13 Messaging Timeline Composer and Inbox

13 — Messaging Timeline, Composer & Inbox

Corresponding Specifications: sys-arch/ui-ux-04-conversation-list-inbox-architecture.md, sys-arch/ui-ux-05-conversation-message-timeline-architecture.md, sys-arch/ui-ux-06-message-composer-attachments-voice-notes-drafts-architecture.md
Key Crates: crates/siar-ui-state, crates/siar-messaging

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1. Inbox & Conversation List Architecture

The SIAR inbox indexes direct 1-on-1 chats, MLS encrypted groups, and emergency broadcast feeds:

+-------------------------------------------------------------------------------+
| [Search Conversations / Transports]                      [+ New Chat / Group] |
+-------------------------------------------------------------------------------+
| [*] Emergency SOS Alert Hub     (3 active broadcasts nearby)      [12:42] (3) |
| [o] Alice Smith                 [BLE Direct] Hey, are you safe?   [12:40] (1) |
| [o] Field Rescue Team Bravo     [Mesh Mule] Checkpoint B reached  [12:35]     |
| [ ] Charlie (Offline)           [DTN Spray] Voice note (0:42)     [11:15]     |
| [ ] Logistics & Supply Channel  [LAN Relay] Supplies in route     [Yesterday] |
+-------------------------------------------------------------------------------+

Transport Path Badges

Every conversation item displays real-time transport route indicators:

• 🟢 Direct Local: Connected over sub-10ms BLE, Wi-Fi Direct, or LAN.
• 🟡 Multi-Hop Mesh: Reachable via intermediate peer hops ($N$ hops away).
• 🟣 DTN Mule Transit: Message carried asynchronously by moving mules.
• 🔵 Internet Relay: Reachable over encrypted Iroh/QUIC cloud tunnel.

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2. Virtualized Message Timeline

To render timelines with $> 500,000$ messages smoothly at 60–120 fps with negligible memory consumption, SIAR uses a virtualized reverse windowing model:

graph TD
    DB[Stoolap Message Table] -->|Chunk Query: LIMIT 50 OFFSET N| Cache[In-Memory Message Cache]
    Cache --> DiffEngine[Timeline Diff Engine]
    DiffEngine --> VirtualList[Virtualized Reverse Scroll Container]
    VirtualList --> RenderBubble[Message Bubble Component]

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Delivery Status Indicators

Visual Glyph	Meaning	Underlying Engine State
🕒	Pending	Queued in local outbox, awaiting physical radio link
⬆️	Transmitting	Actively sending fragments over radio driver
🎒	Mule Carried	Transferred to trusted DTN carrier node
✓	Sent / Stored	Delivered to direct peer or mesh gateway
✓✓	Delivered	Reached recipient device and committed to storage
👁️ (Blue)	Read	Recipient has rendered conversation view
⚠️	Failed	Hop limit exceeded or cryptographic verification error

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3. Message Composer & Voice Notes

The composer subsystem provides rich multimodal interaction with instant local feedback:

+-------------------------------------------------------------------------------+
| [ + Attachment ] [ Type encrypted message...                      ] [ 🎤 Hold ]|
+-------------------------------------------------------------------------------+
| Draft auto-saved • Enter to Send • Shift+Enter for New Line • Max size: 50 MB |
+-------------------------------------------------------------------------------+

Voice Note Recording Pipeline

1. Low-Latency Capture: High-definition microphone audio capture at 48 kHz.
2. Realtime Waveform Preview: Calculates 60-band audio energy levels every 20ms for dynamic visual waveform rendering.
3. On-the-Fly Opus Compression: Encodes directly to Opus bitstream during recording, eliminating post-recording compression delays.
4. Instant Encryption: Encrypts and enqueues the resulting blob manifest the moment the user releases the record button.