✨ feat: Seeking support

src/player/index.ts

@@ -16,7 +16,7 @@ export class Player {
         this.providers = providers;
     }
 
-    public async play(url: string) {
+    public async play(url: string, seekTime: number = 0) {
         if (!this.currentProvider) {
             const providers = this.providers.filter((provider) =>
                 provider.canPlay(url),
@@ -29,15 +29,25 @@ export class Player {
             this.currentProvider = providers[0];
         }
 
-        // TODO: Handle if already playing
-
         const information = await this.currentProvider.getInformation(url);
         //console.log(information);
 
         if (information.livestream)
             // TODO: Implement livestreams
             throw new Error("Livestreams are not supported yet");
-        else this._stream = new SeekableStream(information, url);
+
+        // If already playing, destroy the current stream
+        if (this._stream) {
+            this._stream.destroy();
+        }
+
+        this._stream = new SeekableStream(information, url, seekTime);
+    }
+
+    public async seek(time: number) {
+        if (!this._stream) throw new Error("No stream to seek");
+
+        await this.play(this._stream.referenceUrl, time);
     }
 
     public getCurrentSampleRate() {

src/utils/SeekableStream.ts

@@ -1,7 +1,7 @@
 import { Readable } from "stream";
 import { AudioInformation } from "../providers/base";
 import { Timer } from "./Timer";
-import { WebmSeeker } from "./WebmSeeker";
+import { WebmSeeker, WebmSeekerState } from "./WebmSeeker";
 import { getStream } from "./Request";
 
 const DEBUG_SIMULATE_FAILURE = false;
@@ -9,25 +9,30 @@ const DEBUG_SIMULATE_FAILURE = false;
 export class SeekableStream {
     private id: string;
     public information: AudioInformation;
-    private referenceUrl: string;
+    public readonly referenceUrl: string;
 
     public stream: WebmSeeker;
 
     private timer: Timer;
     private ticking: boolean = false;
     private locked: boolean = false;
+    private firstTick: boolean = true;
     private destroyed: boolean = false;
 
     private bytesReceived: number = 0;
     private bytesRead: number = 0;
     private bytesPerRequestLimit = 1 * 1024 * 1024; // 1 MB per request
 
-    constructor(information: AudioInformation, referenceUrl: string) {
+    constructor(
+        information: AudioInformation,
+        referenceUrl: string,
+        seekTime: number = 0,
+    ) {
         this.id = Math.random().toString(36).substring(8);
         this.information = information;
         this.referenceUrl = referenceUrl;
 
-        this.stream = new WebmSeeker(0, {
+        this.stream = new WebmSeeker(seekTime, {
             highWaterMark: 5 * 1024 * 1024,
         });
 
@@ -45,11 +50,10 @@ export class SeekableStream {
 
         this.timer.start();
         this.tick();
+        if (seekTime !== 0) this.seek();
     }
 
     private async tick() {
-        console.log(`[${this.id}] > Ticking...`);
-
         if (this.destroyed) {
             console.debug(
                 `[${this.id}] > Stream already destroyed, not ticking`,
@@ -60,6 +64,81 @@ export class SeekableStream {
 
         this.debugLog();
 
+        if (this.firstTick) {
+            this.firstTick = false;
+            this.locked = true;
+
+            // Get header
+            const rangeHeader = `bytes=${this.bytesReceived}-${this.information.indexRange.end}`;
+            const request = await getStream(this.information.url, {
+                headers: {
+                    range: rangeHeader,
+                },
+            }).catch((err: Error) => err);
+
+            console.debug(
+                `[${this.id}] > Request first tick header range | ${rangeHeader}`,
+            );
+
+            if (request instanceof Error) {
+                console.debug(
+                    `[${this.id}] > Request first tick error: ${request.message}`,
+                );
+                await this.refreshInformation();
+                this.timer.reset();
+                this.tick();
+
+                this.locked = false;
+                return;
+            }
+
+            // Simulate failed request 25% of the time
+            if (DEBUG_SIMULATE_FAILURE && Math.random() < 0.25) {
+                console.debug(`[${this.id}] > Simulating request failure`);
+                request.status = 416;
+            }
+
+            if (request.status >= 400) {
+                console.debug(
+                    `[${this.id}] > Request first tick failed with status ${request.status}`,
+                );
+                await this.refreshInformation();
+                this.timer.reset();
+                this.tick();
+
+                this.locked = false;
+                return;
+            }
+
+            if (!request.data) {
+                this.timer.reset();
+                this.tick();
+
+                this.locked = false;
+                return;
+            }
+
+            console.debug(`[${this.id}] > Request first tick successful`);
+
+            const incomingStream = request.data;
+
+            incomingStream.on("data", (chunk: any) => {
+                this.stream.push(chunk);
+                this.bytesReceived += chunk.length;
+            });
+
+            incomingStream.on("end", async () => {
+                console.debug(`[${this.id}] > Header received, unlocking`);
+                this.locked = false;
+                incomingStream.destroy();
+                this.debugLog();
+
+                this.locked = false;
+            });
+
+            return;
+        }
+
         const isBufferSufficient =
             this.stream.readableLength >= this.bytesPerRequestLimit;
 
@@ -147,6 +226,7 @@ export class SeekableStream {
         }
 
         if (
+            !this.locked &&
             this.bytesReceived >= this.information.fileSize &&
             this.stream.readableLength === 0
         ) {
@@ -154,8 +234,78 @@ export class SeekableStream {
             this.destroy();
             return;
         }
+    }
 
-        console.debug(`[${this.id}] > Tick completed`);
+    public async seek(): Promise<boolean> {
+        const parse = await new Promise(async (resolve, reject) => {
+            if (!this.stream.headerparsed) {
+                console.debug(`[${this.id}] > Parsing header...`);
+                console.debug(
+                    `[${this.id}] > Requesting range | 0-${this.information.indexRange.end}`,
+                );
+
+                let req = await getStream(this.information.url, {
+                    headers: {
+                        range: `bytes=0-${this.information.indexRange.end}`,
+                    },
+                }).catch((err: Error) => err);
+
+                if (req instanceof Error || req.status >= 400) {
+                    reject(false);
+                    return;
+                }
+
+                const incomingStream = req.data;
+                incomingStream.pipe(this.stream, { end: false });
+
+                this.stream.once("headComplete", () => {
+                    console.debug(`[${this.id}] > Header parsed, unpiping...`);
+                    incomingStream.unpipe(this.stream);
+                    incomingStream.destroy();
+                    this.stream.state = WebmSeekerState.READING_DATA;
+                    resolve(true);
+                });
+            }
+
+            resolve(true);
+        }).catch((err) => err);
+
+        if (parse instanceof Error || parse === false) {
+            await this.refreshInformation();
+            this.timer.reset();
+            return this.seek();
+        }
+
+        // Wait for lock to be released
+        while (this.locked) {
+            await new Promise((resolve) => setTimeout(resolve, 100));
+        }
+
+        this.locked = true;
+
+        const bytes = this.stream.seek(this.information.fileSize);
+        if (bytes instanceof Error) {
+            // TODO: Handle seek error
+            this.destroy();
+            return false;
+        }
+
+        console.debug(
+            `[${this.id}] > Seeking... Byte located at ${bytes} / ${this.information.fileSize}`,
+        );
+
+        // Offset the counter
+        this.bytesReceived = bytes;
+        this.bytesRead = bytes;
+
+        this.stream.seekfound = false;
+        this.locked = false;
+
+        // Tick to start fetching data
+        this.timer.reset();
+        this.tick();
+
+        return true;
     }
 
     private getCurrentTimestamp() {
@@ -177,10 +327,14 @@ export class SeekableStream {
         this.stream.on(event, listener);
     }
 
-    private destroy() {
+    public destroy() {
         console.debug(`[${this.id}] > Stream destroyed`);
         if (!this.timer.isDestroyed()) this.timer.destroy();
-        if (this.stream) this.stream.destroy();
+        if (this.stream) {
+            this.stream.end();
+            this.stream.destroy();
+        }
+
         this.destroyed = true;
     }
 

src/utils/WebmSeeker.ts

@@ -766,6 +766,7 @@ export class WebmSeeker extends Duplex {
             position = 0;
         let time_left = (this.sec - this.time) * 1000 || 0;
         time_left = Math.round(time_left / 20) * 20;
+
         if (!this.header.segment.cues) return new Error("Failed to Parse Cues");
 
         for (let i = 0; i < this.header.segment.cues.length; i++) {
@@ -781,6 +782,14 @@ export class WebmSeeker extends Duplex {
             } else continue;
         }
         if (clusterlength === 0) return position;
+
+        console.debug(
+            `[WebmSeeker] > Seeking to ${this.sec} seconds, ${
+                this.offset +
+                Math.round(position + (time_left / 20) * (clusterlength / 500))
+            } bytes`,
+        );
+
         return (
             this.offset +
             Math.round(position + (time_left / 20) * (clusterlength / 500))
@@ -810,6 +819,8 @@ export class WebmSeeker extends Duplex {
     private readHead(): Error | undefined {
         if (!this.chunk) return new Error("Chunk is missing");
 
+        console.debug("[WebmSeeker] > Reading Head");
+
         while (this.chunk.length > this.cursor) {
             const oldCursor = this.cursor;
             const id = this.vint_length;
@@ -870,6 +881,9 @@ export class WebmSeeker extends Duplex {
         }
         this.remaining = this.chunk.slice(this.cursor);
         this.cursor = 0;
+
+        console.debug("[WebmSeeker] > Finished Reading Head");
+        this.emit("headComplete");
     }
 
     private readTag(): Error | undefined {