From 7ad1a25e8ee6580c83063275102703ed17912389 Mon Sep 17 00:00:00 2001
From: lingniu <lingniu@lingnius-Mac-mini.local>
Date: Thu, 2 Jul 2026 01:04:14 +0800
Subject: [PATCH] fix: normalize yutong mqtt mileage units

---
 .../internal/protocol/yutongmqtt/parser.go      | 17 ++++++++++++++++-
 .../internal/protocol/yutongmqtt/parser_test.go | 16 ++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/go/vehicle-gateway/internal/protocol/yutongmqtt/parser.go b/go/vehicle-gateway/internal/protocol/yutongmqtt/parser.go
index 9eff6fb5..09f1f822 100644
--- a/go/vehicle-gateway/internal/protocol/yutongmqtt/parser.go
+++ b/go/vehicle-gateway/internal/protocol/yutongmqtt/parser.go
@@ -69,7 +69,7 @@ func fieldsFromData(data map[string]any) map[string]any {
 		fields[envelope.FieldSpeedKMH] = speed
 	}
 	if mileage, ok := firstFloat(data, "TOTAL_MILEAGE", "totalMileage", "total_mileage_km"); ok {
-		fields[envelope.FieldTotalMileageKM] = mileage
+		fields[envelope.FieldTotalMileageKM] = normalizeTotalMileageKM(mileage)
 	}
 	if soc, ok := firstFloat(data, "BATTERY_CAPACITY_SOC", "soc", "SOC", "soc_percent"); ok {
 		fields[envelope.FieldSOCPercent] = soc
@@ -166,6 +166,14 @@ func parseTimeMS(raw string, fallback int64) int64 {
 	if raw == "" {
 		return fallback
 	}
+	for _, layout := range []string{
+		"2006-01-02 15:04:05.000",
+		"2006-01-02 15:04:05",
+	} {
+		if parsed, err := time.ParseInLocation(layout, raw, time.FixedZone("Asia/Shanghai", 8*3600)); err == nil {
+			return parsed.UnixMilli()
+		}
+	}
 	if len(raw) == 14 {
 		if parsed, err := time.ParseInLocation("20060102150405", raw, time.FixedZone("Asia/Shanghai", 8*3600)); err == nil {
 			return parsed.UnixMilli()
@@ -187,3 +195,10 @@ func looksLikeVIN(value string) bool {
 	value = strings.TrimSpace(value)
 	return len(value) == 17
 }
+
+func normalizeTotalMileageKM(value float64) float64 {
+	if value > 1_000_000 {
+		return value / 1000
+	}
+	return value
+}
diff --git a/go/vehicle-gateway/internal/protocol/yutongmqtt/parser_test.go b/go/vehicle-gateway/internal/protocol/yutongmqtt/parser_test.go
index f348322c..91b5ef54 100644
--- a/go/vehicle-gateway/internal/protocol/yutongmqtt/parser_test.go
+++ b/go/vehicle-gateway/internal/protocol/yutongmqtt/parser_test.go
@@ -64,6 +64,22 @@ func TestParseMessageUsesDeviceAsVehicleKeyWhenNotVIN(t *testing.T) {
 	assertFloatField(t, env, envelope.FieldSpeedKMH, 12.3)
 }
 
+func TestParseMessageNormalizesProductionMileageMeters(t *testing.T) {
+	payload := []byte(`{
+	  "device":"LMRKH9AC3R1004101",
+	  "time":"2026-07-02 01:02:04.085",
+	  "data":{"TOTAL_MILEAGE":56905000,"METER_SPEED":19}
+	}`)
+	env, err := ParseMessage("yutong", "/ytforward/shln/1", payload, 1782940000000)
+	if err != nil {
+		t.Fatalf("ParseMessage() error = %v", err)
+	}
+	assertFloatField(t, env, envelope.FieldTotalMileageKM, 56905)
+	if env.EventTimeMS != 1782925324085 {
+		t.Fatalf("event time = %d, want 1782925324085", env.EventTimeMS)
+	}
+}
+
 func TestParseMessageRejectsMalformedJSON(t *testing.T) {
 	_, err := ParseMessage("endpoint-a", "/bad", []byte("{bad-json"), 1782745114999)
 	if !errors.Is(err, ErrInvalidJSON) {