Fix merged manga chapters and merged manga filtered scanlators

app/src/main/java/eu/kanade/domain/chapter/interactor/GetAvailableScanlators.kt

@@ -21,4 +21,16 @@ class GetAvailableScanlators(
         return repository.getScanlatorsByMangaIdAsFlow(mangaId)
             .map { it.cleanupAvailableScanlators() }
     }
+
+    // SY -->
+    suspend fun awaitMerge(mangaId: Long): Set<String> {
+        return repository.getScanlatorsByMergeId(mangaId)
+            .cleanupAvailableScanlators()
+    }
+
+    fun subscribeMerge(mangaId: Long): Flow<Set<String>> {
+        return repository.getScanlatorsByMergeIdAsFlow(mangaId)
+            .map { it.cleanupAvailableScanlators() }
+    }
+    // SY <--
 }

app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaScreenModel.kt

@@ -71,7 +71,10 @@ import kotlinx.coroutines.flow.catch
 import kotlinx.coroutines.flow.collectLatest
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.distinctUntilChangedBy
 import kotlinx.coroutines.flow.filter
+import kotlinx.coroutines.flow.flatMapConcat
+import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.flow.update
@@ -341,6 +344,20 @@ class MangaScreenModel(
         screenModelScope.launchIO {
             getAvailableScanlators.subscribe(mangaId)
                 .distinctUntilChanged()
+                // SY -->
+                .combine(
+                    state.map { (it as? State.Success)?.manga }
+                        .distinctUntilChangedBy { it?.source }
+                        .flatMapConcat {
+                            if (it?.source == MERGED_SOURCE_ID) {
+                                getAvailableScanlators.subscribeMerge(mangaId)
+                            } else {
+                                flowOf(emptySet())
+                            }
+                        }
+                ) { mangaScanlators, mergeScanlators ->
+                    mangaScanlators + mergeScanlators
+                } // SY <--
                 .collectLatest { availableScanlators ->
                     updateSuccessState {
                         it.copy(availableScanlators = availableScanlators.toImmutableSet())
@@ -381,7 +398,13 @@ class MangaScreenModel(
                     source = source,
                     isFromSource = isFromSource,
                     chapters = chapters,
-                    availableScanlators = getAvailableScanlators.await(mangaId).toImmutableSet(),
+                    // SY -->
+                    availableScanlators = if (manga.source == MERGED_SOURCE_ID) {
+                        getAvailableScanlators.awaitMerge(mangaId)
+                    } else {
+                        getAvailableScanlators.await(mangaId)
+                    }.toImmutableSet(),
+                    // SY <--
                     excludedScanlators = getExcludedScanlators.await(mangaId).toImmutableSet(),
                     isRefreshingData = needRefreshInfo || needRefreshChapter,
                     dialog = null,