From 035737312360279efd5026b225f30ef14aa55abf Mon Sep 17 00:00:00 2001
From: Max Isom <code@maxisom.me>
Date: Wed, 18 Mar 2020 19:17:47 -0500
Subject: [PATCH] Limit playlist adds to 50 songs

---
 package.json              |  1 +
 src/commands/play.ts      | 19 ++++++++++++++++---
 src/services/get-songs.ts | 23 ++++++++++++++++++-----
 yarn.lock                 | 12 ++++++++++++
 4 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/package.json b/package.json
index c37da7e..0472ca3 100644
--- a/package.json
+++ b/package.json
@@ -85,6 +85,7 @@
     "spotify-uri": "^2.0.0",
     "spotify-web-api-node": "^4.0.0",
     "sqlite3": "^4.1.1",
+    "unique-random-array": "^2.0.0",
     "youtube.ts": "^0.1.1",
     "ytdl-core": "^2.0.0",
     "ytsr": "^0.1.11"
diff --git a/src/commands/play.ts b/src/commands/play.ts
index bcafdbf..eceac94 100644
--- a/src/commands/play.ts
+++ b/src/commands/play.ts
@@ -71,6 +71,7 @@ export default class implements Command {
     }
 
     const newSongs: QueuedSong[] = [];
+    let extraMsg = '';
 
     // Test if it's a complete URL
     try {
@@ -95,7 +96,15 @@ export default class implements Command {
           }
         }
       } else if (url.protocol === 'spotify:' || url.host === 'open.spotify.com') {
-        const [convertedSongs] = await this.getSongs.spotifySource(args[0]);
+        const [convertedSongs, nSongsNotFound, totalSongs] = await this.getSongs.spotifySource(args[0]);
+
+        if (totalSongs > 50) {
+          extraMsg = 'a random sample of 50 songs was taken';
+        }
+
+        if (nSongsNotFound !== 0) {
+          extraMsg += `and ${nSongsNotFound.toString()} songs were not found`;
+        }
 
         newSongs.push(...convertedSongs);
       }
@@ -122,10 +131,14 @@ export default class implements Command {
 
     const firstSong = newSongs[0];
 
+    if (extraMsg !== '') {
+      extraMsg = ` (${extraMsg})`;
+    }
+
     if (newSongs.length === 1) {
-      await res.stop(`u betcha, **${firstSong.title}** added to the queue`);
+      await res.stop(`u betcha, **${firstSong.title}** added to the queue${extraMsg}`);
     } else {
-      await res.stop(`u betcha, **${firstSong.title}** and ${newSongs.length - 1} other songs were added to the queue`);
+      await res.stop(`u betcha, **${firstSong.title}** and ${newSongs.length - 1} other songs were added to the queue${extraMsg}`);
     }
 
     if (this.playerManager.get(msg.guild!.id).voiceConnection === null) {
diff --git a/src/services/get-songs.ts b/src/services/get-songs.ts
index 19fc6c0..347d9d6 100644
--- a/src/services/get-songs.ts
+++ b/src/services/get-songs.ts
@@ -7,6 +7,7 @@ import Spotify from 'spotify-web-api-node';
 import ytsr from 'ytsr';
 import YouTube from 'youtube.ts';
 import pLimit from 'p-limit';
+import uniqueRandomArray from 'unique-random-array';
 import {QueuedSong, QueuedPlaylist} from '../services/queue';
 import {TYPES} from '../types';
 
@@ -77,10 +78,10 @@ export default class {
     });
   }
 
-  async spotifySource(url: string): Promise<[QueuedSong[], number]> {
+  async spotifySource(url: string): Promise<[QueuedSong[], number, number]> {
     const parsed = spotifyURI.parse(url);
 
-    const tracks: SpotifyApi.TrackObjectSimplified[] = [];
+    let tracks: SpotifyApi.TrackObjectSimplified[] = [];
 
     let playlist: QueuedPlaylist | null = null;
 
@@ -137,12 +138,24 @@ export default class {
       }
 
       default: {
-        return [[], 0];
+        return [[], 0, 0];
+      }
+    }
+
+    // Get 50 random songs if many
+    const originalNSongs = tracks.length;
+
+    if (tracks.length > 50) {
+      const random = uniqueRandomArray(tracks);
+
+      tracks = [];
+      for (let i = 0; i < 50; i++) {
+        tracks.push(random());
       }
     }
 
     // Limit concurrency so hopefully we don't get banned for searching
-    const limit = pLimit(3);
+    const limit = pLimit(5);
     let songs = await Promise.all(tracks.map(async track => limit(async () => this.spotifyToYouTube(track, playlist))));
 
     let nSongsNotFound = 0;
@@ -158,7 +171,7 @@ export default class {
       return accum;
     }, []);
 
-    return [songs as QueuedSong[], nSongsNotFound];
+    return [songs as QueuedSong[], nSongsNotFound, originalNSongs];
   }
 
   private async spotifyToYouTube(track: SpotifyApi.TrackObjectSimplified, playlist: QueuedPlaylist | null): Promise<QueuedSong | null> {
diff --git a/yarn.lock b/yarn.lock
index 0c74bda..5aab5c8 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2805,6 +2805,18 @@ undefsafe@^2.0.2:
   dependencies:
     debug "^2.2.0"
 
+unique-random-array@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/unique-random-array/-/unique-random-array-2.0.0.tgz#9e639b1a9dc141e97350a6fc6f17da4b0717b1ad"
+  integrity sha512-xR87O95fZ7hljw84J8r1YDXrvffPLWN513BNOP4Bv0KcgG5dyEUrHwsvP7mVAOKg4Y80uqRbpUk0GKr8il70qg==
+  dependencies:
+    unique-random "^2.1.0"
+
+unique-random@^2.1.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/unique-random/-/unique-random-2.1.0.tgz#7a8413da5176d028567168b57125ac5c0cec5c25"
+  integrity sha512-iQ1ZgWac3b8YxGThecQFRQiqgk6xFERRwHZIWeVVsqlbmgCRl0PY13R4mUkodNgctmg5b5odG1nyW/IbOxQTqg==
+
 unique-string@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/unique-string/-/unique-string-1.0.0.tgz#9e1057cca851abb93398f8b33ae187b99caec11a"