add "add/remove to library" in playlist view

src/renderer/views/pages/cider-playlist.ejs

@@ -55,6 +55,10 @@
                                 @click="app.mk.shuffleMode = 1;app.playMediaItemById(data.attributes.playParams.id ?? data.id, data.attributes.playParams.kind ?? data.type, data.attributes.playParams.isLibrary ?? false, data.attributes.url)">
                             Shuffle
                         </button>
+                        <button class="wr-btn" style="min-width: 120px;" 
+                        @click="(!inLibrary) ? addToLibrary(data.attributes.playParams.id.toString()) : removeFromLibrary(data.attributes.playParams.id.toString())">
+                          {{ (!inLibrary) ? "Add to Library" : "Remove from Library" }}
+                       </button>
                     </div>
                 </div>
             </div>
@@ -89,17 +93,40 @@
             return {
                 editorialNotesExpanded: false,
                 drag: false,
-                nameEditing: false
+                nameEditing: false,
+                inLibrary: null
             }
         },
-        mounted() {
+        mounted: function () {
-
+            this.isInLibrary()
+        },
+        watch:{
+           data : function() {
+            this.isInLibrary()
+            }
         },
         methods: {
+             async isInLibrary () {
+                 if (this.data.type && !this.data.type.includes('library')){
+                    // please keep using vars here
+                 var params = {"fields[albums]": "inLibrary","relate" : "library"}
+                 var res = await app.mkapi(this.data.attributes.playParams.kind ?? this.data.type, false , this.data.attributes.playParams.id ?? this.data.id, params);    
+                 this.inLibrary = (res && res.attributes && res.attributes.inLibrary) ? res.attributes.inLibrary : false} else {this.inLibrary = true}
+            },
             editPlaylist() {
                 app.editPlaylist(this.data.id, this.data.attributes.name);
                 this.nameEditing = false
             },
+            addToLibrary(id) {
+                app.mk.addToLibrary(id)
+                this.inLibrary = true
+            },
+            removeFromLibrary(id) {                
+                let kind = this.data.attributes.playParams.kind ?? this.data.type ?? '';
+                var truekind = (!kind.endsWith("s")) ? (kind + "s") : kind;
+                app.mk.api.library.remove({[truekind]: this.data.id ?? this.data.attributes.playParams.id })
+                this.inLibrary = false
+            },
             editPlaylistName() {
                 if(this.data.attributes.canEdit && this.data.type == "library-playlists") {
                     this.nameEditing = true