Stores environmnets in tree

app/assets/javascripts/environments/environments_bundle.js.es6

@@ -40,7 +40,7 @@ $(() => {
      */
     ready() {
       gl.environmentsService.all().then((resp) => {
-        Store.addEnvironments(resp.json());
+        Store.storeEnvironments(resp.json());
 
         this.loading = false;
       });

app/assets/javascripts/environments/stores/environmnets_store.js.es6

@@ -3,19 +3,58 @@
   window.gl.environmentsList = window.gl.environmentsList || {};
   
   gl.environmentsList.EnvironmentsStore = {
+    state: {},
     
     create () {
-
+      this.state.environments = [];
     },
     
     /**
-     * Stores the received environmnets.
+     * In order to display a tree view we need to modify the received 
+     * data in to a tree structure based on `environment_type` 
+     * sorted alphabetically.
      * 
+     * @example
+     * it will transform this:
+     * [
+     *   { name: "environment", environment_type: "review" },
+     *   { name: "environment_1", environment_type: null }
+     *   { name: "environment_2, environment_type: "review" }
+     * ]
+     * into this:
+     * [
+     *   { name: "review", children: 
+     *      [
+     *        { name: "environment", environment_type: "review"},
+     *        { name: "environment_2", environment_type: "review"}
+     *      ]
+     *   },
+     *  {name: "environment_1", environment_type: null}
+     * ]
      * @param  {Array} environments List of environments
-     * @return {type}
      */
-    addEnvironments(environments) {
-      console.log(environments);
+    storeEnvironments(environments) {
+      this.state.environments = environments.reduce((acc, environment) => {
+        if (environment.environment_type !== null) {
+          const occurs = acc.find((element, index, array) => {
+            return element.name === environment.environment_type;
+          });
+
+          if (occurs !== undefined) {
+            acc[acc.indexOf(occurs)].children.push(environment);
+            acc[acc.indexOf(occurs)].children.sort();
+          } else {
+            acc.push({
+              name: environment.environment_type,
+              children: [environment]
+            });
+          }
+        } else {
+          acc.push(environment);
+        }
+
+        return acc;
+      }, []).sort();
     }
   }
 })();
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