Settings API for loader, preview branch select

frontend/src/utils/hooks/useSetting.ts

@@ -0,0 +1,39 @@
+import { useEffect, useState } from 'react';
+
+interface GetSettingArgs<T> {
+  key: string;
+  default: T;
+}
+
+interface SetSettingArgs<T> {
+  key: string;
+  value: T;
+}
+
+export function useSetting<T>(key: string, def: T): [value: T | null, setValue: (value: T) => void] {
+  const [value, setValue] = useState(def);
+  const [ready, setReady] = useState<boolean>(false);
+
+  useEffect(() => {
+    (async () => {
+      const res = (await window.DeckyPluginLoader.callServerMethod('get_setting', {
+        key,
+        default: def,
+      } as GetSettingArgs<T>)) as { result: T };
+      setReady(true);
+      setValue(res.result);
+    })();
+  }, []);
+
+  useEffect(() => {
+    if (ready)
+      (async () => {
+        await window.DeckyPluginLoader.callServerMethod('set_setting', {
+          key,
+          value,
+        } as SetSettingArgs<T>);
+      })();
+  }, [value]);
+
+  return [value, setValue];
+}