feat: add Japanese Furigana support to lyrics display (#2161)

src/main/features/core/lyrics/furigana.ts

@@ -0,0 +1,37 @@
+import Kuroshiro from 'kuroshiro';
+import KuromojiAnalyzer from 'kuroshiro-analyzer-kuromoji';
+
+// doc: https://kuroshiro.org
+
+let kuroshiroInstance: any = null;
+let initPromise: null | Promise<void> = null;
+
+const getKuroshiro = async () => {
+    if (kuroshiroInstance) return kuroshiroInstance;
+    if (initPromise) {
+        await initPromise;
+        return kuroshiroInstance;
+    }
+
+    const KuroshiroClass = (Kuroshiro as any).default || Kuroshiro;
+    kuroshiroInstance = new KuroshiroClass();
+    initPromise = kuroshiroInstance.init(new KuromojiAnalyzer());
+    await initPromise;
+    return kuroshiroInstance;
+};
+
+export const convertFurigana = async (text: string): Promise<string> => {
+    const KuroshiroClass = (Kuroshiro as any).default || Kuroshiro;
+
+    // check if the text contains any Japanese kana (to distinguish Japanese from Chinese text, which shares Kanji)
+    // If no Japanese kana is detected, skip processing
+    if (!KuroshiroClass.Util.hasKana(text)) return text;
+
+    try {
+        const kuroshiro = await getKuroshiro();
+        return await kuroshiro.convert(text, { mode: 'furigana', to: 'hiragana' });
+    } catch (e) {
+        console.error('Furigana conversion error: ', e);
+        return text;
+    }
+};