From 2dff0c1f376f6cc1afde4f30a80d449d5f5d54ea Mon Sep 17 00:00:00 2001
From: Jixun Wu <jixun.moe@gmail.com>
Date: Mon, 21 Nov 2022 18:14:44 +0000
Subject: [PATCH] test: added test cases for qmc cache.

---
 src/decrypt/__test__/QmcCache.test.ts         |  20 ++++
 .../__test__/fixture/qmc_cache_expected.bin   | Bin 0 -> 256 bytes
 src/decrypt/qmccache.ts                       | 104 +++++++++---------
 3 files changed, 74 insertions(+), 50 deletions(-)
 create mode 100644 src/decrypt/__test__/QmcCache.test.ts
 create mode 100644 src/decrypt/__test__/fixture/qmc_cache_expected.bin

diff --git a/src/decrypt/__test__/QmcCache.test.ts b/src/decrypt/__test__/QmcCache.test.ts
new file mode 100644
index 0000000..2cbc45d
--- /dev/null
+++ b/src/decrypt/__test__/QmcCache.test.ts
@@ -0,0 +1,20 @@
+import { DecryptBuffer as DecryptQmcCacheBuffer } from '../qmccache';
+import fs from 'fs';
+
+const expectedBuffer = fs.readFileSync(__dirname + '/fixture/qmc_cache_expected.bin');
+
+const createInputBuffer = () => {
+  const buffer = Buffer.alloc(256);
+  for (let i = buffer.byteLength; i >= 0; i--) {
+    buffer[i] = i;
+  }
+  return buffer;
+};
+
+describe('decrypt/qmccache', () => {
+  it('should decrypt specified buffer correctly', () => {
+    const input = createInputBuffer();
+    DecryptQmcCacheBuffer(input);
+    expect(input).toEqual(expectedBuffer);
+  });
+});
diff --git a/src/decrypt/__test__/fixture/qmc_cache_expected.bin b/src/decrypt/__test__/fixture/qmc_cache_expected.bin
new file mode 100644
index 0000000000000000000000000000000000000000..a1a0f6de2e3c114841f8068a189ecd11f7416535
GIT binary patch
literal 256
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zXKQa07aJb~2MZ4~H#<KgCo3<~*4o~}#>&p}_WJ(f=IZW}mYSY|hKi1|wz|HermC(|
zR$5*{MoLa{c6xqdW@>H{78)J`1_}-`Hab2cCMqt`)!E&_#mUX__4)nb<>~E_m6@G^
zg^7)^wYj~arKzn^Rasp@MM+I@b$NYZWoc~@6&W1?1qlr?H90*YB`Gb?)Y#m>#K_F>
z^!WVX<ml{>l$e}=gouo=w79&Wq^PV=R9IX<L`Y0<ba;GVWN2&<6c`);1PBZ;G&npU
GBq%H&%YT6Y

literal 0
HcmV?d00001

diff --git a/src/decrypt/qmccache.ts b/src/decrypt/qmccache.ts
index dceb7cc..7d66ed5 100644
--- a/src/decrypt/qmccache.ts
+++ b/src/decrypt/qmccache.ts
@@ -1,50 +1,54 @@
-import {
-  AudioMimeType,
-  GetArrayBuffer,
-  GetCoverFromFile,
-  GetMetaFromFile,
-  SniffAudioExt,
-  SplitFilename,
-} from '@/decrypt/utils';
-
-import { Decrypt as QmcDecrypt, HandlerMap } from '@/decrypt/qmc';
-
-import { DecryptResult } from '@/decrypt/entity';
-
-import { parseBlob as metaParseBlob } from 'music-metadata-browser';
-
-export async function Decrypt(file: Blob, raw_filename: string, _: string): Promise<DecryptResult> {
-  const buffer = new Uint8Array(await GetArrayBuffer(file));
-  let length = buffer.length;
-  for (let i = 0; i < length; i++) {
-    buffer[i] ^= 0xf4;
-    if (buffer[i] <= 0x3f) buffer[i] = buffer[i] * 4;
-    else if (buffer[i] <= 0x7f) buffer[i] = (buffer[i] - 0x40) * 4 + 1;
-    else if (buffer[i] <= 0xbf) buffer[i] = (buffer[i] - 0x80) * 4 + 2;
-    else buffer[i] = (buffer[i] - 0xc0) * 4 + 3;
-  }
-  let ext = SniffAudioExt(buffer, '');
-  const newName = SplitFilename(raw_filename);
-  let audioBlob: Blob;
-  if (ext !== '' || newName.ext === 'mp3') {
-    audioBlob = new Blob([buffer], { type: AudioMimeType[ext] });
-  } else if (newName.ext in HandlerMap) {
-    audioBlob = new Blob([buffer], { type: 'application/octet-stream' });
-    return QmcDecrypt(audioBlob, newName.name, newName.ext);
-  } else {
-    throw '不支持的QQ音乐缓存格式';
-  }
-  const tag = await metaParseBlob(audioBlob);
-  const { title, artist } = GetMetaFromFile(raw_filename, tag.common.title, tag.common.artist);
-
-  return {
-    title,
-    artist,
-    ext,
-    album: tag.common.album,
-    picture: GetCoverFromFile(tag),
-    file: URL.createObjectURL(audioBlob),
-    blob: audioBlob,
-    mime: AudioMimeType[ext],
-  };
-}
+import {
+  AudioMimeType,
+  GetArrayBuffer,
+  GetCoverFromFile,
+  GetMetaFromFile,
+  SniffAudioExt,
+  SplitFilename,
+} from '@/decrypt/utils';
+
+import { Decrypt as QmcDecrypt, HandlerMap } from '@/decrypt/qmc';
+
+import { DecryptResult } from '@/decrypt/entity';
+
+import { parseBlob as metaParseBlob } from 'music-metadata-browser';
+
+export function DecryptBuffer(buffer: Uint8Array | Buffer) {
+  let length = buffer.byteLength;
+  for (let i = 0; i < length; i++) {
+    buffer[i] ^= 0xf4;
+    if (buffer[i] <= 0x3f) buffer[i] = buffer[i] * 4;
+    else if (buffer[i] <= 0x7f) buffer[i] = (buffer[i] - 0x40) * 4 + 1;
+    else if (buffer[i] <= 0xbf) buffer[i] = (buffer[i] - 0x80) * 4 + 2;
+    else buffer[i] = (buffer[i] - 0xc0) * 4 + 3;
+  }
+}
+
+export async function Decrypt(file: Blob, raw_filename: string, _: string): Promise<DecryptResult> {
+  const buffer = new Uint8Array(await GetArrayBuffer(file));
+  DecryptBuffer(buffer);
+  let ext = SniffAudioExt(buffer, '');
+  const newName = SplitFilename(raw_filename);
+  let audioBlob: Blob;
+  if (ext !== '' || newName.ext === 'mp3') {
+    audioBlob = new Blob([buffer], { type: AudioMimeType[ext] });
+  } else if (newName.ext in HandlerMap) {
+    audioBlob = new Blob([buffer], { type: 'application/octet-stream' });
+    return QmcDecrypt(audioBlob, newName.name, newName.ext);
+  } else {
+    throw '不支持的QQ音乐缓存格式';
+  }
+  const tag = await metaParseBlob(audioBlob);
+  const { title, artist } = GetMetaFromFile(raw_filename, tag.common.title, tag.common.artist);
+
+  return {
+    title,
+    artist,
+    ext,
+    album: tag.common.album,
+    picture: GetCoverFromFile(tag),
+    file: URL.createObjectURL(audioBlob),
+    blob: audioBlob,
+    mime: AudioMimeType[ext],
+  };
+}