From 93c5330917663c4b91542dcc0bfaaa4983d3b97a Mon Sep 17 00:00:00 2001
From: Eli Mallon <eli@iame.li>
Date: Tue, 29 Sep 2026 13:52:26 -0700
Subject: [PATCH] Fix duplicate teleport announcements

---
 js/components/src/lib/system-messages.ts      | 15 +++++++++++--
 js/core/src/lib/system-messages.ts            | 17 ++++++++++----
 .../websocket-consumer.test.ts                | 22 +++++++++++++++++++
 .../livestream-store/websocket-consumer.ts    |  1 +
 4 files changed, 49 insertions(+), 6 deletions(-)

diff --git a/js/components/src/lib/system-messages.ts b/js/components/src/lib/system-messages.ts
index 5744d8df3..b6cae529f 100644
--- a/js/components/src/lib/system-messages.ts
+++ b/js/components/src/lib/system-messages.ts
@@ -81,7 +81,8 @@ export const SystemMessages = {
     streamerName: string,
     streamerDid: string,
     count: number,
-    chatProfile?: any,
+    chatProfile?: ChatMessageViewHydrated["chatProfile"],
+    teleportUri?: string,
   ): ChatMessageViewHydrated => {
     const text =
       count > 0
@@ -92,6 +93,16 @@ export const SystemMessages = {
       count,
     });
 
+    // The live event and the target stream's initial burst can both carry the
+    // same arrival. Use the teleport record as the message identity so chat
+    // reducer deduplication keeps only one announcement.
+    if (teleportUri) {
+      const id = encodeURIComponent(teleportUri);
+      message.uri =
+        `at://did:sys:system/place.stream.chat.message/teleport-${id}` as ChatMessageViewHydrated["uri"];
+      message.cid = `system-teleport-${id}` as ChatMessageViewHydrated["cid"];
+    }
+
     // create a mention facet for the streamer name so it gets colored using existing mention rendering
     if (chatProfile && streamerDid) {
       const nameStart = text.indexOf(streamerName);
@@ -110,7 +121,7 @@ export const SystemMessages = {
           features: [
             {
               $type: "app.bsky.richtext.facet#mention",
-              did: streamerDid as any,
+              did: streamerDid as ChatMessageViewHydrated["author"]["did"],
             },
           ],
         },
diff --git a/js/core/src/lib/system-messages.ts b/js/core/src/lib/system-messages.ts
index 15502b0cc..2045d7d06 100644
--- a/js/core/src/lib/system-messages.ts
+++ b/js/core/src/lib/system-messages.ts
@@ -81,7 +81,8 @@ export const SystemMessages = {
     streamerName: string,
     streamerDid: string,
     count: number,
-    chatProfile?: any,
+    chatProfile?: ChatMessageViewHydrated["chatProfile"],
+    teleportUri?: string,
   ): ChatMessageViewHydrated => {
     const text =
       count > 0
@@ -92,15 +93,23 @@ export const SystemMessages = {
       count,
     });
 
+    // The live event and the target stream's initial burst can both carry the
+    // same arrival. Use the teleport record as the message identity so chat
+    // reducer deduplication keeps only one announcement.
+    if (teleportUri) {
+      const id = encodeURIComponent(teleportUri);
+      message.uri =
+        `at://did:sys:system/place.stream.chat.message/teleport-${id}` as ChatMessageViewHydrated["uri"];
+      message.cid = `system-teleport-${id}` as ChatMessageViewHydrated["cid"];
+    }
+
     // create a mention facet for the streamer name so it gets colored using existing mention rendering
     if (chatProfile && streamerDid) {
       const nameStart = text.indexOf(streamerName);
-
       // encode byte positions
       const encoder = new TextEncoder();
       const byteStart = encoder.encode(text.substring(0, nameStart)).length;
       const byteEnd = byteStart + encoder.encode(streamerName).length;
-
       message.record.facets = [
         {
           index: {
@@ -110,7 +119,7 @@ export const SystemMessages = {
           features: [
             {
               $type: "app.bsky.richtext.facet#mention",
-              did: streamerDid as any,
+              did: streamerDid as ChatMessageViewHydrated["author"]["did"],
             },
           ],
         },
diff --git a/js/core/src/livestream-store/websocket-consumer.test.ts b/js/core/src/livestream-store/websocket-consumer.test.ts
index 719d47081..e4028cbab 100644
--- a/js/core/src/livestream-store/websocket-consumer.test.ts
+++ b/js/core/src/livestream-store/websocket-consumer.test.ts
@@ -281,4 +281,26 @@ describe("handleWebSocketMessages: teleport records", () => {
 
     expect(result.activeTeleport).toEqual(teleport);
   });
+
+  it("deduplicates live and initial-burst teleport arrivals", () => {
+    const arrival = {
+      $type: "place.stream.livestream#teleportArrival",
+      teleportUri:
+        "at://did:plc:source/place.stream.live.teleport/3lteleport0001",
+      source: {
+        did: "did:plc:source",
+        handle: "source.example.com",
+      },
+      viewerCount: 15,
+      startsAt: "2026-09-25T12:00:00.000Z",
+    };
+
+    const result = handleWebSocketMessages(makeState(), [
+      arrival,
+      { ...arrival, viewerCount: 12 },
+    ]);
+
+    expect(result.chat).toHaveLength(1);
+    expect(result.chat[0].record.text).toContain("15 viewers teleported");
+  });
 });
diff --git a/js/core/src/livestream-store/websocket-consumer.ts b/js/core/src/livestream-store/websocket-consumer.ts
index fc3a6adf5..a88dc93d0 100644
--- a/js/core/src/livestream-store/websocket-consumer.ts
+++ b/js/core/src/livestream-store/websocket-consumer.ts
@@ -278,6 +278,7 @@ export const handleWebSocketMessages = (
           arrival.source.did,
           arrival.viewerCount,
           arrival.chatProfile,
+          arrival.teleportUri,
         );
         // set proper times
         systemMessage.indexedAt = arrival.startsAt;
-- 
knotmirror 0.0.1