import 'dart:io';

import 'package:drift/drift.dart';
import 'package:drift/native.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:melo/library/database.dart';
import 'package:melo/library/scan_service.dart';
import 'package:path/path.dart' as p;

void main() {
  final fixtures = p.join(Directory.current.path, 'test', 'fixtures', 'audio');
  late MeloDb db;
  late Directory coverDir;

  setUp(() async {
    db = MeloDb(NativeDatabase.memory());
    coverDir = await Directory.systemTemp.createTemp('melo_covers');
  });
  tearDown(() async {
    await db.close();
    await coverDir.delete(recursive: true);
  });

  test('scanFolders liest Tags aus den Test-mp3s', () async {
    final count = await scanFolders(db, [fixtures], coverDir: coverDir);
    expect(count, 3);
    final songs = await db.watchSongs().first;
    expect(
      songs.map((s) => s.title).toSet(),
      {'Nachtpuls', 'Taglicht', 'Herzschlag'},
    );
    final nacht = songs.firstWhere((s) => s.title == 'Nachtpuls');
    expect(nacht.artist, 'Rotklang');
    expect(nacht.album, 'Schwarz');
    expect(nacht.durationMs, greaterThan(0));
  });

  test('extrahiert eingebettetes Cover als Datei', () async {
    await scanFolders(db, [fixtures], coverDir: coverDir);
    final songs = await db.watchSongs().first;
    final withCover = songs.where((s) => s.coverPath != null).toList();
    // Nur "Nachtpuls" hat ein eingebettetes Cover.
    expect(withCover.length, 1);
    expect(withCover.first.title, 'Nachtpuls');
    expect(File(withCover.first.coverPath!).existsSync(), isTrue);
  });

  test('Re-Scan behält die UUID (sync-stabil)', () async {
    await scanFolders(db, [fixtures], coverDir: coverDir);
    final firstIds = {
      for (final s in await db.watchSongs().first) s.path: s.id
    };
    await scanFolders(db, [fixtures], coverDir: coverDir);
    final secondIds = {
      for (final s in await db.watchSongs().first) s.path: s.id
    };
    expect(secondIds, firstIds);
    expect((await db.watchSongs().first).length, 3); // keine Duplikate
  });

  test('CRITICAL-1: leerer Scan loescht nicht (nonexistent folder)', () async {
    // Initialer Scan
    await scanFolders(db, [fixtures], coverDir: coverDir);
    final initialCount = (await db.watchSongs().first).length;
    expect(initialCount, 3);

    // Scan mit nicht-existierendem Ordner (livePaths wird leer)
    await scanFolders(db, ['/this/does/not/exist'], coverDir: coverDir);

    // Alle Songs sollten noch da sein
    final afterEmpty = await db.watchSongs().first;
    expect(afterEmpty.length, initialCount);
  });

  test('CRITICAL-2: Datei wird nach Tombstone wieder sichtbar', () async {
    // Initialer Scan: alle 3 Dateien
    await scanFolders(db, [fixtures], coverDir: coverDir);
    var songs = await db.watchSongs().first;
    expect(songs.length, 3);
    final nachtpulsId = songs.firstWhere((s) => s.title == 'Nachtpuls').id;

    // Manuell tombstonen
    await db.upsertSongs([
      SongsCompanion.insert(
        id: nachtpulsId,
        path: p.join(fixtures, '01 Nachtpuls.mp3'),
        title: 'Nachtpuls',
        dateAddedMs: 1,
        updatedAtMs: 1,
        deleted: const Value(true),
      ),
    ]);
    songs = await db.watchSongs().first;
    expect(songs.where((s) => s.title == 'Nachtpuls').length, 0); // nicht sichtbar

    // Re-Scan sollte die Datei wieder finden und deleted=false setzen
    await scanFolders(db, [fixtures], coverDir: coverDir);
    songs = await db.watchSongs().first;
    expect(songs.where((s) => s.title == 'Nachtpuls').length, 1); // wieder da
    expect(songs.length, 3); // alle 3 Songs
  });
}