import 'dart:io';

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../../durum/proje_durumu.dart';
import '../../modeller/segment.dart';
import '../../servisler/analiz/waveform_olusturucu.dart';
import '../../servisler/proje_deposu.dart';

/// Basit dalga formu + segment ribbon (RMS verisi yoksa placeholder).
class WaveformWidget extends ConsumerStatefulWidget {
  const WaveformWidget({super.key});

  @override
  ConsumerState<WaveformWidget> createState() => _WaveformWidgetState();
}

class _WaveformWidgetState extends ConsumerState<WaveformWidget> {
  double _playheadZamani = 0;
  bool _beatSnapAcik = false;

  // Sürükleme durumu
  String? _suruklenenSegmentId;
  bool _suruklenenSolKenar = false;
  double? _suruklenenYeniDeger;

  @override
  Widget build(BuildContext context) {
    final proje = ref.watch(projeProvider);
    final secId = ref.watch(secilenSegmentIdProvider);
    if (proje == null || proje.segmentler.isEmpty) {
      return const SizedBox(height: 100);
    }
    final theme = Theme.of(context);
    final toplamSure = proje.segmentler.last.bit;
    final rmsAkis = proje.analiz.rmsDegerleri;
    if (rmsAkis.isEmpty &&
        proje.kaynak.sesPath.isNotEmpty &&
        File(proje.kaynak.sesPath).existsSync()) {
      _waveformCikartTetikle(ref, proje);
    }

    final beatler = _beatlerHesapla(proje, toplamSure);

    return Container(
      decoration: BoxDecoration(
        color: theme.colorScheme.surfaceContainerHighest,
        borderRadius: BorderRadius.circular(6),
        border: Border.all(color: theme.dividerColor),
      ),
      child: Column(
        children: [
          // Toolbar
          Container(
            height: 24,
            padding: const EdgeInsets.symmetric(horizontal: 8),
            decoration: BoxDecoration(
              color: theme.colorScheme.surface,
              borderRadius:
                  const BorderRadius.vertical(top: Radius.circular(6)),
            ),
            child: Row(
              children: [
                Icon(Icons.straighten,
                    size: 14, color: theme.colorScheme.onSurface),
                const SizedBox(width: 4),
                const Text('Beat-snap', style: TextStyle(fontSize: 11)),
                const SizedBox(width: 4),
                Transform.scale(
                  scale: 0.7,
                  child: Switch(
                    value: _beatSnapAcik,
                    onChanged: beatler.isEmpty
                        ? null
                        : (v) => setState(() => _beatSnapAcik = v),
                  ),
                ),
                const Spacer(),
                Text(
                  '${_playheadZamani.toStringAsFixed(2)}s',
                  style: TextStyle(
                    fontSize: 10,
                    color: theme.colorScheme.onSurfaceVariant,
                  ),
                ),
              ],
            ),
          ),
          // Cetvel (tıklanabilir)
          LayoutBuilder(builder: (ctx, c) {
            return GestureDetector(
              behavior: HitTestBehavior.opaque,
              onTapDown: (d) =>
                  _cetvelTiklandi(d.localPosition, c.maxWidth, toplamSure, proje),
              child: SizedBox(
                height: 16,
                child: CustomPaint(
                  size: const Size.fromHeight(16),
                  painter: _CetvelCizici(
                    toplamSure: toplamSure,
                    renk: theme.colorScheme.outline,
                    playheadX: c.maxWidth > 0
                        ? (_playheadZamani / toplamSure) * c.maxWidth
                        : null,
                  ),
                ),
              ),
            );
          }),
          // Waveform (tıklanabilir + sürüklenebilir playhead)
          LayoutBuilder(builder: (ctx, c) {
            return SizedBox(
              height: 50,
              child: GestureDetector(
                behavior: HitTestBehavior.opaque,
                onTapDown: (d) => _waveformTiklandi(
                    d.localPosition, c.maxWidth, toplamSure, proje),
                onPanUpdate: (d) => _waveformTiklandi(
                    d.localPosition, c.maxWidth, toplamSure, proje),
                child: Stack(
                  children: [
                    Positioned.fill(
                      child: rmsAkis.isNotEmpty
                          ? CustomPaint(
                              painter: _WaveformCizici(
                                rms: rmsAkis,
                                renk: theme.colorScheme.primary,
                              ),
                              child: const SizedBox.expand(),
                            )
                          : Center(
                              child: Container(
                                height: 30,
                                decoration: BoxDecoration(
                                  gradient: LinearGradient(colors: [
                                    theme.colorScheme.primary.withOpacity(0.3),
                                    theme.colorScheme.primary.withOpacity(0.6),
                                    theme.colorScheme.primary.withOpacity(0.3),
                                  ]),
                                ),
                              ),
                            ),
                    ),
                    if (c.maxWidth > 0 && toplamSure > 0)
                      Positioned(
                        left: (_playheadZamani / toplamSure) * c.maxWidth - 1,
                        top: 0,
                        bottom: 0,
                        width: 2,
                        child: Container(color: Colors.red.shade500),
                      ),
                  ],
                ),
              ),
            );
          }),
          // Segment ribbon
          SizedBox(
            height: 40,
            child: LayoutBuilder(
              builder: (ctx, c) {
                return Stack(
                  children: proje.segmentler.map((s) {
                    final basla = (_suruklenenSegmentId == s.id &&
                            _suruklenenSolKenar &&
                            _suruklenenYeniDeger != null)
                        ? _suruklenenYeniDeger!
                        : s.basla;
                    final bit = (_suruklenenSegmentId == s.id &&
                            !_suruklenenSolKenar &&
                            _suruklenenYeniDeger != null)
                        ? _suruklenenYeniDeger!
                        : s.bit;
                    final solOran = basla / toplamSure;
                    final genisOran = (bit - basla) / toplamSure;
                    final secili = s.id == secId;
                    final bg = _segRenk(s, theme);
                    return Positioned(
                      left: c.maxWidth * solOran,
                      width: (c.maxWidth * genisOran).clamp(2.0, c.maxWidth),
                      top: 0,
                      bottom: 0,
                      child: Padding(
                        padding: const EdgeInsets.symmetric(horizontal: 1),
                        child: Stack(
                          children: [
                            Positioned.fill(
                              child: GestureDetector(
                                onTap: () => ref
                                    .read(secilenSegmentIdProvider.notifier)
                                    .state = s.id,
                                child: Container(
                                  decoration: BoxDecoration(
                                    color: bg,
                                    borderRadius: BorderRadius.circular(4),
                                    border: secili
                                        ? Border.all(
                                            color: Colors.amber, width: 2)
                                        : null,
                                  ),
                                  padding: const EdgeInsets.symmetric(
                                      horizontal: 4, vertical: 2),
                                  child: Column(
                                    crossAxisAlignment:
                                        CrossAxisAlignment.start,
                                    children: [
                                      Text(
                                        'S${s.sira + 1}',
                                        style: const TextStyle(
                                          color: Colors.white,
                                          fontSize: 10,
                                          fontWeight: FontWeight.bold,
                                        ),
                                      ),
                                      if (s.analizMeta?.enerjiSeviyesi != null)
                                        Text(
                                          s.analizMeta!.enerjiSeviyesi!,
                                          style: const TextStyle(
                                            color: Colors.white70,
                                            fontSize: 8,
                                          ),
                                        ),
                                    ],
                                  ),
                                ),
                              ),
                            ),
                            // Sol kenar tutamacı
                            Positioned(
                              left: 0,
                              top: 0,
                              bottom: 0,
                              width: 6,
                              child: MouseRegion(
                                cursor: SystemMouseCursors.resizeLeftRight,
                                child: GestureDetector(
                                  behavior: HitTestBehavior.opaque,
                                  onPanStart: (_) {
                                    _suruklenenSegmentId = s.id;
                                    _suruklenenSolKenar = true;
                                    _suruklenenYeniDeger = s.basla;
                                  },
                                  onPanUpdate: (d) => _kenarSurukle(
                                      s, true, d.delta.dx, c.maxWidth,
                                      toplamSure, beatler, proje),
                                  onPanEnd: (_) =>
                                      _kenarSurukleBitti(proje, true),
                                ),
                              ),
                            ),
                            // Sağ kenar tutamacı
                            Positioned(
                              right: 0,
                              top: 0,
                              bottom: 0,
                              width: 6,
                              child: MouseRegion(
                                cursor: SystemMouseCursors.resizeLeftRight,
                                child: GestureDetector(
                                  behavior: HitTestBehavior.opaque,
                                  onPanStart: (_) {
                                    _suruklenenSegmentId = s.id;
                                    _suruklenenSolKenar = false;
                                    _suruklenenYeniDeger = s.bit;
                                  },
                                  onPanUpdate: (d) => _kenarSurukle(
                                      s, false, d.delta.dx, c.maxWidth,
                                      toplamSure, beatler, proje),
                                  onPanEnd: (_) =>
                                      _kenarSurukleBitti(proje, false),
                                ),
                              ),
                            ),
                          ],
                        ),
                      ),
                    );
                  }).toList(),
                );
              },
            ),
          ),
        ],
      ),
    );
  }

  // ---- Etkileşim yardımcıları ----

  void _cetvelTiklandi(
      Offset pos, double w, double toplamSure, dynamic proje) {
    if (w <= 0) return;
    final t = (pos.dx / w * toplamSure).clamp(0.0, toplamSure);
    setState(() => _playheadZamani = t);
    final seg = _zamanaEnYakinSegment(proje.segmentler, t);
    if (seg != null) {
      ref.read(secilenSegmentIdProvider.notifier).state = seg.id;
    }
  }

  void _waveformTiklandi(
      Offset pos, double w, double toplamSure, dynamic proje) {
    if (w <= 0) return;
    final t = (pos.dx / w * toplamSure).clamp(0.0, toplamSure);
    setState(() => _playheadZamani = t);
    final seg = _zamanaEnYakinSegment(proje.segmentler, t);
    if (seg != null && seg.id != ref.read(secilenSegmentIdProvider)) {
      ref.read(secilenSegmentIdProvider.notifier).state = seg.id;
    }
  }

  Segment? _zamanaEnYakinSegment(List<Segment> segmentler, double t) {
    for (final s in segmentler) {
      if (s.basla <= t && t <= s.bit) return s;
    }
    Segment? enYakin;
    double enKucukFark = double.infinity;
    for (final s in segmentler) {
      final orta = (s.basla + s.bit) / 2;
      final fark = (orta - t).abs();
      if (fark < enKucukFark) {
        enKucukFark = fark;
        enYakin = s;
      }
    }
    return enYakin;
  }

  double _beatSnap(double t, List<double> beatler) {
    if (!_beatSnapAcik || beatler.isEmpty) return t;
    double enYakin = beatler.first;
    double enKucukFark = (beatler.first - t).abs();
    for (final b in beatler) {
      final f = (b - t).abs();
      if (f < enKucukFark) {
        enKucukFark = f;
        enYakin = b;
      }
    }
    return enKucukFark <= 0.15 ? enYakin : t;
  }

  void _kenarSurukle(Segment s, bool sol, double deltaPx, double w,
      double toplamSure, List<double> beatler, dynamic proje) {
    if (w <= 0) return;
    final deltaT = deltaPx / w * toplamSure;
    double yeniDeger = (_suruklenenYeniDeger ?? (sol ? s.basla : s.bit)) + deltaT;
    yeniDeger = _beatSnap(yeniDeger, beatler);

    // Sınır kontrolü
    if (sol) {
      final altSinir = _oncekiSegmentBaslangic(proje.segmentler, s);
      yeniDeger = yeniDeger.clamp(altSinir, s.bit - 0.05);
    } else {
      final ustSinir = _sonrakiSegmentBitis(proje.segmentler, s);
      yeniDeger = yeniDeger.clamp(s.basla + 0.05, ustSinir);
    }

    setState(() => _suruklenenYeniDeger = yeniDeger);
  }

  double _oncekiSegmentBaslangic(List<Segment> segs, Segment s) {
    final idx = segs.indexWhere((e) => e.id == s.id);
    if (idx <= 0) return 0;
    return segs[idx - 1].basla + 0.05;
  }

  double _sonrakiSegmentBitis(List<Segment> segs, Segment s) {
    final idx = segs.indexWhere((e) => e.id == s.id);
    if (idx < 0 || idx >= segs.length - 1) return segs.last.bit;
    return segs[idx + 1].bit - 0.05;
  }

  Future<void> _kenarSurukleBitti(dynamic proje, bool sol) async {
    final segId = _suruklenenSegmentId;
    final yeniDeger = _suruklenenYeniDeger;
    setState(() {
      _suruklenenSegmentId = null;
      _suruklenenYeniDeger = null;
    });
    if (segId == null || yeniDeger == null) return;

    final segs = List<Segment>.from(proje.segmentler);
    final idx = segs.indexWhere((e) => e.id == segId);
    if (idx < 0) return;
    final s = segs[idx];

    Segment guncellenen;
    if (sol) {
      guncellenen = s.copyWith(
        basla: yeniDeger,
        durum: s.durum == SegmentDurum.tamam ? SegmentDurum.bos : s.durum,
      );
      segs[idx] = guncellenen;
      // Önceki segment chained mı?
      if (idx > 0 && (segs[idx - 1].bit - s.basla).abs() < 0.001) {
        segs[idx - 1] = segs[idx - 1].copyWith(
          bit: yeniDeger,
          durum: segs[idx - 1].durum == SegmentDurum.tamam
              ? SegmentDurum.bos
              : segs[idx - 1].durum,
        );
      }
    } else {
      guncellenen = s.copyWith(
        bit: yeniDeger,
        durum: s.durum == SegmentDurum.tamam ? SegmentDurum.bos : s.durum,
      );
      segs[idx] = guncellenen;
      // Sonraki segment chained mı?
      if (idx < segs.length - 1 &&
          (segs[idx + 1].basla - s.bit).abs() < 0.001) {
        segs[idx + 1] = segs[idx + 1].copyWith(
          basla: yeniDeger,
          durum: segs[idx + 1].durum == SegmentDurum.tamam
              ? SegmentDurum.bos
              : segs[idx + 1].durum,
        );
      }
    }

    final guncel = proje.copyWith(segmentler: segs);
    ref.read(projeProvider.notifier).ayarlaBypass(guncel);
    await ProjeDeposu.kaydet(guncel);
  }

  List<double> _beatlerHesapla(dynamic proje, double toplamSure) {
    final analiz = proje.analiz;
    try {
      final dynamic beatList = analiz.beats;
      if (beatList is List && beatList.isNotEmpty) {
        return List<double>.from(beatList.map((e) => (e as num).toDouble()));
      }
    } catch (_) {}
    double bpm = 0;
    try {
      bpm = (proje.global.bpm as num?)?.toDouble() ?? 0;
    } catch (_) {
      bpm = 0;
    }
    if (bpm <= 0) {
      try {
        bpm = (analiz.bpm as num?)?.toDouble() ?? 0;
      } catch (_) {}
    }
    if (bpm <= 0) return [];
    final t = 60.0 / bpm;
    final liste = <double>[];
    for (double k = 0; k <= toplamSure; k += t) {
      liste.add(k);
    }
    return liste;
  }

  Color _segRenk(Segment s, ThemeData theme) {
    if (s.durum == SegmentDurum.tamam) {
      return theme.colorScheme.primary.withOpacity(0.7);
    }
    if (s.durum == SegmentDurum.uretiliyor) return Colors.amber.shade700;
    if (s.durum == SegmentDurum.kuyruk) return Colors.blue.shade700;
    if (s.durum == SegmentDurum.hata) return Colors.red.shade700;
    final sev = s.analizMeta?.enerjiSeviyesi;
    return switch (sev) {
      'silence' => Colors.grey.shade700,
      'low' => Colors.indigo.shade700,
      'medium' => Colors.teal.shade700,
      'high' => Colors.deepPurple.shade700,
      'climax' => Colors.pink.shade700,
      _ => theme.colorScheme.outline,
    };
  }
}

final Set<String> _hesaplananProjeler = {};

void _waveformCikartTetikle(WidgetRef ref, dynamic proje) {
  if (_hesaplananProjeler.contains(proje.id)) return;
  _hesaplananProjeler.add(proje.id);
  Future.microtask(() async {
    final rms = await WaveformOlusturucu.rmsAkisi(proje.kaynak.sesPath);
    if (rms.isEmpty) return;
    final guncel = proje.copyWith(
      analiz: proje.analiz.copyWith(
        rmsZamanlari: List.generate(rms.length, (i) => i.toDouble()),
        rmsDegerleri: rms,
        guncellendi: DateTime.now(),
      ),
    );
    await ProjeDeposu.kaydet(guncel);
    final aktifProje = ref.read(projeProvider);
    if (aktifProje?.id == proje.id) {
      ref.read(projeProvider.notifier).ayarlaBypass(guncel);
    }
  });
}

class _CetvelCizici extends CustomPainter {
  final double toplamSure;
  final Color renk;
  final double? playheadX;
  _CetvelCizici({required this.toplamSure, required this.renk, this.playheadX});

  @override
  void paint(Canvas canvas, Size size) {
    final paint = Paint()
      ..color = renk
      ..strokeWidth = 1;
    final adim = toplamSure / 12;
    for (int i = 0; i <= 12; i++) {
      final x = i * size.width / 12;
      canvas.drawLine(Offset(x, 0), Offset(x, 6), paint);
      final t = (i * adim).toStringAsFixed(0);
      final tp = TextPainter(
        text: TextSpan(
          text: '${t}s',
          style: TextStyle(color: renk, fontSize: 9),
        ),
        textDirection: TextDirection.ltr,
      )..layout();
      tp.paint(canvas, Offset(x + 2, 4));
    }
    if (playheadX != null) {
      final ph = Paint()
        ..color = Colors.red.shade500
        ..strokeWidth = 2;
      canvas.drawLine(
          Offset(playheadX!, 0), Offset(playheadX!, size.height), ph);
    }
  }

  @override
  bool shouldRepaint(covariant _CetvelCizici old) =>
      old.playheadX != playheadX || old.toplamSure != toplamSure;
}

class _WaveformCizici extends CustomPainter {
  final List<double> rms;
  final Color renk;
  _WaveformCizici({required this.rms, required this.renk});

  @override
  void paint(Canvas canvas, Size size) {
    if (rms.isEmpty) return;
    final paint = Paint()
      ..color = renk
      ..strokeWidth = 1.5;
    final maxDb = rms.reduce((a, b) => a > b ? a : b);
    final minDb = rms.reduce((a, b) => a < b ? a : b);
    final range = (maxDb - minDb).abs() < 1 ? 1.0 : (maxDb - minDb).abs();
    final cy = size.height / 2;
    for (int i = 0; i < rms.length; i++) {
      final x = i * size.width / rms.length;
      final norm = (rms[i] - minDb) / range;
      final h = norm * size.height * 0.9;
      canvas.drawLine(Offset(x, cy - h / 2), Offset(x, cy + h / 2), paint);
    }
  }

  @override
  bool shouldRepaint(_) => false;
}