404에러 패치

frontend/src/utils/strategyMissingCache.ts

@@ -0,0 +1,63 @@
+/**
+ * 서버에 없는 전략 ID — 세션 간 404 반복 방지 (sessionStorage)
+ */
+const STORAGE_KEY = 'gc_strategy_missing_ids_v1';
+const MAX_STORED = 64;
+
+const strategyMissingIds = new Set<number>();
+
+function persistStrategyMissingCache(): void {
+  try {
+    const arr = [...strategyMissingIds].filter(id => id > 0).slice(-MAX_STORED);
+    if (arr.length === 0) sessionStorage.removeItem(STORAGE_KEY);
+    else sessionStorage.setItem(STORAGE_KEY, JSON.stringify(arr));
+  } catch {
+    /* private mode · 용량 */
+  }
+}
+
+/** 앱 기동 시 이전 탭에서 기록한 missing ID 복원 */
+export function hydrateStrategyMissingCache(): void {
+  try {
+    const raw = sessionStorage.getItem(STORAGE_KEY);
+    if (!raw) return;
+    const parsed = JSON.parse(raw) as unknown;
+    if (!Array.isArray(parsed)) return;
+    for (const n of parsed) {
+      const id = Number(n);
+      if (id > 0) strategyMissingIds.add(id);
+    }
+  } catch {
+    try { sessionStorage.removeItem(STORAGE_KEY); } catch { /* ok */ }
+  }
+}
+
+export function isStrategyMissingOnServer(strategyId: number): boolean {
+  return strategyId > 0 && strategyMissingIds.has(strategyId);
+}
+
+export function markStrategyMissingOnServer(strategyId: number): void {
+  if (strategyId <= 0) return;
+  strategyMissingIds.add(strategyId);
+  persistStrategyMissingCache();
+}
+
+/** 전략 목록에 다시 나타난 ID 는 missing 에서 제거 */
+export function reconcileStrategyMissingWithValidIds(validIds: Iterable<number>): void {
+  const valid = new Set(validIds);
+  let changed = false;
+  for (const id of strategyMissingIds) {
+    if (valid.has(id)) {
+      strategyMissingIds.delete(id);
+      changed = true;
+    }
+  }
+  if (changed) persistStrategyMissingCache();
+}
+
+export function markStrategyMissingFromPath(pathOnly: string): void {
+  const m = pathOnly.match(/^\/strategies\/(\d+)(?:\/|$)/);
+  if (m) markStrategyMissingOnServer(Number(m[1]));
+}
+
+hydrateStrategyMissingCache();