fix: surface mileage child request failures

src/modules/mileage/StatisticsView.tsx

@@ -65,11 +65,11 @@ function shortTargetName(name: string): string {
   return `${count}台${desc}`;
 }
 
-function getRequestErrorMessage(error: unknown): string {
+function getRequestErrorMessage(error: unknown, fallback: string): string {
   if (error instanceof Error && error.message && error.message !== 'Failed to fetch') {
     return error.message;
   }
-  return '无法获取考核目标数据，请检查服务连接后重试。';
+  return fallback;
 }
 
 export default function StatisticsView() {
@@ -81,7 +81,12 @@ export default function StatisticsView() {
   const [targetsError, setTargetsError] = useState<string | null>(null);
   const [targetsRequestVersion, setTargetsRequestVersion] = useState(0);
   const [trendData, setTrendData] = useState<TrendPoint[]>([]);
+  const [trendLoading, setTrendLoading] = useState(false);
+  const [trendError, setTrendError] = useState<string | null>(null);
+  const [trendRequestVersion, setTrendRequestVersion] = useState(0);
   const [targetVehiclesMap, setTargetVehiclesMap] = useState<Record<number, TargetVehicle[]>>({});
+  const [targetVehicleLoadingMap, setTargetVehicleLoadingMap] = useState<Record<number, boolean>>({});
+  const [targetVehicleErrorMap, setTargetVehicleErrorMap] = useState<Record<number, string>>({});
   const [selectedTargetId, setSelectedTargetId] = useState<number | null>(drillContext.targetId || null);
   const [attributionDimension, setAttributionDimension] = useState<AttributionDimension>(() => (
     drillContext.level === 'breakdown' && drillContext.dimension === 'customer' ? 'customer' : 'department'
@@ -139,12 +144,28 @@ export default function StatisticsView() {
     setTargetsRequestVersion(version => version + 1);
   }, []);
 
+  const retryTrend = useCallback(() => {
+    setTrendRequestVersion(version => version + 1);
+  }, []);
+
   const loadCurrentTargetVehicles = useCallback((targetId: number) => {
     if (targetVehicleRequestsRef.current.has(targetId)) return;
     targetVehicleRequestsRef.current.add(targetId);
+    setTargetVehicleLoadingMap(prev => ({ ...prev, [targetId]: true }));
+    setTargetVehicleErrorMap(prev => {
+      const next = { ...prev };
+      delete next[targetId];
+      return next;
+    });
     fetchTargetVehicles(targetId).then(vehicles => {
       setTargetVehiclesMap(prev => ({ ...prev, [targetId]: vehicles }));
-    }).catch(() => {}).finally(() => {
+    }).catch(error => {
+      setTargetVehicleErrorMap(prev => ({
+        ...prev,
+        [targetId]: getRequestErrorMessage(error, '无法获取考核车辆数据，请稍后重试。'),
+      }));
+    }).finally(() => {
+      setTargetVehicleLoadingMap(prev => ({ ...prev, [targetId]: false }));
       targetVehicleRequestsRef.current.delete(targetId);
     });
   }, []);
@@ -267,7 +288,9 @@ export default function StatisticsView() {
         setAssessmentYearMap({});
       }
     }).catch(error => {
-      if (!cancelled) setTargetsError(getRequestErrorMessage(error));
+      if (!cancelled) {
+        setTargetsError(getRequestErrorMessage(error, '无法获取考核目标数据，请检查服务连接后重试。'));
+      }
     }).finally(() => {
       if (!cancelled) setTargetsLoading(false);
     });
@@ -278,13 +301,33 @@ export default function StatisticsView() {
 
   // Load trend when selectedTargetId changes
   useEffect(() => {
-    if (selectedTargetId === null) return;
+    if (selectedTargetId === null) {
+      setTrendData([]);
+      setTrendError(null);
+      setTrendLoading(false);
+      return;
+    }
+    let cancelled = false;
     setExpandedTargetId(selectedTargetId);
     if (!targetVehiclesMap[selectedTargetId]) {
       loadCurrentTargetVehicles(selectedTargetId);
     }
-    fetchTrend(selectedTargetId).then(setTrendData).catch(() => setTrendData([]));
-  }, [selectedTargetId]);
+    setTrendLoading(true);
+    setTrendError(null);
+    fetchTrend(selectedTargetId).then(data => {
+      if (!cancelled) setTrendData(data);
+    }).catch(error => {
+      if (!cancelled) {
+        setTrendData([]);
+        setTrendError(getRequestErrorMessage(error, '无法获取里程趋势，请稍后重试。'));
+      }
+    }).finally(() => {
+      if (!cancelled) setTrendLoading(false);
+    });
+    return () => {
+      cancelled = true;
+    };
+  }, [selectedTargetId, trendRequestVersion]);
 
   // Re-fetch target vehicles when viewAllDate changes
   useEffect(() => {
@@ -421,8 +464,8 @@ export default function StatisticsView() {
           </div>
           <div className="rounded-2xl border border-slate-100 bg-white p-3 shadow-sm">
             <div className="text-[10px] font-black uppercase tracking-wide text-slate-400">最新日变化</div>
-            <div className={`mt-1 text-lg font-black ${trendDelta >= 0 ? 'text-emerald-600' : 'text-rose-600'}`}>
-              {trendDelta >= 0 ? '+' : ''}{fmtKm(trendDelta)}
+            <div className={`mt-1 text-lg font-black ${trendLoading || trendError ? 'text-slate-500' : trendDelta >= 0 ? 'text-emerald-600' : 'text-rose-600'}`}>
+              {trendLoading ? '加载中' : trendError ? '暂不可用' : `${trendDelta >= 0 ? '+' : ''}${fmtKm(trendDelta)}`}
             </div>
             <div className="mt-1 text-[10px] font-bold text-slate-400">达标率 {fmtPercent(selectedQualifiedRate)}</div>
           </div>
@@ -448,7 +491,9 @@ export default function StatisticsView() {
           vehicles={selectedTargetVehicles}
           dimension={attributionDimension}
           selectedValue={selectedBreakdownValue}
-          loading={!targetVehiclesMap[selectedTarget.id]}
+          loading={targetVehicleLoadingMap[selectedTarget.id]
+            || (!targetVehiclesMap[selectedTarget.id] && !targetVehicleErrorMap[selectedTarget.id])}
+          error={targetVehicleErrorMap[selectedTarget.id]}
           targetMileagePerVehicle={selectedTarget.annualMileagePerVehicle * (selectedAssessmentYear || 1)}
           expectedShortfallMileage={selectedAssessment?.remaining}
           assessmentLabel={selectedAssessment?.label}
@@ -457,6 +502,7 @@ export default function StatisticsView() {
             if (drillContext.level === 'breakdown') closeVehiclePanel();
           }}
           onSelect={openAttributionGroup}
+          onRetry={() => loadCurrentTargetVehicles(selectedTarget.id)}
         />
       )}
 
@@ -521,6 +567,13 @@ export default function StatisticsView() {
               </div>
             </div>
             <div className="h-[280px] w-full min-w-0">
+              {trendLoading ? (
+                <LoadingState label="正在加载里程趋势" variant="inline" />
+              ) : trendError ? (
+                <ErrorState message={trendError} onRetry={retryTrend} variant="inline" />
+              ) : trendData.length === 0 ? (
+                <EmptyState title="暂无趋势数据" description="当前考核目标在最近 7 天没有可用里程" variant="inline" />
+              ) : (
                 <ResponsiveContainer width="100%" height={280} minWidth={0}>
                 {chartType === 'bar' ? (
                   <BarChart data={trendData} margin={{ top: 20, right: 10, left: 0, bottom: 0 }}>
@@ -563,6 +616,7 @@ export default function StatisticsView() {
                   </AreaChart>
                 )}
                 </ResponsiveContainer>
+              )}
             </div>
           </div>
         </div>