] ?? const [];
    List<VersionSourceCardData>? matchingGroup;
    for (final candidateGroup in candidateGroups) {
      final alreadyContainsServer = candidateGroup.any(
        (member) => member.serverKey == entry.serverKey,
      );
      if (!alreadyContainsServer) {
        matchingGroup = candidateGroup;
        break;
      }
    }
    if (matchingGroup != null && entry.serverKey.isNotEmpty) {
      matchingGroup.add(entry);
      continue;
    }

    final newMembers = <VersionSourceCardData>[entry];
    groupedMembers.putIfAbsent(groupKey, () => []).add(newMembers);
    orderedMemberLists.add(newMembers);
  }

  return [
    for (final members in orderedMemberLists) VersionSourceGroup(members),
  ];
}