remove mpv dep, convert aac to flac

src/helpers/utils.ts

@@ -1,4 +1,8 @@
 import { FlacStreamTagger } from "flac-stream-tagger";
+import Ffmpeg from "fluent-ffmpeg";
+import ffmpegPath from "ffmpeg-static";
+
+Ffmpeg.setFfmpegPath(ffmpegPath || "");
 
 export default class {
     authHeaders: { [key: string]: string }
@@ -7,10 +11,28 @@ export default class {
         this.authHeaders = authHeaders
     }
 
+    async convertAacToFlac(buffer: ArrayBuffer) {
+        const fileId = Bun.nanoseconds().toString(36);
+
+        Bun.write(`tmp/${fileId}.aac`, Buffer.from(buffer))
+
+        Ffmpeg(`tmp/${fileId}.aac`)
+            .format('flac')
+            .run();
+
+        await Bun.file(`tmp/${fileId}.aac`).delete();
+        const flac = Bun.file(`tmp/${fileId}.flac`)
+        const audioBuffer = await flac.arrayBuffer();
+        await flac.delete()
+
+        return audioBuffer;
+    }
+
     async fetchTrack(id: number) {
         const audio = await fetch(`https://api.tidal.com/v1/tracks/${id}/playbackinfopostpaywall/v4?audioquality=HI_RES_LOSSLESS&playbackmode=STREAM&assetpresentation=FULL`, {
             headers: this.authHeaders
         })
+
         return await audio.json() as {
             trackId: number,
             audioPresentation: string,
@@ -41,7 +63,7 @@ export default class {
         if (manifestMimeType === "application/dash+xml") {
             await Bun.write(`tmp/${id}.mpd`, Buffer.from(manifest, "base64").toString("utf-8"))
 
-            await Bun.$`mpv --ao=null --stream-record=tmp/${id}.flac --speed=100 tmp/${id}.mpd`.quiet()
+            await Bun.$`${ffmpegPath} -protocol_whitelist https,file,tls,tcp -i tmp/${id}.mpd -c:a copy tmp/${id}.flac`.quiet()
 
             await Bun.file(`tmp/${id}.mpd`).delete();
 
@@ -51,7 +73,7 @@ export default class {
 
             await flac.delete()
 
-            return audioBuffer;
+            return { buffer: audioBuffer, mimeType: "audio/flac" }
         } else if (manifestMimeType === "application/vnd.tidal.bts") {
             const data = JSON.parse(Buffer.from(manifest, "base64").toString("utf-8")) as {
                 "mimeType": string,
@@ -62,13 +84,19 @@ export default class {
 
             const flac = await fetch(data.urls[0])
 
-            return await flac.arrayBuffer();
+            return { buffer: await flac.arrayBuffer(), mimeType: data.mimeType }
         }
 
-        return new ArrayBuffer(0);
+        return { buffer: new ArrayBuffer(0), mimeType: "" } // TODO: Handle other mime types
     }
 
-    async tagFlac(id: number, audioBuffer: ArrayBuffer) {
+    async tagFlac(id: number, audioBuffer: { buffer: ArrayBuffer, mimeType: string }) {
+        const fileId = Bun.nanoseconds().toString(36);
+
+        if (audioBuffer.mimeType === "audio/mp4") {
+            audioBuffer.buffer = await this.convertAacToFlac(audioBuffer.buffer) as ArrayBuffer;
+        }
+
         const trackReq = await fetch(`https://api.tidal.com/v1/tracks/${id}/?countryCode=US`, {
             headers: this.authHeaders
         })
@@ -113,7 +141,7 @@ export default class {
             ],
         }
 
-        return FlacStreamTagger.fromBuffer(Buffer.from(audioBuffer), {
+        return FlacStreamTagger.fromBuffer(Buffer.from(audioBuffer.buffer), {
             tagMap: {
                 title: track.title,
                 trackNumber: track.trackNumber.toString(),