import 'package:flutter/material.dart';
import '../../../models/energy_data.dart';
import '../../../theme/etm_tokens.dart';
import '../../../shared/widgets/hems_icon.dart';
import '../painters/flow_painter.dart';

enum _DrillView { overview, cons, prod }

class EnergyFlowCard extends StatefulWidget {
  final EnergyData data;

  /// Puissance **mesurée** de la borne de recharge (`currentPower` du Thing), ou `null`
  /// quand aucune borne n'est déclarée — ou qu'elle ne publie pas cet état.
  ///
  /// Elle valait 3,6 kW en dur jusqu'au 2026-08-28 : `EnergyData.chargingPower` était une
  /// valeur par défaut que rien ne remplaçait, et le Sankey dessinait donc en permanence
  /// un flux vers une voiture qui n'était pas branchée.
  final double? evChargerPowerW;
  const EnergyFlowCard(
      {super.key, required this.data, this.evChargerPowerW});

  @override
  State<EnergyFlowCard> createState() => _EnergyFlowCardState();
}

class _EnergyFlowCardState extends State<EnergyFlowCard>
    with TickerProviderStateMixin {
  late final AnimationController _particleCtrl;
  late final AnimationController _pulseCtrl;
  late final Animation<double>   _pulseAnim;
  _DrillView _view = _DrillView.overview;

  @override
  void initState() {
    super.initState();
    _particleCtrl = AnimationController(
      vsync: this,
      duration: const Duration(milliseconds: 2800),
    )..repeat();
    _pulseCtrl = AnimationController(
      vsync: this,
      duration: const Duration(milliseconds: 3000),
    )..repeat(reverse: true);
    _pulseAnim = Tween<double>(begin: 0.22, end: 0.55)
        .animate(CurvedAnimation(parent: _pulseCtrl, curve: Curves.easeInOut));
  }

  @override
  void dispose() {
    _particleCtrl.dispose();
    _pulseCtrl.dispose();
    super.dispose();
  }

  void _switchView(_DrillView v) => setState(() => _view = v);

  String get _viewTitle => switch (_view) {
    _DrillView.overview => 'Flux énergétique',
    _DrillView.cons     => 'Consommation — détail',
    _DrillView.prod     => 'Production — détail',
  };

  @override
  Widget build(BuildContext context) {
    final disableAnim = MediaQuery.of(context).disableAnimations;
    final eco  = EtmTokens.ecoOf(context);
    final line = EtmTokens.lineOf(context);
    final surf = EtmTokens.surfaceOf(context);
    final ink  = EtmTokens.inkOf(context);
    final muted = EtmTokens.mutedOf(context);

    return Container(
      decoration: BoxDecoration(
        color: surf,
        borderRadius: BorderRadius.circular(EtmTokens.radiusCard),
        boxShadow: EtmTokens.cardShadowOf(context),
        border: Border.all(color: line, width: 1),
      ),
      padding: const EdgeInsets.fromLTRB(16, 14, 16, 10),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          // ── Header ─────────────────────────────────────────────────────────
          Row(
            children: [
              if (_view != _DrillView.overview) ...[
                GestureDetector(
                  onTap: () => _switchView(_DrillView.overview),
                  child: Container(
                    width: 32, height: 32,
                    decoration: BoxDecoration(
                      borderRadius: BorderRadius.circular(10),
                      border: Border.all(color: line, width: 1),
                    ),
                    child: Icon(Icons.chevron_left_rounded, size: 20, color: ink),
                  ),
                ),
                const SizedBox(width: 10),
              ],
              Expanded(
                child: Text(_viewTitle,
                    style: EtmTokens.sans(size: 13, weight: FontWeight.w600, color: ink)),
              ),
              AnimatedBuilder(
                animation: _pulseAnim,
                builder: (context, _) => Container(
                  width: 7, height: 7,
                  decoration: BoxDecoration(
                    shape: BoxShape.circle,
                    color: eco.withValues(alpha: disableAnim ? 0.6 : _pulseAnim.value),
                  ),
                ),
              ),
              const SizedBox(width: 6),
              Text('en direct',
                  style: EtmTokens.mono(size: 11, color: muted)),
            ],
          ),
          const SizedBox(height: 4),

          // ── Flow diagram ────────────────────────────────────────────────────
          AspectRatio(
            aspectRatio: 1,
            child: LayoutBuilder(
              builder: (context, constraints) {
                final size = constraints.maxWidth;
                final segments =
                    _buildSegments(widget.data, _view, widget.evChargerPowerW);
                return AnimatedBuilder(
                  animation: _particleCtrl,
                  builder: (context, _) {
                    final animVal = disableAnim ? 0.0 : _particleCtrl.value;
                    return Stack(
                      children: [
                        CustomPaint(
                          size: Size(size, size),
                          painter: FlowPainter(
                            segments: segments,
                            animValue: animVal,
                            lineColor: EtmTokens.lineStrongOf(context),
                          ),
                        ),
                        AnimatedSwitcher(
                          duration: const Duration(milliseconds: 220),
                          transitionBuilder: (child, anim) => FadeTransition(
                            opacity: anim,
                            child: ScaleTransition(
                              scale: anim.drive(Tween(begin: 0.88, end: 1.0)),
                              child: child,
                            ),
                          ),
                          child: _NodeLayer(
                            key: ValueKey(_view),
                            view: _view,
                            data: widget.data,
                            evChargerPowerW: widget.evChargerPowerW,
                            pulseAnim: disableAnim ? null : _pulseAnim,
                            onTapSolar:  () => _switchView(_DrillView.prod),
                            onTapMaison: () => _switchView(_DrillView.cons),
                          ),
                        ),
                      ],
                    );
                  },
                );
              },
            ),
          ),

          // ── Hint (overview only) ────────────────────────────────────────────
          if (_view == _DrillView.overview)
            Padding(
              padding: const EdgeInsets.only(top: 8),
              child: Text.rich(
                TextSpan(
                  style: EtmTokens.sans(size: 11, color: muted),
                  children: [
                    const TextSpan(text: 'Touchez '),
                    TextSpan(
                      text: 'Maison',
                      style: EtmTokens.sans(
                          size: 11, weight: FontWeight.w600, color: EtmTokens.brand),
                    ),
                    const TextSpan(text: ' ou '),
                    TextSpan(
                      text: 'Solaire',
                      style: EtmTokens.sans(
                          size: 11, weight: FontWeight.w600, color: EtmTokens.solar),
                    ),
                    const TextSpan(text: ' pour détailler'),
                  ],
                ),
                textAlign: TextAlign.center,
              ),
            ),
        ],
      ),
    );
  }

  // Edge-to-edge coordinates matching HTML EDGE dict ÷100
  // nE = 0.22 (satellite inner edge), hE = 0.39 (hub outer edge)
  static const double _nE = 0.22;
  static const double _hE = 0.39;

  static List<FlowSegment> _buildSegments(
      EnergyData d, _DrillView view, double? evW) {
    const nE = _nE;
    const hE = _hE;

    switch (view) {
      case _DrillView.overview:
        final gridImport = (-d.gridPower).clamp(0.0, double.infinity);
        final gridExport =   d.gridPower.clamp(0.0, double.infinity);
        final battCharge =   d.batteryPower.clamp(0.0, double.infinity);
        final battDisch  = (-d.batteryPower).clamp(0.0, double.infinity);
        return [
          FlowSegment(from: Offset(0.5, nE),    to: Offset(0.5, hE),    color: EtmTokens.solar,      powerW: d.pvPower),
          FlowSegment(from: Offset(nE, 0.5),    to: Offset(hE, 0.5),    color: EtmTokens.importColor, powerW: gridImport),
          FlowSegment(from: Offset(hE, 0.5),    to: Offset(nE, 0.5),    color: EtmTokens.solToGrid,   powerW: gridExport),
          FlowSegment(from: Offset(1-hE, 0.5),  to: Offset(1-nE, 0.5),  color: EtmTokens.eco,         powerW: battCharge),
          FlowSegment(from: Offset(1-nE, 0.5),  to: Offset(1-hE, 0.5),  color: EtmTokens.battToHouse, powerW: battDisch),
          FlowSegment(from: Offset(0.5, 1-hE),  to: Offset(0.5, 1-nE),  color: EtmTokens.brand,       powerW: d.homePower),
        ];

      case _DrillView.cons:
        final total = d.homePower.clamp(1.0, double.infinity);
        return [
          FlowSegment(from: Offset(0.5, hE),    to: Offset(0.5, nE),    color: EtmTokens.heat,     powerW: total * 0.38),
          FlowSegment(from: Offset(1-hE, 0.5),  to: Offset(1-nE, 0.5),  color: EtmTokens.water,    powerW: total * 0.18),
          FlowSegment(from: Offset(0.5, 1-hE),  to: Offset(0.5, 1-nE),  color: EtmTokens.eco,      powerW: evW ?? 0),
          FlowSegment(from: Offset(hE, 0.5),    to: Offset(nE, 0.5),    color: EtmTokens.gridColor, powerW: total * 0.22, dashed: true),
        ];

      case _DrillView.prod:
        final half = d.pvPower / 2;
        return [
          FlowSegment(from: Offset(nE, 0.5),   to: Offset(hE, 0.5),   color: EtmTokens.solar, powerW: half),
          FlowSegment(from: Offset(1-nE, 0.5), to: Offset(1-hE, 0.5), color: EtmTokens.solar, powerW: half),
        ];
    }
  }
}

// ── Node layer ────────────────────────────────────────────────────────────────

class _NodeLayer extends StatefulWidget {
  final _DrillView view;
  final EnergyData data;

  /// Puissance mesurée de la borne — `null` = non lue. Voir [EnergyFlowCard].
  final double? evChargerPowerW;
  final Animation<double>? pulseAnim;
  final VoidCallback onTapSolar;
  final VoidCallback onTapMaison;

  const _NodeLayer({
    super.key,
    required this.view,
    required this.data,
    required this.evChargerPowerW,
    required this.pulseAnim,
    required this.onTapSolar,
    required this.onTapMaison,
  });

  @override
  State<_NodeLayer> createState() => _NodeLayerState();
}

class _NodeLayerState extends State<_NodeLayer>
    with SingleTickerProviderStateMixin {
  late final AnimationController _enterCtrl;

  @override
  void initState() {
    super.initState();
    _enterCtrl = AnimationController(
      vsync: this,
      duration: const Duration(milliseconds: 600),
    )..forward();
  }

  @override
  void dispose() {
    _enterCtrl.dispose();
    super.dispose();
  }

  Animation<double> _stagger(int i) => CurvedAnimation(
        parent: _enterCtrl,
        curve: Interval(
          (i * 0.08).clamp(0.0, 0.6),
          ((i * 0.08) + 0.55).clamp(0.0, 1.0),
          curve: Curves.easeOutBack,
        ),
      );

  @override
  Widget build(BuildContext context) {
    return switch (widget.view) {
      _DrillView.overview => _buildOverview(context),
      _DrillView.cons     => _buildCons(context),
      _DrillView.prod     => _buildProd(context),
    };
  }

  Widget _buildOverview(BuildContext context) {
    final d   = widget.data;
    final eco = EtmTokens.ecoOf(context);
    return Stack(children: [
      // Hub — Héos with pulsing ring
      _at(Offset(0.5, 0.5), _buildHub(context, eco)),
      // Solar (top) — tappable → prod
      _at(Offset(0.5, 0.12),
          ScaleTransition(scale: _stagger(0),
            child: GestureDetector(
              onTap: widget.onTapSolar,
              child: _sat(context,
                icon: Icons.wb_sunny_rounded,
                color: EtmTokens.solarOf(context),
                label: 'Solaire',
                value: '${(d.pvPower / 1000).toStringAsFixed(1)} kW',
                tappable: true,
              ),
            ),
          )),
      // Battery (right)
      _at(Offset(0.88, 0.5),
          ScaleTransition(scale: _stagger(1),
            child: _sat(context,
              icon: Icons.battery_charging_full_rounded,
              color: eco,
              label: 'Batterie',
              value: '${d.batterySOC.toStringAsFixed(0)} %',
            ),
          )),
      // Grid (left) — neutral border
      _at(Offset(0.12, 0.5),
          ScaleTransition(scale: _stagger(2),
            child: _sat(context,
              icon: Icons.home_outlined,
              color: EtmTokens.gridColor,
              label: 'Réseau',
              value: '${(d.gridPower.abs() / 1000).toStringAsFixed(1)} kW',
              borderColor: EtmTokens.lineOf(context),
            ),
          )),
      // Maison (bottom) — tappable → cons
      _at(Offset(0.5, 0.88),
          ScaleTransition(scale: _stagger(3),
            child: GestureDetector(
              onTap: widget.onTapMaison,
              child: _sat(context,
                icon: Icons.home_rounded,
                color: EtmTokens.brand,
                label: 'Maison',
                value: '${(d.homePower / 1000).toStringAsFixed(1)} kW',
                tappable: true,
              ),
            ),
          )),
    ]);
  }

  Widget _buildCons(BuildContext context) {
    final d     = widget.data;
    final total = d.homePower.clamp(1.0, double.infinity);
    return Stack(children: [
      // Hub — Maison
      _at(Offset(0.5, 0.5),
          ScaleTransition(scale: _stagger(0),
            child: _satHub(context,
              icon: Icons.home_rounded,
              color: EtmTokens.brand,
              label: 'Maison',
              value: '${(d.homePower / 1000).toStringAsFixed(1)} kW',
              borderColor: EtmTokens.lineOf(context),
            ),
          )),
      _at(Offset(0.5, 0.12), ScaleTransition(scale: _stagger(1),
          child: _sat(context, icon: Icons.heat_pump_outlined,     color: EtmTokens.heat,
              label: 'PAC',       value: '${(total * 0.38 / 1000).toStringAsFixed(1)} kW'))),
      _at(Offset(0.88, 0.5), ScaleTransition(scale: _stagger(2),
          child: _sat(context, icon: Icons.water_drop_outlined,    color: EtmTokens.water,
              label: 'Eau chaude', value: '${(total * 0.18 / 1000).toStringAsFixed(1)} kW'))),
      _at(Offset(0.5, 0.88), ScaleTransition(scale: _stagger(3),
          child: _sat(context, icon: Icons.ev_station_rounded,     color: eco(context),
              label: 'Voiture',
              // « non lu » plutôt qu'un zéro : sans borne déclarée, l'app ne sait pas
              // qu'il ne se charge rien — elle sait qu'elle ne mesure rien.
              value: widget.evChargerPowerW == null
                  ? 'non lu'
                  : '${(widget.evChargerPowerW! / 1000).toStringAsFixed(1)} kW'))),
      _at(Offset(0.12, 0.5), ScaleTransition(scale: _stagger(4),
          child: _sat(context, icon: Icons.devices_other_rounded,  color: EtmTokens.gridColor,
              label: 'Autres',    value: '${(total * 0.22 / 1000).toStringAsFixed(1)} kW',
              estimated: true))),
    ]);
  }

  Widget _buildProd(BuildContext context) {
    final d    = widget.data;
    final solar = EtmTokens.solarOf(context);
    final half  = d.pvPower / 2000;
    return Stack(children: [
      _at(Offset(0.5, 0.5),
          ScaleTransition(scale: _stagger(0),
            child: _satHub(context,
              icon: Icons.wb_sunny_rounded,
              color: solar,
              label: 'Solaire',
              value: '${(d.pvPower / 1000).toStringAsFixed(1)} kW',
              borderColor: EtmTokens.lineOf(context),
            ),
          )),
      _at(Offset(0.12, 0.5), ScaleTransition(scale: _stagger(1),
          child: _sat(context, icon: Icons.solar_power_rounded, color: solar,
              label: 'Onduleur 1', value: '${half.toStringAsFixed(1)} kW', state: _NodeState.ok))),
      _at(Offset(0.88, 0.5), ScaleTransition(scale: _stagger(2),
          child: _sat(context, icon: Icons.solar_power_rounded, color: solar,
              label: 'Onduleur 2', value: '${half.toStringAsFixed(1)} kW', state: _NodeState.ok))),
    ]);
  }

  Color eco(BuildContext context) => EtmTokens.ecoOf(context);

  // Position any widget by normalized (0..1) coordinates
  Widget _at(Offset pos, Widget child) => Align(
    alignment: Alignment(pos.dx * 2 - 1, pos.dy * 2 - 1),
    child: child,
  );

  // Hub node — 92px circle, surface bg, line border
  Widget _satHub(BuildContext context, {
    required IconData icon,
    required Color color,
    required String label,
    required String value,
    Color? borderColor,
  }) {
    final surf  = EtmTokens.surfaceOf(context);
    final muted = EtmTokens.mutedOf(context);
    final bdr   = borderColor ?? color.withValues(alpha: 0.4);
    return SizedBox(
      width: 92, height: 92,
      child: Container(
        decoration: BoxDecoration(
          shape: BoxShape.circle,
          color: surf,
          border: Border.all(color: bdr, width: 2),
        ),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Icon(icon, color: color, size: 22),
            const SizedBox(height: 2),
            Text(value, style: EtmTokens.mono(size: 13, weight: FontWeight.w600, color: color)),
            Text(label, style: EtmTokens.sans(size: 9, color: muted)),
          ],
        ),
      ),
    );
  }

  // Hub with Héos pulsing ring
  Widget _buildHub(BuildContext context, Color eco) {
    final surf  = EtmTokens.surfaceOf(context);
    final muted = EtmTokens.mutedOf(context);
    final line  = EtmTokens.lineOf(context);
    return SizedBox(
      width: 102, height: 102,
      child: Stack(
        alignment: Alignment.center,
        children: [
          // Pulsing Héos ring
          if (widget.pulseAnim != null)
            AnimatedBuilder(
              animation: widget.pulseAnim!,
              builder: (context, _) => Container(
                width: 102, height: 102,
                decoration: BoxDecoration(
                  shape: BoxShape.circle,
                  border: Border.all(
                    color: eco.withValues(alpha: widget.pulseAnim!.value),
                    width: 1.5,
                  ),
                ),
              ),
            ),
          // Hub circle — Héos
          Container(
            width: 92, height: 92,
            decoration: BoxDecoration(
              shape: BoxShape.circle,
              color: surf,
              border: Border.all(color: line, width: 2),
            ),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                HemsIcon(size: 24, color: eco),
                const SizedBox(height: 3),
                Text('Héos', style: EtmTokens.sans(size: 9, color: muted)),
              ],
            ),
          ),
        ],
      ),
    );
  }

  // Satellite node — 74px circle, content inside
  Widget _sat(BuildContext context, {
    required IconData icon,
    required Color color,
    required String label,
    required String value,
    Color? borderColor,
    bool tappable = false,
    bool estimated = false,
    _NodeState? state,
  }) {
    const size = 74.0;
    final surf  = EtmTokens.surfaceOf(context);
    final muted = EtmTokens.mutedOf(context);
    final bdr   = borderColor ?? color.withValues(alpha: 0.4);

    Widget circle = Container(
      width: size, height: size,
      decoration: BoxDecoration(
        shape: BoxShape.circle,
        color: surf,
        border: Border.all(
          color: estimated ? Colors.transparent : bdr,
          width: 1.5,
        ),
      ),
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Icon(icon, color: color, size: 21),
          const SizedBox(height: 1),
          Text(value, style: EtmTokens.mono(size: 11, weight: FontWeight.w600, color: color)),
          Text(label, style: EtmTokens.sans(size: 8.5, color: muted)),
        ],
      ),
    );

    if (estimated) {
      circle = CustomPaint(
        painter: _DashedBorderPainter(color: color, radius: size / 2),
        child: circle,
      );
    }

    return SizedBox(
      width: size, height: size,
      child: Stack(
        clipBehavior: Clip.none,
        children: [
          circle,
          if (tappable)
            Positioned(
              right: 2, top: 2,
              child: Container(
                width: 15, height: 15,
                decoration: BoxDecoration(
                  color: EtmTokens.brand,
                  shape: BoxShape.circle,
                  border: Border.all(color: surf, width: 1),
                ),
                child: const Center(
                  child: Icon(Icons.add, size: 9, color: Colors.white),
                ),
              ),
            ),
          if (state != null)
            Positioned(
              right: 4, bottom: 4,
              child: Container(
                width: 7, height: 7,
                decoration: BoxDecoration(
                  shape: BoxShape.circle,
                  color: state == _NodeState.ok ? EtmTokens.eco : EtmTokens.heat,
                  border: Border.all(color: surf, width: 1),
                ),
              ),
            ),
        ],
      ),
    );
  }
}

enum _NodeState { ok }

// ── Dashed border painter ─────────────────────────────────────────────────────

class _DashedBorderPainter extends CustomPainter {
  final Color color;
  final double radius;
  const _DashedBorderPainter({required this.color, required this.radius});

  @override
  void paint(Canvas canvas, Size size) {
    const dashCount = 16;
    final paint = Paint()
      ..color = color.withValues(alpha: 0.4)
      ..strokeWidth = 1.5
      ..style = PaintingStyle.stroke;
    final center = Offset(size.width / 2, size.height / 2);
    const step = 3.14159 * 2 / dashCount;
    for (int i = 0; i < dashCount; i += 2) {
      final start = i * step;
      canvas.drawArc(
        Rect.fromCircle(center: center, radius: radius),
        start,
        step * 0.6,
        false,
        paint,
      );
    }
  }

  @override
  bool shouldRepaint(_DashedBorderPainter old) => old.color != color;
}