1 files changed, 36 insertions, 0 deletions

diff --git a/client/src/app/app.service.ts b/client/src/app/app.service.ts
new file mode 100644
index 000000000..033c21900
--- /dev/null
+++ b/client/src/app/app.service.ts
@@ -0,0 +1,36 @@
+
+import { Injectable } from '@angular/core';
+
+@Injectable()
+export class AppState {
+  _state = { };
+
+  constructor() { ; }
+
+  // already return a clone of the current state
+  get state() {
+    return this._state = this._clone(this._state);
+  }
+  // never allow mutation
+  set state(value) {
+    throw new Error('do not mutate the `.state` directly');
+  }
+
+
+  get(prop?: any) {
+    // use our state getter for the clone
+    const state = this.state;
+    return state.hasOwnProperty(prop) ? state[prop] : state;
+  }
+
+  set(prop: string, value: any) {
+    // internally mutate our state
+    return this._state[prop] = value;
+  }
+
+
+  _clone(object) {
+    // simple object clone
+    return JSON.parse(JSON.stringify( object ));
+  }
+}