palmoil-mobile/lib/widgets/class_picker_sheet.dart

import 'package:flutter/material.dart';
import '../constants/mpob_colors.dart';

/// Result of [showClassPickerSheet]: either a picked [className], or
/// [remove] set when the harvester chose to delete the detection entirely.
class ClassPickResult {
  final String? className;
  final bool remove;

  const ClassPickResult({this.className, this.remove = false});
}

/// Shared MPOB class-picker bottom sheet, used both to correct an existing
/// detection's grade and to grade a newly-added one.
Future<ClassPickResult?> showClassPickerSheet(
  BuildContext context, {
  required String? currentClass,
  bool showRemoveOption = false,
}) {
  final colorScheme = Theme.of(context).colorScheme;
  return showModalBottomSheet<ClassPickResult>(
    context: context,
    shape: const RoundedRectangleBorder(borderRadius: BorderRadius.vertical(top: Radius.circular(20))),
    builder: (sheetContext) {
      return SafeArea(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Padding(
              padding: const EdgeInsets.fromLTRB(20, 20, 20, 8),
              child: Align(
                alignment: Alignment.centerLeft,
                child: Text("Correct Grade", style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold, color: colorScheme.onSurface)),
              ),
            ),
            ...mpobClasses.map((className) {
              return ListTile(
                leading: Container(width: 14, height: 14, decoration: BoxDecoration(color: getMPOBColor(className), shape: BoxShape.circle)),
                title: Text(className),
                trailing: currentClass == className ? const Icon(Icons.check) : null,
                onTap: () => Navigator.pop(sheetContext, ClassPickResult(className: className)),
              );
            }),
            if (showRemoveOption) ...[
              const Divider(height: 1),
              ListTile(
                leading: Icon(Icons.delete_outline, color: colorScheme.error),
                title: Text("Remove this detection", style: TextStyle(color: colorScheme.error)),
                onTap: () => Navigator.pop(sheetContext, const ClassPickResult(remove: true)),
              ),
            ],
            const SizedBox(height: 8),
          ],
        ),
      );
    },
  );
}