feat: Feature flag support

packages/common/src/utils.ts

@@ -1321,3 +1321,47 @@ export const isMobileOrTablet = (): boolean => {
   }
   return false;
 };
+
+type FEATURE_FLAGS = {
+  COMPLEX_BINDINGS: boolean;
+};
+
+const FEATURE_FLAGS_STORAGE_KEY = "feature-flags";
+const DEFAULT_FEATURE_FLAGS: FEATURE_FLAGS = {
+  COMPLEX_BINDINGS: false,
+};
+let featureFlags: FEATURE_FLAGS | null = null;
+
+export const getFeatureFlag = <F extends keyof FEATURE_FLAGS>(
+  flag: F,
+): FEATURE_FLAGS[F] => {
+  if (!featureFlags) {
+    try {
+      const serializedFlags = localStorage.getItem(FEATURE_FLAGS_STORAGE_KEY);
+      if (serializedFlags) {
+        const flags = JSON.parse(serializedFlags);
+        featureFlags = flags ?? DEFAULT_FEATURE_FLAGS;
+      }
+    } catch {}
+  }
+
+  return (featureFlags || DEFAULT_FEATURE_FLAGS)[flag];
+};
+
+export const setFeatureFlag = <F extends keyof FEATURE_FLAGS>(
+  flag: F,
+  value: FEATURE_FLAGS[F],
+) => {
+  try {
+    featureFlags = {
+      ...(featureFlags || DEFAULT_FEATURE_FLAGS),
+      [flag]: value,
+    };
+    localStorage.setItem(
+      FEATURE_FLAGS_STORAGE_KEY,
+      JSON.stringify(featureFlags),
+    );
+  } catch (e) {
+    console.error("unable to set feature flag", e);
+  }
+};