feat(track): wire NMEA wind data into GPS track pointsHEADmaster

MainViewModel caches the latest WindData from LocationService.nmeaWindDataFlow
via updateWind(). addGpsPoint() populates TrackPoint wind fields from the cache,
defaulting to zero if no NMEA wind sentence has arrived yet.

MainActivity.observeDataSources() feeds LocationService.nmeaWindDataFlow
into viewModel.updateWind() alongside the existing GPS and anchor observers.

3 new unit tests in MainViewModelWindTest verify zero-default, wind capture,
and mid-track wind update behaviour.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 58 insertions, 0 deletions

diff --git a/android-app/app/src/test/kotlin/org/terst/nav/ui/MainViewModelWindTest.kt b/android-app/app/src/test/kotlin/org/terst/nav/ui/MainViewModelWindTest.kt
new file mode 100644
index 0000000..8e7125c
--- /dev/null
+++ b/android-app/app/src/test/kotlin/org/terst/nav/ui/MainViewModelWindTest.kt
@@ -0,0 +1,58 @@
+package org.terst.nav.ui
+
+import androidx.arch.core.executor.testing.InstantTaskExecutorRule
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
+import kotlinx.coroutines.test.resetMain
+import kotlinx.coroutines.test.runTest
+import kotlinx.coroutines.test.setMain
+import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.terst.nav.sensors.WindData
+import org.terst.nav.ui.MainViewModel
+
+@OptIn(ExperimentalCoroutinesApi::class)
+class MainViewModelWindTest {
+
+    @get:Rule val instantTask = InstantTaskExecutorRule()
+    private val dispatcher = UnconfinedTestDispatcher()
+
+    @Before fun setUp() { Dispatchers.setMain(dispatcher) }
+    @After fun tearDown() { Dispatchers.resetMain() }
+
+    @Test fun `addGpsPoint uses zero wind when no wind update received`() = runTest {
+        val vm = MainViewModel()
+        vm.startTrack()
+        vm.addGpsPoint(37.0, -122.0, 5.0, 90.0)
+        val pt = vm.trackPoints.value.first()
+        assertEquals(0.0, pt.windSpeedKnots, 0.001)
+        assertEquals(0.0, pt.windAngleDeg, 0.001)
+        assertEquals(false, pt.isTrueWind)
+    }
+
+    @Test fun `addGpsPoint uses latest wind data after updateWind`() = runTest {
+        val vm = MainViewModel()
+        vm.updateWind(WindData(windAngle = 45.0, windSpeed = 15.5, isTrueWind = true, timestampMs = 1000L))
+        vm.startTrack()
+        vm.addGpsPoint(37.0, -122.0, 5.0, 90.0)
+        val pt = vm.trackPoints.value.first()
+        assertEquals(15.5, pt.windSpeedKnots, 0.001)
+        assertEquals(45.0, pt.windAngleDeg, 0.001)
+        assertEquals(true, pt.isTrueWind)
+    }
+
+    @Test fun `addGpsPoint reflects wind update between fixes`() = runTest {
+        val vm = MainViewModel()
+        vm.startTrack()
+        vm.addGpsPoint(37.0, -122.0, 5.0, 90.0)
+        vm.updateWind(WindData(windAngle = 180.0, windSpeed = 8.0, isTrueWind = false, timestampMs = 2000L))
+        vm.addGpsPoint(37.1, -122.0, 5.0, 90.0)
+        val pts = vm.trackPoints.value
+        assertEquals(0.0, pts[0].windSpeedKnots, 0.001)
+        assertEquals(8.0, pts[1].windSpeedKnots, 0.001)
+    }
+}