Refactor followSetNotesFlow() and introduce FollowSetFeedFilter.

amethyst/src/main/java/com/vitorpamplona/amethyst/model/Account.kt

@@ -121,7 +121,6 @@ import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.combineTransform
 import kotlinx.coroutines.flow.emitAll
 import kotlinx.coroutines.flow.flatMapLatest
-import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.flow.flowOn
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.mapLatest
@@ -2899,11 +2898,6 @@ class Account(
 
     fun getFollowSetNotes(): List<AddressableNote> = LocalCache.getFollowSetsFor(userProfile())
 
-    suspend fun followSetNotesFlow() =
-        flowOf(getFollowSetNotes())
-            .flowOn(Dispatchers.IO)
-            .stateIn(scope)
-
     fun loadUserFollowSets() {
         val sets =
             getFollowSetNotes()
@@ -2913,6 +2907,8 @@ class Account(
         userProfile().followSets = sets
     }
 
+    fun followSetNotesFlow() = userProfile().flow().followSets.stateFlow
+
     fun getMuteListFlow(): StateFlow<NoteState> = getMuteListNote().flow().metadata.stateFlow
 
     fun getBlockList(): PeopleListEvent? = getBlockListNote().event as? PeopleListEvent

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/dal/FollowSetFeedFilter.kt

@@ -0,0 +1,64 @@
+/**
+ * Copyright (c) 2024 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.ui.dal
+
+import com.vitorpamplona.amethyst.model.Account
+import com.vitorpamplona.quartz.events.PeopleListEvent
+
+class FollowSetFeedFilter(
+    val account: Account,
+) : FeedFilter<PeopleListEvent.FollowSet>() {
+    override fun feedKey(): String = account.userProfile().pubkeyHex
+
+    private fun mapEventToSet(event: PeopleListEvent): PeopleListEvent.FollowSet {
+        val dTag = event.dTag()
+        val listTitle = event.title() ?: dTag
+        val listDescription = event.description() ?: ""
+        val publicFollows = event.filterTagList("p", null)
+        val privateFollows = mutableListOf<String>()
+        event.privateTaggedUsers(account.signer) { userList -> privateFollows.addAll(userList) }
+        return if (publicFollows.isEmpty() && privateFollows.isNotEmpty()) {
+            PeopleListEvent.FollowSet(
+                isPrivate = true,
+                title = listTitle,
+                description = listDescription,
+                profileList = privateFollows.toSet(),
+            )
+        } else if (publicFollows.isNotEmpty() && privateFollows.isEmpty()) {
+            PeopleListEvent.FollowSet(
+                isPrivate = false,
+                title = listTitle,
+                description = listDescription,
+                profileList = publicFollows.toSet(),
+            )
+        } else {
+            throw Exception("Mixed follow sets are not yet supported.")
+        }
+    }
+
+    override fun feed(): List<PeopleListEvent.FollowSet> =
+        account
+            .followSetNotesFlow()
+            .value
+            .user
+            .followSets
+            .map { setEntry -> mapEventToSet(setEntry.value) }
+}