From 24e1d33642861b03ece91cd5276be35eca94183c Mon Sep 17 00:00:00 2001
From: MengYX <admin@mengyx.cn>
Date: Tue, 10 Mar 2020 09:31:48 +0800
Subject: [PATCH] Fix errors when parsing ncm files without metadata

---
 src/App.vue           |  2 +-
 src/decrypt/common.js |  2 +-
 src/decrypt/ncm.js    | 29 ++++++++++++++---------------
 3 files changed, 16 insertions(+), 17 deletions(-)

diff --git a/src/App.vue b/src/App.vue
index 1cb5ffb..4fa9b3b 100644
--- a/src/App.vue
+++ b/src/App.vue
@@ -140,8 +140,8 @@
                 });
                 if (process.env.NODE_ENV === 'production') {
                     window._paq.push(["trackEvent", "Error", errInfo, filename]);
-                    console.error(errInfo, filename);
                 }
+                console.error(errInfo, filename);
             },
             changePlaying(url) {
                 this.playing_url = url;
diff --git a/src/decrypt/common.js b/src/decrypt/common.js
index cef10f9..04d7037 100644
--- a/src/decrypt/common.js
+++ b/src/decrypt/common.js
@@ -9,7 +9,7 @@ export async function CommonDecrypt(file) {
     let rt_data;
     switch (raw_ext) {
         case "ncm":// Netease Mp3/Flac
-            rt_data = await NcmDecrypt.Decrypt(file.raw);
+            rt_data = await NcmDecrypt.Decrypt(file.raw, raw_filename, raw_ext);
             break;
         case "mp3":// Raw Mp3
         case "flac"://Raw Flac
diff --git a/src/decrypt/ncm.js b/src/decrypt/ncm.js
index 10c2a16..245d98b 100644
--- a/src/decrypt/ncm.js
+++ b/src/decrypt/ncm.js
@@ -2,10 +2,9 @@ const CryptoJS = require("crypto-js");
 const ID3Writer = require("browser-id3-writer");
 const CORE_KEY = CryptoJS.enc.Hex.parse("687a4852416d736f356b496e62617857");
 const META_KEY = CryptoJS.enc.Hex.parse("2331346C6A6B5F215C5D2630553C2728");
-import {AudioMimeType, DetectAudioExt, GetArrayBuffer} from "./util"
-
-export async function Decrypt(file) {
+import {AudioMimeType, DetectAudioExt, GetArrayBuffer, GetFileInfo} from "./util"
 
+export async function Decrypt(file, raw_filename, raw_ext) {
     const fileBuffer = await GetArrayBuffer(file);
     const dataView = new DataView(fileBuffer);
 
@@ -13,32 +12,34 @@ export async function Decrypt(file) {
         dataView.getUint32(4, true) !== 0x4d414446)
         return {status: false, message: "此ncm文件已损坏"};
 
-
     const keyDataObj = getKeyData(dataView, fileBuffer, 10);
     const keyBox = getKeyBox(keyDataObj.data);
 
     const musicMetaObj = getMetaData(dataView, fileBuffer, keyDataObj.offset);
     const musicMeta = musicMetaObj.data;
-
     let audioOffset = musicMetaObj.offset + dataView.getUint32(musicMetaObj.offset + 5, true) + 13;
     let audioData = new Uint8Array(fileBuffer, audioOffset);
 
     for (let cur = 0; cur < audioData.length; ++cur) audioData[cur] ^= keyBox[cur & 0xff];
 
-    if (musicMeta.format === undefined) musicMeta.format = DetectAudioExt(audioData, "mp3");
 
-    const mime = AudioMimeType[musicMeta.format];
+    if (musicMeta.album === undefined) musicMeta.album = "";
 
     const artists = [];
-    musicMeta.artist.forEach(arr => artists.push(arr[0]));
-    if (musicMeta.format === "mp3")
-        audioData = await writeID3(audioData, artists, musicMeta.musicName, musicMeta.album, musicMeta.albumPic);
+    if (!!musicMeta.artist) musicMeta.artist.forEach(arr => artists.push(arr[0]));
+    const info = GetFileInfo(artists.join(" & "), musicMeta.musicName, raw_filename);
+    if (artists.length === 0) artists.push(info.artist);
 
+    if (musicMeta.format === undefined) musicMeta.format = DetectAudioExt(audioData, "mp3");
+    if (musicMeta.format === "mp3")
+        audioData = await writeID3(audioData, artists, info.title, musicMeta.album, musicMeta.albumPic);
+
+    const mime = AudioMimeType[musicMeta.format];
     const musicData = new Blob([audioData], {type: mime});
     return {
         status: true,
-        title: musicMeta.musicName,
-        artist: artists.join(" & "),
+        title: info.title,
+        artist: info.artist,
         ext: musicMeta.format,
         album: musicMeta.album,
         picture: musicMeta.albumPic,
@@ -129,9 +130,7 @@ function getKeyBox(keyData) {
 function getMetaData(dataView, fileBuffer, offset) {
     const metaDataLen = dataView.getUint32(offset, true);
     offset += 4;
-    if (metaDataLen === 0) {
-        return {};
-    }
+    if (metaDataLen === 0) return {data: {}, offset: offset};
 
     const cipherText = new Uint8Array(fileBuffer, offset, metaDataLen).map(
         data => data ^ 0x63