실시간 웹소켓 리팩토링

features/trade/components/orderbook/OrderBook.tsx

@@ -14,7 +14,6 @@ import { AnimatedQuantity } from "./AnimatedQuantity";
 interface OrderBookProps {
   symbol?: string;
   referencePrice?: number;
-  currentPrice?: number;
   latestTick: DashboardRealtimeTradeTick | null;
   recentTicks: DashboardRealtimeTradeTick[];
   orderBook: DashboardStockOrderBookResponse | null;
@@ -24,7 +23,7 @@ interface OrderBookProps {
 interface BookRow {
   price: number;
   size: number;
-  changePercent: number | null;
+  changeValue: number | null;
   isHighlighted: boolean;
 }
 
@@ -79,6 +78,51 @@ function pctChange(price: number, base: number) {
   return base > 0 ? ((price - base) / base) * 100 : 0;
 }
 
+/**
+ * @description 기준가 대비 증감값/증감률을 함께 계산합니다.
+ * @see features/trade/components/orderbook/OrderBook.tsx buildBookRows
+ */
+function resolvePriceChange(price: number, basePrice: number) {
+  if (price <= 0 || basePrice <= 0) {
+    return { changeValue: null } as const;
+  }
+
+  const changeValue = price - basePrice;
+
+  return { changeValue } as const;
+}
+
+/**
+ * @description 증감 숫자를 부호 포함 문자열로 포맷합니다.
+ * @see features/trade/components/orderbook/OrderBook.tsx BookSideRows
+ */
+function fmtSignedChange(v: number) {
+  if (!Number.isFinite(v)) return "-";
+  if (v > 0) return `+${fmt(v)}`;
+  if (v < 0) return `-${fmt(Math.abs(v))}`;
+  return "0";
+}
+
+/**
+ * @description 증감값에 따라 색상 톤 클래스를 반환합니다.
+ * @see features/trade/components/orderbook/OrderBook.tsx BookSideRows
+ */
+function getChangeToneClass(
+  changeValue: number | null,
+  neutralClass = "text-muted-foreground",
+) {
+  if (changeValue === null) {
+    return neutralClass;
+  }
+  if (changeValue > 0) {
+    return "text-red-500";
+  }
+  if (changeValue < 0) {
+    return "text-blue-600 dark:text-blue-400";
+  }
+  return neutralClass;
+}
+
 /** 체결 시각 포맷 */
 function fmtTime(hms: string) {
   if (!hms || hms.length !== 6) return "--:--:--";
@@ -131,6 +175,65 @@ function resolveTickExecutionSide(
   return "neutral" as const;
 }
 
+/**
+ * @description 호가 레벨을 화면 렌더링용 행 모델로 변환합니다.
+ * UI 흐름: OrderBook(levels/basePrice/latestPrice) -> buildBookRows -> BookSideRows -> 가격/증감 반영
+ * @see features/trade/components/orderbook/OrderBook.tsx OrderBook askRows/bidRows 계산
+ */
+function buildBookRows({
+  levels,
+  side,
+  basePrice,
+  latestPrice,
+}: {
+  levels: DashboardStockOrderBookResponse["levels"];
+  side: "ask" | "bid";
+  basePrice: number;
+  latestPrice: number;
+}) {
+  const normalizedLevels = side === "ask" ? [...levels].reverse() : levels;
+
+  return normalizedLevels.map((level) => {
+    const price = side === "ask" ? level.askPrice : level.bidPrice;
+    const size = side === "ask" ? level.askSize : level.bidSize;
+    const { changeValue } = resolvePriceChange(price, basePrice);
+
+    return {
+      price,
+      size: Math.max(size, 0),
+      changeValue,
+      isHighlighted: latestPrice > 0 && price === latestPrice,
+    } satisfies BookRow;
+  });
+}
+
+/**
+ * @description 호가/체결 증감 표시용 기준가(전일종가)를 결정합니다.
+ * @summary UI 흐름: OrderBook props -> resolveReferencePrice -> 호가행/체결가 증감 계산 반영
+ * @see features/trade/components/orderbook/OrderBook.tsx basePrice 계산
+ */
+function resolveReferencePrice({
+  referencePrice,
+  latestTick,
+}: {
+  referencePrice?: number;
+  latestTick: DashboardRealtimeTradeTick | null;
+}) {
+  if ((referencePrice ?? 0) > 0) {
+    return referencePrice!;
+  }
+
+  // referencePrice 미전달 케이스에서도 틱 데이터(price-change)로 전일종가를 역산합니다.
+  if (latestTick?.price && Number.isFinite(latestTick.change)) {
+    const derivedPrevClose = latestTick.price - latestTick.change;
+    if (derivedPrevClose > 0) {
+      return derivedPrevClose;
+    }
+  }
+
+  return 0;
+}
+
 // ─── 메인 컴포넌트 ──────────────────────────────────────
 
 /**
@@ -139,7 +242,6 @@ function resolveTickExecutionSide(
 export function OrderBook({
   symbol,
   referencePrice,
-  currentPrice,
   latestTick,
   recentTicks,
   orderBook,
@@ -162,42 +264,29 @@ export function OrderBook({
     latestTick?.price && latestTick.price > 0 ? latestTick.price : 0;
 
   // 등락률 기준가
-  const basePrice =
-    (referencePrice ?? 0) > 0
-      ? referencePrice!
-      : (currentPrice ?? 0) > 0
-        ? currentPrice!
-        : latestPrice > 0
-          ? latestPrice
-          : 0;
+  const basePrice = resolveReferencePrice({ referencePrice, latestTick });
 
   // 매도호가 (역순: 10호가 → 1호가)
   const askRows: BookRow[] = useMemo(
     () =>
-      [...levels].reverse().map((l) => ({
-        price: l.askPrice,
-        size: Math.max(l.askSize, 0),
-        changePercent:
-          l.askPrice > 0 && basePrice > 0
-            ? pctChange(l.askPrice, basePrice)
-            : null,
-        isHighlighted: latestPrice > 0 && l.askPrice === latestPrice,
-      })),
+      buildBookRows({
+        levels,
+        side: "ask",
+        basePrice,
+        latestPrice,
+      }),
     [levels, basePrice, latestPrice],
   );
 
   // 매수호가 (1호가 → 10호가)
   const bidRows: BookRow[] = useMemo(
     () =>
-      levels.map((l) => ({
-        price: l.bidPrice,
-        size: Math.max(l.bidSize, 0),
-        changePercent:
-          l.bidPrice > 0 && basePrice > 0
-            ? pctChange(l.bidPrice, basePrice)
-            : null,
-        isHighlighted: latestPrice > 0 && l.bidPrice === latestPrice,
-      })),
+      buildBookRows({
+        levels,
+        side: "bid",
+        basePrice,
+        latestPrice,
+      }),
     [levels, basePrice, latestPrice],
   );
 
@@ -439,15 +528,11 @@ function BookSideRows({
               </span>
               <span
                 className={cn(
-                  "text-[10px]",
-                  row.changePercent !== null
-                    ? row.changePercent >= 0
-                      ? "text-red-500"
-                      : "text-blue-600 dark:text-blue-400"
-                    : "text-muted-foreground",
+                  "w-[58px] shrink-0 text-right text-[10px] tabular-nums",
+                  getChangeToneClass(row.changeValue),
                 )}
               >
-                {row.changePercent === null ? "-" : fmtPct(row.changePercent)}
+                {row.changeValue === null ? "-" : fmtSignedChange(row.changeValue)}
               </span>
             </div>
 
@@ -635,7 +720,12 @@ function TradeTape({ ticks }: { ticks: DashboardRealtimeTradeTick[] }) {
                 <div className="flex items-center tabular-nums">
                   {fmtTime(t.tickTime)}
                 </div>
-                <div className="flex items-center justify-end tabular-nums text-red-600">
+                <div
+                  className={cn(
+                    "flex items-center justify-end tabular-nums",
+                    getChangeToneClass(t.change, "text-foreground dark:text-brand-50"),
+                  )}
+                >
                   {fmt(t.price)}
                 </div>
                 <div