feat(playlist_track_all): 增加offset偏移量设置

module/playlist_track_all.js

@@ -10,6 +10,7 @@ module.exports = (query, request) => {
   //不放在data里面避免请求带上无用的数据
   let limit = query.limit
   let offset = parseInt(query.offset) || 0
+  let allOffset
   let trackIds
   let idsData = Object.create(null)
 
@@ -24,7 +25,11 @@ module.exports = (query, request) => {
     if (typeof limit === 'undefined') {
       limit = trackIds.length
     }
-
+    // 若offset超出最大偏移量则重置为最大偏移量
+    allOffset = trackIds.length / limit - 1
+    if (offset > allOffset) {
+      offset = allOffset
+    }
     trackIds.forEach((item, index) => {
       if (index >= limit * offset && index < limit * (offset + 1)) {
         ids.push(item.id)