대시보드 실시간 기능 추가

features/trade/hooks/useOrderBook.ts

@@ -1,4 +1,4 @@
-import { useEffect, useRef, useState } from "react";
+import { useEffect, useMemo, useRef, useState } from "react";
 import type { KisRuntimeCredentials } from "@/features/settings/store/use-kis-runtime-store";
 import type { DashboardStockOrderBookResponse } from "@/features/trade/types/trade.types";
 import { fetchStockOrderBook } from "@/features/trade/apis/kis-stock.api";
@@ -29,9 +29,22 @@ export function useOrderBook(
 
   const [initialData, setInitialData] =
     useState<DashboardStockOrderBookResponse | null>(null);
+  const [lastRealtimeWithLevels, setLastRealtimeWithLevels] =
+    useState<DashboardStockOrderBookResponse | null>(null);
   const [isLoading, setIsLoading] = useState(false);
   const [error, setError] = useState<string | null>(null);
 
+  useEffect(() => {
+    if (!isRequestEnabled) {
+      setLastRealtimeWithLevels(null);
+      return;
+    }
+
+    if (externalRealtimeOrderBook && hasOrderBookLevelData(externalRealtimeOrderBook)) {
+      setLastRealtimeWithLevels(externalRealtimeOrderBook);
+    }
+  }, [externalRealtimeOrderBook, isRequestEnabled]);
+
   useEffect(() => {
     if (!isRequestEnabled || !symbol || !credentials) {
       return;
@@ -75,10 +88,67 @@ export function useOrderBook(
     };
   }, [isRequestEnabled, symbol, credentials]);
 
-  // 외부 실시간 호가 → 초기 데이터 → null 순 우선
-  const orderBook = isRequestEnabled
-    ? (externalRealtimeOrderBook ?? initialData)
-    : null;
+  // 외부 실시간 호가가 비어 있으면(가격/잔량 레벨 0) 마지막 정상 실시간 또는 REST 초기값을 유지합니다.
+  const orderBook = useMemo(() => {
+    if (!isRequestEnabled) return null;
+
+    if (externalRealtimeOrderBook) {
+      if (hasOrderBookLevelData(externalRealtimeOrderBook)) {
+        return externalRealtimeOrderBook;
+      }
+
+      if (lastRealtimeWithLevels) {
+        return {
+          ...lastRealtimeWithLevels,
+          totalAskSize: externalRealtimeOrderBook.totalAskSize,
+          totalBidSize: externalRealtimeOrderBook.totalBidSize,
+          anticipatedPrice: externalRealtimeOrderBook.anticipatedPrice,
+          anticipatedVolume: externalRealtimeOrderBook.anticipatedVolume,
+          anticipatedTotalVolume: externalRealtimeOrderBook.anticipatedTotalVolume,
+          anticipatedChange: externalRealtimeOrderBook.anticipatedChange,
+          anticipatedChangeSign: externalRealtimeOrderBook.anticipatedChangeSign,
+          anticipatedChangeRate: externalRealtimeOrderBook.anticipatedChangeRate,
+          accumulatedVolume: externalRealtimeOrderBook.accumulatedVolume,
+          totalAskSizeDelta: externalRealtimeOrderBook.totalAskSizeDelta,
+          totalBidSizeDelta: externalRealtimeOrderBook.totalBidSizeDelta,
+          businessHour:
+            externalRealtimeOrderBook.businessHour ?? lastRealtimeWithLevels.businessHour,
+          hourClassCode:
+            externalRealtimeOrderBook.hourClassCode ?? lastRealtimeWithLevels.hourClassCode,
+          fetchedAt: externalRealtimeOrderBook.fetchedAt,
+          tradingEnv: externalRealtimeOrderBook.tradingEnv,
+          source: externalRealtimeOrderBook.source,
+        };
+      }
+
+      if (initialData && hasOrderBookLevelData(initialData)) {
+        return {
+          ...initialData,
+          totalAskSize: externalRealtimeOrderBook.totalAskSize,
+          totalBidSize: externalRealtimeOrderBook.totalBidSize,
+          anticipatedPrice: externalRealtimeOrderBook.anticipatedPrice,
+          anticipatedVolume: externalRealtimeOrderBook.anticipatedVolume,
+          anticipatedTotalVolume: externalRealtimeOrderBook.anticipatedTotalVolume,
+          anticipatedChange: externalRealtimeOrderBook.anticipatedChange,
+          anticipatedChangeSign: externalRealtimeOrderBook.anticipatedChangeSign,
+          anticipatedChangeRate: externalRealtimeOrderBook.anticipatedChangeRate,
+          accumulatedVolume: externalRealtimeOrderBook.accumulatedVolume,
+          totalAskSizeDelta: externalRealtimeOrderBook.totalAskSizeDelta,
+          totalBidSizeDelta: externalRealtimeOrderBook.totalBidSizeDelta,
+          businessHour: externalRealtimeOrderBook.businessHour ?? initialData.businessHour,
+          hourClassCode: externalRealtimeOrderBook.hourClassCode ?? initialData.hourClassCode,
+          fetchedAt: externalRealtimeOrderBook.fetchedAt,
+          tradingEnv: externalRealtimeOrderBook.tradingEnv,
+          source: externalRealtimeOrderBook.source,
+        };
+      }
+
+      return externalRealtimeOrderBook;
+    }
+
+    return initialData;
+  }, [externalRealtimeOrderBook, initialData, isRequestEnabled, lastRealtimeWithLevels]);
+
   const mergedError = isRequestEnabled ? error : null;
   const mergedLoading = isRequestEnabled ? isLoading && !orderBook : false;
 
@@ -89,3 +159,13 @@ export function useOrderBook(
     isWsConnected: !!externalRealtimeOrderBook,
   };
 }
+
+function hasOrderBookLevelData(orderBook: DashboardStockOrderBookResponse) {
+  return orderBook.levels.some(
+    (level) =>
+      level.askPrice > 0 ||
+      level.bidPrice > 0 ||
+      level.askSize > 0 ||
+      level.bidSize > 0,
+  );
+}