import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:intl/intl.dart';

import '../../../core/database/database.dart';
import '../../../core/providers/database_provider.dart';
import '../../../l10n/app_localizations.dart';

/// Shows a modal bottom sheet displaying the completion history for a task.
///
/// The sheet displays all past completions in reverse-chronological order
/// (newest first). If the task has never been completed, an empty state is shown.
Future<void> showTaskHistorySheet({
  required BuildContext context,
  required int taskId,
}) {
  return showModalBottomSheet<void>(
    context: context,
    isScrollControlled: true,
    builder: (context) => _TaskHistorySheet(taskId: taskId),
  );
}

class _TaskHistorySheet extends ConsumerWidget {
  const _TaskHistorySheet({required this.taskId});

  final int taskId;

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final theme = Theme.of(context);
    final colorScheme = theme.colorScheme;
    final l10n = AppLocalizations.of(context);

    return SafeArea(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            // Drag handle
            Container(
              width: 32,
              height: 4,
              margin: const EdgeInsets.only(bottom: 16),
              decoration: BoxDecoration(
                color: colorScheme.onSurfaceVariant.withValues(alpha: 0.4),
                borderRadius: BorderRadius.circular(2),
              ),
            ),
            // Title
            Text(
              l10n.taskHistoryTitle,
              style: theme.textTheme.titleMedium,
            ),
            const SizedBox(height: 16),
            // Completion list via StreamBuilder
            StreamBuilder<List<TaskCompletion>>(
              stream: ref
                  .read(appDatabaseProvider)
                  .tasksDao
                  .watchCompletionsForTask(taskId),
              builder: (context, snapshot) {
                if (!snapshot.hasData) {
                  return const Center(child: CircularProgressIndicator());
                }

                final completions = snapshot.data!;

                if (completions.isEmpty) {
                  return Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      Icon(
                        Icons.history,
                        size: 48,
                        color: colorScheme.onSurfaceVariant,
                      ),
                      const SizedBox(height: 8),
                      Text(
                        l10n.taskHistoryEmpty,
                        style: theme.textTheme.bodyLarge?.copyWith(
                          color: colorScheme.onSurfaceVariant,
                        ),
                      ),
                    ],
                  );
                }

                // Show count summary
                return Column(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    Text(
                      l10n.taskHistoryCount(completions.length),
                      style: theme.textTheme.bodyMedium?.copyWith(
                        color: colorScheme.onSurfaceVariant,
                      ),
                    ),
                    const SizedBox(height: 8),
                    ConstrainedBox(
                      constraints: BoxConstraints(
                        maxHeight:
                            MediaQuery.of(context).size.height * 0.4,
                      ),
                      child: ListView.builder(
                        shrinkWrap: true,
                        itemCount: completions.length,
                        itemBuilder: (context, index) {
                          final completion = completions[index];
                          final dateStr = DateFormat('dd.MM.yyyy', 'de')
                              .format(completion.completedAt);
                          final timeStr = DateFormat('HH:mm', 'de')
                              .format(completion.completedAt);
                          return ListTile(
                            leading: Icon(
                              Icons.check_circle_outline,
                              color: colorScheme.primary,
                            ),
                            title: Text(dateStr),
                            subtitle: Text(timeStr),
                          );
                        },
                      ),
                    ),
                  ],
                );
              },
            ),
            const SizedBox(height: 8),
          ],
        ),
      ),
    );
  }
}