Merge pull request #4304 from vitorpamplona/claude/nice-clarke-q9p5kp

Add NIP-17 group chat subject rename system message

amethyst/src/main/java/com/vitorpamplona/amethyst/service/notifications/renderers/DirectMessageNotification.kt

@@ -24,7 +24,11 @@ import android.content.Context
 import com.vitorpamplona.amethyst.commons.model.Account
 import com.vitorpamplona.amethyst.commons.model.User
 import com.vitorpamplona.amethyst.commons.model.cache.LocalCache
+import com.vitorpamplona.amethyst.commons.model.privateChats.isSubjectOnlyChatMessage
 import com.vitorpamplona.amethyst.commons.notifications.NotificationContent
+import com.vitorpamplona.amethyst.commons.resources.Res
+import com.vitorpamplona.amethyst.commons.resources.chat_notification_renamed_conversation_to
+import com.vitorpamplona.amethyst.commons.ui.loadStringRes
 import com.vitorpamplona.amethyst.service.notifications.NotificationCategory
 import com.vitorpamplona.amethyst.service.notifications.NotificationEnricher
 import com.vitorpamplona.amethyst.service.notifications.NotificationRoutes
@@ -33,6 +37,7 @@ import com.vitorpamplona.amethyst.service.notifications.NotificationUtils.ReplyA
 import com.vitorpamplona.amethyst.service.notifications.NotificationUtils.postConversation
 import com.vitorpamplona.amethyst.service.notifications.notificationManager
 import com.vitorpamplona.quartz.nip04Dm.messages.EncryptedDmEvent
+import com.vitorpamplona.quartz.nip14Subject.subject
 import com.vitorpamplona.quartz.nip17Dm.base.ChatroomKey
 import com.vitorpamplona.quartz.nip17Dm.files.ChatMessageEncryptedFileHeaderEvent
 import com.vitorpamplona.quartz.nip17Dm.messages.ChatMessageEvent
@@ -94,7 +99,13 @@ object DirectMessageNotification {
             if (decrypt) {
                 NotificationContent.decryptContent(chatNote, account.signer) ?: return
             } else {
-                chatNote.event?.content ?: return
+                val event = chatNote.event ?: return
+                // A rename with no text would post an empty notification; say what it did instead.
+                if (event.isSubjectOnlyChatMessage()) {
+                    loadStringRes(Res.string.chat_notification_renamed_conversation_to, event.subject() ?: "")
+                } else {
+                    event.content
+                }
             }
 
         val accountNpub = NotificationRoutes.accountNpub(account)

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/model/privateChats/ChatPreview.kt

@@ -23,6 +23,8 @@ package com.vitorpamplona.amethyst.commons.model.privateChats
 import com.vitorpamplona.quartz.nip01Core.core.Event
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip04Dm.messages.EncryptedDmEvent
+import com.vitorpamplona.quartz.nip14Subject.subject
+import com.vitorpamplona.quartz.nip17Dm.messages.ChatMessageEvent
 import com.vitorpamplona.quartz.nip37Drafts.DraftWrapEvent
 import com.vitorpamplona.quartz.nip51Lists.PrivateReplaceableTagArrayEvent
 import com.vitorpamplona.quartz.nip51Lists.PrivateTagArrayEvent
@@ -58,6 +60,16 @@ fun Event.hasEncryptedContent(): Boolean =
         else -> false
     }
 
+/**
+ * A NIP-17 message that only renames the conversation: it carries a `subject` tag and no text.
+ * It has nothing to show as a message body, so the feed, the room list and the notification each
+ * narrate it as a rename instead. A rename sent with an explanation is a regular message.
+ *
+ * Checks the content first: almost every message has text, and `isBlank` stops at its first
+ * non-space character, so the tag scan only runs for the rare empty one.
+ */
+fun Event.isSubjectOnlyChatMessage(): Boolean = this is ChatMessageEvent && content.isBlank() && subject() != null
+
 /**
  * What a chat row should render for a message, once the raw ciphertext is off the table.
  *
@@ -70,6 +82,11 @@ sealed interface ChatPreview {
         val text: String,
     ) : ChatPreview
 
+    /** A message that only renamed the conversation ([isSubjectOnlyChatMessage]) to [subject]. */
+    data class SubjectChange(
+        val subject: String,
+    ) : ChatPreview
+
     /** Encrypted, decryptable by this account, plaintext not available yet. */
     data object Decrypting : ChatPreview
 
@@ -97,6 +114,8 @@ fun chatPreviewOf(
 ): ChatPreview {
     if (event == null) return ChatPreview.Missing
 
+    if (event.isSubjectOnlyChatMessage()) return ChatPreview.SubjectChange(event.subject() ?: "")
+
     if (!event.hasEncryptedContent()) return ChatPreview.Body(decrypted ?: event.content)
 
     // Never trust `event.content` from here down: it is ciphertext.

commons/src/commonTest/kotlin/com/vitorpamplona/amethyst/commons/model/privateChats/ChatPreviewTest.kt

@@ -59,6 +59,50 @@ class ChatPreviewTest {
             sig = someSig,
         )
 
+    private fun nip17Rename(content: String = "") =
+        ChatMessageEvent(
+            id = "rn".padEnd(64, '0'),
+            pubKey = other,
+            createdAt = 1_000,
+            tags = arrayOf(arrayOf("p", me), arrayOf("subject", "Weekend plans")),
+            content = content,
+            sig = someSig,
+        )
+
+    // ---- subject-only renames ------------------------------------------------
+
+    @Test
+    fun renameWithoutTextIsSubjectOnly() {
+        assertTrue(nip17Rename().isSubjectOnlyChatMessage())
+        assertTrue(nip17Rename(content = "  \n").isSubjectOnlyChatMessage())
+    }
+
+    @Test
+    fun renameWithTextIsARegularMessage() {
+        assertFalse(nip17Rename(content = "new goals").isSubjectOnlyChatMessage())
+    }
+
+    @Test
+    fun messageWithoutSubjectIsNotARename() {
+        assertFalse(nip17Rumor().isSubjectOnlyChatMessage())
+    }
+
+    @Test
+    fun renamePreviewNamesTheNewSubject() {
+        assertEquals(
+            ChatPreview.SubjectChange("Weekend plans"),
+            chatPreviewOf(nip17Rename(), decrypted = null, myPubKey = me, canDecrypt = true),
+        )
+    }
+
+    @Test
+    fun renameWithTextPreviewsTheText() {
+        assertEquals(
+            ChatPreview.Body("new goals"),
+            chatPreviewOf(nip17Rename(content = "new goals"), decrypted = null, myPubKey = me, canDecrypt = true),
+        )
+    }
+
     // ---- hasEncryptedContent -------------------------------------------------
 
     @Test

commonsUI/src/commonMain/composeResources/values/strings.xml

@@ -2323,6 +2323,11 @@
     <string name="chat_system_created_channel">%1$s created the channel %2$s</string>
     <string name="chat_system_created_channel_unnamed">%1$s created the channel</string>
     <string name="chat_system_updated_channel">%1$s updated the channel profile</string>
+    <string name="chat_system_renamed_conversation">%1$s renamed the conversation</string>
+    <string name="chat_system_renamed_conversation_you">You renamed the conversation</string>
+    <string name="chat_system_renamed_conversation_to">%1$s renamed the conversation to %2$s</string>
+    <string name="chat_system_renamed_conversation_to_you">You renamed the conversation to %1$s</string>
+    <string name="chat_notification_renamed_conversation_to">Renamed the conversation to %1$s</string>
     <string name="buzz_message_edited">(edited)</string>
     <string name="buzz_diff_truncated">(diff truncated)</string>
     <string name="buzz_system_member_joined">%1$s joined</string>

commonsUI/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chats/ui/ChatGroupPosition.kt

@@ -26,6 +26,7 @@ import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.vitorpamplona.amethyst.commons.model.Note
+import com.vitorpamplona.amethyst.commons.model.privateChats.isSubjectOnlyChatMessage
 import com.vitorpamplona.amethyst.commons.ui.note.dateFormatter
 import com.vitorpamplona.amethyst.commons.ui.theme.ChatBubbleShapeMe
 import com.vitorpamplona.amethyst.commons.ui.theme.ChatBubbleShapeMeBottom
@@ -92,7 +93,8 @@ const val CHAT_GROUP_WINDOW_SECONDS = 10 * 60L
 
 /**
  * Event kinds that don't render as regular bubbles (zaps, raids, clips) or that
- * read as system messages (channel admin events) never join an author run.
+ * read as system messages (channel admin events, NIP-17 renames) never join an
+ * author run.
  */
 private fun isGroupableEvent(event: Event?): Boolean =
     event != null &&
@@ -100,7 +102,8 @@ private fun isGroupableEvent(event: Event?): Boolean =
         event !is LiveActivitiesRaidEvent &&
         event !is LiveActivitiesClipEvent &&
         event !is ChannelCreateEvent &&
-        event !is ChannelMetadataEvent
+        event !is ChannelMetadataEvent &&
+        !event.isSubjectOnlyChatMessage()
 
 /**
  * Whether [newer] continues the author run started by [older]. Mirrors the break

commonsUI/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chats/ui/ChatSystemMessage.kt

@@ -54,12 +54,17 @@ import com.vitorpamplona.amethyst.commons.ui.theme.grayText
  * [leading] is an optional slot rendered inside the pill, before the text — used to
  * put the avatar of whoever the line is about ("Alice joined") next to the sentence,
  * so a membership change is recognizable without reading the name.
+ *
+ * [trailing] is an optional slot rendered inside the pill, after the text — used by
+ * system lines that are real messages (a NIP-17 rename) to keep their time and
+ * delivery ticks without wrapping them in an otherwise empty bubble.
  */
 @Composable
 fun ChatSystemMessage(
     text: String,
     onClick: (() -> Unit)? = null,
     leading: (@Composable () -> Unit)? = null,
+    trailing: (@Composable () -> Unit)? = null,
 ) {
     Row(
         modifier =
@@ -78,16 +83,27 @@ fun ChatSystemMessage(
                     Modifier
                 },
         ) {
-            if (leading == null) {
+            if (leading == null && trailing == null) {
                 SystemMessageText(text)
             } else {
                 Row(
                     verticalAlignment = Alignment.CenterVertically,
                     horizontalArrangement = Arrangement.spacedBy(6.dp),
-                    modifier = Modifier.padding(start = 8.dp),
+                    modifier =
+                        Modifier.padding(
+                            start = if (leading != null) 8.dp else 0.dp,
+                            end = if (trailing != null) 10.dp else 0.dp,
+                        ),
                 ) {
-                    leading()
-                    SystemMessageText(text, startPadding = 0.dp)
+                    leading?.invoke()
+                    SystemMessageText(
+                        text = text,
+                        startPadding = if (leading != null) 0.dp else 12.dp,
+                        endPadding = if (trailing != null) 0.dp else 12.dp,
+                        // Lets a long sentence wrap instead of pushing the trailing slot out of the pill.
+                        modifier = Modifier.weight(1f, fill = false),
+                    )
+                    trailing?.invoke()
                 }
             }
         }
@@ -98,13 +114,15 @@ fun ChatSystemMessage(
 private fun SystemMessageText(
     text: String,
     startPadding: Dp = 12.dp,
+    endPadding: Dp = 12.dp,
+    modifier: Modifier = Modifier,
 ) {
     Text(
         text = text,
         fontSize = Font12SP,
         color = MaterialTheme.colorScheme.grayText,
         textAlign = TextAlign.Center,
-        modifier = Modifier.padding(start = startPadding, end = 12.dp, top = 5.dp, bottom = 5.dp),
+        modifier = modifier.padding(start = startPadding, end = endPadding, top = 5.dp, bottom = 5.dp),
     )
 }
 
@@ -118,5 +136,10 @@ private fun ChatSystemMessagePreview() {
             "Bob was added by Alice",
             leading = { Box(Modifier.size(Size18dp).clip(CircleShape).background(MaterialTheme.colorScheme.primary)) },
         )
+        ChatSystemMessage(
+            "You renamed the conversation",
+            leading = { Box(Modifier.size(Size18dp).clip(CircleShape).background(MaterialTheme.colorScheme.primary)) },
+            trailing = { Text("10:42", fontSize = Font12SP, color = MaterialTheme.colorScheme.grayText) },
+        )
     }
 }

commonsUI/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/ui/screen/loggedIn/chats/feed/ChatFeedView.kt

@@ -43,6 +43,7 @@ import com.vitorpamplona.amethyst.commons.feeds.FeedContentState
 import com.vitorpamplona.amethyst.commons.feeds.FeedState
 import com.vitorpamplona.amethyst.commons.model.Note
 import com.vitorpamplona.amethyst.commons.model.composer.DraftTagState
+import com.vitorpamplona.amethyst.commons.model.privateChats.isSubjectOnlyChatMessage
 import com.vitorpamplona.amethyst.commons.ui.components.CrossfadeIfEnabled
 import com.vitorpamplona.amethyst.commons.ui.feeds.FeedEmpty
 import com.vitorpamplona.amethyst.commons.ui.feeds.FeedError
@@ -55,6 +56,19 @@ import com.vitorpamplona.amethyst.commons.viewmodels.AccountViewModel
 import com.vitorpamplona.quartz.nip37Drafts.DraftWrapEvent
 import kotlinx.coroutines.launch
 
+private const val SUBJECT_ONLY_CONTENT_TYPE = -2
+
+/**
+ * The lazy-list content type of a chat row: its event kind, except that a NIP-17 rename with no
+ * text gets its own type. It renders as a system pill rather than a bubble, so letting it share
+ * kind 14's slot with ordinary messages would make the list rebuild one layout into the other
+ * whenever a recycled slot crossed between the two.
+ */
+private fun chatRowContentType(item: Note): Int {
+    val event = item.event ?: return -1
+    return if (event.isSubjectOnlyChatMessage()) SUBJECT_ONLY_CONTENT_TYPE else event.kind
+}
+
 /**
  * A caller's own rendering for feed rows that are not chat bubbles.
  *
@@ -245,7 +259,7 @@ fun ChatFeedLoaded(
         reverseLayout = true,
         state = listState,
     ) {
-        itemsIndexed(items.list, key = { _, item -> item.idHex }, contentType = { _, item -> item.event?.kind ?: -1 }) { index, item ->
+        itemsIndexed(items.list, key = { _, item -> item.idHex }, contentType = { _, item -> chatRowContentType(item) }) { index, item ->
             val noteEvent = item.event
             if (avoidDraft == null || noteEvent !is DraftWrapEvent || noteEvent.dTag() !in avoidDraft.usedDraftTags) {
                 // Reverse layout: index - 1 is the newer message (visually below),

commonsUI/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/ui/screen/loggedIn/chats/feed/ChatMessageCompose.kt

@@ -50,6 +50,7 @@ import com.vitorpamplona.amethyst.commons.chats.ui.ChatGroupPosition
 import com.vitorpamplona.amethyst.commons.chats.ui.jumboEmojiCount
 import com.vitorpamplona.amethyst.commons.model.Note
 import com.vitorpamplona.amethyst.commons.model.navigation.routeFor
+import com.vitorpamplona.amethyst.commons.model.privateChats.isSubjectOnlyChatMessage
 import com.vitorpamplona.amethyst.commons.notifications.NotificationContent
 import com.vitorpamplona.amethyst.commons.ui.components.LocalInlineQuoteRenderer
 import com.vitorpamplona.amethyst.commons.ui.navigation.navs.INav
@@ -67,6 +68,7 @@ import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.types.Re
 import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.types.RenderChannelAdminSystemMessage
 import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.types.RenderChatClip
 import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.types.RenderChatRaid
+import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.types.RenderChatSubjectChange
 import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.types.RenderChatZap
 import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.types.RenderConcordTimerNotice
 import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.types.RenderDraftEvent
@@ -178,6 +180,9 @@ fun ChatroomMessageCompose(
             } else if (event is ConcordTimerNoticeEvent) {
                 // Concord kind-1740: "Alice set disappearing messages to 30 days" (CORD-08 §4).
                 RenderConcordTimerNotice(baseNote, accountViewModel, nav)
+            } else if (event?.isSubjectOnlyChatMessage() == true) {
+                // NIP-17 rename with no text: a system line under the subject divider, not an empty bubble.
+                RenderChatSubjectChange(baseNote, innerQuote, accountViewModel, nav)
             } else if (isBuzzActivityRow(event)) {
                 // Buzz agent-job (43xxx) and huddle (48xxx) lifecycle narration. Huddles
                 // especially must be caught here — their content is JSON, not chat text.

commonsUI/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/ui/screen/loggedIn/chats/feed/types/RenderChatSubjectChange.kt

@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2025 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.commons.ui.screen.loggedIn.chats.feed.types
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import com.vitorpamplona.amethyst.commons.chats.ui.ChatSystemMessage
+import com.vitorpamplona.amethyst.commons.model.Note
+import com.vitorpamplona.amethyst.commons.model.navigation.Route
+import com.vitorpamplona.amethyst.commons.model.privateChats.isSubjectOnlyChatMessage
+import com.vitorpamplona.amethyst.commons.resources.Res
+import com.vitorpamplona.amethyst.commons.resources.chat_system_renamed_conversation
+import com.vitorpamplona.amethyst.commons.resources.chat_system_renamed_conversation_to
+import com.vitorpamplona.amethyst.commons.resources.chat_system_renamed_conversation_to_you
+import com.vitorpamplona.amethyst.commons.resources.chat_system_renamed_conversation_you
+import com.vitorpamplona.amethyst.commons.ui.navigation.navs.INav
+import com.vitorpamplona.amethyst.commons.ui.note.UserPicture
+import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.chats.feed.ChatTimeWithDelivery
+import com.vitorpamplona.amethyst.commons.ui.stringRes
+import com.vitorpamplona.amethyst.commons.ui.theme.Size18dp
+import com.vitorpamplona.amethyst.commons.viewmodels.AccountViewModel
+import com.vitorpamplona.quartz.nip14Subject.subject
+import com.vitorpamplona.quartz.nip17Dm.messages.ChatMessageEvent
+
+/**
+ * A rename ([isSubjectOnlyChatMessage]) as a centered system line — "Alice renamed the
+ * conversation" with Alice's avatar — under the subject divider that carries the new name. The
+ * divider alone left an empty bubble below it whose only content was the time.
+ *
+ * Unlike the other system lines this one is a real message with a sender and a delivery, so the
+ * pill keeps the bubble's tappable time and, on our own renames, its relay-acceptance ticks.
+ *
+ * Inside a reply quote there is no divider to name the subject, so the sentence includes it and
+ * the time is dropped, as on any quoted message.
+ */
+@Composable
+fun RenderChatSubjectChange(
+    note: Note,
+    innerQuote: Boolean,
+    accountViewModel: AccountViewModel,
+    nav: INav,
+) {
+    val event = note.event as? ChatMessageEvent ?: return
+    val isLoggedInUser = remember(event.pubKey) { accountViewModel.isLoggedUser(event.pubKey) }
+
+    val text =
+        if (innerQuote) {
+            val subject = remember(event) { event.subject() ?: "" }
+            if (isLoggedInUser) {
+                stringRes(Res.string.chat_system_renamed_conversation_to_you, subject)
+            } else {
+                stringRes(Res.string.chat_system_renamed_conversation_to, observeUserNameByHex(event.pubKey, accountViewModel), subject)
+            }
+        } else {
+            if (isLoggedInUser) {
+                stringRes(Res.string.chat_system_renamed_conversation_you)
+            } else {
+                stringRes(Res.string.chat_system_renamed_conversation, observeUserNameByHex(event.pubKey, accountViewModel))
+            }
+        }
+
+    ChatSystemMessage(
+        text = text,
+        onClick = { nav.nav(Route.Profile(event.pubKey)) },
+        leading = {
+            UserPicture(
+                userHex = event.pubKey,
+                size = Size18dp,
+                accountViewModel = accountViewModel,
+                nav = nav,
+            )
+        },
+        trailing =
+            if (innerQuote) {
+                null
+            } else {
+                { ChatTimeWithDelivery(note, isLoggedInUser, accountViewModel, nav) }
+            },
+    )
+}

commonsUI/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/ui/screen/loggedIn/chats/rooms/ChatroomHeaderCompose.kt

@@ -92,6 +92,8 @@ import com.vitorpamplona.amethyst.commons.resources.channel_invite_row_added_you
 import com.vitorpamplona.amethyst.commons.resources.channel_invite_row_added_you_by
 import com.vitorpamplona.amethyst.commons.resources.chat_preview_decrypting
 import com.vitorpamplona.amethyst.commons.resources.chat_preview_you_prefix
+import com.vitorpamplona.amethyst.commons.resources.chat_system_renamed_conversation_to
+import com.vitorpamplona.amethyst.commons.resources.chat_system_renamed_conversation_to_you
 import com.vitorpamplona.amethyst.commons.resources.concord_direct_invite_from
 import com.vitorpamplona.amethyst.commons.resources.concord_direct_invite_label
 import com.vitorpamplona.amethyst.commons.resources.concord_home_title
@@ -1325,6 +1327,15 @@ private fun RowScope.LastMessagePreview(
                     val sentByMe = lastMessage.author?.pubkeyHex == accountViewModel.account.signer.pubKey
                     if (sentByMe) stringRes(Res.string.chat_preview_you_prefix, preview.text) else preview.text
                 }
+                is ChatPreview.SubjectChange -> {
+                    // A rename with no text has no body to quote; say what it did instead of "You: ".
+                    val authorHex = lastMessage.event?.pubKey
+                    if (authorHex == accountViewModel.account.signer.pubKey) {
+                        stringRes(Res.string.chat_system_renamed_conversation_to_you, preview.subject)
+                    } else {
+                        stringRes(Res.string.chat_system_renamed_conversation_to, observeUserNameByHex(authorHex, accountViewModel), preview.subject)
+                    }
+                }
                 ChatPreview.Decrypting -> stringRes(Res.string.chat_preview_decrypting)
                 ChatPreview.Undecryptable -> stringRes(Res.string.could_not_decrypt_the_message)
                 ChatPreview.Missing -> stringRes(Res.string.referenced_event_not_found)

commonsUI/src/commonTest/kotlin/com/vitorpamplona/amethyst/commons/chats/ui/ChatGroupPositionTest.kt

@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2025 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.commons.chats.ui
+
+import com.vitorpamplona.amethyst.commons.model.AddressableNote
+import com.vitorpamplona.amethyst.commons.model.Note
+import com.vitorpamplona.amethyst.commons.model.User
+import com.vitorpamplona.amethyst.commons.model.UserContext
+import com.vitorpamplona.quartz.nip17Dm.messages.ChatMessageEvent
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+/**
+ * A NIP-17 rename with no text renders as a system line, not a bubble, so it must not join the
+ * author run of the bubbles around it — otherwise the author's next message is drawn as the
+ * continuation of a bubble that isn't there: no author line, and a squared top corner.
+ */
+class ChatGroupPositionTest {
+    private val alice = "a".repeat(64)
+    private val bob = "b".repeat(64)
+    private val context = UserContext { addr -> AddressableNote(addr) }
+
+    private fun message(
+        id: Char,
+        createdAt: Long,
+        content: String,
+        subject: String? = null,
+    ): Note {
+        val tags = listOfNotNull(arrayOf("p", bob), subject?.let { arrayOf("subject", it) }).toTypedArray()
+        val event = ChatMessageEvent(id.toString().repeat(64), alice, createdAt, tags, content, "")
+        return Note(event.id).also { it.loadEvent(event, User(alice, context), emptyList()) }
+    }
+
+    private val start = 1_800_000_000L
+
+    @Test
+    fun messageAfterARenameStartsANewRun() {
+        val rename = message('1', start, content = "", subject = "Weekend plans")
+        val next = message('2', start + 30, content = "hi all")
+        val after = message('3', start + 60, content = "who's in?")
+
+        assertEquals(ChatGroupPosition.SINGLE, computeChatGroupPosition(next, rename, null))
+        assertEquals(ChatGroupPosition.TOP, computeChatGroupPosition(after, next, rename))
+    }
+
+    @Test
+    fun messageBeforeARenameEndsItsRun() {
+        val first = message('1', start, content = "hey")
+        val before = message('2', start + 30, content = "one sec")
+        val rename = message('3', start + 60, content = "", subject = "Weekend plans")
+
+        assertEquals(ChatGroupPosition.BOTTOM, computeChatGroupPosition(rename, before, first))
+    }
+
+    @Test
+    fun renameWithTextStillLeadsTheRunAfterIt() {
+        val rename = message('1', start, content = "new goals", subject = "Weekend plans")
+        val next = message('2', start + 30, content = "hi all")
+
+        assertEquals(ChatGroupPosition.TOP, computeChatGroupPosition(next, rename, null))
+        assertEquals(ChatGroupPosition.BOTTOM, computeChatGroupPosition(null, next, rename))
+    }
+}