import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:tasq/models/programmer_day_sheet.model.dart';
import 'package:tasq/providers/profile_provider.dart';
import 'package:tasq/providers/programmer_day_sheets_provider.dart';
import 'package:tasq/screens/programmer_tasks/day_sheets/approvals_tab.dart';
import 'package:tasq/screens/programmer_tasks/day_sheets/day_sheet_snapshot_builder.dart';
import 'package:tasq/theme/app_theme.dart';
import 'package:tasq/utils/app_time.dart';

// ---------------------------------------------------------------------------
// Helpers
// ---------------------------------------------------------------------------

ProgrammerDaySheet _sheet({
  required String id,
  required String status,
  DateTime? workDate,
  bool autoSubmitted = false,
  int resubmissions = 0,
}) {
  final now = AppTime.now();
  final date = workDate ?? DateTime.utc(now.year, now.month, 15);
  return ProgrammerDaySheet(
    id: id,
    programmerId: 'prog-1',
    status: status,
    workDate: date,
    autoSubmitted: autoSubmitted,
    resubmissions: resubmissions,
    createdAt: now,
    updatedAt: now,
  );
}

Widget _buildApp(Widget child, {List<Override> overrides = const []}) {
  return ProviderScope(
    overrides: overrides,
    child: MaterialApp(
      theme: AppTheme.light(),
      home: Scaffold(body: child),
    ),
  );
}

// ---------------------------------------------------------------------------
// Tests
// ---------------------------------------------------------------------------

void main() {
  setUpAll(AppTime.initialize);

  // ── groupSheetsByDate ────────────────────────────────────────────────────

  group('groupSheetsByDate', () {
    test('groups by workDate, keys descending', () {
      final d1 = DateTime.utc(2024, 1, 3);
      final d2 = DateTime.utc(2024, 1, 2);
      final d3 = DateTime.utc(2024, 1, 1);

      final sheets = [
        _sheet(id: 'a', status: DaySheetStatus.pending, workDate: d2),
        _sheet(id: 'b', status: DaySheetStatus.approved, workDate: d1),
        _sheet(id: 'c', status: DaySheetStatus.draft, workDate: d3),
        _sheet(id: 'd', status: DaySheetStatus.pending, workDate: d2),
      ];

      final grouped = groupSheetsByDate(sheets);
      final keys = grouped.keys.toList();

      expect(keys, [d1, d2, d3]);
      expect(grouped[d1]!.map((s) => s.id).toList(), ['b']);
      expect(grouped[d2]!.map((s) => s.id).toList(), ['a', 'd']);
      expect(grouped[d3]!.map((s) => s.id).toList(), ['c']);
    });

    test('single sheet returns single-entry map', () {
      final d = DateTime.utc(2024, 6, 1);
      final result = groupSheetsByDate([_sheet(id: 'x', status: DaySheetStatus.pending, workDate: d)]);
      expect(result.keys.toList(), [d]);
      expect(result[d]!.length, 1);
    });

    test('empty list returns empty map', () {
      expect(groupSheetsByDate([]), isEmpty);
    });
  });

  // ── approvalCounts ───────────────────────────────────────────────────────

  group('approvalCounts', () {
    test('counts pending, awaiting (disapproved) and approved', () {
      final sheets = [
        _sheet(id: '1', status: DaySheetStatus.pending),
        _sheet(id: '2', status: DaySheetStatus.pending),
        _sheet(id: '3', status: DaySheetStatus.disapproved),
        _sheet(id: '4', status: DaySheetStatus.approved),
        _sheet(id: '5', status: DaySheetStatus.draft),
      ];

      final counts = approvalCounts(sheets);
      expect(counts.pending, 2);
      expect(counts.awaiting, 1);
      expect(counts.approved, 1);
    });

    test('all zero for empty list', () {
      final counts = approvalCounts([]);
      expect(counts.pending, 0);
      expect(counts.awaiting, 0);
      expect(counts.approved, 0);
    });

    test('draft sheets are not counted', () {
      final counts = approvalCounts([
        _sheet(id: '1', status: DaySheetStatus.draft),
        _sheet(id: '2', status: DaySheetStatus.draft),
      ]);
      expect(counts.pending, 0);
      expect(counts.awaiting, 0);
      expect(counts.approved, 0);
    });
  });

  // ── ApprovalsTab widget ──────────────────────────────────────────────────

  group('ApprovalsTab', () {
    List<ProgrammerDaySheet> _pendingSheets(int n) {
      final now = AppTime.now();
      return List.generate(
        n,
        (i) => _sheet(
          id: 'sheet-$i',
          status: DaySheetStatus.pending,
          workDate: DateTime.utc(now.year, now.month, 15),
        ),
      );
    }

    testWidgets(
        'selecting 2 of 3 pending cards shows Approve selected (2)',
        (tester) async {
      final sheets = _pendingSheets(3);

      await tester.pumpWidget(
        _buildApp(
          const ApprovalsTab(),
          overrides: [
            allDaySheetsProvider.overrideWith(
              (ref) => Stream.value(sheets),
            ),
            profilesProvider.overrideWith(
              (ref) => Stream.value([]),
            ),
            isStrictAdminProvider.overrideWith((ref) => true),
            currentUserIdProvider.overrideWith((ref) => 'admin-1'),
          ],
        ),
      );

      // Let the stream settle.
      await tester.pump();
      await tester.pump();

      // All 3 pending cards should be visible with checkboxes.
      final checkboxes = find.byType(Checkbox);
      expect(checkboxes, findsAtLeastNWidgets(2));

      // Select two cards.
      await tester.tap(checkboxes.at(0));
      await tester.pump();
      await tester.tap(checkboxes.at(1));
      await tester.pump();

      // The approve button must reflect the selection count.
      expect(find.text('Approve selected (2)'), findsOneWidget);
    });
  });
}