Fix crash with empty EnumSet

app/src/main/kotlin/org/koitharu/kotatsu/core/util/ext/Collections.kt

@@ -3,6 +3,7 @@ package org.koitharu.kotatsu.core.util.ext
 import androidx.collection.ArrayMap
 import androidx.collection.ArraySet
 import java.util.Collections
+import java.util.EnumSet
 
 @Deprecated("TODO: remove")
 fun <T> MutableList<T>.move(sourceIndex: Int, targetIndex: Int) {
@@ -61,3 +62,9 @@ fun <T> List<T>.takeMostFrequent(limit: Int): List<T> {
 		}
 	}
 }
+
+inline fun <reified E : Enum<E>> Collection<E>.toEnumSet(): EnumSet<E> = if (isEmpty()) {
+	EnumSet.noneOf(E::class.java)
+} else {
+	EnumSet.copyOf(this)
+}

app/src/main/kotlin/org/koitharu/kotatsu/search/ui/suggestion/SearchSuggestionViewModel.kt

@@ -19,12 +19,12 @@ import org.koitharu.kotatsu.core.prefs.AppSettings
 import org.koitharu.kotatsu.core.prefs.observeAsStateFlow
 import org.koitharu.kotatsu.core.ui.BaseViewModel
 import org.koitharu.kotatsu.core.ui.widgets.ChipsView
+import org.koitharu.kotatsu.core.util.ext.toEnumSet
 import org.koitharu.kotatsu.explore.data.MangaSourcesRepository
 import org.koitharu.kotatsu.parsers.model.MangaSource
 import org.koitharu.kotatsu.parsers.model.MangaTag
 import org.koitharu.kotatsu.search.domain.MangaSearchRepository
 import org.koitharu.kotatsu.search.ui.suggestion.model.SearchSuggestionItem
-import java.util.EnumSet
 import javax.inject.Inject
 
 private const val DEBOUNCE_TIMEOUT = 500L
@@ -91,7 +91,7 @@ class SearchSuggestionViewModel @Inject constructor(
 		suggestionJob?.cancel()
 		suggestionJob = combine(
 			query.debounce(DEBOUNCE_TIMEOUT),
-			sourcesRepository.observeEnabledSources().map { EnumSet.copyOf(it) },
+			sourcesRepository.observeEnabledSources().map { it.toEnumSet() },
 			::Pair,
 		).mapLatest { (searchQuery, enabledSources) ->
 			buildSearchSuggestion(searchQuery, enabledSources)

app/src/main/kotlin/org/koitharu/kotatsu/settings/sources/SourcesListViewModel.kt

@@ -18,6 +18,7 @@ import org.koitharu.kotatsu.core.util.AlphanumComparator
 import org.koitharu.kotatsu.core.util.ext.MutableEventFlow
 import org.koitharu.kotatsu.core.util.ext.call
 import org.koitharu.kotatsu.core.util.ext.map
+import org.koitharu.kotatsu.core.util.ext.toEnumSet
 import org.koitharu.kotatsu.explore.data.MangaSourcesRepository
 import org.koitharu.kotatsu.parsers.model.MangaSource
 import org.koitharu.kotatsu.parsers.util.toTitleCase
@@ -122,7 +123,7 @@ class SourcesListViewModel @Inject constructor(
 	private suspend fun buildList() = withContext(Dispatchers.Default) {
 		val allSources = repository.allMangaSources
 		val enabledSources = repository.getEnabledSources()
-		val enabledSet = EnumSet.copyOf(enabledSources)
+		val enabledSet = enabledSources.toEnumSet()
 		val query = searchQuery
 		if (!query.isNullOrEmpty()) {
 			items.value = allSources.mapNotNull {