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

import '../../../utils/definitions/ColorPairs.dart';
import '../../../utils/logic/PreferencesService.dart'; // Correct the path as necessary

class CalendarWidget extends StatefulWidget {
  final DateTime currentDate;

  CalendarWidget({Key? key, required this.currentDate}) : super(key: key);

  @override
  _CalendarWidgetState createState() => _CalendarWidgetState();
}

class _CalendarWidgetState extends State<CalendarWidget> {
  List<DateTime> dateList = []; // Initialized immediately as an empty list
  Map<String, DiaryEntry?> diaryEntries = {}; // Holds diary entries by date
  late ColorPair currentColorPair; // Holds the current color pair

  @override
  void initState() {
    super.initState();
    dateList = _generateDateList(widget.currentDate); // Ensured initialization
    _loadColorPairAndDiaryData();
  }

  void _loadColorPairAndDiaryData() async {
    // Load color pair
    currentColorPair =
        await PreferencesService().loadColorPair() ?? colorPairs[0];

    // Generate date list
    //dateList = _generateDateList(widget.currentDate);

    // Load diary entries for each date
    for (DateTime date in dateList) {
      DiaryEntry? entry = await PreferencesService().getDiaryEntryByDate(date);
      String key = DateFormat('yyyy-MM-dd').format(date);
      diaryEntries[key] = entry;
    }
    setState(() {}); // Update the state to reflect new data
  }

  List<DateTime> _generateDateList(DateTime date) {
    List<DateTime> list = [];
    DateTime firstOfMonth = DateTime(date.year, date.month, 1);
    int dayOfWeek = firstOfMonth.weekday;

    // Adjust to Monday start
    int startDay = dayOfWeek - 1;
    if (startDay < 0) startDay = 6;

    // Dates from previous month
    for (int i = startDay; i > 0; i--) {
      list.add(firstOfMonth.subtract(Duration(days: i)));
    }

    // Dates of current month
    int daysInMonth = DateUtils.getDaysInMonth(date.year, date.month);
    for (int i = 0; i < daysInMonth; i++) {
      list.add(DateTime(date.year, date.month, i + 1));
    }

    // Adjust list to end with a complete week
    while (list.length % 7 != 0) {
      list.add(list.last.add(Duration(days: 1)));
    }

    return list;
  }

  @override
  Widget build(BuildContext context) {
    double addon = dateList.length > 35 ? 50 : 0;
    String monthName =
        DateFormat("MMMM yyyy").format(widget.currentDate); // For month header

    return FutureBuilder<ColorPair>(
        future: PreferencesService().loadColorPair(),
        builder: (context, snapshot) {
          if (!snapshot.hasData) {
            return Center(child: CircularProgressIndicator());
          }
          ColorPair colorPair = snapshot.data!;

          return Container(
            height: 360 + addon,
            child: Column(
              children: [
                Padding(
                  padding: EdgeInsets.symmetric(vertical: 8.0),
                  child: Text(monthName,
                      style: TextStyle(
                          fontSize: 20,
                          fontWeight: FontWeight.bold)), // Month Header
                ),
                Expanded(
                  child: Padding(
                    padding: const EdgeInsets.fromLTRB(25, 0, 25, 0),
                    child: GridView.builder(
                      physics: NeverScrollableScrollPhysics(),
                      gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
                        crossAxisCount: 7,
                      ),
                      itemBuilder: (context, index) {
                        DateTime date = dateList[index];
                        bool isCurrentMonth =
                            date.month == widget.currentDate.month;
                        double opacity = isCurrentMonth ? 1.0 : 0.15;

                        // Fetching diary entry percentage value
                        DiaryEntry? entry =
                            diaryEntries[DateFormat('yyyy-MM-dd').format(date)];
                        double fillPercentage =
                            entry != null ? entry.percentValue / 100.0 : 0.0;

                        return Center(
                          child: GestureDetector(
                            onTap: () => {context.go('/entry', extra: date)},
                            child: Container(
                              width: 50,
                              height: 50,
                              decoration: BoxDecoration(
                                shape: BoxShape.circle,
                                border:
                                    Border.all(color: Colors.black, width: 2),
                                color: DateTime.now().day == date.day &&
                                        DateTime.now().month == date.month &&
                                        DateTime.now().year == date.year
                                    ? Colors
                                        .orange // Setting background color for current day
                                    : isCurrentMonth
                                        ? Colors.transparent
                                        : Colors.grey.withOpacity(opacity),
                              ),
                              child: Stack(
                                alignment: Alignment.center,
                                children: [
                                  CircleWidget(
                                      radius: 25 * fillPercentage,
                                      color: fillPercentage > 0
                                          ? colorPair.backgroundColor
                                          : Colors.teal.withOpacity(opacity)),
                                  Text(
                                    DateFormat("d").format(date),
                                    style: TextStyle(color: Colors.black),
                                  ),
                                ],
                              ),
                            ),
                          ),
                        );
                      },
                      itemCount: dateList.length,
                    ),
                  ),
                ),
              ],
            ),
          );
        });
  }

  Widget _buildDateCell(DateTime date, DiaryEntry? entry) {
    bool isCurrentMonth = date.month == widget.currentDate.month;
    double opacity = isCurrentMonth ? 1.0 : 0.5;
    Color bgColor = entry != null
        ? currentColorPair.backgroundColor.withOpacity(opacity)
        : Colors.transparent;
    double fillPercentage = entry != null
        ? entry.percentValue / 100
        : 0; // Assuming percentValue is 0-100

    return GestureDetector(
      onTap: () {
        context.go('/entry', extra: date);
      },
      child: Container(
        // ... existing decoration adjusted for opacity ...
        child: Stack(
          alignment: Alignment.center,
          children: [
            // Inner circle representing diary entry value
            CircleWidget(
                radius: 25 * fillPercentage, // Adjust radius based on value
                color: fillPercentage > 0
                    ? currentColorPair.backgroundColor
                    : Colors.grey.withOpacity(opacity)),
            Text(
              DateFormat("d").format(date),
              style: TextStyle(color: Colors.black),
            ),
          ],
        ),
      ),
    );
  }
}

class CircleWidget extends StatelessWidget {
  final double radius;
  final Color color;

  CircleWidget({Key? key, required this.radius, required this.color})
      : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Container(
      width: radius * 2,
      height: radius * 2,
      decoration: BoxDecoration(
        shape: BoxShape.circle,
        color: color,
      ),
    );
  }
}