1 files changed, 58 insertions, 0 deletions
diff --git a/jb-ui/src/models/grlEventsSlice.ts b/jb-ui/src/models/grlEventsSlice.ts
new file mode 100644
index 0000000..912c4ca
--- /dev/null
+++ b/jb-ui/src/models/grlEventsSlice.ts
@@ -0,0 +1,58 @@
+import { EventEnvelope } from "@/api_fsb";
+import { RootState } from "@/store";
+import { createEntityAdapter, createSelector, createSlice } from '@reduxjs/toolkit';
+
+const eventAdapter = createEntityAdapter({
+    selectId: (model: EventEnvelope) => model.event_uuid!,
+    sortComparer: (a, b) => {
+        // ASC by timestamp
+        return a.timestamp!.localeCompare(b.timestamp!);
+    },
+});
+
+
+const grlEventsSlice = createSlice({
+    name: 'grlEvents',
+    initialState: eventAdapter.getInitialState(),
+
+    reducers: {
+        addEvent: eventAdapter.addOne,
+        addEvents: eventAdapter.addMany,
+        upsertEvent: eventAdapter.upsertOne,  // Add or Update
+
+    }
+})
+
+
+export const {
+    addEvent, addEvents, upsertEvent
+} = grlEventsSlice.actions;
+
+
+export const eventSelectors = eventAdapter.getSelectors(
+    (state: RootState) => state.events
+);
+
+export const selectAllEvents = (state: RootState): EventEnvelope[] => eventSelectors.selectAll(state);
+
+const BASE_SPEED = 40;  // px/sec at idle
+const MAX_SPEED = 380;  // px/sec at surge
+
+const RATE_WINDOW_MS = 10_000;  // ms window to measure message frequency
+const RATE_TO_SPEED = 55;  // px/sec added per msg/sec
+
+
+// --- Speed: derived from arrival rate of recent items --- 
+export const selectCurrentSpeed = createSelector(selectAllEvents, (items) => {
+    const now = Date.now();
+
+    const recentCount = items.filter((m) => {
+        const ts = new Date(m.timestamp!).getTime();
+        return now - ts < RATE_WINDOW_MS;
+    }).length;
+
+    const rate = recentCount / (RATE_WINDOW_MS / 1_000);  // msgs/sec
+    return Math.min(BASE_SPEED + rate * RATE_TO_SPEED, MAX_SPEED);
+});
+
+export default grlEventsSlice.reducer