refactor: expose member mention filtering (#4179)

Refactor persistence snapshot reads and mention filtering

Author: MohamadJaara

data/persistence/src/commonMain/kotlin/com/wire/kalium/persistence/dao/MetadataDAOImpl.kt

@@ -50,7 +50,9 @@ class MetadataDAOImpl internal constructor(
         }
     }
 
-    override fun valueByKeyFlow(key: String): Flow<String?> =
+    override fun valueByKeyFlow(
+        key: String
+    ): Flow<String?> =
         metadataQueries.selectValueByKey(key)
             .asFlow()
             .mapToOneOrNull()

logic/src/commonMain/kotlin/com/wire/kalium/logic/feature/conversation/MembersToMentionUseCase.kt

@@ -55,42 +55,51 @@ public class MembersToMentionUseCase internal constructor(
     public suspend operator fun invoke(conversationId: ConversationId, searchQuery: String): List<MemberDetails> =
         withContext(dispatcher.io) {
             val conversationMembers = observeConversationMembers(conversationId).first()
+            filterConversationMembers(conversationMembers, searchQuery)
+        }
 
-            // TODO apply normalization techniques that are used for other searches to the name (e.g. ö -> oe)
-
-            val usersToSearch = conversationMembers.filter {
-                it.user.id != selfUserId
-            }
-            if (searchQuery.isEmpty())
-                return@withContext usersToSearch
+    /**
+     * Search the provided conversation member snapshot without collecting the members flow.
+     */
+    public fun filterConversationMembers(
+        conversationMembers: List<MemberDetails>,
+        searchQuery: String
+    ): List<MemberDetails> {
+        // TODO apply normalization techniques that are used for other searches to the name (e.g. ö -> oe)
 
-            if (searchQuery.first().isWhitespace())
-                return@withContext listOf()
+        val usersToSearch = conversationMembers.filter {
+            it.user.id != selfUserId
+        }
+        if (searchQuery.isEmpty())
+            return usersToSearch
 
-            val rules: List<(MemberDetails) -> Boolean> = listOf(
-                { it.user.name?.startsWith(searchQuery, true) == true },
-                {
-                    it.user.name?.let { name ->
-                        nameTokens(name).firstOrNull { nameToken -> nameToken.startsWith(searchQuery, true) }
-                    } != null
-                },
-                { it.user.handle?.startsWith(searchQuery, true) == true },
-                { it.user.name?.contains(searchQuery, true) == true },
-                { it.user.handle?.contains(searchQuery, true) == true }
-            )
+        if (searchQuery.first().isWhitespace())
+            return listOf()
 
-            var foundUsers: Set<MemberDetails> = emptySet()
-            val usersToMention = mutableListOf<MemberDetails>()
-            rules.forEach { rule ->
-                val matches = usersToSearch.filter { rule(it) }
-                    .filter { !foundUsers.contains(it) }
-                    .sortedBy { it.user.name }
-                foundUsers = foundUsers.union(matches)
-                usersToMention += matches
-            }
+        val rules: List<(MemberDetails) -> Boolean> = listOf(
+            { it.user.name?.startsWith(searchQuery, true) == true },
+            {
+                it.user.name?.let { name ->
+                    nameTokens(name).firstOrNull { nameToken -> nameToken.startsWith(searchQuery, true) }
+                } != null
+            },
+            { it.user.handle?.startsWith(searchQuery, true) == true },
+            { it.user.name?.contains(searchQuery, true) == true },
+            { it.user.handle?.contains(searchQuery, true) == true }
+        )
 
-            return@withContext usersToMention
+        var foundUsers: Set<MemberDetails> = emptySet()
+        val usersToMention = mutableListOf<MemberDetails>()
+        rules.forEach { rule ->
+            val matches = usersToSearch.filter { rule(it) }
+                .filter { !foundUsers.contains(it) }
+                .sortedBy { it.user.name }
+            foundUsers = foundUsers.union(matches)
+            usersToMention += matches
         }
+
+        return usersToMention
+    }
 }
 
 /**