added selection methods

whatsapp-web.js/src/models/entity.js

@@ -4,12 +4,14 @@ class Entity {
     
     constructor(){
         this.data = new Map();  
+        this.selectedData = null;
         this.count = 0;
     }
 
     addData(key ,value){
         if(!this.isData(key)){
             this.data.set(key, value);
+            this.selectedData = key;
             return true;
         }
         return false;
@@ -26,16 +28,40 @@ class Entity {
     deleteData(key){
         if(this.isData(key)){
             this.data.delete(key);
+            if(this.selectedData == key){
+                this.selectedData = null;
+            }
             return true;
         }
         return false;
     }
 
     clearData(){
+        this.selectedData = null;
         this.data = new Map();
         this.count = 0;
     }
 
+    /**
+     * Select a specific data with its key
+     * @param {string} key 
+     * @returns true if a data is selected 
+     * @returns false if data is null
+     */
+    selectData(key){
+        if(this.isData(key))
+        {
+            this.selectedData = key;
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * 
+     * @param {string} key 
+     * @returns the value mapped to the key
+     */
     getData(key){
         if(this.isData(key)){
             return this.data.get(key);
@@ -43,6 +69,9 @@ class Entity {
         return null;
     }
 
+    /**
+     * @returns a map of all data
+     */
     getAllData(){
         return this.data;
     }