import 'package:period_date_flutter/period_date_flutter.dart';

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Period Date Picker')),
      body: Padding(
        padding: EdgeInsets.all(16.0),
        child: PeriodDatePicker(
          onChanged: (PeriodDateRange range) {
            print('Selected range: ${range.startDate} to ${range.endDate}');
            print('Type: ${range.type}');
            print('Valid: ${range.isValid}');
          },
        ),
      ),
    );
  }
}

PeriodDatePicker(
  initialType: PeriodDateType.week,
  initialStartDate: DateTime(2024, 1, 1),
  initialEndDate: DateTime(2024, 1, 7),
  firstDate: DateTime(2020),
  lastDate: DateTime(2030),
  title: Text(
    'Select Period',
    style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
  ),
  hintText: 'Choose dates',
  onChanged: (PeriodDateRange range) {
    if (range.isValid) {
      // Handle valid date range
      _handleDateRange(range);
    }
  },
)

void _handleDateRange(PeriodDateRange range) {
  // Check if range is valid
  if (!range.isValid) {
    print('Invalid date range');
    return;
  }
  
  // Get duration
  final Duration? duration = range.duration;
  if (duration != null) {
    print('Duration: ${duration.inDays} days');
  }
  
  // Create a copy with modifications
  final PeriodDateRange newRange = range.copyWith(
    type: PeriodDateType.month,
  );
  
  // Access individual properties
  print('Start: ${range.startDate}');
  print('End: ${range.endDate}');
  print('Type: ${range.type}');
}

// Day selection
PeriodDatePicker(
  initialType: PeriodDateType.day,
  onChanged: (range) {
    if (range.type == PeriodDateType.day) {
      print('Selected ${range.duration?.inDays} days');
    }
  },
)

// Week selection
PeriodDatePicker(
  initialType: PeriodDateType.week,
  onChanged: (range) {
    if (range.type == PeriodDateType.week) {
      final weeks = (range.duration?.inDays ?? 0) / 7;
      print('Selected ${weeks.ceil()} weeks');
    }
  },
)

// Month selection
PeriodDatePicker(
  initialType: PeriodDateType.month,
  onChanged: (range) {
    if (range.type == PeriodDateType.month) {
      final months = _calculateMonths(range.startDate!, range.endDate!);
      print('Selected $months months');
    }
  },
)

enum PeriodDateType {
  day,    // Select by days
  week,   // Select by weeks
  month,  // Select by months
}

class PeriodDateRange {
  final DateTime? startDate;    // Start date of the range
  final DateTime? endDate;      // End date of the range
  final PeriodDateType type;    // Type of period selection
  
  bool get isValid;             // Check if range is valid
  Duration? get duration;       // Get duration of the range
  
  PeriodDateRange copyWith({    // Create a copy with modifications
    DateTime? startDate,
    DateTime? endDate,
    PeriodDateType? type,
  });
}

class PeriodDatePicker extends StatefulWidget {
  final PeriodDateType initialType;      // Initial period type
  final DateTime? initialStartDate;      // Initial start date
  final DateTime? initialEndDate;        // Initial end date
  final DateTime? firstDate;             // Earliest selectable date
  final DateTime? lastDate;              // Latest selectable date
  final Function(PeriodDateRange)? onChanged; // Callback for changes
  final Widget? title;                   // Optional title widget
  final String? hintText;                // Hint text for date inputs
}