Zepp OS: send real coordinates in v5 place response

The v5 place dataset hard-coded latitude/longitude to "0.0" and used a
constant locationKey "accu:123456", which prevented watches that were
never provisioned via the official Zepp app (Bip 6, Active 2, ...) from
accepting the response as authoritative — they treated the zero coords
as a missing-location signal and silently refused to display weather
(issue #5653).

- ZeppOsWeatherHandlerV5.createPlace: pull lat/lon from WeatherSpec
  when set, else fall back to the user-configured location pref. Format
  with Locale.ROOT and derive a stable per-location locationKey from a
  hash of the coords so the watch can dedupe responses.

- ZeppOsWeatherService.onSendWeather: same fallback chain for the
  CMD_SET_DEFAULT_LOCATION packet so the watch's default-location state
  is bootstrapped with real coordinates instead of "1.234,-5.678".

Refs #5653.

source: https://github.com/PeterXMR/Gadgetbridge

(cherry picked from commit be87ac3364fbf5725f43e3dbac87ef2e103fdd89)

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huami/zeppos/services/ZeppOsWeatherService.java

@@ -21,7 +21,9 @@ import org.slf4j.LoggerFactory;
 
 import java.io.ByteArrayOutputStream;
 import java.nio.charset.StandardCharsets;
+import java.util.Locale;
 
+import nodomain.freeyourgadget.gadgetbridge.GBApplication;
 import nodomain.freeyourgadget.gadgetbridge.model.WeatherSpec;
 import nodomain.freeyourgadget.gadgetbridge.model.weather.Weather;
 import nodomain.freeyourgadget.gadgetbridge.service.devices.huami.zeppos.AbstractZeppOsService;
@@ -67,7 +69,18 @@ public class ZeppOsWeatherService extends AbstractZeppOsService {
         // When we have a weather update, set the default location to that location on the band.
         // TODO: Support for multiple weather locations
 
-        final String locationKey = "1.234,-5.678,xiaomi_accu:" + System.currentTimeMillis(); // dummy
+        float lat = weatherSpec.getLatitude();
+        float lon = weatherSpec.getLongitude();
+        if (lat == 0f && lon == 0f) {
+            // Some weather providers don't populate WeatherSpec coords on broadcast.
+            // Fall back to user-configured location pref so the watch gets a valid
+            // default location and accepts subsequent v5 HTTP responses (issue #5653).
+            lat = GBApplication.getPrefs().getFloat("location_latitude", 0f);
+            lon = GBApplication.getPrefs().getFloat("location_longitude", 0f);
+        }
+        final String coordKey = String.format(Locale.ROOT, "%.4f,%.4f", lat, lon);
+        final long locationKeyId = ((long) coordKey.hashCode()) & 0xFFFFFFFFL;
+        final String locationKey = String.format(Locale.ROOT, "%.4f,%.4f,xiaomi_accu:%d", lat, lon, locationKeyId);
         final String locationName = weatherSpec.getLocation();
 
         try {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huami/zeppos/services/http/ZeppOsWeatherHandlerV5.kt

@@ -3,6 +3,7 @@ package nodomain.freeyourgadget.gadgetbridge.service.devices.huami.zeppos.servic
 import com.google.gson.Gson
 import com.google.gson.GsonBuilder
 import com.google.gson.JsonObject
+import nodomain.freeyourgadget.gadgetbridge.GBApplication
 import nodomain.freeyourgadget.gadgetbridge.model.WeatherSpec
 import nodomain.freeyourgadget.gadgetbridge.model.weather.Weather.getWeatherSpec
 import nodomain.freeyourgadget.gadgetbridge.service.devices.huami.zeppos.ZeppOsWeatherHandler
@@ -18,6 +19,7 @@ import java.time.ZoneId
 import java.util.Calendar
 import java.util.Date
 import java.util.GregorianCalendar
+import java.util.Locale
 import kotlin.math.roundToInt
 
 @Suppress("unused")
@@ -88,14 +90,32 @@ object ZeppOsWeatherHandlerV5 {
         version = 1,
     )
 
-    private fun createPlace(weatherSpec: WeatherSpec) = Place(
-        locationKey = "accu:123456",
-        longitude = weatherSpec.longitude.toString(),
-        latitude = weatherSpec.latitude.toString(),
-        affiliation = weatherSpec.location,
-        name = weatherSpec.location,
-        countryCode = null,
-    )
+    private fun createPlace(weatherSpec: WeatherSpec): Place {
+        val (lat, lon) = resolveCoordinates(weatherSpec)
+        // Stable per-location id so the watch can dedupe responses. Hash of rounded
+        // coords keeps it deterministic across requests for the same location.
+        val coordKey = String.format(Locale.ROOT, "%.4f,%.4f", lat, lon)
+        val locationKeyId = coordKey.hashCode().toLong() and 0xFFFFFFFFL
+        return Place(
+            locationKey = "accu:$locationKeyId",
+            longitude = String.format(Locale.ROOT, "%.3f", lon),
+            latitude = String.format(Locale.ROOT, "%.3f", lat),
+            affiliation = weatherSpec.location,
+            name = weatherSpec.location,
+            countryCode = null,
+        )
+    }
+
+    // Some weather providers don't populate WeatherSpec.latitude/longitude on broadcast.
+    // Fall back to the user-configured location pref so the watch gets a non-zero place,
+    // which it requires to accept the response as authoritative (issue #5653).
+    private fun resolveCoordinates(weatherSpec: WeatherSpec): Pair<Float, Float> {
+        if (weatherSpec.latitude != 0f || weatherSpec.longitude != 0f) {
+            return weatherSpec.latitude to weatherSpec.longitude
+        }
+        val prefs = GBApplication.getPrefs()
+        return prefs.getFloat("location_latitude", 0f) to prefs.getFloat("location_longitude", 0f)
+    }
 
     private fun createHourlyWeather(weatherSpec: WeatherSpec): HourlyWeather {
         return HourlyWeather(