Eight files under src/live/:
- constants.ts: throughput-discipline numbers (MAX_TRAIL_LENGTH=200,
reconnect backoff [1s/2s/4s/8s/16s, 30s ceiling], STALE_CONNECTION_MS).
- protocol.ts: zod discriminatedUnion('type', ...) for inbound
(subscribed / unsubscribed / position / error). PositionEntry +
SubscribeResult types per processor-ws-contract.
- connection-store.ts: Zustand store with status state machine.
- position-store.ts: Zustand store with latestByDevice + trailsByDevice
Maps, applySnapshot/applyPositions/clearForEvent/selectDevice
actions. Ring-buffer cap on trails; same-coordinate dedup.
- coalescer.ts: ~30-line rAF coalescer. Per-device buffer; flushes once
per animation frame regardless of receive rate.
- ws-client.ts: state machine (idle / connecting / connected /
reconnecting / closed) with exponential backoff, re-subscribe on
reconnect, stale-connection check, subscribe correlation via
pending-map + 5s timeout. URL resolution helper toAbsoluteWsUrl()
for same-origin path inputs.
- bootstrap.tsx: <LiveBootstrap> creates the client when authenticated,
wires positions through the coalescer to the position store, tears
down on logout. getLiveClient() exposes the singleton for 2.7.
- index.ts: barrel re-exports.
main.tsx wraps <App /> in <LiveBootstrap> alongside <AuthBootstrap>.
Deviations:
1. Skipped the setStatus helper inside createLiveClient; conditional
Parameters<> generics were hostile. Direct
useConnectionStore.getState().setStatus(...) at the ~6 call sites.
2. subscribe() adds to the subscriptions Set even when not connected
(so it replays on reconnect). Caller handles 'not-connected' by
waiting for connection-store status transition.
3. onPosition returns an unsubscribe fn (Set-based). Multi-handler is
free; lets future debug panels/tests attach.
Bundle: src/live/ adds ~15KB raw to the main bundle (mostly zod's
discriminated-union runtime). Total 393KB / 120KB gz.
- pnpm add maplibre-gl + -D @types/geojson.
- src/map/core/styles.ts: defaultStyle (OSM raster bootstrap; 2.2
replaces with the basemap-switcher descriptor table).
- src/map/core/map-view.tsx: module-level Map singleton lazily created
on first <MapView> mount, attached to a class="trm-map-host" detached
<div> that React refs append/remove on mount/unmount. Style-data
lifecycle flips mapReady false on every styledata event, polls
loaded() at 33ms intervals, flips ready true once the style is
loaded — the canonical MapLibre style-swap dance.
- Exports getMap()/getMapReady()/subscribeMapReady()/useMapReady (via
useSyncExternalStore for SSR-safe + concurrent-safe reads). getMap()
throws if called pre-mount; the explicit failure mode beats a
null-able top-level export.
- src/routes/_authed/monitor.tsx: new /monitor route, full-viewport
<MapView /> for 2.1 (no children — subsequent tasks plug in here).
- src/routes/_authed/index.tsx: home-page card now links to /monitor.
- eslint.config.js: override for src/map/** + src/live/** disables
react-refresh/only-export-components. Same pattern as the existing
overrides for shadcn primitives and route files.
Deviation: spec sketched a top-level `map` constant export; implemented
as `getMap(): MapLibreMap` (a function) so the singleton stays lazy
until <MapView> mounts. Top-level constant would either force eager
init (breaks SSR/tests) or be nullable (footgun). The function form
throws a clear error if called pre-mount.
Bundle: /monitor lazy chunk is 1MB raw / 274KB gzipped (MapLibre + CSS).
Other routes unaffected. Vite chunk-size warning is harmless.
Nine task files matching Phase 1's shape (Goal / Deliverables / Spec /
Acceptance / Risks / Done). README updated with full sequencing diagram,
files-modified outline, tech stack additions, design rules, and phase
acceptance.
| # | Task |
| --- | --------------------------------------------------------------------- |
| 2.1 | MapView singleton + mapReady gate |
| 2.2 | Tile-source switcher (Esri / OpenTopoMap / OSM / optional Google) |
| 2.3 | Sprite preload — 7 racing categories x 4 colour variants |
| 2.4 | WS client + rAF coalescer + Zustand position store + connection store |
| 2.5 | MapPositions — clustered + selected sources |
| 2.6 | MapTrails — bounded ring buffer, polyline rendering |
| 2.7 | Event picker — TanStack Query + WS subscription orchestration |
| 2.8 | Camera control trio — default-fit / selected-follow / one-shot |
| 2.9 | Connection status + per-device last-seen indicators |
Sequencing: 2.1 and 2.4 are parallel foundations (singleton vs data
pipeline). Once both land, 2.5 / 2.6 / 2.7 / 2.9 fan out independently.
2.2 / 2.3 only need 2.1. 2.8 sits at the end on top of 2.1 + 2.5.
Each task documents its deliverables down to file paths + interface
shapes, includes concrete code sketches in the Specification, lists
explicit out-of-scope items, and surfaces risks for the implementer
to think about. An agent (or future me) can pick up any single task
and ship it without re-deriving the design from the wiki.
Resolved Phase 2 design decisions baked into the task files:
- Trails: flat-colour-per-device for v1, defer speed-coloured segments
to a Phase 3 polish task.
- Cluster params: 14/50 (traccar default); tune after seeing real data.
- Event picker placement: top-left dropdown.
- Multi-event: out — single-select, one event at a time.
- Stale-position visual: fade icon opacity; defer warning badges.
julian