import 'dart:async';

import 'package:flutter/material.dart';

import 'bridge/location_bridge.dart';
import 'preferences.dart';
import 'settings_screen.dart';
import 'status_screen.dart';

class MainScreen extends StatefulWidget {
  const MainScreen({super.key});

  @override
  State<MainScreen> createState() => _MainScreenState();
}

class _MainScreenState extends State<MainScreen> with TickerProviderStateMixin {
  StreamSubscription<Map<String, dynamic>>? _locationSubscription;
  bool _isTracking = false;
  String _lastLat = '--';
  String _lastLon = '--';
  String _lastSpeed = '--';
  String _lastTime = '--';

  late AnimationController _pulseController;
  late Animation<double> _pulseAnimation;

  @override
  void initState() {
    super.initState();
    _pulseController = AnimationController(
      duration: const Duration(milliseconds: 1400),
      vsync: this,
    )..repeat(reverse: true);
    _pulseAnimation = Tween<double>(begin: 0.6, end: 1.0).animate(
      CurvedAnimation(parent: _pulseController, curve: Curves.easeInOut),
    );
    _initLocationStream();
  }

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

  Future<void> _initLocationStream() async {
    final status = await LocationBridge.getStatus();
    if (mounted) {
      setState(() {
        _isTracking = status?['isTracking'] == true;
        final lat = status?['lastLatitude'];
        final lon = status?['lastLongitude'];
        if (lat != null && lat != 0.0) {
          _lastLat = lat.toStringAsFixed(5);
        }
        if (lon != null && lon != 0.0) {
          _lastLon = lon.toStringAsFixed(5);
        }
        final speed = status?['lastSpeed'];
        if (speed != null) {
          _lastSpeed = (speed * 3.6).toStringAsFixed(1);
        }
        final timestamp = status?['lastTimestamp'];
        if (timestamp != null) {
          _lastTime = _formatDateTime(
            DateTime.fromMillisecondsSinceEpoch(timestamp),
          );
        }
      });
    }

    _locationSubscription = LocationBridge.locationUpdates.listen((location) {
      if (mounted) {
        setState(() {
          _lastLat = location['latitude']?.toStringAsFixed(5) ?? '--';
          _lastLon = location['longitude']?.toStringAsFixed(5) ?? '--';
          _lastSpeed = location['speed'] != null
              ? (location['speed'] * 3.6).toStringAsFixed(1)
              : '--';
          _lastTime = location['timestamp'] != null
              ? _formatDateTime(
                  DateTime.fromMillisecondsSinceEpoch(location['timestamp']),
                )
              : '--';
        });
      }
    });
  }

  String _formatDateTime(DateTime dt) {
    return '${dt.year}-${dt.month.toString().padLeft(2, '0')}-${dt.day.toString().padLeft(2, '0')} '
        '${dt.hour.toString().padLeft(2, '0')}:${dt.minute.toString().padLeft(2, '0')}:${dt.second.toString().padLeft(2, '0')}';
  }

  Future<void> _toggleTracking() async {
    final previousState = _isTracking;
    final newState = !_isTracking;

    setState(() => _isTracking = newState);

    bool success;
    if (newState) {
      success = await LocationBridge.startTracking(
        config: {
          'serverUrl': Preferences.serverUrl,
          'deviceId': Preferences.deviceId,
          'password': Preferences.password,
          'accuracy': Preferences.accuracy,
          'distanceFilter': Preferences.distanceFilter,
          'interval': Preferences.interval,
          'heartbeat': Preferences.heartbeat,
          'offlineBuffer': Preferences.offlineBuffer,
          'stopDetection': Preferences.stopDetection,
        },
      );
    } else {
      success = await LocationBridge.stopTracking();
    }

    if (!success && mounted) {
      setState(() => _isTracking = previousState);
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text(
            previousState
                ? 'Failed to stop tracking'
                : 'Failed to start tracking',
          ),
          backgroundColor: const Color(0xFF1a1a1a),
        ),
      );
    }
  }

  // ─── BUILD ────────────────────────────────────────────────────────────────

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: const Color(0xFF0d0d0d),
      body: SafeArea(
        child: Column(
          children: [
            _buildHeader(),
            Expanded(
              child: SingleChildScrollView(
                padding: const EdgeInsets.symmetric(horizontal: 20),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.stretch,
                  children: [
                    const SizedBox(height: 16),
                    _buildStatusCard(),
                    const SizedBox(height: 16),
                    _buildTrackingToggle(),
                    const SizedBox(height: 12),
                    _buildSendButton(),
                    const SizedBox(height: 12),
                    _buildNavButtons(),
                    const SizedBox(height: 20),
                  ],
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildHeader() {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 16),
      decoration: const BoxDecoration(
        color: Color(0xFF161616),
        border: Border(bottom: BorderSide(color: Color(0xFF2a2a2a), width: 1)),
      ),
      child: Row(
        children: [
          Container(
            width: 10,
            height: 10,
            decoration: BoxDecoration(
              shape: BoxShape.circle,
              color: _isTracking
                  ? const Color(0xFF00e676)
                  : const Color(0xFF616161),
              boxShadow: _isTracking
                  ? [
                      BoxShadow(
                        color: const Color(0xFF00e676).withValues(alpha: 0.6),
                        blurRadius: 8,
                        spreadRadius: 2,
                      ),
                    ]
                  : null,
            ),
          ),
          const SizedBox(width: 12),
          const Text(
            'TracPulse',
            style: TextStyle(
              fontFamily: 'monospace',
              fontSize: 18,
              fontWeight: FontWeight.w700,
              letterSpacing: 3,
              color: Color(0xFFe0e0e0),
            ),
          ),
          const Spacer(),
          Text(
            _isTracking ? 'ACTIVE' : 'IDLE',
            style: TextStyle(
              fontFamily: 'monospace',
              fontSize: 12,
              fontWeight: FontWeight.w700,
              letterSpacing: 2,
              color: _isTracking
                  ? const Color(0xFF00e676)
                  : const Color(0xFF616161),
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildStatusCard() {
    return Container(
      width: double.infinity,
      padding: const EdgeInsets.all(20),
      decoration: BoxDecoration(
        color: const Color(0xFF161616),
        borderRadius: BorderRadius.circular(4),
        border: Border.all(color: const Color(0xFF2a2a2a), width: 1),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            children: [
              const Icon(Icons.gps_fixed, size: 14, color: Color(0xFF00bcd4)),
              const SizedBox(width: 8),
              Text(
                'COORDINATES',
                style: TextStyle(
                  fontFamily: 'monospace',
                  fontSize: 11,
                  fontWeight: FontWeight.w700,
                  letterSpacing: 2,
                  color: const Color(0xFF00bcd4).withValues(alpha: 0.8),
                ),
              ),
            ],
          ),
          const SizedBox(height: 16),
          _buildCoordRow('LAT', _lastLat, const Color(0xFF69f0ae)),
          const SizedBox(height: 10),
          _buildCoordRow('LON', _lastLon, const Color(0xFF69f0ae)),
          const SizedBox(height: 18),
          Container(height: 1, color: const Color(0xFF2a2a2a)),
          const SizedBox(height: 18),
          _buildCoordRow('SPD', _lastSpeed, const Color(0xFFff9800)),
          const SizedBox(height: 10),
          _buildCoordRow('TIM', _lastTime, const Color(0xFF9e9e9e)),
        ],
      ),
    );
  }

  Widget _buildCoordRow(String label, String value, Color valueColor) {
    return Row(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        SizedBox(
          width: 36,
          child: Text(
            label,
            style: const TextStyle(
              fontFamily: 'monospace',
              fontSize: 11,
              fontWeight: FontWeight.w700,
              letterSpacing: 1,
              color: Color(0xFF616161),
            ),
          ),
        ),
        Expanded(
          child: Text(
            value,
            style: TextStyle(
              fontFamily: 'monospace',
              fontSize: 16,
              fontWeight: FontWeight.w400,
              letterSpacing: 1,
              color: valueColor,
            ),
          ),
        ),
      ],
    );
  }

  Widget _buildTrackingToggle() {
    return AnimatedBuilder(
      animation: _pulseAnimation,
      builder: (context, child) {
        return GestureDetector(
          onTap: _toggleTracking,
          child: Container(
            width: double.infinity,
            padding: const EdgeInsets.symmetric(vertical: 18, horizontal: 20),
            decoration: BoxDecoration(
              color: _isTracking
                  ? Color.lerp(
                      const Color(0xFF1b5e20),
                      const Color(0xFF2e7d32),
                      _pulseAnimation.value,
                    )
                  : const Color(0xFF1a1a1a),
              borderRadius: BorderRadius.circular(4),
              border: Border.all(
                color: _isTracking
                    ? const Color(0xFF00e676)
                    : const Color(0xFF2a2a2a),
                width: 1.5,
              ),
              boxShadow: _isTracking
                  ? [
                      BoxShadow(
                        color: const Color(
                          0xFF00e676,
                        ).withValues(alpha: 0.15 * _pulseAnimation.value),
                        blurRadius: 12,
                        spreadRadius: 0,
                      ),
                    ]
                  : null,
            ),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Icon(
                  _isTracking
                      ? Icons.radio_button_checked
                      : Icons.radio_button_off,
                  color: _isTracking
                      ? const Color(0xFF00e676)
                      : const Color(0xFF616161),
                  size: 20,
                ),
                const SizedBox(width: 12),
                Text(
                  _isTracking ? 'TRACKING ACTIVE' : 'START TRACKING',
                  style: TextStyle(
                    fontFamily: 'monospace',
                    fontSize: 14,
                    fontWeight: FontWeight.w700,
                    letterSpacing: 2,
                    color: _isTracking
                        ? const Color(0xFF00e676)
                        : const Color(0xFF9e9e9e),
                  ),
                ),
              ],
            ),
          ),
        );
      },
    );
  }

  Widget _buildSendButton() {
    if (!_isTracking) return const SizedBox.shrink();
    return SizedBox(
      height: 44,
      child: OutlinedButton.icon(
        onPressed: () async {
          final success = await LocationBridge.reportLocation();
          if (mounted) {
            ScaffoldMessenger.of(context).showSnackBar(
              SnackBar(
                content: Text(
                  success ? 'Location sent to server' : 'Failed — check logs',
                ),
                backgroundColor: const Color(0xFF1a1a1a),
              ),
            );
          }
        },
        style: OutlinedButton.styleFrom(
          foregroundColor: const Color(0xFF00bcd4),
          side: const BorderSide(color: Color(0xFF00bcd4), width: 1),
          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(4)),
        ),
        icon: const Icon(Icons.arrow_upward, size: 16),
        label: const Text(
          'SEND LOCATION',
          style: TextStyle(
            fontFamily: 'monospace',
            letterSpacing: 1,
            fontSize: 13,
          ),
        ),
      ),
    );
  }

  Widget _buildNavButtons() {
    return Row(
      children: [
        Expanded(
          child: _buildNavButton(
            icon: Icons.tune,
            label: 'SETTINGS',
            onTap: () => Navigator.push(
              context,
              MaterialPageRoute(builder: (_) => const SettingsScreen()),
            ),
          ),
        ),
        const SizedBox(width: 12),
        Expanded(
          child: _buildNavButton(
            icon: Icons.terminal,
            label: 'LOGS',
            onTap: () => Navigator.push(
              context,
              MaterialPageRoute(builder: (_) => const StatusScreen()),
            ),
          ),
        ),
      ],
    );
  }

  Widget _buildNavButton({
    required IconData icon,
    required String label,
    required VoidCallback onTap,
  }) {
    return Material(
      color: const Color(0xFF161616),
      borderRadius: BorderRadius.circular(4),
      child: InkWell(
        onTap: onTap,
        borderRadius: BorderRadius.circular(4),
        child: Container(
          padding: const EdgeInsets.symmetric(vertical: 14),
          decoration: BoxDecoration(
            borderRadius: BorderRadius.circular(4),
            border: Border.all(color: const Color(0xFF2a2a2a), width: 1),
          ),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Icon(icon, size: 16, color: const Color(0xFF757575)),
              const SizedBox(width: 8),
              Text(
                label,
                style: const TextStyle(
                  fontFamily: 'monospace',
                  fontSize: 12,
                  fontWeight: FontWeight.w700,
                  letterSpacing: 2,
                  color: Color(0xFF9e9e9e),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}