Persist user data to local storage

src/app/appState.js

@@ -1,9 +1,9 @@
-class AppState {
-    constructor() {
-        this.emphasizeBytes = true;
+export default class AppState {
+    constructor(persistData) {
+        this.emphasizeBytes = persistData.emphasizeBytes || true;
         this.commandResults = [];
         this.handlers = [];
-        this.uiTheme = 'dark'
+        this.uiTheme = persistData.uiTheme || 'dark';
     }
 
     addCommandResult(result) {
@@ -35,7 +35,11 @@ class AppState {
          this.uiTheme = theme;
          this.triggerChanged();    
     }
-};
 
-var appState = new AppState();
-export default appState;
+    getPersistData() {
+        return {
+            emphasizeBytes: this.emphasizeBytes,
+            uiTheme: this.uiTheme 
+        }
+    }
+};

src/app/appStateStore.js

@@ -0,0 +1,26 @@
+const storeKey = 'AppState';
+
+export default {
+    getPersistedData() {
+        var json = window.localStorage.getItem(storeKey);
+        if(!json) {
+            return {};
+        }
+
+        try {
+            return JSON.parse(json);
+        }
+        catch(ex) {
+            console.error('Failed to parse AppState json. Json Value: \n' + json, ex);
+            return {};
+        }
+    },
+
+    watch (appState) {
+        appState.onChange(() => this.persistData(appState));
+    },
+
+    persistData(appState) {
+        localStorage.setItem(storeKey, JSON.stringify(appState.getPersistData()));
+    }
+}

src/app/commands.js

@@ -1,4 +1,3 @@
-import appState from './appState';
 import HelpResult from './models/HelpResult';
 import UnknownCommandResult from './models/UnknownCommandResult';
 import ExpressionResult from './models/ExpressionResult';
@@ -7,7 +6,7 @@ import * as expression from './expression';
 var cmdConfig = {};
 
 export default {
-    initialize (cmd) {
+    initialize (cmd, appState) {
 
             cmd.command({
                    canHandle: (input) => expression.parser.canParse(input),

src/app/index.jsx

@@ -1,12 +1,23 @@
 import React from 'react';
 import ReactDOM from 'react-dom';
 import InputBox from './components/InputBox.jsx';
-import appState from './appState';
+import AppState from './AppState';
+import appStateStore from './appStateStore';
 import cmd from './cmd';
 import commands from './commands';
 import AppRoot from './components/AppRoot';
 
-commands.initialize(cmd);
+
+var stateData = appStateStore.getPersistedData();
+const appState = new AppState(stateData);
+
+console.log('Loaded stateData', stateData);
+
+appStateStore.watch(appState);
+
+commands.initialize(cmd, appState);
+
+console.log("appState", appState);
 
 // cmd.execute('1');
 // cmd.execute('2');