App 2.10.1: show negative usage while recuperating

Net regeneration over the window (or the trip) used to hide both
estimates behind "needs a few minutes of driving". It is a real
reading: the usage now shows as negative kWh/100 km, and the range as
"> 999 km" with "while recuperating" beneath it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QLJfZQZeAKAwSqViTmLzki

app/src/main/java/com/evsuite/abrp/MainActivity.java

@@ -1041,7 +1041,7 @@ public class MainActivity extends AppCompatActivity {
         // Coasting at speed costs almost nothing, which would read as thousands of km.
         range.setText(e.rangeKm > 999 ? getString(R.string.range_over, 999)
                 : String.format(java.util.Locale.US, "%.0f km", e.rangeKm));
-        rangeNote.setText("");
+        rangeNote.setText(e.kwhPer100Km <= 0 ? getString(R.string.range_recuperating) : "");
         usage.setText(getString(R.string.range_consumption, e.kwhPer100Km));
         usageNote.setText(basis);
     }

app/src/main/java/com/evsuite/abrp/RangeEstimator.java

@@ -15,8 +15,8 @@ import java.util.Iterator;
  * a new trip; so does charging.
  *
  * Remaining energy is SOC x usable capacity: the car publishes no pack energy, so the capacity
- * is a setting. Every estimate is null when it cannot mean anything — standing still,
- * regenerating, too little data — rather than a misleading number.
+ * is a setting. An estimate is null when it cannot mean anything — not moved yet, too little
+ * data — rather than a misleading number. Net regeneration is shown as it is: negative usage.
  *
  * Fed by both the service tick (15 s) and the open Vehicle page (2 s); the integration is
  * time-weighted, so the two rates mix correctly. Times are on the monotonic clock
@@ -112,9 +112,8 @@ final class RangeEstimator {
 
     /** Range at the consumption since start; null until the trip has some distance behind it. */
     synchronized Estimate sinceStart(Double remainingKwh) {
-        if (remainingKwh == null || tripDistanceKm < MIN_DISTANCE_KM || tripEnergyKwh <= 0) return null;
-        double kwhPerKm = tripEnergyKwh / tripDistanceKm;
-        return new Estimate(remainingKwh / kwhPerKm, kwhPerKm * 100, tripDistanceKm);
+        if (remainingKwh == null || tripDistanceKm < MIN_DISTANCE_KM) return null;
+        return estimate(remainingKwh, tripEnergyKwh, tripDistanceKm);
     }
 
     synchronized Estimate average(Double remainingKwh, long nowMs) {
@@ -136,9 +135,18 @@ final class RangeEstimator {
             }
             previous = s;
         }
-        if (covered < MIN_WINDOW_MS || distanceKm < MIN_DISTANCE_KM || energyKwh <= 0) return null;
+        if (covered < MIN_WINDOW_MS || distanceKm < MIN_DISTANCE_KM) return null;
+        return estimate(remainingKwh, energyKwh, distanceKm);
+    }
+
+    /**
+     * Net regeneration (downhill, recuperating) is a real reading: the usage is negative, and
+     * the range is unbounded rather than negative.
+     */
+    private static Estimate estimate(double remainingKwh, double energyKwh, double distanceKm) {
         double kwhPerKm = energyKwh / distanceKm;
-        return new Estimate(remainingKwh / kwhPerKm, kwhPerKm * 100, distanceKm);
+        double rangeKm = kwhPerKm > 0 ? remainingKwh / kwhPerKm : Double.POSITIVE_INFINITY;
+        return new Estimate(rangeKm, kwhPerKm * 100, distanceKm);
     }
 
     synchronized void clear() {

app/src/main/res/values/strings.xml

@@ -38,6 +38,7 @@
     <string name="range_consumption">%1$.1f kWh/100 km</string>
     <string name="range_over">&gt; %1$d km</string>
     <string name="range_waiting">needs a few minutes of driving</string>
+    <string name="range_recuperating">while recuperating</string>
     <string name="range_trip_waiting">once the car has moved</string>
     <string name="usage_over_distance">over %1$.1f km</string>
     <string name="usage_last_5_min">over the last 5 minutes</string>

app/src/test/java/com/evsuite/abrp/RangeEstimatorTest.java

@@ -110,6 +110,9 @@ public class RangeEstimatorTest {
 
         RangeEstimator downhill = new RangeEstimator();
         for (long t = 0; t <= 240_000; t += 2_000) downhill.add(t, -5f, 80f);
-        assertNull("net regeneration", downhill.average(25.4, 240_000));
+        RangeEstimator.Estimate regen = downhill.average(25.4, 240_000);
+        assertNotNull("net regeneration is a reading", regen);
+        assertEquals(-6.25, regen.kwhPer100Km, 0.01);
+        assertTrue(Double.isInfinite(regen.rangeKm));
     }
 }