eatvio_app/lib/features/diary/presentation/widgets/calendar_widget.dart

import 'package:eatvio_app/core/theme/theme_helper.dart';
import 'package:eatvio_app/core/widgets/show_error_dialog.dart';
import 'package:eatvio_app/features/diary/presentation/bloc/diary_cubit.dart';
import 'package:eatvio_app/features/diary/presentation/bloc/diary_state.dart';
import 'package:eatvio_app/generated/l10n.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:table_calendar/table_calendar.dart';

class CalendarWidget extends StatefulWidget {
  const CalendarWidget({super.key, this.date});
  final DateTime? date;

  @override
  State<CalendarWidget> createState() => _CalendarWidgetState();
}

class _CalendarWidgetState extends State<CalendarWidget> {
  static const _kDaysOfWeekHeight = 16.0;
  static const _kRowHeight = 52.0;

  CalendarFormat _calendarFormat = CalendarFormat.week;
  DateTime _focusedDay = DateTime.now();
  DateTime _selectedDay = DateTime.now();
  @override
  void initState() {
    super.initState();
    if (widget.date != null) {
      _selectedDay = widget.date!;
      _focusedDay = widget.date!;
    }
  }

  @override
  void didUpdateWidget(CalendarWidget oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (widget.date != null && widget.date != oldWidget.date) {
      _selectedDay = widget.date!;
      _focusedDay = widget.date!;
    }
  }

  @override
  Widget build(BuildContext context) {
    final s = S.of(context);
    final textScaler = MediaQuery.textScalerOf(context);
    final daysOfWeekHeight = _scaledDaysOfWeekHeight(context);
    return BlocConsumer<DiaryCubit, DiaryState>(
      listener: (BuildContext context, DiaryState state) {
        if (state is DiaryStateLoaded) {
          setState(() {
            _selectedDay = state.selectedDay;
          });
        }
      },
      builder: (BuildContext context, DiaryState state) {
        return Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Padding(
              padding: const EdgeInsets.only(top: 16),
              child: TableCalendar(
                focusedDay: _focusedDay,
                firstDay: DateTime.utc(2020, 10, 16),
                lastDay: DateTime.utc(2030, 3, 14),
                locale: 'ru_RU',
                startingDayOfWeek: StartingDayOfWeek.monday,
                calendarFormat: _calendarFormat,
                daysOfWeekHeight: daysOfWeekHeight,
                rowHeight: textScaler.scale(_kRowHeight),
                headerStyle: const HeaderStyle(titleCentered: true, formatButtonVisible: false, leftChevronVisible: false, rightChevronVisible: false),
                onDaySelected: (selectedDay, focusedDay) async {
                  if (!isSameDay(_selectedDay, selectedDay)) {
                    final previousSelectedDay = _selectedDay;
                    final previousFocusedDay = _selectedDay;
                    setState(() {
                      _selectedDay = selectedDay;
                      _focusedDay = focusedDay;
                    });
                    final canOpenNextDay = await context.read<DiaryCubit>().setSelectedDay(selectedDay);
                    if (!canOpenNextDay && context.mounted) {
                      showErrorDialog(context, title: s.want_to_see_tomorrow, description: s.can_not_see_next_day);
                      setState(() {
                        _selectedDay = previousSelectedDay;
                        _focusedDay = previousFocusedDay;
                      });
                      return;
                    }
                  }
                },
                selectedDayPredicate: (day) {
                  return isSameDay(_selectedDay, day);
                },
                onPageChanged: (focusedDay) {
                  setState(() {
                    _focusedDay = focusedDay;
                  });
                },
                onFormatChanged: (format) {
                  if (_calendarFormat != format) {
                    setState(() {
                      _calendarFormat = format;
                    });
                  }
                },
                calendarStyle: CalendarStyle(
                  weekendDecoration: const BoxDecoration(color: Colors.white, shape: BoxShape.circle),
                  defaultDecoration: const BoxDecoration(color: Colors.white, shape: BoxShape.circle),
                  selectedDecoration: BoxDecoration(color: appTheme.blueA400, shape: BoxShape.circle),
                  todayTextStyle: const TextStyle(color: Colors.black),
                  todayDecoration: BoxDecoration(
                    border: Border.all(color: appTheme.blueA400, width: 2),
                    color: Colors.white,
                    shape: BoxShape.circle,
                  ),
                ),
              ),
            ),
            _arrowDown(),
          ],
        );
      },
    );
  }

  double _scaledDaysOfWeekHeight(BuildContext context) {
    final painter = TextPainter(
      text: TextSpan(text: 'Щy', style: DefaultTextStyle.of(context).style),
      textDirection: Directionality.of(context),
      textScaler: MediaQuery.textScalerOf(context),
      maxLines: 1,
    )..layout();
    final height = painter.height;
    painter.dispose();
    return height.clamp(_kDaysOfWeekHeight, double.infinity);
  }

  void _nextCalendarFormat() {
    setState(() {
      _calendarFormat = CalendarFormat.values[(_calendarFormat.index - 1) % CalendarFormat.values.length];
    });
  }

  GestureDetector _arrowDown() {
    return GestureDetector(
      behavior: HitTestBehavior.translucent,
      onVerticalDragStart: (_) {
        _nextCalendarFormat();
      },
      onTap: () {
        _nextCalendarFormat();
      },
      child: Container(
        width: double.infinity,
        padding: const EdgeInsets.only(top: 8, bottom: 16),
        child: Icon(_calendarFormat == CalendarFormat.month ? Icons.keyboard_arrow_up_rounded : Icons.keyboard_arrow_down_rounded, color: Colors.grey.shade600),
      ),
    );
  }
}