From c68f167acb5b20c692aa0632b5de48c446b05e40 Mon Sep 17 00:00:00 2001
From: German Khokhlov <ouchlock@gmail.com>
Date: Tue, 3 Nov 2026 15:07:00 +0400
Subject: [PATCH] fix(transit): count distinct coverage regions

---
 src/layers/transit/queries.js       |  7 ++++++-
 src/layers/transit/queries.test.mjs | 28 ++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 src/layers/transit/queries.test.mjs

diff --git a/src/layers/transit/queries.js b/src/layers/transit/queries.js
index b86613160..dc3ea4d79 100644
--- a/src/layers/transit/queries.js
+++ b/src/layers/transit/queries.js
@@ -12,6 +12,11 @@ import {
 } from '../../data/transitFeeds.js';
 import { transitModeTier } from '../../data/transitPresetStyle.js';
 
+/** Regions, not feeds: one region can carry several feeds (Rio has two). */
+const TRANSIT_REGION_COUNT = new Set(
+  TRANSIT_ENABLED_FEEDS.map((feed) => feed.region),
+).size;
+
 /**
  * The registry entry behind a vehicle. Live feeds answer first so a feed the
  * session disabled stops supplying vocabulary; the registry is the fallback,
@@ -249,7 +254,7 @@ export function createQueries({ state, parts }) {
           // English data (the analyst's empty note to the model); the voice
           // card shows it through NOTE_PATTERNS (voice/resultDisplay.js).
           coverage: state._altitudeGateOpen
-            ? `No feed here yet · ${TRANSIT_ENABLED_FEEDS.length} regions available`
+            ? `No feed here yet · ${TRANSIT_REGION_COUNT} regions available`
             : `Fly below ${Math.round(ACTIVATION_ALTITUDE_M / 1000).toLocaleString('en-US')} km to a covered region`,
         };
       }
diff --git a/src/layers/transit/queries.test.mjs b/src/layers/transit/queries.test.mjs
new file mode 100644
index 000000000..a7ac1224c
--- /dev/null
+++ b/src/layers/transit/queries.test.mjs
@@ -0,0 +1,28 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { createQueries } from './queries.js';
+import { TRANSIT_ENABLED_FEEDS } from '../../data/transitFeeds.js';
+
+test('the empty-coverage note counts regions, not feeds', () => {
+  const rio = TRANSIT_ENABLED_FEEDS.filter(
+    (feed) => feed.region === 'Rio de Janeiro, RJ',
+  );
+  assert.equal(rio.length, 2, 'Rio is one region with two feeds');
+  const regions = new Set(TRANSIT_ENABLED_FEEDS.map((feed) => feed.region));
+  assert.ok(regions.size < TRANSIT_ENABLED_FEEDS.length);
+
+  const stats = createQueries({
+    state: {
+      _activeFeeds: new Map(),
+      _vehicles: new Map(),
+      _enabled: true,
+      _altitudeGateOpen: true,
+    },
+    parts: {},
+  }).methods.getStats();
+  assert.equal(stats.status, 'zoom-in');
+  assert.equal(
+    stats.coverage,
+    `No feed here yet · ${regions.size} regions available`,
+  );
+});