Parallelize global search properly

Fixes #8906

app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/globalsearch/SearchScreenModel.kt

@@ -19,6 +19,8 @@ import eu.kanade.tachiyomi.util.lang.withIOContext
 import eu.kanade.tachiyomi.util.lang.withNonCancellableContext
 import eu.kanade.tachiyomi.util.system.logcat
 import kotlinx.coroutines.asCoroutineDispatcher
+import kotlinx.coroutines.async
+import kotlinx.coroutines.awaitAll
 import kotlinx.coroutines.flow.collectLatest
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
@@ -133,32 +135,36 @@ abstract class SearchScreenModel<T>(
         updateItems(initialItems)
 
         coroutineScope.launch {
-            sources.forEach { source ->
-                val page = try {
-                    withContext(coroutineDispatcher) {
-                        source.fetchSearchManga(1, query, source.getFilterList()).awaitSingle()
+            sources
+                .map { source ->
+                    async {
+                        try {
+                            val page = withContext(coroutineDispatcher) {
+                                logcat { "Searching ${source.name}" }
+                                source.fetchSearchManga(1, query, source.getFilterList()).awaitSingle()
+                            }
+
+                            val titles = withIOContext {
+                                page.mangas.map {
+                                    networkToLocalManga.await(it.toDomainManga(source.id))
+                                }
+                            }
+
+                            getAndUpdateItems { items ->
+                                val mutableMap = items.toMutableMap()
+                                mutableMap[source] = SearchItemResult.Success(titles)
+                                mutableMap.toSortedMap(sortComparator(mutableMap))
+                            }
+                        } catch (e: Exception) {
+                            getAndUpdateItems { items ->
+                                val mutableMap = items.toMutableMap()
+                                mutableMap[source] = SearchItemResult.Error(throwable = e)
+                                mutableMap.toSortedMap(sortComparator(mutableMap))
+                            }
+                        }
                     }
-                } catch (e: Exception) {
-                    getAndUpdateItems { items ->
-                        val mutableMap = items.toMutableMap()
-                        mutableMap[source] = SearchItemResult.Error(throwable = e)
-                        mutableMap.toSortedMap(sortComparator(mutableMap))
-                    }
-                    return@forEach
-                }
-
-                val titles = page.mangas.map {
-                    withIOContext {
-                        networkToLocalManga.await(it.toDomainManga(source.id))
-                    }
-                }
-
-                getAndUpdateItems { items ->
-                    val mutableMap = items.toMutableMap()
-                    mutableMap[source] = SearchItemResult.Success(titles)
-                    mutableMap.toSortedMap(sortComparator(mutableMap))
                 }
-            }
+                .awaitAll()
         }
     }
 }