import 'dart:async';
import 'dart:math' as math;

import 'package:flutter/material.dart';
import 'package:hive_flutter/hive_flutter.dart';
import 'package:intl/intl.dart';

import '../models/drink_type.dart';

class HydrationService extends ChangeNotifier {
  final Box _dataBox = Hive.box('hydrationData');
  final Box _settingsBox = Hive.box('userSettings');

  double _currentIntake = 0.0;
  double _purityScore = 1.0;
  DateTime _lastDrinkTime = DateTime.now();

  Map<DrinkType, double> _breakdown = {
    DrinkType.Water: 0,
    DrinkType.Coffee: 0,
    DrinkType.Tea: 0,
    DrinkType.Soda: 0,
  };

  double _weight = 60.0;
  double _workoutMinutes = 0.0;
  bool _remindersEnabled = true;
  double _reminderInterval = 60.0;

  List<double> _history = [];
  Timer? _decayTimer;

  HydrationService() {
    _loadData();
    _startDecayCheck();
  }

  double get currentIntake => _currentIntake;
  double get dailyGoal => (_weight * 35.0) + (_workoutMinutes * 8.0);
  double get percentage => (_currentIntake / dailyGoal).clamp(0.0, 1.0);
  List<double> get history => _history;
  double get weight => _weight;
  double get workoutMinutes => _workoutMinutes;
  bool get remindersEnabled => _remindersEnabled;
  double get reminderInterval => _reminderInterval;
  Map<DrinkType, double> get breakdown => _breakdown;

  Color get dynamicWaterColor {
    Color baseColor = const Color(0xFF00BFFF);
    Color impurityColor = const Color(0xFFD2B48C);
    Color blendedWithImpurity = Color.lerp(impurityColor, baseColor, _purityScore)!;

    final minutesSince = DateTime.now().difference(_lastDrinkTime).inMinutes;
    double freshness = 1.0;
    if (minutesSince > 120) {
      double overdueHours = (minutesSince - 120) / 60.0;
      freshness = (1.0 - (overdueHours * 0.2)).clamp(0.4, 1.0);
    }

    Color dryColor = Colors.grey.shade400;
    return Color.lerp(dryColor, blendedWithImpurity, freshness)!;
  }

  String get statusText {
    final minutesSince = DateTime.now().difference(_lastDrinkTime).inMinutes;
    if (minutesSince > 120) return "Body is withering...";
    if (_purityScore < 0.7) return "Purify your system";
    return "Metabolism Optimal";
  }

  void _loadData() {
    final todayKey = DateFormat('yyyyMMdd').format(DateTime.now());
    _currentIntake = _dataBox.get(todayKey, defaultValue: 0.0);

    _purityScore = _dataBox.get('purity_$todayKey', defaultValue: 1.0);
    int? lastTs = _dataBox.get('last_drink_ts');
    _lastDrinkTime = lastTs != null ? DateTime.fromMillisecondsSinceEpoch(lastTs) : DateTime.now();

    _weight = _settingsBox.get('weight', defaultValue: 60.0);
    _workoutMinutes = _settingsBox.get('workout', defaultValue: 0.0);
    _remindersEnabled = _settingsBox.get('reminders', defaultValue: true);
    _reminderInterval = _settingsBox.get('reminderInterval', defaultValue: 60.0);

    if (_history.isEmpty) {
      for (int i = 0; i < 7; i++) {
        _history.add(1500 + math.Random().nextInt(1500).toDouble());
      }
    }

    _breakdown = {
      DrinkType.Water: _currentIntake * 0.7,
      DrinkType.Coffee: _currentIntake * 0.2,
      DrinkType.Tea: _currentIntake * 0.1,
      DrinkType.Soda: 0,
    };
    notifyListeners();
  }

  void updateSettings({double? weight, double? workout, bool? reminders, double? interval}) {
    if (weight != null) _weight = weight;
    if (workout != null) _workoutMinutes = workout;
    if (reminders != null) _remindersEnabled = reminders;
    if (interval != null) _reminderInterval = interval;

    _settingsBox.put('weight', _weight);
    _settingsBox.put('workout', _workoutMinutes);
    _settingsBox.put('reminders', _remindersEnabled);
    _settingsBox.put('reminderInterval', _reminderInterval);
    notifyListeners();
  }

  void addWater(double amount, {DrinkType type = DrinkType.Water}) {
    double efficientAmount = amount * type.hydrationFactor;
    _currentIntake += efficientAmount;

    _breakdown[type] = (_breakdown[type] ?? 0) + efficientAmount;

    if (type == DrinkType.Water) {
      _purityScore = (_purityScore + 0.15).clamp(0.0, 1.0);
    } else {
      _purityScore = (_purityScore - (1.0 - type.purityFactor)).clamp(0.0, 1.0);
    }

    _lastDrinkTime = DateTime.now();

    final todayKey = DateFormat('yyyyMMdd').format(DateTime.now());
    _dataBox.put(todayKey, _currentIntake);
    _dataBox.put('purity_$todayKey', _purityScore);
    _dataBox.put('last_drink_ts', _lastDrinkTime.millisecondsSinceEpoch);

    notifyListeners();
  }

  void _startDecayCheck() {
    _decayTimer = Timer.periodic(const Duration(minutes: 1), (timer) {
      notifyListeners();
    });
  }

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