Session Routing Rewrite

The Rule

One function. One rule.

getSessionTarget(sessionId) → div[data-session=X]

Every event has a session ID. Every session has a div. Event comes in → has session ID → find the div → put content there. No botId. No domain. No active session comparison. No hide/show filtering. The div might be hidden (viewing different session). Content still goes in. When user switches to that session, everything is already there.

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state.ts — The Router

• Rewrite getSessionTarget() (line 136)
  • Takes ONLY sessionId
  • document.querySelector('.session-messages[data-session=X]')
  • If div doesn't exist → create it (hidden, inside bot container)
  • No botId param, no domain param, no fallback to active session lookup
  • Kill getActiveChatSessionId() fallback inside this function

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render.ts — addMessage

• addMessage() (line 454)
  • Accept sessionId param (already partially done)
  • Call getSessionTarget(sessionId) — not getSessionTarget(domain)
  • Every caller must pass sessionId

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message-list.ts — renderMessages + tool events

• renderMessages() (line 262)

  • Caller must pass sessionId
  • Route to getSessionTarget(sessionId)

• handleToolEvent() (line 1035)

  • Already extracts toolCsId from event.sessionKey
  • Pass to getSessionTarget(toolCsId) — not getSessionTarget(activeBotId, toolCsId)

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chat-events.ts — Delta/final/error streaming

• Remove active session skip block (line 182-208)

  • Currently: if eventSessionKey !== activeSessionKey → skip rendering
  • New: route to getSessionTarget(sessionId) always. Content goes to its div.
  • Keep the unread badge increment for background sessions

• Guest session handler (line 135)

  • Route to session div

• Delta typing repositioning (line 303)

  • Use getSessionTarget(sessionId) from payload

• Final cleanup (line 449)

  • Use getSessionTarget(sessionId) from payload

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main.ts — SSE event handlers

• queue:sent handler (line 567)

  • Route to session div using event's sessionId

• new_message handler (line 669-679)

  • Remove "div doesn't exist? skip" logic
  • Get sessionId from event.chatSessionId
  • Pass sessionId to addMessage()
  • Content goes to session div, whether visible or not

• Tool event session filter (line 501-506)

  • Already removed skip logic (content goes to div)
  • Typing label update: only for active session (cosmetic, not content routing)

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typing.ts — Typing indicators (8 call sites)

• showTyping() (line 23) — route to session div
• showTyping() fallback (line 70) — route to session div
• hideTyping() (line 131) — route to session div
• Hook typing show (line 170) — route to session div
• Hook typing hide (line 182) — route to session div
• Hook message show (line 194) — route to session div
• Hook message update (line 210) — route to session div
• Finalize hook response (line 225) — route to session div

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history.ts — History loading

• Warm target check (line 118) — use session div
• Load older messages container (line 451) — use session div
• Scroll sentinel setup (line 750) — use session div
• Scroll load handler (line 798) — use session div

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spawn-bubbles.ts — CS spawn UI (4 call sites)

• renderSpawnBubble() (line 64) — route to session div
• updateSpawnBubble() (line 119) — route to session div
• completeSpawnBubble() (line 233) — route to session div
• Active container in complete (line 289) — route to session div

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messaging.ts — Send + queue

• Send message optimistic render (line 348) — route to session div
• Queue dock legacy cleanup (line 561) — route to session div
• Queue sent render (line 931) — route to session div
• Queue dock filter by active session (already done)

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sessions.ts — Working state

• Context usage bar container (line 36) — route to session div

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tasks-sidebar.ts — Task UI

• Task complete render (line 167) — route to session div
• Task action render (line 288) — route to session div

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ui.ts — Bot switching

• Empty state check (line 770) — route to session div
• Bot switch scroll restore (line 2752) — route to session div

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Server side (already done, needs restart)

• message-capture.ts:669 — chatSessionId in new_message SSE event
• message-capture.ts:835 — chatSessionId in hook new_message SSE event
• relay.ts:211 — chatSessionId in relay new_message SSE event
• bot-state.ts — isSessionWorking() for per-session working check
• message-queue.ts:39 — use isSessionWorking instead of isBotWorking

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Other (already done)

• Scroll position save/restore per session in showSessionContainer
• Queue dock filters by active session ID

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Deploy

• Restart GATE server (pm2 restart gate)
• Build chat bundle (bun run build:chat)
• Verify: send message to session 301 while viewing 305 → goes to 301's div
• Verify: tool events for session 305 → go to 305's div, not current view
• Verify: switch sessions → scroll position preserved
• Verify: queue dock only shows items for active session

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Summary

34 frontend changes across 11 files. 5 server changes done. 1 restart.

One function. One rule. Session ID in, div out.