Several small fixes (#1612)

## Description
- Fixes showing "null" in the subtitle for some tv episodes (usually
daily shows like Jeopardy)
- Partially fix holding back to return to the previous grid position
(still has focus issues)
- Show/hide tabs on the discover page similar to other pages in the app
- Prevent a warning server-side if a negative playback timestamp is sent

### Related issues
N/A

### Testing
Emulator

## Screenshots
N/A

## AI or LLM usage
None

app/src/main/java/com/github/damontecres/wholphin/ui/Extensions.kt

@@ -74,6 +74,8 @@ inline fun <T> List<T>.indexOfFirstOrNull(predicate: (T) -> Boolean): Int? {
     return if (index >= 0) index else null
 }
 
+fun Iterable<CharSequence?>.joinNotBlank(sep: String): String? = filter { it.isNotNullOrBlank() }.letNotEmpty { it.joinToString(sep) }
+
 /**
  * Try to call [FocusRequester.requestFocus], but catch & log the exception if something is not configured properly
  */

app/src/main/java/com/github/damontecres/wholphin/ui/detail/CardGrid.kt

@@ -141,7 +141,7 @@ fun <T : CardGridItem> CardGrid(
             { index: Int ->
                 if (DEBUG) Timber.v("focusOn: focusedIndex=$currentFocusedIndex, index=$index")
                 if (index != currentFocusedIndex) {
-                    previouslyFocusedIndex = focusedIndex
+                    previouslyFocusedIndex = currentFocusedIndex
                 }
                 focusedIndex = index
             }
@@ -257,10 +257,11 @@ fun <T : CardGridItem> CardGrid(
                             val newPosition = previouslyFocusedIndex
                             if (DEBUG) Timber.d("Back long pressed: newPosition=$newPosition")
                             if (newPosition > 0) {
-                                focusOn(newPosition)
                                 scope.launch(ExceptionHandler()) {
-                                    gridState.scrollToItem(newPosition, -columns)
-                                    firstFocus.tryRequestFocus()
+                                    pager.getOrNull(newPosition)
+                                    gridState.scrollToItem(newPosition)
+                                    focusOn(newPosition)
+                                    alphabetFocus = true
                                 }
                             }
                             return@onKeyEvent true

app/src/main/java/com/github/damontecres/wholphin/ui/discover/DiscoverPage.kt

@@ -42,6 +42,7 @@ fun DiscoverPage(
             0 -> {
                 SeerrDiscoverPage(
                     preferences = preferences,
+                    positionCallback = { showHeader = it.row < 1 },
                     modifier =
                         Modifier
                             .fillMaxSize()
@@ -53,6 +54,7 @@ fun DiscoverPage(
             1 -> {
                 SeerrRequestsPage(
                     focusRequesterOnEmpty = tabDetails.tabFocusRequester,
+                    positionCallback = { columns, index -> showHeader = index < columns },
                     modifier =
                         Modifier
                             .fillMaxSize()
@@ -64,6 +66,7 @@ fun DiscoverPage(
             2 -> {
                 DiscoverSearchPage(
                     preferences = preferences,
+                    positionCallback = { columns, index -> showHeader = index < columns },
                     modifier =
                         Modifier
                             .fillMaxSize()

app/src/main/java/com/github/damontecres/wholphin/ui/discover/DiscoverSearchPage.kt

@@ -102,6 +102,7 @@ class DiscoverSearchViewModel
 @Composable
 fun DiscoverSearchPage(
     preferences: UserPreferences,
+    positionCallback: (columns: Int, position: Int) -> Unit,
     modifier: Modifier = Modifier,
     viewModel: DiscoverSearchViewModel = hiltViewModel(),
 ) {
@@ -241,7 +242,10 @@ fun DiscoverSearchPage(
             onPlayItem = { _, _ -> },
             onClickPosition = { position = it.column },
             onClickDiscover = onClickDiscover,
-            positionCallback = { columns, index -> position = index },
+            positionCallback = { columns, index ->
+                position = index
+                positionCallback.invoke(columns, index)
+            },
             modifier = Modifier.fillMaxSize(),
         )
     }

app/src/main/java/com/github/damontecres/wholphin/ui/discover/SeerrDiscoverPage.kt

@@ -243,6 +243,7 @@ data class DiscoverState(
 @Composable
 fun SeerrDiscoverPage(
     preferences: UserPreferences,
+    positionCallback: (RowColumn) -> Unit,
     modifier: Modifier = Modifier,
     viewModel: SeerrDiscoverViewModel = hiltViewModel(),
 ) {
@@ -335,12 +336,16 @@ fun SeerrDiscoverPage(
                                 viewModel.navigationManager.navigateTo(item.destination)
                             },
                             onLongClickItem = { index, item -> },
-                            onCardFocus = { index -> position = RowColumn(rowIndex, index) },
+                            onCardFocus = { index ->
+                                position = RowColumn(rowIndex, index)
+                                positionCallback.invoke(position)
+                            },
                             focusRequester = focusRequesters[rowIndex],
                             enableViewMore = row.type != DiscoverRequestType.UNKNOWN,
                             onClickViewMore = {
                                 (row.items as? DataLoadingState.Success<List<DiscoverItem>>)?.data?.size?.let {
                                     position = RowColumn(rowIndex, it)
+                                    positionCallback.invoke(position)
                                 }
                                 viewModel.navigationManager.navigateTo(
                                     Destination.DiscoverMoreResult(row.type),

app/src/main/java/com/github/damontecres/wholphin/ui/discover/SeerrRequestsPage.kt

@@ -148,10 +148,12 @@ data class RequestGridItem(
 @Composable
 fun SeerrRequestsPage(
     focusRequesterOnEmpty: FocusRequester?,
+    positionCallback: (columns: Int, position: Int) -> Unit,
     modifier: Modifier = Modifier,
     viewModel: SeerrRequestsViewModel = hiltViewModel(),
 ) {
     val state by viewModel.state.collectAsState(SeerrRequestsState.EMPTY)
+    val columns = 6
 
     when (val state = state.requests) {
         is DataLoadingState.Error -> {
@@ -213,7 +215,8 @@ fun SeerrRequestsPage(
                                 modifier = mod,
                             )
                         },
-                        columns = 6,
+                        columns = columns,
+                        positionCallback = positionCallback,
                         modifier = Modifier.fillMaxSize(),
                     )
                 }

app/src/main/java/com/github/damontecres/wholphin/ui/playback/PlayExternalPage.kt

@@ -338,12 +338,15 @@ class PlayExternalViewModel
                             }
                         }
                         Timber.v("Result position: %s", position?.milliseconds)
+                        if (position != null && position < 0L) {
+                            Timber.w("Unknown stop position for external playback")
+                        }
                         if (position != null || result.data?.action != null) {
                             api.playStateApi.reportPlaybackStopped(
                                 PlaybackStopInfo(
                                     itemId = itemId,
                                     mediaSourceId = mediaSourceId,
-                                    positionTicks = position?.milliseconds?.inWholeTicks,
+                                    positionTicks = position?.milliseconds?.inWholeTicks?.takeIf { it >= 0 },
                                     failed = false,
                                 ),
                             )