// =============================================================================
//  screens/cockpit/cockpit_screen.dart — AR-Autopilot main cockpit view
// =============================================================================
//
//  Sprint 4: static layout with demo data (AutopilotState simulation).
//  Sprint 7: AutopilotState internals replaced by Modbus RTU over USB serial.
//
//  Layout (top → bottom):
//    TopBar        — logo, title, NMEA/GPS status, settings gear
//    ModeSelector  — STANDBY | HDG HOLD | TRACK
//    CompassRose   — dominant visual; shows heading + setpoint tick
//    DataStrip     — SOG · COG · ROT · DEPTH
//    HeadingAdjust — << < [SET 048°] > >>
//    RudderRow     — label + horizontal rudder indicator
//    ActionRow     — [ ENGAGE ]   [ DISENGAGE ]
// =============================================================================

import 'dart:async';

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

import '../../data/autopilot_state.dart';
import '../../theme/autopilot_theme.dart';
import '../../theme/theme_provider.dart';
import '../../widgets/themed/compass_rose.dart';
import '../../widgets/themed/disengage_button.dart';
import '../../widgets/themed/engage_button.dart';
import '../../widgets/themed/heading_adjust_bar.dart';
import '../../widgets/themed/mode_selector.dart';
import '../../widgets/themed/rudder_indicator.dart';
import '../../widgets/themed/status_chip.dart';
import '../settings/appearance_settings.dart';
import '../settings/port_settings_screen.dart';

class CockpitScreen extends StatelessWidget {
  const CockpitScreen({super.key});

  static const String routeName = '/';

  @override
  Widget build(BuildContext context) {
    final theme = context.watch<AutopilotThemeProvider>().current;
    final ap = context.watch<AutopilotState>();

    return Scaffold(
      backgroundColor: theme.background,
      body: AnimatedContainer(
        duration: const Duration(milliseconds: 400),
        curve: Curves.easeInOut,
        decoration: theme.backgroundDecoration,
        child: SafeArea(
          child: Column(
            children: [
              _TopBar(theme: theme, ap: ap),
              Padding(
                padding: const EdgeInsets.fromLTRB(16, 10, 16, 0),
                child: ModeSelector(
                  activeMode: ap.mode,
                  onModeSelected: ap.selectMode,
                ),
              ),
              Expanded(
                child: _CockpitBody(theme: theme, ap: ap),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

// ── Top bar ───────────────────────────────────────────────────────────────────

class _TopBar extends StatelessWidget {
  const _TopBar({required this.theme, required this.ap});

  final AutopilotTheme theme;
  final AutopilotState ap;

  @override
  Widget build(BuildContext context) {
    return Container(
      height: 54,
      padding: const EdgeInsets.symmetric(horizontal: 16),
      decoration: BoxDecoration(
        color: theme.backgroundMid.withValues(alpha: 0.9),
        border: Border(
          bottom: BorderSide(color: theme.panelBorder, width: 0.5),
        ),
      ),
      child: Row(
        children: [
          // Logo — triple-tap cycles themes (design invariant from Sprint 3)
          _ThemeCycleLogo(theme: theme),
          const SizedBox(width: 10),
          Text(
            'AR-AUTOPILOT',
            style: TextStyle(
              color: theme.textMain,
              fontSize: 14,
              fontWeight: FontWeight.w700,
              letterSpacing: 1.8,
            ),
          ),
          if (!ap.isConnected) ...[
            const SizedBox(width: 8),
            Container(
              padding: const EdgeInsets.symmetric(horizontal: 6, vertical: 2),
              decoration: BoxDecoration(
                color: theme.warnColor.withValues(alpha: 0.15),
                borderRadius: BorderRadius.circular(4),
                border: Border.all(
                  color: theme.warnColor.withValues(alpha: 0.4),
                ),
              ),
              child: Text(
                'DEMO',
                style: TextStyle(
                  color: theme.warnColor,
                  fontSize: 9,
                  fontWeight: FontWeight.w700,
                  letterSpacing: 1,
                ),
              ),
            ),
          ],
          const Spacer(),
          StatusChip(
            theme: theme,
            label: 'NMEA',
            status: ap.isConnected ? StatusLevel.ok : StatusLevel.off,
          ),
          const SizedBox(width: 14),
          StatusChip(
            theme: theme,
            label: 'GPS',
            status: ap.isConnected ? StatusLevel.ok : StatusLevel.warn,
          ),
          const SizedBox(width: 16),
          PopupMenuButton<String>(
            icon: Icon(
              Icons.settings_outlined,
              color: theme.textMuted,
              size: 22,
            ),
            color: theme.backgroundMid,
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(8),
              side: BorderSide(color: theme.panelBorder),
            ),
            onSelected: (route) => Navigator.pushNamed(context, route),
            itemBuilder: (_) => [
              PopupMenuItem(
                value: PortSettingsScreen.routeName,
                child: Row(
                  children: [
                    Icon(Icons.usb, color: theme.accentMid, size: 18),
                    const SizedBox(width: 10),
                    Text(
                      'Puertos COM',
                      style: TextStyle(color: theme.textMain, fontSize: 13),
                    ),
                  ],
                ),
              ),
              PopupMenuItem(
                value: AppearanceSettingsScreen.routeName,
                child: Row(
                  children: [
                    Icon(Icons.palette_outlined,
                        color: theme.accentMid, size: 18),
                    const SizedBox(width: 10),
                    Text(
                      'Apariencia',
                      style: TextStyle(color: theme.textMain, fontSize: 13),
                    ),
                  ],
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }
}

/// AR Electronics logo that cycles themes on triple-tap.
///
/// Counts taps within 600 ms; three rapid taps rotate through the 4 themes.
/// This implements the shortcut described in [AppearanceSettingsScreen].
class _ThemeCycleLogo extends StatefulWidget {
  const _ThemeCycleLogo({required this.theme});

  final AutopilotTheme theme;

  @override
  State<_ThemeCycleLogo> createState() => _ThemeCycleLogoState();
}

class _ThemeCycleLogoState extends State<_ThemeCycleLogo> {
  static const _kWindow = Duration(milliseconds: 600);
  static const _kIds = ['light', 'cyan', 'wine', 'ochre'];

  int _taps = 0;
  Timer? _resetTimer;

  void _onTap() {
    _resetTimer?.cancel();
    _taps++;
    if (_taps >= 3) {
      _taps = 0;
      final provider = context.read<AutopilotThemeProvider>();
      final idx = _kIds.indexOf(provider.current.id);
      provider.setTheme(_kIds[(idx + 1) % _kIds.length]);
    } else {
      _resetTimer = Timer(_kWindow, () => _taps = 0);
    }
  }

  @override
  void dispose() {
    _resetTimer?.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: _onTap,
      child: Image.asset(
        'assets/images/ar_logo_full.png',
        height: 34,
        errorBuilder: (_, __, ___) => Icon(
          Icons.anchor,
          color: widget.theme.accentMid,
          size: 28,
        ),
      ),
    );
  }
}

// ── Cockpit body ──────────────────────────────────────────────────────────────

class _CockpitBody extends StatelessWidget {
  const _CockpitBody({required this.theme, required this.ap});

  final AutopilotTheme theme;
  final AutopilotState ap;

  bool get _engaged => ap.mode != AutopilotMode.standby;

  @override
  Widget build(BuildContext context) {
    return LayoutBuilder(
      builder: (context, constraints) {
        // Compass scales between 200 and 320 px based on available width.
        final compassSize =
            (constraints.maxWidth * 0.68).clamp(200.0, 320.0);

        return SingleChildScrollView(
          padding: const EdgeInsets.fromLTRB(16, 14, 16, 16),
          child: Column(
            children: [
              // ── Compass rose ─────────────────────────────────────────────
              Center(
                child: CompassRose(
                  headingDeg: ap.headingDeg,
                  setPointDeg: _engaged ? ap.setpointDeg : null,
                  size: compassSize,
                ),
              ),
              const SizedBox(height: 14),

              // ── Instrument data strip ────────────────────────────────────
              _DataStrip(theme: theme, ap: ap),
              const SizedBox(height: 14),

              // ── Heading setpoint + adjust buttons ────────────────────────
              HeadingAdjustBar(
                setpointDeg: ap.setpointDeg,
                enabled: _engaged,
                onAdjust: ap.adjustSetpoint,
              ),
              const SizedBox(height: 14),

              // ── Rudder indicator ─────────────────────────────────────────
              _RudderRow(theme: theme, rudderDeg: ap.rudderDeg),
              const SizedBox(height: 20),

              // ── ENGAGE / DISENGAGE row ───────────────────────────────────
              Row(
                children: [
                  Expanded(
                    child: EngageButton(
                      onPressed: !_engaged ? ap.engage : null,
                      enabled: !_engaged,
                    ),
                  ),
                  const SizedBox(width: 14),
                  Expanded(
                    child: DisengageButton(
                      onPressed: _engaged ? ap.disengage : null,
                      enabled: _engaged,
                    ),
                  ),
                ],
              ),
            ],
          ),
        );
      },
    );
  }
}

// ── Data strip ────────────────────────────────────────────────────────────────

class _DataStrip extends StatelessWidget {
  const _DataStrip({required this.theme, required this.ap});

  final AutopilotTheme theme;
  final AutopilotState ap;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
      decoration: BoxDecoration(
        gradient: theme.panelBackground,
        borderRadius: BorderRadius.circular(8),
        border: Border.all(color: theme.panelBorder),
      ),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceAround,
        children: [
          _DataCell(
            theme: theme,
            label: 'SOG',
            value: '${ap.sogKn.toStringAsFixed(1)} kn',
          ),
          _VerticalDivider(theme: theme),
          _DataCell(
            theme: theme,
            label: 'COG',
            value: '${ap.cogDeg.toStringAsFixed(0).padLeft(3, '0')}°',
          ),
          _VerticalDivider(theme: theme),
          _DataCell(
            theme: theme,
            label: 'ROT',
            value: '${ap.rotDpm.toStringAsFixed(1)}°/m',
          ),
          _VerticalDivider(theme: theme),
          _DataCell(
            theme: theme,
            label: 'PROF',
            value: '${ap.depthM.toStringAsFixed(1)} m',
          ),
        ],
      ),
    );
  }
}

class _VerticalDivider extends StatelessWidget {
  const _VerticalDivider({required this.theme});

  final AutopilotTheme theme;

  @override
  Widget build(BuildContext context) =>
      Container(width: 1, height: 30, color: theme.panelBorder);
}

class _DataCell extends StatelessWidget {
  const _DataCell({
    required this.theme,
    required this.label,
    required this.value,
  });

  final AutopilotTheme theme;
  final String label;
  final String value;

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        Text(
          label,
          style: TextStyle(
            color: theme.textMuted,
            fontSize: 9,
            letterSpacing: 1.2,
            fontWeight: FontWeight.w600,
          ),
        ),
        const SizedBox(height: 3),
        Text(
          value,
          style: TextStyle(
            color: theme.textMain,
            fontSize: 15,
            fontWeight: FontWeight.w300,
            fontFeatures: const [FontFeature.tabularFigures()],
          ),
        ),
      ],
    );
  }
}

// ── Rudder row ────────────────────────────────────────────────────────────────

class _RudderRow extends StatelessWidget {
  const _RudderRow({required this.theme, required this.rudderDeg});

  final AutopilotTheme theme;
  final double rudderDeg;

  String _label(double deg) {
    if (deg.abs() < 0.5) return 'CENTRO';
    final side = deg < 0 ? 'BABOR' : 'ESTRIBOR';
    return '${deg.abs().toStringAsFixed(1)}°  $side';
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        Row(
          children: [
            Text(
              'TIMÓN',
              style: TextStyle(
                color: theme.textMuted,
                fontSize: 9,
                letterSpacing: 1.2,
                fontWeight: FontWeight.w600,
              ),
            ),
            const Spacer(),
            Text(
              _label(rudderDeg),
              style: TextStyle(
                color: theme.textSoft,
                fontSize: 12,
                fontFeatures: const [FontFeature.tabularFigures()],
              ),
            ),
          ],
        ),
        const SizedBox(height: 6),
        RudderIndicator(rudderDeg: rudderDeg),
      ],
    );
  }
}