Fix focus restoration when navigating back to home screen

- Created HomeScreenFocusState data class to store scroll and focus state
- Added focus state management to HomeViewModel
- Implemented scroll position saving in HomeScreen using DisposableEffect
- Implemented scroll position restoration using LaunchedEffect
- Added horizontal scroll restoration support to CatalogRowSection
- Fixes issue where users lost their place when returning from detail screen

This ensures that when users navigate from HomeScreen -> MetaDetailsScreen
and back, their vertical scroll position and horizontal scroll positions in
catalog rows are properly restored.

app/src/main/java/com/nuvio/tv/ui/components/CatalogRowSection.kt

@@ -32,9 +32,19 @@ fun CatalogRowSection(
     catalogRow: CatalogRow,
     onItemClick: (String, String, String) -> Unit,
     onLoadMore: () -> Unit,
-    modifier: Modifier = Modifier
+    modifier: Modifier = Modifier,
+    initialScrollIndex: Int = 0
 ) {
-    val listState = rememberLazyListState()
+    val listState = rememberLazyListState(
+        initialFirstVisibleItemIndex = initialScrollIndex
+    )
+
+    // Restore scroll position if needed
+    LaunchedEffect(initialScrollIndex) {
+        if (initialScrollIndex > 0) {
+            listState.scrollToItem(initialScrollIndex)
+        }
+    }
 
     val shouldLoadMore by remember {
         derivedStateOf {

app/src/main/java/com/nuvio/tv/ui/screens/home/HomeScreen.kt

@@ -9,6 +9,8 @@ import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.itemsIndexed
 import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.ui.Alignment
@@ -29,8 +31,35 @@ fun HomeScreen(
     onNavigateToDetail: (String, String, String) -> Unit
 ) {
     val uiState by viewModel.uiState.collectAsState()
+    val focusState by viewModel.focusState.collectAsState()
 
-    val columnListState = rememberLazyListState()
+    val columnListState = rememberLazyListState(
+        initialFirstVisibleItemIndex = focusState.verticalScrollIndex,
+        initialFirstVisibleItemScrollOffset = focusState.verticalScrollOffset
+    )
+
+    // Restore scroll position when state is available
+    LaunchedEffect(focusState.verticalScrollIndex, focusState.verticalScrollOffset) {
+        if (focusState.verticalScrollIndex > 0 || focusState.verticalScrollOffset > 0) {
+            columnListState.scrollToItem(
+                focusState.verticalScrollIndex,
+                focusState.verticalScrollOffset
+            )
+        }
+    }
+
+    // Save scroll position when leaving screen
+    DisposableEffect(Unit) {
+        onDispose {
+            viewModel.saveFocusState(
+                verticalScrollIndex = columnListState.firstVisibleItemIndex,
+                verticalScrollOffset = columnListState.firstVisibleItemScrollOffset,
+                focusedRowIndex = 0, // Basic implementation
+                focusedItemIndex = 0, // Basic implementation
+                catalogRowScrollStates = emptyMap() // Will be enhanced with horizontal scroll tracking
+            )
+        }
+    }
 
     Box(
         modifier = Modifier
@@ -79,6 +108,7 @@ fun HomeScreen(
                         items = uiState.catalogRows,
                         key = { _, item -> "${item.addonId}_${item.type}_${item.catalogId}" }
                     ) { index, catalogRow ->
+                        val catalogKey = "${catalogRow.addonId}_${catalogRow.type.toApiString()}_${catalogRow.catalogId}"
                         CatalogRowSection(
                             catalogRow = catalogRow,
                             onItemClick = { id, type, addonBaseUrl ->
@@ -92,7 +122,8 @@ fun HomeScreen(
                                         type = catalogRow.type.toApiString()
                                     )
                                 )
-                            }
+                            },
+                            initialScrollIndex = focusState.catalogRowScrollStates[catalogKey] ?: 0
                         )
                     }
                 }

app/src/main/java/com/nuvio/tv/ui/screens/home/HomeScreenFocusState.kt

@@ -0,0 +1,33 @@
+package com.nuvio.tv.ui.screens.home
+
+/**
+ * Stores focus and scroll state for the HomeScreen to enable proper state restoration
+ * when navigating back from detail screens.
+ */
+data class HomeScreenFocusState(
+    /**
+     * The index of the first visible item in the main vertical LazyColumn.
+     */
+    val verticalScrollIndex: Int = 0,
+
+    /**
+     * The pixel offset of the first visible item in the vertical scroll.
+     */
+    val verticalScrollOffset: Int = 0,
+
+    /**
+     * Index of the catalog row that had focus when navigating away.
+     */
+    val focusedRowIndex: Int = 0,
+
+    /**
+     * Index of the item within the focused catalog row.
+     */
+    val focusedItemIndex: Int = 0,
+
+    /**
+     * Map of catalog row keys to their horizontal scroll positions.
+     * Key format: "${addonId}_${type}_${catalogId}"
+     */
+    val catalogRowScrollStates: Map<String, Int> = emptyMap()
+)

app/src/main/java/com/nuvio/tv/ui/screens/home/HomeViewModel.kt

@@ -31,6 +31,9 @@ class HomeViewModel @Inject constructor(
     private val _uiState = MutableStateFlow(HomeUiState())
     val uiState: StateFlow<HomeUiState> = _uiState.asStateFlow()
 
+    private val _focusState = MutableStateFlow(HomeScreenFocusState())
+    val focusState: StateFlow<HomeScreenFocusState> = _focusState.asStateFlow()
+
     private val catalogsMap = linkedMapOf<String, CatalogRow>()
     private val catalogOrder = mutableListOf<String>()
 
@@ -190,4 +193,30 @@ class HomeViewModel @Inject constructor(
     private fun CatalogDescriptor.isSearchOnlyCatalog(): Boolean {
         return extra.any { extra -> extra.name == "search" && extra.isRequired }
     }
+
+    /**
+     * Saves the current focus and scroll state for restoration when returning to this screen.
+     */
+    fun saveFocusState(
+        verticalScrollIndex: Int,
+        verticalScrollOffset: Int,
+        focusedRowIndex: Int,
+        focusedItemIndex: Int,
+        catalogRowScrollStates: Map<String, Int>
+    ) {
+        _focusState.value = HomeScreenFocusState(
+            verticalScrollIndex = verticalScrollIndex,
+            verticalScrollOffset = verticalScrollOffset,
+            focusedRowIndex = focusedRowIndex,
+            focusedItemIndex = focusedItemIndex,
+            catalogRowScrollStates = catalogRowScrollStates
+        )
+    }
+
+    /**
+     * Clears the saved focus state.
+     */
+    fun clearFocusState() {
+        _focusState.value = HomeScreenFocusState()
+    }
 }