didvan-app/lib/views/notification_time/widgets/custom_cupertino_date_picker.dart

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

import '../../../models/day_time.dart';
import '../../../utils/date_time.dart';

class CustomCupertinoDatePicker extends StatefulWidget {
  final double itemExtent;
  final void Function(DayTime)
      onSelectedItemChanged; // Text style of selected item
  final TextStyle? selectedStyle; // Text style of unselected item
  final TextStyle? unselectedStyle; // Text style of disabled item
  final TextStyle? disabledStyle; // Minimum selectable date
  final DayTime? selectedTime;
  final bool disable;

  const CustomCupertinoDatePicker({
    Key? key,
    required this.itemExtent,
    required this.onSelectedItemChanged,
    this.selectedTime,
    this.selectedStyle,
    this.unselectedStyle,
    this.disabledStyle,
    this.disable = false,
  }) : super(key: key);

  @override
  State<CustomCupertinoDatePicker> createState() =>
      _CustomCupertinoDatePickerState();
}

class _CustomCupertinoDatePickerState extends State<CustomCupertinoDatePicker> {
  late DayTime selectedTime = DateTimeUtils.handleDayTime(
      "${DateTime.now().hour.toString()}:${DateTime.now().minute.toString()}");

  late int _selectedMeridiemIndex;
  late int _selectedHourIndex;
  late int _selectedMinuteIndex;

  late final FixedExtentScrollController _meridiemScrollController;
  late final FixedExtentScrollController _hourScrollController;
  late final FixedExtentScrollController _minuteScrollController;

  final _meridiem = [
    'قبل از ظهر',
    'بعد از ظهر',
  ];

  final _timeH = [];

  final _timeM = [];

  @override
  void initState() {
    super.initState();

    for (int i = 1; i < 12 + 1; i++) {
      String twoDigitNumber = i.toString().padLeft(2, '0');
      _timeH.add(twoDigitNumber);
    }
    for (int i = 1; i < 12 + 1; i++) {
      String twoDigitNumber = i.toString().padLeft(2, '0');
      _timeH.add(twoDigitNumber);
    }
    for (int i = 0; i < 59 + 1; i++) {
      String twoDigitNumber = i.toString().padLeft(2, '0');
      _timeM.add(twoDigitNumber);
    }
    _meridiemScrollController = FixedExtentScrollController();
    _hourScrollController = FixedExtentScrollController();
    _minuteScrollController = FixedExtentScrollController();
    if (widget.selectedTime != null) {
      selectedTime = widget.selectedTime!;
    }
    _initDates();
  }

  void _initDates() {
    _selectedMeridiemIndex = 0;

    switch (selectedTime.meridiem) {
      case Meridiem.AM:
        _selectedMeridiemIndex = 0;
        _selectedHourIndex = int.parse(selectedTime.hour) - 1;

        break;

      case Meridiem.PM:
        _selectedMeridiemIndex = 1;
        _selectedHourIndex = (int.parse(selectedTime.hour) + 12) - 1;

        break;
    }
    _selectedMinuteIndex = int.parse(selectedTime.minute);
    WidgetsBinding.instance.addPostFrameCallback((_) {
      _scrollList(_meridiemScrollController, _selectedMeridiemIndex);
      _scrollList(_hourScrollController, _selectedHourIndex);
      _scrollList(_minuteScrollController, _selectedMinuteIndex);
    });
  }

  void _scrollList(FixedExtentScrollController controller, int index) {
    controller.animateToItem(
      index,
      curve: Curves.easeIn,
      duration: const Duration(milliseconds: 300),
    );
  }

  @override
  void dispose() {
    _meridiemScrollController.dispose();
    _hourScrollController.dispose();
    _minuteScrollController.dispose();
    super.dispose();
  }

  void _onSelectedItemChanged(int index, SelectorType type) {
    switch (type) {
      case SelectorType.meridiem:
        _selectedMeridiemIndex = index; // if month is changed to february &
        if (_selectedMeridiemIndex == 0) {
          if (_selectedHourIndex > 12 - 1) {
            _selectedHourIndex -= 12;
            _hourScrollController.jumpToItem(_selectedHourIndex);
          }
        } else {
          if (_selectedHourIndex < 12 - 1) {
            _selectedHourIndex += 12;
            _hourScrollController.jumpToItem(_selectedHourIndex);
          }
        }
        if (index == 0) {
          selectedTime.meridiem = Meridiem.AM;
        } else {
          selectedTime.meridiem = Meridiem.PM;
        }
        break;

      case SelectorType.hour:
        _selectedHourIndex = index; // if month is changed to february &
        if (_selectedHourIndex > 12 - 1) {
          _selectedMeridiemIndex = 1;
          _meridiemScrollController.jumpToItem(_selectedMeridiemIndex);
        } else {
          _selectedMeridiemIndex = 0;
          _meridiemScrollController.jumpToItem(_selectedMeridiemIndex);
        }
        selectedTime.hour = _timeH[index];

        break;

      case SelectorType.minute:
        _selectedMinuteIndex = index;
        selectedTime.minute = _timeM[index];

        break;
    }

    setState(() {});
    widget.onSelectedItemChanged(selectedTime);
  }

  /// check if the given day, month or year index is disabled
  bool _isDisabled(int index, SelectorType type) {
    // switch (type) {
    //   case SelectorType.meridiem:
    //     break;
    //
    //   case SelectorType.hour:
    //     break;
    //
    //   case SelectorType.minute:
    //     break;
    // }
    return false;
  }

  @override
  Widget build(BuildContext context) {
    Color shadow = Theme.of(context).colorScheme.background;
    return IgnorePointer(
      ignoring: widget.disable,
      child: Stack(
        children: [
          Positioned.fill(
            child: Center(
              child: Container(
                height: 64,
                decoration: BoxDecoration(
                    color: Theme.of(context).colorScheme.primary.withOpacity(widget.disable? 0.2: 1),
                    borderRadius: BorderRadius.circular(18)),
                child: const Padding(
                  padding: EdgeInsets.symmetric(vertical: 12),
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.spaceAround,
                    children: [
                      SizedBox(),
                      VerticalDivider(
                        color: Colors.white,
                      ),
                      VerticalDivider(
                        color: Colors.white,
                      ),
                      SizedBox(),
                    ],
                  ),
                ),
              ),
            ),
          ),
          Row(
            children: [
              Expanded(child: _meridiemSelector()),
              Expanded(child: _minuteSelector()),
              Expanded(child: _hourSelector()),
            ],
          ),
          Positioned(
              top: 0,
              left: 0,
              right: 0,
              child: Container(
                height: 32,
                decoration: BoxDecoration(
                    gradient: LinearGradient(
                        begin: Alignment.topCenter,
                        end: Alignment.bottomCenter,
                        colors: [
                      shadow.withOpacity(1),
                      shadow.withOpacity(0.9),
                      shadow.withOpacity(0.8),
                      shadow.withOpacity(0.6),
                      shadow.withOpacity(0.5),
                      shadow.withOpacity(0.4),
                    ])),
              )),
          Positioned(
              bottom: 0,
              left: 0,
              right: 0,
              child: Container(
                height: 32,
                decoration: BoxDecoration(
                    gradient: LinearGradient(
                        begin: Alignment.bottomCenter,
                        end: Alignment.topCenter,
                        colors: [
                      shadow.withOpacity(1),
                      shadow.withOpacity(0.9),
                      shadow.withOpacity(0.8),
                      shadow.withOpacity(0.6),
                      shadow.withOpacity(0.5),
                      shadow.withOpacity(0.4),
                    ])),
              )),
        ],
      ),
    );
  }

  Widget _selector({
    required List<dynamic> values,
    required int selectedValueIndex,
    required bool Function(int) isDisabled,
    required void Function(int) onSelectedItemChanged,
    required FixedExtentScrollController scrollController,
  }) {
    return CupertinoPicker.builder(
      childCount: values.length,
      itemExtent: widget.itemExtent,
      scrollController: scrollController,
      squeeze: 1.45,
      useMagnifier: false,
      diameterRatio: 2.3,
      magnification: 1.0,
      offAxisFraction: 0.0,
      selectionOverlay: const SizedBox(),
      onSelectedItemChanged: onSelectedItemChanged,
      itemBuilder: (context, index) => Container(
        height: widget.itemExtent,
        alignment: Alignment.center,
        decoration: const BoxDecoration(),
        child: Text(
          '${values[index]}',
          style: index == selectedValueIndex
              ? widget.selectedStyle
              : isDisabled(index)
                  ? widget.disabledStyle
                  : widget.unselectedStyle,
        ),
      ),
    );
  }

  Widget _meridiemSelector() {
    return _selector(
      values: _meridiem,
      selectedValueIndex: _selectedMeridiemIndex,
      scrollController: _meridiemScrollController,
      isDisabled: (index) => _isDisabled(index, SelectorType.meridiem),
      onSelectedItemChanged: (v) => _onSelectedItemChanged(
        v,
        SelectorType.meridiem,
      ),
    );
  }

  Widget _hourSelector() {
    return _selector(
      values: _timeH,
      selectedValueIndex: _selectedHourIndex,
      scrollController: _hourScrollController,
      isDisabled: (index) => _isDisabled(index, SelectorType.hour),
      onSelectedItemChanged: (v) => _onSelectedItemChanged(
        v,
        SelectorType.hour,
      ),
    );
  }

  Widget _minuteSelector() {
    return _selector(
      values: _timeM,
      selectedValueIndex: _selectedMinuteIndex,
      scrollController: _minuteScrollController,
      isDisabled: (index) => _isDisabled(index, SelectorType.minute),
      onSelectedItemChanged: (v) => _onSelectedItemChanged(
        v,
        SelectorType.minute,
      ),
    );
  }
}