From dd965688a9599f890e84aa03ba078d6d95fca8cb Mon Sep 17 00:00:00 2001
From: MengYX <admin@mengyx.cn>
Date: Sun, 26 Apr 2020 14:32:32 +0800
Subject: [PATCH] Fix Qmc Mask Query

---
 package.json       |  1 +
 src/decrypt/qmc.js | 15 +++++++++------
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/package.json b/package.json
index 4fe5021..f38a486 100644
--- a/package.json
+++ b/package.json
@@ -15,6 +15,7 @@
     "fix-compatibility": "node ./src/fix-compatibility.js"
   },
   "dependencies": {
+    "base64-js": "^1.3.1",
     "browser-id3-writer": "^4.4.0",
     "core-js": "^3.6.4",
     "crypto-js": "^4.0.0",
diff --git a/src/decrypt/qmc.js b/src/decrypt/qmc.js
index 9490d55..c68d711 100644
--- a/src/decrypt/qmc.js
+++ b/src/decrypt/qmc.js
@@ -1,7 +1,8 @@
 import {AudioMimeType, DetectAudioExt, GetArrayBuffer, GetFileInfo, GetMetaCoverURL, RequestJsonp} from "./util";
 import {QmcMaskCreate58, QmcMaskDetectMflac, QmcMaskDetectMgg, QmcMaskGetDefault} from "./qmcMask";
 
-import {decode} from "iconv-lite"
+
+import {fromByteArray as Base64Encode, toByteArray as Base64Decode} from 'base64-js'
 
 const musicMetadata = require("music-metadata-browser");
 
@@ -25,9 +26,11 @@ export async function Decrypt(file, raw_filename, raw_ext) {
     const fileData = new Uint8Array(await GetArrayBuffer(file));
     let audioData, seed, keyData;
     if (handler.detect) {
-        audioData = fileData.slice(0, -0x170);
+        const keyLen = new DataView(fileData.slice(fileData.length - 4).buffer).getUint32(0, true)
+        const keyPos = fileData.length - 4 - keyLen;
+        audioData = fileData.slice(0, keyPos);
         seed = handler.handler(audioData);
-        keyData = fileData.slice(-0x170);
+        keyData = fileData.slice(keyPos, keyPos + keyLen);
         if (seed === undefined) seed = await queryKeyInfo(keyData, raw_filename, raw_ext);
         if (seed === undefined) return {status: false, message: raw_ext + "格式仅提供实验性支持"};
     } else {
@@ -76,7 +79,7 @@ function reportKeyUsage(keyData, maskData, artist, title, album, filename, forma
         method: "POST",
         headers: {"Content-Type": "application/json"},
         body: JSON.stringify({
-            Mask: Array.from(maskData), Key: Array.from(keyData),
+            Mask: Base64Encode(new Uint8Array(maskData)), Key: Base64Encode(keyData),
             Artist: artist, Title: title, Album: album, Filename: filename, Format: format
         }),
     }).then().catch()
@@ -87,10 +90,10 @@ async function queryKeyInfo(keyData, filename, format) {
         const resp = await fetch("https://stats.ixarea.com/collect/qmcmask/query", {
             method: "POST",
             headers: {"Content-Type": "application/json"},
-            body: JSON.stringify({Format: format, Key: Array.from(keyData), Filename: filename}),
+            body: JSON.stringify({Format: format, Key: Base64Encode(keyData), Filename: filename, Type: 44}),
         });
         let data = await resp.json();
-        return QmcMaskCreate58(data.Matrix58, data.Super58A, data.Super58B);
+        return QmcMaskCreate58(Base64Decode(data.Matrix44));
     } catch (e) {
         console.log(e);
     }