recipe-app/flutter/lib/core/router/app_router.dart

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

import '../ui/app_shell.dart';
import '../ui/async_state_views.dart';
import '../../features/auth/data/auth_providers.dart';
import '../../core/auth/jwt_decoder.dart';
import '../../features/auth/presentation/login_screen.dart';
import '../../features/profile/presentation/profile_screen.dart';
import '../../features/recipes/presentation/create_recipe_screen.dart';
import '../../features/recipes/presentation/ai_recipe_suggestions_screen.dart';
import '../../features/recipes/presentation/recipe_detail_screen.dart';
import '../../features/recipes/presentation/recipe_edit_screen.dart';
import '../../features/recipes/presentation/recipes_screen.dart';
import '../../features/inventory/presentation/inventory_screen.dart';
import '../../features/inventory/presentation/inventory_detail_screen.dart';
import '../../features/inventory/presentation/create_inventory_screen.dart';
import '../../features/inventory/presentation/inventory_edit_screen.dart';
import '../../features/inventory/presentation/consume_inventory_screen.dart';
import '../../features/inventory/presentation/consumption_history_screen.dart';
import '../../features/meal_plan/presentation/meal_plan_screen.dart';
import '../../features/pantry/presentation/pantry_screen.dart';
import '../../features/import/presentation/import_screen.dart'
    deferred as import_ui;
import '../../features/shopping_list/presentation/shopping_list_screen.dart';
import '../../features/admin/presentation/admin_screen.dart';

int? _shellBranchIndexForPath(String path) {
  if (path.startsWith('/recipes')) return 0;
  if (path.startsWith('/inventory')) return 1;
  if (path.startsWith('/matsedel')) return 2;
  if (path.startsWith('/baslager')) return 3;
  if (path.startsWith('/import')) return 4;
  if (path.startsWith('/inkopslista')) return 5;
  if (path.startsWith('/profile')) return 6;
  if (path.startsWith('/admin')) return 7;
  return null;
}

class _DeferredRouteLoader extends StatelessWidget {
  const _DeferredRouteLoader({
    required this.loadLibrary,
    required this.builder,
  });

  final Future<void> Function() loadLibrary;
  final WidgetBuilder builder;

  @override
  Widget build(BuildContext context) {
    return FutureBuilder<void>(
      future: loadLibrary(),
      builder: (context, snapshot) {
        if (snapshot.connectionState != ConnectionState.done) {
          return const Scaffold(
            body: LoadingStateView(label: 'Laddar vy...'),
          );
        }
        if (snapshot.hasError) {
          return Scaffold(
            body: Center(
              child: Text('Kunde inte ladda sidan: ${snapshot.error}'),
            ),
          );
        }
        return builder(context);
      },
    );
  }
}

final appRouterProvider = Provider<GoRouter>((ref) {
  final authState = ref.watch(authStateProvider);

  return GoRouter(
    initialLocation: '/',
    redirect: (context, state) {
      final isLoading = authState.isLoading;
      final token = authState.maybeWhen(data: (t) => t, orElse: () => null);
      final isLoggedIn = token != null && token.isNotEmpty;
      final location = state.matchedLocation;
      final isSplash = location == '/';
      final isLogin = location == '/login';

      if (isLoading) {
        return isSplash ? null : '/';
      }

      if (isSplash) {
        return isLoggedIn ? '/recipes' : '/login';
      }

      if (!isLoggedIn && !isLogin) {
        return '/login';
      }

      if (isLoggedIn && isLogin) {
        return '/recipes';
      }

      return null;
    },
    routes: [
      GoRoute(
        path: '/',
        builder: (context, state) => const Scaffold(
          body: LoadingStateView(label: 'Startar...'),
        ),
      ),
      GoRoute(
        path: '/login',
        builder: (context, state) => const LoginScreen(),
      ),
      // Detail routes — outside ShellRoute to get full-screen with back button.
      // /recipes/create must be listed before /recipes/:id to avoid conflict.
      GoRoute(
        path: '/recipes/ai-suggestions',
        builder: (context, state) => const AiRecipeSuggestionsScreen(),
      ),
      GoRoute(
        path: '/recipes/create',
        builder: (context, state) {
          final extra = state.extra;
          String? initialMarkdown;
          String? initialImageUrl;
          // Use 'is Map' without type params — Dart reifies generics, so
          // Map<String,String?> does NOT match Map<String,dynamic> at runtime.
          if (extra is Map) {
            initialMarkdown = extra['markdown'] as String?;
            initialImageUrl = extra['imageUrl'] as String?;
          } else if (extra is String) {
            // Backwards-compat: plain string means markdown only.
            initialMarkdown = extra;
          }
          return CreateRecipeScreen(
            initialMarkdown: initialMarkdown,
            initialImageUrl: initialImageUrl,
          );
        },
      ),
      GoRoute(
        path: '/recipes/:id',
        redirect: (context, state) {
          final raw = state.pathParameters['id'] ?? '';
          if (int.tryParse(raw) == null) return '/recipes';
          return null;
        },
        builder: (context, state) {
          final id = int.parse(state.pathParameters['id']!);
          return RecipeDetailScreen(recipeId: id);
        },
      ),
      GoRoute(
        path: '/recipes/:id/edit',
        redirect: (context, state) {
          final raw = state.pathParameters['id'] ?? '';
          if (int.tryParse(raw) == null) return '/recipes';
          return null;
        },
        builder: (context, state) {
          final id = int.parse(state.pathParameters['id']!);
          return RecipeEditScreen(recipeId: id);
        },
      ),
      // Inventory detail routes — outside ShellRoute for full-screen.
      // /inventory/create must be listed before /inventory/:id.
      GoRoute(
        path: '/inventory/create',
        builder: (context, state) {
          final destination = state.uri.queryParameters['destination'];
          return CreateInventoryScreen(initialDestination: destination);
        },
      ),
      GoRoute(
        path: '/inventory/:id',
        redirect: (context, state) {
          final raw = state.pathParameters['id'] ?? '';
          if (int.tryParse(raw) == null) return '/inventory';
          return null;
        },
        builder: (context, state) {
          final id = int.parse(state.pathParameters['id']!);
          return InventoryDetailScreen(itemId: id);
        },
      ),
      GoRoute(
        path: '/inventory/:id/edit',
        redirect: (context, state) {
          final raw = state.pathParameters['id'] ?? '';
          if (int.tryParse(raw) == null) return '/inventory';
          return null;
        },
        builder: (context, state) {
          final id = int.parse(state.pathParameters['id']!);
          return InventoryEditScreen(itemId: id);
        },
      ),
      GoRoute(
        path: '/inventory/:id/consume',
        redirect: (context, state) {
          final raw = state.pathParameters['id'] ?? '';
          if (int.tryParse(raw) == null) return '/inventory';
          return null;
        },
        builder: (context, state) {
          final id = int.parse(state.pathParameters['id']!);
          return ConsumeInventoryScreen(itemId: id);
        },
      ),
      GoRoute(
        path: '/inventory/:id/history',
        redirect: (context, state) {
          final raw = state.pathParameters['id'] ?? '';
          if (int.tryParse(raw) == null) return '/inventory';
          return null;
        },
        builder: (context, state) {
          final id = int.parse(state.pathParameters['id']!);
          return ConsumptionHistoryScreen(itemId: id);
        },
      ),
      // Shell routes — shared AppShell with navigation bar.
      StatefulShellRoute.indexedStack(
        builder: (context, state, navigationShell) {
          return AppShell(
            location: state.uri.path,
            onNavigateToPath: (path) {
              final index = _shellBranchIndexForPath(path);
              if (index == null) {
                context.go(path);
                return;
              }

              if (index == navigationShell.currentIndex) {
                if (state.uri.path != path) {
                  context.go(path);
                }
                return;
              }

              navigationShell.goBranch(index);
            },
            child: navigationShell,
          );
        },
        branches: [
          StatefulShellBranch(
            routes: [
              GoRoute(
                path: '/recipes',
                builder: (context, state) => const RecipesScreen(),
              ),
            ],
          ),
          StatefulShellBranch(
            routes: [
              GoRoute(
                path: '/inventory',
                builder: (context, state) => const InventoryScreen(),
              ),
            ],
          ),
          StatefulShellBranch(
            routes: [
              GoRoute(
                path: '/matsedel',
                builder: (context, state) => const MealPlanScreen(),
              ),
            ],
          ),
          StatefulShellBranch(
            routes: [
              GoRoute(
                path: '/baslager',
                builder: (context, state) => const PantryScreen(),
              ),
            ],
          ),
          StatefulShellBranch(
            routes: [
              GoRoute(
                path: '/import',
                builder: (context, state) => _DeferredRouteLoader(
                  loadLibrary: import_ui.loadLibrary,
                  builder: (_) => import_ui.ImportScreen(),
                ),
              ),
            ],
          ),
          StatefulShellBranch(
            routes: [
              GoRoute(
                path: '/inkopslista',
                builder: (context, state) => const ShoppingListScreen(),
              ),
            ],
          ),
          StatefulShellBranch(
            routes: [
              GoRoute(
                path: '/profile',
                builder: (context, state) => const ProfileScreen(),
              ),
            ],
          ),
          StatefulShellBranch(
            routes: [
              GoRoute(
                path: '/admin',
                redirect: (context, state) {
                  final token = ref
                      .read(authStateProvider)
                      .maybeWhen(data: (t) => t, orElse: () => null);
                  return jwtIsAdmin(token) ? null : '/recipes';
                },
                builder: (context, state) {
                  final tab = AdminViewTabX.fromQuery(
                    state.uri.queryParameters['tab'],
                  );
                  return AdminScreen(initialTab: tab);
                },
              ),
            ],
          ),
        ],
      ),
    ],
  );
});