import 'package:flutter/material.dart';

class DurationPicker extends StatefulWidget {
  const DurationPicker({
    super.key,
    required this.onChangedCallback,
    required this.width,
    required this.height,
    this.initialDuration = const Duration(),
  });

  final void Function(Duration duration) onChangedCallback;
  final double width;
  final double height;
  final Duration initialDuration;

  @override
  State<DurationPicker> createState() => _DurationPickerState();
}

class _DurationPickerState extends State<DurationPicker> {
  String _timeString = '';

  @override
  void initState() {
    super.initState();
    if (widget.initialDuration.inMinutes != 0) {
      _timeString =
          '${widget.initialDuration.inHours}${widget.initialDuration.inMinutes % 60}';
    }
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        SizedBox(
          width: widget.width,
          height: widget.height / 4,
          child: Row(
            mainAxisSize: MainAxisSize.max,
            mainAxisAlignment: MainAxisAlignment.center,
            crossAxisAlignment: CrossAxisAlignment.end,
            children: [
              Text(
                _timeString.padLeft(4, '0').substring(0, 2),
                style: Theme.of(context).textTheme.displayMedium,
              ),
              Padding(padding: EdgeInsets.only(left: 5)),
              Text(
                'h',
                style:
                    Theme.of(context).textTheme.bodyLarge!.copyWith(height: 2),
              ),
              Padding(padding: EdgeInsets.only(left: 10)),
              Text(
                _timeString.padLeft(4, '0').substring(2, 4),
                style: Theme.of(context).textTheme.displayMedium,
              ),
              Padding(padding: EdgeInsets.only(left: 5)),
              Text(
                'm',
                style:
                    Theme.of(context).textTheme.bodyLarge!.copyWith(height: 2),
              ),
            ],
          ),
        ),
        Padding(padding: EdgeInsets.only(top: 10)),
        Row(
          mainAxisSize: MainAxisSize.max,
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(7),
                  child: Text('7'),
                ),
              ),
            ),
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(8),
                  child: Text('8'),
                ),
              ),
            ),
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(9),
                  child: Text('9'),
                ),
              ),
            ),
          ],
        ),
        Row(
          mainAxisSize: MainAxisSize.max,
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(4),
                  child: Text('4'),
                ),
              ),
            ),
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(5),
                  child: Text('5'),
                ),
              ),
            ),
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(6),
                  child: Text('6'),
                ),
              ),
            ),
          ],
        ),
        Row(
          mainAxisSize: MainAxisSize.max,
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(1),
                  child: Text('1'),
                ),
              ),
            ),
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(2),
                  child: Text('2'),
                ),
              ),
            ),
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(3),
                  child: Text('3'),
                ),
              ),
            ),
          ],
        ),
        Row(
          mainAxisSize: MainAxisSize.max,
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(padding: EdgeInsets.all(0)),
            ),
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: () => _addTime(0),
                  child: Text('0'),
                ),
              ),
            ),
            SizedBox(
              width: widget.width / 3,
              height: widget.height / 4,
              child: Padding(
                padding: const EdgeInsets.fromLTRB(8, 0, 8, 8),
                child: ElevatedButton(
                  style: _buttonTheme,
                  onPressed: _removeTime,
                  child: Icon(
                    Icons.backspace,
                    size: 24,
                  ),
                ),
              ),
            ),
          ],
        ),
      ],
    );
  }

  void _addTime(int time) {
    if (_timeString.length >= 4) return;
    if (_timeString.isEmpty && time == 0) return;

    setState(() {
      _timeString += time.toString();
    });

    widget.onChangedCallback(_duration);
  }

  void _removeTime() {
    if (_timeString.isEmpty) return;
    setState(() {
      _timeString = _timeString.substring(0, _timeString.length - 1);
    });

    widget.onChangedCallback(_duration);
  }

  Duration get _duration {
    return Duration(
      hours: int.parse(_timeString.padLeft(4, '0').substring(0, 2)),
      minutes: int.parse(_timeString.padLeft(4, '0').substring(2, 4)),
    );
  }

  ButtonStyle get _buttonTheme => ElevatedButton.styleFrom(
        textStyle: Theme.of(context).textTheme.displaySmall,
      );
}