music: add --offset=<number> for playlists

src/modules/music.js

@@ -50,7 +50,13 @@ async function getSoundcloudClientID() {
   return null;
 }
 
-async function processPlaylist(url, type, shuffle = false, limit = -1) {
+async function processPlaylist(
+  url,
+  type,
+  shuffle = false,
+  limit = -1,
+  offset = 0
+) {
   let playlist;
 
   if (type === "yt") {
@@ -108,6 +114,10 @@ async function processPlaylist(url, type, shuffle = false, limit = -1) {
     shuffleArray(playlist);
   }
 
+  if (offset > 0) {
+    playlist = playlist.slice(offset);
+  }
+
   if (limit > 0) {
     playlist = playlist.slice(0, limit);
   }
@@ -395,6 +405,12 @@ command.callback = async function (msg, line) {
           argStr = argStr.replace(/--limit=(\d+)/, "").trim();
         }
 
+        let offset = 0;
+        if (argStr.match(/--offset=(\d+)/)) {
+          offset = argStr.match(/--offset=(\d+)/)[1];
+          argStr = argStr.replace(/--offset=(\d+)/, "").trim();
+        }
+
         let type;
         let playlist = false;
 
@@ -439,7 +455,8 @@ command.callback = async function (msg, line) {
               argStr,
               type,
               shuffle,
-              limit
+              limit,
+              offset
             );
             await statusMessage.edit({
               embeds: [