import 'package:wanisclient/utils/colors.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:intl/intl.dart';

class monthGrid extends StatelessWidget {
  final DateTime monthStart;
  final DateTime selected;
  final ValueChanged<DateTime> onSelect;

  const monthGrid({
    required this.monthStart,
    required this.selected,
    required this.onSelect,
  });

  @override
  Widget build(BuildContext context) {
    final daysInMonth = DateUtils.getDaysInMonth(monthStart.year, monthStart.month);
    final firstWeekday = _mondayFirstOffset(monthStart);
    final totalCells = firstWeekday + daysInMonth;
    final rows = (totalCells / 7).ceil();
    final now = DateTime.now();
    final today = DateTime(now.year, now.month, now.day);

    return Padding(
      padding: const EdgeInsets.only(bottom: 12),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          // month title
          Padding(
            padding: const EdgeInsets.symmetric(vertical: 8),
            child: Text(
              DateFormat('MMMM').format(monthStart),
              style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w600, color: Colors.black87),
            ),
          ),
          // grid
          LayoutBuilder(
            builder: (context, c) {
              final cellW = (c.maxWidth) / 7;
              final cellH = cellW * .9;
              return Column(
                children: List.generate(rows, (r) {
                  return Row(
                    children: List.generate(7, (col) {
                      final idx = r * 7 + col;
                      final dayNum = idx - firstWeekday + 1;
                      DateTime? date;
                      bool enabled = false;
                      if (dayNum >= 1 && dayNum <= daysInMonth) {
                        date = DateTime(monthStart.year, monthStart.month, dayNum);
                        enabled = !date.isBefore(today);
                      }
                      final isSelected = date != null &&
                          date.year == selected.year &&
                          date.month == selected.month &&
                          date.day == selected.day;

                      return SizedBox(
                        width: cellW,
                        height: cellH,
                        child: Center(
                          child: date == null
                              ? const SizedBox.shrink()
                              : InkWell(
                            borderRadius: BorderRadius.circular(20),
                            onTap: enabled ? () => onSelect(date!) : null,
                            child: Container(
                              width: 34,
                              height: 34,
                              decoration: BoxDecoration(
                                color: isSelected
                                    ? AppNewColors.primaryBtnColor
                                    : Colors.transparent,
                                borderRadius: BorderRadius.circular(18),
                              ),
                              alignment: Alignment.center,
                              child: Text(
                                '$dayNum',
                                style: TextStyle(
                                  fontSize: 14,
                                  fontWeight: FontWeight.w600,
                                  color: enabled
                                      ? (isSelected ? Colors.white : Colors.black87)
                                      : const Color(0xFFBDBDBD),
                                ),
                              ),
                            ),
                          ),
                        ),
                      );
                    }),
                  );
                }),
              );
            },
          ),
        ],
      ),
    );
  }

  // convert DateTime.weekday (Mon=1..Sun=7) to 0-based offset with Monday first
  int _mondayFirstOffset(DateTime firstOfMonth) {
    final w = firstOfMonth.weekday; // 1..7
    return (w + 6) % 7;
  }
}