refactor(decrypt/qmc): typescript

src/decrypt/qmc.ts

@@ -0,0 +1,156 @@
+import {QmcMask, QmcMaskDetectMflac, QmcMaskDetectMgg, QmcMaskGetDefault} from "./qmcMask";
+import {fromByteArray as Base64Encode, toByteArray as Base64Decode} from 'base64-js'
+import {
+    AudioMimeType,
+    GetArrayBuffer,
+    GetCoverFromFile,
+    GetImageFromURL,
+    GetMetaFromFile, IXAREA_API_ENDPOINT,
+    SniffAudioExt, WriteMetaToFlac, WriteMetaToMp3
+} from "@/decrypt/utils.ts";
+import {parseBlob as metaParseBlob} from "music-metadata-browser";
+
+
+import iconv from "iconv-lite";
+
+interface Handler {
+    ext: string
+    detect: boolean
+
+    handler(data?: Uint8Array): QmcMask | undefined
+}
+
+const HandlerMap: { [key: string]: Handler } = {
+    "mgg": {handler: QmcMaskDetectMgg, ext: "ogg", detect: true},
+    "mflac": {handler: QmcMaskDetectMflac, ext: "flac", detect: true},
+    "qmc0": {handler: QmcMaskGetDefault, ext: "mp3", detect: false},
+    "qmc2": {handler: QmcMaskGetDefault, ext: "ogg", detect: false},
+    "qmc3": {handler: QmcMaskGetDefault, ext: "mp3", detect: false},
+    "qmcogg": {handler: QmcMaskGetDefault, ext: "ogg", detect: false},
+    "qmcflac": {handler: QmcMaskGetDefault, ext: "flac", detect: false},
+    "bkcmp3": {handler: QmcMaskGetDefault, ext: "mp3", detect: false},
+    "bkcflac": {handler: QmcMaskGetDefault, ext: "flac", detect: false},
+    "tkm": {handler: QmcMaskGetDefault, ext: "m4a", detect: false},
+    "666c6163": {handler: QmcMaskGetDefault, ext: "flac", detect: false},
+    "6d7033": {handler: QmcMaskGetDefault, ext: "mp3", detect: false},
+    "6f6767": {handler: QmcMaskGetDefault, ext: "ogg", detect: false},
+    "6d3461": {handler: QmcMaskGetDefault, ext: "m4a", detect: false},
+    "776176": {handler: QmcMaskGetDefault, ext: "wav", detect: false}
+};
+
+export async function Decrypt(file: File, raw_filename: string, raw_ext: string) {
+    if (!(raw_ext in HandlerMap)) throw "File type is incorrect!";
+    const handler = HandlerMap[raw_ext];
+
+    const fileData = new Uint8Array(await GetArrayBuffer(file));
+    let audioData, seed, keyData;
+    if (handler.detect) {
+        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(keyPos, keyPos + keyLen);
+        if (!seed) seed = await queryKeyInfo(keyData, raw_filename, raw_ext);
+        if (!seed) throw raw_ext + "格式仅提供实验性支持";
+    } else {
+        audioData = fileData;
+        seed = handler.handler(audioData) as QmcMask;
+    }
+    let musicDecoded = seed.Decrypt(audioData);
+
+    const ext = SniffAudioExt(musicDecoded, handler.ext);
+    const mime = AudioMimeType[ext];
+
+    let musicBlob = new Blob([musicDecoded], {type: mime});
+
+    const musicMeta = await metaParseBlob(musicBlob);
+    for (let metaIdx in musicMeta.native) {
+        if (!musicMeta.native.hasOwnProperty(metaIdx)) continue
+        if (musicMeta.native[metaIdx].some(item => item.id === "TCON" && item.value === "(12)")) {
+            console.warn("try using gbk encoding to decode meta")
+            musicMeta.common.artist = iconv.decode(new Buffer(musicMeta.common.artist ?? ""), "gbk");
+            musicMeta.common.title = iconv.decode(new Buffer(musicMeta.common.title ?? ""), "gbk");
+            musicMeta.common.album = iconv.decode(new Buffer(musicMeta.common.album ?? ""), "gbk");
+        }
+    }
+
+    const info = GetMetaFromFile(raw_filename, musicMeta.common.title, musicMeta.common.artist)
+    if (keyData) reportKeyUsage(keyData, seed.getMatrix128(),
+        raw_filename, raw_ext, info.title, info.artist, musicMeta.common.album);
+
+    let imgUrl = GetCoverFromFile(musicMeta);
+    if (!imgUrl) {
+        imgUrl = await queryAlbumCoverImage(info.title, info.artist, musicMeta.common.album);
+        if (imgUrl !== "") {
+            const imageInfo = await GetImageFromURL(imgUrl);
+            if (imageInfo) {
+                imgUrl = imageInfo.url
+                try {
+                    const newMeta = {picture: imageInfo.buffer, title: info.title, artists: info.artist?.split(" _ ")}
+                    if (ext === "mp3") {
+                        musicDecoded = WriteMetaToMp3(Buffer.from(musicDecoded), newMeta, musicMeta)
+                        musicBlob = new Blob([musicDecoded], {type: mime});
+                    } else if (ext === 'flac') {
+                        musicDecoded = WriteMetaToFlac(Buffer.from(musicDecoded), newMeta, musicMeta)
+                        musicBlob = new Blob([musicDecoded], {type: mime});
+                    } else {
+                        console.info("writing metadata for " + ext + " is not being supported for now")
+                    }
+                } catch (e) {
+                    console.warn("Error while appending cover image to file " + e)
+                }
+            }
+        }
+    }
+    return {
+        status: true,
+        title: info.title,
+        artist: info.artist,
+        ext: ext,
+        album: musicMeta.common.album,
+        picture: imgUrl,
+        file: URL.createObjectURL(musicBlob),
+        mime: mime
+    }
+}
+
+
+function reportKeyUsage(keyData: Uint8Array, maskData: number[], filename: string, format: string, title: string, artist?: string, album?: string) {
+    fetch(IXAREA_API_ENDPOINT + "/qmcmask/usage", {
+        method: "POST",
+        headers: {"Content-Type": "application/json"},
+        body: JSON.stringify({
+            Mask: Base64Encode(new Uint8Array(maskData)), Key: Base64Encode(keyData),
+            Artist: artist, Title: title, Album: album, Filename: filename, Format: format
+        }),
+    }).then().catch()
+}
+
+async function queryKeyInfo(keyData: Uint8Array, filename: string, format: string) {
+    try {
+        const resp = await fetch(IXAREA_API_ENDPOINT + "/qmcmask/query", {
+            method: "POST",
+            headers: {"Content-Type": "application/json"},
+            body: JSON.stringify({Format: format, Key: Base64Encode(keyData), Filename: filename, Type: 44}),
+        });
+        let data = await resp.json();
+        return new QmcMask(Base64Decode(data.Matrix44));
+    } catch (e) {
+        console.log(e);
+    }
+}
+
+async function queryAlbumCoverImage(title: string, artist?: string, album?: string) {
+    const song_query_url = "https://stats.ixarea.com/apis" + "/music/qq-cover"
+    try {
+        const params = new URLSearchParams([["Title", title], ["Artist", artist ?? ""], ["Album", album ?? ""]])
+        const resp = await fetch(`${song_query_url}?${params.toString()}`)
+        if (resp.ok) {
+            let data = await resp.json();
+            return song_query_url + "/" + data.Type + "/" + data.Id
+        }
+    } catch (e) {
+        console.log(e);
+    }
+    return "";
+}