From 3b43957cee0eef05ccf9f04c1147577ed2db77a4 Mon Sep 17 00:00:00 2001
From: Xmader <xmader@outlook.com>
Date: Tue, 24 Nov 2020 04:36:01 -0500
Subject: [PATCH] feat: load webmscore in nodejs

---
 src/mscore.ts | 49 +++++++++++++++++++++++++++++++++----------------
 1 file changed, 33 insertions(+), 16 deletions(-)

diff --git a/src/mscore.ts b/src/mscore.ts
index 9e0be1a..e9efcfa 100644
--- a/src/mscore.ts
+++ b/src/mscore.ts
@@ -1,6 +1,8 @@
+/* eslint-disable @typescript-eslint/no-var-requires */
 
 import { fetchMscz } from './mscz'
 import { fetchData } from './utils'
+import { ScoreInfo } from './scoreinfo'
 
 const WEBMSCORE_URL = 'https://cdn.jsdelivr.net/npm/webmscore@0.10/webmscore.js'
 
@@ -12,25 +14,41 @@ const SF3_URL = 'https://cdn.jsdelivr.net/npm/@librescore/sf3/FluidR3Mono_GM.sf3
 const SOUND_FONT_LOADED = Symbol('SoundFont loaded')
 
 export type WebMscore = import('webmscore').default
+export type WebMscoreConstr = typeof import('webmscore').default
 
-const initMscore = async (w: Window) => {
-  if (!w['WebMscore']) {
-    // init webmscore (https://github.com/LibreScore/webmscore)
-    const script = w.document.createElement('script')
-    script.src = WEBMSCORE_URL
-    w.document.body.append(script)
-    await new Promise(resolve => { script.onload = resolve })
+const initMscore = async (w?: Window): Promise<WebMscoreConstr> => {
+  if (w !== undefined) { // attached to a page
+    if (!w['WebMscore']) {
+      // init webmscore (https://github.com/LibreScore/webmscore)
+      const script = w.document.createElement('script')
+      script.src = WEBMSCORE_URL
+      w.document.body.append(script)
+      await new Promise(resolve => { script.onload = resolve })
+    }
+    return w['WebMscore'] as WebMscoreConstr
+  } else { // nodejs
+    return require('webmscore').default as WebMscoreConstr
   }
 }
 
 let fonts: Promise<Uint8Array[]> | undefined
-const initFonts = () => {
+const initFonts = (nodeJs: boolean) => {
   // load CJK fonts
   // CJK (East Asian) characters will be rendered as "tofu" if there is no font
   if (!fonts) {
-    fonts = Promise.all(
-      FONT_URLS.map(url => fetchData(url)),
-    )
+    if (nodeJs) {
+      // module.exports.CN = ..., module.exports.KR = ...
+      const FONTS = Object.values(require('@librescore/fonts'))
+
+      const fs = require('fs')
+      fonts = Promise.all(
+        FONTS.map((path: string) => fs.promises.readFile(path) as Promise<Buffer>),
+      )
+    } else {
+      fonts = Promise.all(
+        FONT_URLS.map(url => fetchData(url)),
+      )
+    }
   }
 }
 
@@ -46,14 +64,13 @@ export const loadSoundFont = (score: WebMscore): Promise<void> => {
   return score[SOUND_FONT_LOADED] as Promise<void>
 }
 
-export const loadMscore = async (w: Window): Promise<WebMscore> => {
-  initFonts()
-  await initMscore(w)
+export const loadMscore = async (scoreinfo: ScoreInfo, w?: Window): Promise<WebMscore> => {
+  initFonts(w === undefined)
+  const WebMscore = await initMscore(w)
 
-  const WebMscore: typeof import('webmscore').default = w['WebMscore']
   // parse mscz data
   const data = new Uint8Array(
-    new Uint8Array(await fetchMscz()), // copy its ArrayBuffer
+    new Uint8Array(await fetchMscz(scoreinfo)), // copy its ArrayBuffer
   )
   const score = await WebMscore.load('mscz', data, await fonts)
   await score.generateExcerpts()