tmpd6rohdx0.kotlin

sealed class TabRoute {
    data object Home : TabRoute()
    data object Explore : TabRoute()
    data object Messages : TabRoute()
    data object Profile : TabRoute()
}

sealed class HomeStackRoute {
    data object Feed : HomeStackRoute()
    data class PostDetail(val postId: String) : HomeStackRoute()
    data class UserProfile(val userId: String) : HomeStackRoute()
}

sealed class ExploreStackRoute {
    data object Trending : ExploreStackRoute()
    data class SearchResults(val query: String) : ExploreStackRoute()
}

@Composable
fun MainTabNavigation() {
    var selectedTab by remember { mutableStateOf<TabRoute>(TabRoute.Home) }
    
    val tabNavControllers = remember {
        mapOf(
            TabRoute.Home to NavController(HomeStackRoute.Feed),
            TabRoute.Explore to NavController(ExploreStackRoute.Trending),
            TabRoute.Messages to NavController(Route.Messages),
            TabRoute.Profile to NavController(Route.Profile)
        )
    }
    
    Scaffold(
        bottomBar = {
            NavigationBar {
                listOf(
                    TabRoute.Home,
                    TabRoute.Explore,
                    TabRoute.Messages,
                    TabRoute.Profile
                ).forEach { tab ->
                    NavigationBarItem(
                        icon = { Icon(tab.getIcon(), contentDescription = null) },
                        label = { Text(tab.getTitle()) },
                        selected = selectedTab == tab,
                        onClick = {
                            if (selectedTab != tab) {
                                selectedTab = tab
                            }
                        }
                    )
                }
            }
        }
    ) { innerPadding ->
        Box(modifier = Modifier.padding(innerPadding)) {
            when (selectedTab) {
                TabRoute.Home -> HomeTabNavHost(tabNavControllers[TabRoute.Home]!!)
                TabRoute.Explore -> ExploreTabNavHost(tabNavControllers[TabRoute.Explore]!!)
                TabRoute.Messages -> MessagesScreen()
                TabRoute.Profile -> ProfileScreen()
            }
        }
    }
}

@Composable
private fun HomeTabNavHost(navController: NavController) {
    NavHost(navController, HomeStackRoute.Feed) {
        composable<HomeStackRoute.Feed> {
            FeedScreen(navController)
        }
        
        composable<HomeStackRoute.PostDetail> { entry ->
            val postId = (entry.toRoute() as HomeStackRoute.PostDetail).postId
            PostDetailScreen(postId, navController)
        }
        
        composable<HomeStackRoute.UserProfile> { entry ->
            val userId = (entry.toRoute() as HomeStackRoute.UserProfile).userId
            UserProfileScreen(userId, navController)
        }
    }
}

@Composable
private fun ExploreTabNavHost(navController: NavController) {
    NavHost(navController, ExploreStackRoute.Trending) {
        composable<ExploreStackRoute.Trending> {
            TrendingScreen(navController)
        }
        
        composable<ExploreStackRoute.SearchResults> { entry ->
            val query = (entry.toRoute() as ExploreStackRoute.SearchResults).query
            SearchResultsScreen(query, navController)
        }
    }
}

@Composable
fun FeedScreen(navController: NavController) {
    var posts by remember { mutableStateOf<List<Post>>(emptyList()) }
    
    LaunchedEffect(Unit) {
        // Load posts from API
    }
    
    LazyColumn {
        items(posts) { post ->
            PostCard(
                post = post,
                onPostClick = {
                    navController.navigate(HomeStackRoute.PostDetail(post.id))
                },
                onUserClick = {
                    navController.navigate(HomeStackRoute.UserProfile(post.userId))
                }
            )
        }
    }
}