import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';

import '../screens/auth_screens.dart';
import '../screens/availability_screen.dart';
import '../screens/clock_screen.dart';
import '../screens/compliance_screens.dart';
import '../screens/home_shell.dart';
import '../screens/onboarding_screens.dart';
import '../screens/pay_screens.dart';
import '../screens/profile_detail_screens.dart';
import '../screens/profile_screen.dart';
import '../screens/requirements_screen.dart';
import '../screens/settings_screens.dart';
import '../screens/shift_detail_screen.dart';
import '../screens/shifts_screen.dart';
import '../screens/timecard_screens.dart';
import '../screens/today_screen.dart';
import '../state/compliance_controller.dart';
import 'transitions.dart';

final _rootKey = GlobalKey<NavigatorState>();

ComplianceSection _sectionFromName(String name) =>
    ComplianceSection.values.firstWhere(
      (s) => s.name == name,
      orElse: () => ComplianceSection.documents,
    );

/// A screen that replaces what came before it.
GoRoute _fadeRoute(String path, Widget Function() build) => GoRoute(
  path: path,
  pageBuilder: (_, state) => Transitions.fade(state, build()),
);

/// A screen pushed on top of the shell.
GoRoute _detailRoute(
  String path,
  Widget Function(GoRouterState) build, {
  List<RouteBase> routes = const [],
}) => GoRoute(
  path: path,
  parentNavigatorKey: _rootKey,
  pageBuilder: (_, state) => Transitions.push(state, build(state)),
  routes: routes,
);

/// Sign-in lives outside the shell; the five tabs each keep their own stack,
/// and detail screens push over the whole shell.
final router = GoRouter(
  navigatorKey: _rootKey,
  initialLocation: '/',
  routes: [
    _fadeRoute('/', SplashScreen.new),
    _fadeRoute('/onboarding', OnboardingScreen.new),
    _fadeRoute('/welcome', WelcomeScreen.new),
    _fadeRoute('/verified', VerifiedScreen.new),
    _fadeRoute('/permissions', PermissionsScreen.new),

    // The two sign-in steps are pushed, so back gestures read correctly.
    _detailRoute('/phone', (_) => const PhoneScreen()),
    _detailRoute('/otp', (_) => const OtpScreen()),

    // Branch order is the tab order, and it matches the prototype: Today sits
    // in the middle, with the two browsing tabs to its left and the two
    // personal ones to its right. KrowNavBar's items must stay in step.
    StatefulShellRoute.indexedStack(
      builder: (_, _, shell) => HomeShell(navigationShell: shell),
      branches: [
        StatefulShellBranch(
          routes: [
            GoRoute(path: '/shifts', builder: (_, _) => const ShiftsScreen()),
          ],
        ),
        StatefulShellBranch(
          routes: [GoRoute(path: '/pay', builder: (_, _) => const PayScreen())],
        ),
        StatefulShellBranch(
          routes: [
            GoRoute(path: '/today', builder: (_, _) => const TodayScreen()),
          ],
        ),
        StatefulShellBranch(
          routes: [
            GoRoute(path: '/clock', builder: (_, _) => const ClockScreen()),
          ],
        ),
        StatefulShellBranch(
          routes: [
            GoRoute(path: '/profile', builder: (_, _) => const ProfileScreen()),
          ],
        ),
      ],
    ),

    _detailRoute(
      '/shift/:id',
      (state) => ShiftDetailScreen(shiftId: state.pathParameters['id']!),
      routes: [
        _detailRoute(
          'requirements',
          (state) => RequirementsScreen(shiftId: state.pathParameters['id']!),
        ),
      ],
    ),
    _detailRoute('/availability', (_) => const AvailabilityScreen()),
    _detailRoute('/timecards', (_) => const TimecardsScreen()),
    _detailRoute(
      '/timecard/:id',
      (state) => TimecardReviewScreen(timecardId: state.pathParameters['id']!),
    ),
    _detailRoute('/payroll', (_) => const PayrollScheduleScreen()),
    _detailRoute(
      '/payment/:id',
      (state) => PaymentDetailScreen(shiftId: state.pathParameters['id']!),
    ),
    _detailRoute(
      '/compliance',
      (_) => const ComplianceHubScreen(),
      routes: [
        _detailRoute(
          ':section',
          (state) => ComplianceListScreen(
            section: _sectionFromName(state.pathParameters['section']!),
          ),
          routes: [
            _detailRoute(
              ':itemId',
              (state) => ComplianceDetailScreen(
                section: _sectionFromName(state.pathParameters['section']!),
                itemId: state.pathParameters['itemId']!,
              ),
            ),
          ],
        ),
      ],
    ),
    _detailRoute('/emergency-contacts', (_) => const EmergencyContactsScreen()),
    _detailRoute('/skills', (_) => const SkillsScreen()),
    _detailRoute('/direct-deposit', (_) => const DirectDepositScreen()),
    _detailRoute('/benefits', (_) => const BenefitsScreen()),
    _detailRoute('/settings', (_) => const SettingsScreen()),
    _detailRoute('/support', (_) => const SupportScreen()),
    _detailRoute('/faqs', (_) => const FaqScreen()),
    _detailRoute('/privacy', (_) => const PrivacyScreen()),
  ],
);