✨ Add on track change event and automatic track waterfall

src/clients/discord/discord.module.ts

@@ -1,11 +1,12 @@
 import { Module } from '@nestjs/common';
 import { OnModuleDestroy } from '@nestjs/common/interfaces/hooks';
+import { PlaybackModule } from '../../playback/playback.module';
 import { DiscordConfigService } from './discord.config.service';
 import { DiscordMessageService } from './discord.message.service';
 import { DiscordVoiceService } from './discord.voice.service';
 
 @Module({
-  imports: [],
+  imports: [PlaybackModule],
   controllers: [],
   providers: [DiscordConfigService, DiscordVoiceService, DiscordMessageService],
   exports: [DiscordConfigService, DiscordVoiceService, DiscordMessageService],

src/clients/discord/discord.voice.service.ts

@@ -1,9 +1,9 @@
 import {
   AudioPlayer,
-  AudioPlayerPausedState,
   AudioPlayerStatus,
   AudioResource,
   createAudioPlayer,
+  createAudioResource,
   getVoiceConnection,
   getVoiceConnections,
   joinVoiceChannel,
@@ -11,8 +11,11 @@ import {
 } from '@discordjs/voice';
 import { Injectable } from '@nestjs/common';
 import { Logger } from '@nestjs/common/services';
+import { OnEvent } from '@nestjs/event-emitter';
 import { GuildMember } from 'discord.js';
 import { GenericTryHandler } from '../../models/generic-try-handler';
+import { PlaybackService } from '../../playback/playback.service';
+import { Track } from '../../types/track';
 import { DiscordMessageService } from './discord.message.service';
 
 @Injectable()
@@ -21,7 +24,16 @@ export class DiscordVoiceService {
   private audioPlayer: AudioPlayer;
   private voiceConnection: VoiceConnection;
 
-  constructor(private readonly discordMessageService: DiscordMessageService) {}
+  constructor(
+    private readonly discordMessageService: DiscordMessageService,
+    private readonly playbackService: PlaybackService,
+  ) {}
+
+  @OnEvent('playback.newTrack')
+  handleOnNewTrack(newTrack: Track) {
+    const resource = createAudioResource(newTrack.streamUrl);
+    this.playResource(resource);
+  }
 
   tryJoinChannelAndEstablishVoiceConnection(
     member: GuildMember,
@@ -156,6 +168,17 @@ export class DiscordVoiceService {
       this.audioPlayer.on('error', (message) => {
         this.logger.error(message);
       });
+      this.audioPlayer.on('stateChange', (statusChange) => {
+        if (statusChange.status !== AudioPlayerStatus.AutoPaused) {
+          return;
+        }
+
+        if (!this.playbackService.hasNextTrack()) {
+          return;
+        }
+
+        this.playbackService.nextTrack();
+      });
       this.voiceConnection.subscribe(this.audioPlayer);
       return this.audioPlayer;
     }

src/commands/play.comands.ts

@@ -29,6 +29,7 @@ import { DiscordVoiceService } from '../clients/discord/discord.voice.service';
 import { JellyfinStreamBuilderService } from '../clients/jellyfin/jellyfin.stream.builder.service';
 import { PlaybackService } from '../playback/playback.service';
 import { Constants } from '../utils/constants';
+import { trimStringToFixedLength } from '../utils/stringUtils';
 
 @Command({
   name: 'play',
@@ -69,9 +70,9 @@ export class PlayItemCommand
 
     const lines: string[] = firstItems.map(
       (item) =>
-        `:white_small_square: ${this.markSearchTermOverlap(
-          item.Name,
-          dto.search,
+        `:white_small_square: ${trimStringToFixedLength(
+          this.markSearchTermOverlap(item.Name, dto.search),
+          30,
         )} *(${item.Type})*`,
     );
 
@@ -104,7 +105,8 @@ export class PlayItemCommand
     return {
       embeds: [
         this.discordMessageService.buildMessage({
-          title: '',
+          title: 'a',
+          description: description,
           mixin(embedBuilder) {
             return embedBuilder.setAuthor({
               name: 'Jellyfin Search Results',
@@ -158,12 +160,6 @@ export class PlayItemCommand
 
     const artists = item.Artists.join(', ');
 
-    const addedIndex = this.playbackService.eneuqueTrack({
-      jellyfinId: item.Id,
-      name: item.Name,
-      durationInMilliseconds: milliseconds,
-    });
-
     const guildMember = interaction.member as GuildMember;
     const bitrate = guildMember.voice.channel.bitrate;
 
@@ -171,11 +167,16 @@ export class PlayItemCommand
       guildMember,
     );
 
-    this.jellyfinStreamBuilder
-      .buildStreamUrl(item.Id, bitrate)
-      .then((stream) => {
-        const resource = createAudioResource(stream);
-        this.discordVoiceService.playResource(resource);
+    const stream = await this.jellyfinStreamBuilder.buildStreamUrl(
+      item.Id,
+      bitrate,
+    );
+
+    const addedIndex = this.playbackService.eneuqueTrack({
+      jellyfinId: item.Id,
+      name: item.Name,
+      durationInMilliseconds: milliseconds,
+      streamUrl: stream,
     });
 
     await interaction.update({

src/playback/playback.service.ts

@@ -3,6 +3,7 @@ import { Playlist } from '../types/playlist';
 import { Track } from '../types/track';
 
 import { v4 as uuidv4 } from 'uuid';
+import { EventEmitter2 } from '@nestjs/event-emitter';
 
 @Injectable()
 export class PlaybackService {
@@ -11,6 +12,8 @@ export class PlaybackService {
     activeTrack: null,
   };
 
+  constructor(private readonly eventEmitter: EventEmitter2) {}
+
   getActiveTrack() {
     return this.getTrackById(this.playlist.activeTrack);
   }
@@ -38,6 +41,7 @@ export class PlaybackService {
 
     const newKey = keys[index + 1];
     this.setActiveTrack(newKey);
+    this.controlAudioPlayer();
     return true;
   }
 
@@ -51,6 +55,7 @@ export class PlaybackService {
     const keys = this.getTrackIds();
     const newKey = keys[index - 1];
     this.setActiveTrack(newKey);
+    this.controlAudioPlayer();
     return true;
   }
 
@@ -66,6 +71,7 @@ export class PlaybackService {
 
     if (emptyBefore) {
       this.setActiveTrack(this.playlist.tracks.find((x) => x.id === uuid).id);
+      this.controlAudioPlayer();
     }
 
     return this.playlist.tracks.findIndex((x) => x.id === uuid);
@@ -82,6 +88,10 @@ export class PlaybackService {
     this.playlist.tracks = [];
   }
 
+  hasNextTrack() {
+    return this.getActiveIndex() + 1 < this.getTrackIds().length;
+  }
+
   hasActiveTrack() {
     return this.playlist.activeTrack !== null;
   }
@@ -101,4 +111,11 @@ export class PlaybackService {
   private getActiveIndex() {
     return this.getTrackIds().indexOf(this.playlist.activeTrack);
   }
+
+  private controlAudioPlayer() {
+    const activeTrack = this.getActiveTrack();
+    console.log('received track change');
+    console.log(activeTrack.track);
+    this.eventEmitter.emit('playback.newTrack', activeTrack.track);
+  }
 }

src/types/track.ts

@@ -2,4 +2,5 @@ export interface Track {
   jellyfinId: string;
   name: string;
   durationInMilliseconds: number;
+  streamUrl: string;
 }

src/utils/stringUtils.ts

@@ -0,0 +1,9 @@
+export const trimStringToFixedLength = (value: string, maxLength: number) => {
+  if (maxLength < 1) {
+    throw new Error('max length must be positive');
+  }
+
+  return value.length > maxLength
+    ? value.substring(0, maxLength - 3) + '...'
+    : value;
+};