feat(hooks): add useProblemEditor hook for managing problem-specific editor language

src/hooks/useProblemEditor.ts

@@ -0,0 +1,53 @@
+import { EditorLanguage } from "@prisma/client";
+import { useEffect, useState, useCallback } from "react";
+import { useProblemEditorStore } from "@/store/useProblemEditorStore";
+
+/**
+ * Generates a unique localStorage key for storing the editor language of a problem.
+ */
+const getProblemLangStorageKey = (problemId: string) => `${problemId}_lang`;
+
+/**
+ * Retrieves the stored editor language for a specific problem.
+ * If no value is found, it falls back to the global editor language.
+ */
+const getStoredProblemLang = (problemId: string, globalEditorLanguage: EditorLanguage): EditorLanguage => {
+  return (localStorage.getItem(getProblemLangStorageKey(problemId)) as EditorLanguage) ?? globalEditorLanguage;
+};
+
+/**
+ * Hook for managing the editor language of a specific problem.
+ */
+export const useProblemEditor = (problemId: string) => {
+  const { globalEditorLanguage, setGlobalEditorLanguage } = useProblemEditorStore();
+
+  // Local state to track the current editor language for the problem
+  const [currentLang, setCurrentLang] = useState<EditorLanguage>(() => 
+    getStoredProblemLang(problemId, globalEditorLanguage)
+  );
+
+  // Update local state when the problemId or global editor language changes
+  useEffect(() => {
+    setCurrentLang(getStoredProblemLang(problemId, globalEditorLanguage));
+  }, [problemId, globalEditorLanguage]);
+
+  /**
+   * Changes the editor language for the current problem.
+   * Updates both global state and local storage.
+   */
+  const changeProblemLang = useCallback(
+    (language: EditorLanguage) => {
+      // Update global editor language state
+      setGlobalEditorLanguage(language);
+
+      // Persist the selected language in localStorage
+      localStorage.setItem(getProblemLangStorageKey(problemId), language);
+
+      // Update local state
+      setCurrentLang(language);
+    },
+    [setGlobalEditorLanguage]
+  );
+
+  return { currentLang, changeProblemLang };
+};