Better design and lots of little fixes all over.

sass/_variables.scss

@@ -37,9 +37,9 @@ $bg-color-dark: darken($bg-color, 10%) !default;
 $bg-color-light: lighten($bg-color, 10%) !default;
 
 // Control colors
-$success-color: #32b643 !default;
+$success-color: $green !default;
-$warning-color: $green !default;
+$warning-color: $yellow !default;
-$error-color: #e85600 !default;
+$error-color: $red !default;
 
 // Other colors
 $code-color: $green !default;
@@ -74,7 +74,7 @@ $unit-12: 2.4rem !default;
 $unit-16: 3.2rem !default;
 
 // Font sizes
-$html-font-size: 25px !default;
+$html-font-size: 16px !default;
 $html-line-height: 1.5 !default;
 $font-size: 1rem !default;
 $font-size-sm: .9rem !default;

src/components/Footer.svelte

@@ -7,7 +7,7 @@
 
   #footer {
     border-top: 1px solid $primary-color;
-    background-color: $gray-color-light;
+    background-color: $gray-color;
   }
 
   #right-column {
@@ -17,7 +17,8 @@
   #footer .panel {
     border: 0px;
     border-radius: 0px;
-    font-size: $font-size-sm;
+    font-size: 20px !important;
+    text-shadow: 2px 2px $gray-color-dark;
   }
 </style>
 
@@ -33,7 +34,7 @@
   </div>
 
   <div class="column col-3" id="right-column">
-    <a alt="Twitter @lzsthw" aria-label="Twitter @lzsthw" rel="external" href="https://twitter.com/lzsthw"><Icon size="48" name="twitter" /></a>
+    <a alt="Twitter @lzsthw" aria-label="Twitter @lzsthw" rel="external" href="https://twitter.com/lzsthw"><Icon size="48" name="twitter" light={true} /></a>
-      <a alt="The git repository" aria-label="The git repository" rel="external" href="https://git.learnjsthehardway.com/zedshaw/buttons-computer"><Icon size="48" name="code" /></a>
+      <a alt="The git repository" aria-label="The git repository" rel="external" href="https://git.learnjsthehardway.com/zedshaw/buttons-computer"><Icon size="48" name="code"  light={true} /></a>
   </div>
 </div>

src/components/Nav.svelte

@@ -0,0 +1,48 @@
+<script>
+  export let segment;
+  import { goto } from '@sapper/app';
+  import Icon from './Icon.svelte';
+</script>
+
+<style lang="scss">
+  @import "sass/_variables";
+
+  #logo {
+    font-size: 24px;
+    text-shadow: 2px 2px $gray-color-dark;
+  }
+
+  .menu-item .active {
+    background-color: $red;
+  }
+
+  .btn {
+    background-color: $red !important;
+    margin-left: 4px;
+    border: 1px solid $black;
+    height: 40px;
+  }
+
+  .navbar {
+    background-color: $gray-color;
+    min-height: 50px;
+  }
+</style>
+
+<header class="navbar">
+  <section class="navbar-section">
+    <a class="navbar-brand mr-2" href="/">
+      <div id="logo">BUTTONS</div>
+    </a>
+  </section>
+
+  <section class="navbar-section">
+    <a data-testid='nav-home-icon' rel="prefetch" class:btn-link="{ segment != undefined }" class="btn" href="/" alt="Home" aria-label="Home">
+      <Icon name="home" size="32" tooltip="Home" tooltip_bottom={true} light={true}/>
+    </a>
+    <a data-testid='nav-blog-icon' rel="external" class:btn-link="{ segment != 'blog' }" class="btn" href="https://learnjsthehardway.com/blog" alt="Read the blog" aria-label="Read the blog">
+      <Icon name="book-open" size="32" tooltip="Blog" tooltip_bottom={true} light={true} />
+    </a>
+  </section>
+</header>
+

src/components/Sidebar.svelte

@@ -1,7 +1,8 @@
 <script>
   import { ButtonMachine } from 'buttons';
 
-  let ops = ButtonMachine.operations();
+  const ops = ButtonMachine.operations();
+  const registers = ButtonMachine.register_names();
 
 </script>
 
@@ -16,5 +17,10 @@ OPERATIONS:
 {#each ops as op}
 { op + '\n'}
 {/each}
+
+REGISTERS:
+{#each registers as reg}
+{ reg + '\n'}
+{/each}
 </code>
 </pre>

src/node_modules/buttons.js

@@ -27,6 +27,11 @@ class ButtonMachine {
     return test;
   }
 
+  /* Need to use a function because @babel/plugin-proposal-class-properties */
+  static register_names() { 
+    return ['AX', 'BX', 'CX', 'DX'];
+  }
+
   static operations() {
     return Object.getOwnPropertyNames(ButtonMachine.prototype)
       .filter(x => x.startsWith('op_'))
@@ -137,11 +142,15 @@ class ButtonMachine {
   }
 
   op_STOR(reg) {
+    if(!this.assert(!reg.includes(reg), `Register ${reg} is not valid. Use ${ButtonMachine.registers_names()}`)) return;
+
     this.registers[reg] = this.stack_top;
     this.next();
   }
 
   op_RSTOR(reg) {
+    if(!this.assert(!reg.includes(reg), `Register ${reg} is not valid. Use ${ButtonMachine.registers_names()}`)) return;
+
     let val = this.registers[reg];
     this.assert(val !== undefined, `Invalid register ${reg}`);
 

src/routes/_layout.svelte

@@ -1,10 +1,15 @@
 <script>
   import Footer from '../components/Footer.svelte';
+  import Nav from '../components/Nav.svelte';
   import Sidebar from '../components/Sidebar.svelte';
+  export let segment;
 </script>
 
-<style>
+<style lang="scss">
-#main {
+
+  @import "sass/_variables";
+
+  #main {
     display: flex;
     flex: 1 0 auto;
     min-height: 100vh;
@@ -12,16 +17,18 @@
     padding-left: 0px;
     padding-right: 0px;
     min-width: 340px;
-}
+    border: 1px solid darken($green, 10%) !important;
+  }
 
-#main_content {
+  #main_content {
     flex-grow: 1;
-}
+  }
 </style>
 
-<div class="container grid-xl full-width" id="main">
+<div class="container grid-lg" id="main">
   <div class="columns" id="nav">
     <div class="column col-mx-auto">
+      <Nav {segment} />
     </div>
   </div>
 
@@ -29,15 +36,12 @@
     <div class="columns">
       <div class="column col-mx-auto">
         <div class="off-canvas">
-          <a class="off-canvas-toggle btn btn-primary btn-action" href="#sidebar-id">
-            ?¿
-          </a>
 
           <div id="sidebar-id" class="off-canvas-sidebar">
             <Sidebar />
           </div>
 
-          <a class="off-canvas-overlay" href="#close"></a>
+          <a alt="Close sidebar" aria-label="Close sidebar" class="off-canvas-overlay" href="#close">&nbsp;</a>
 
           <div class="off-canvas-content">
             <slot></slot>

src/routes/index.svelte

@@ -65,44 +65,38 @@
 <style lang="scss">
   @import "sass/_variables";
 
+  #status-panel {
+    font-size: 14px;
+  }
+
   .active-line {
-    background-color: $warning-color !important;
+    background-color: $green !important;
   }
 
   .empty-data {
     width: 100%;
     background-color: lighten($primary-color, 40%);
   }
+
+  .off-canvas-toggle {
+    position: unset;
+    z-index: unset;
+    top: unset;
+    left: unset;
+    display: unset;
+    transition: unset;
+    padding: 5px;
+  }
 </style>
 
-<div class="container grid-xl" id="content" data-testid="buttons-page">
+<div class="container grid-lg" id="content" data-testid="buttons-page">
   <div class="columns">
-    <div class="column col-12">
-      <table class="table">
-        <thead>
-          <tr>
-            <th>IP</th>
-            <th>TICK</th>
-            <th>HALT</th>
-            <th>ERROR</th>
-          </tr>
-        </thead>
-        <tbody>
-          <tr class="active">
-            <td>{ machine.ip }</td>
-            <td>{ machine.tick }</td>
-            <td>{ machine.halted }</td>
-            <td>{ machine.error }</td>
-          </tr>
-        </tbody>
-      </table>
-    </div>
-  </div>
 
-  <br/>
+    <div class="column col-4 col-sm-12 col-md-12 col-xs-12">
+      <a alt="Open/Close help sidebar" aria-label="Open/Close help sidebar" class="off-canvas-toggle btn btn-primary btn-action" href="#sidebar-id">
+        ?¿
+      </a>
 
-  <div class="columns">
-    <div class="column col-6">
       <button class="btn btn-primary" on:click={ run_machine }>
         <Icon code="►" tooltip="Run it" tooltip_right={ true } light={ true }/>
       </button>
@@ -115,7 +109,7 @@
 
       <div class="divider"></div>
       {#each code as [op, data], i} 
-        <div class="input-group" class:has-error={ has_error }>
+        <div class="input-group">
           {#if has_error && machine.error_line == i}
             <Icon name="alert-triangle" color="red" />
           {:else}
@@ -150,7 +144,26 @@
         </div>
       {/each}
     </div>
-    <div class="column col-2">
+
+    <div class="column col-8 col-sm-12 col-md-12 col-xs-12" id="status-panel">
+      <table class="table">
+        <thead>
+          <tr>
+            <th>IP</th>
+            <th>TICK</th>
+            <th>HALT</th>
+            <th>ERROR</th>
+          </tr>
+        </thead>
+        <tbody>
+          <tr class="active">
+            <td>{ machine.ip }</td>
+            <td>{ machine.tick }</td>
+            <td>{ machine.halted }</td>
+            <td>{ machine.error }</td>
+          </tr>
+        </tbody>
+      </table>
       <table class="table">      <thead>
           <tr>
             <th>STACK</th>
@@ -163,8 +176,7 @@
           </tr>
         {/each}
       </table>
-    </div>
+
-    <div class="column col-4">
       <table class="table">
         <thead>
           <tr>

src/service-worker.js

@@ -7,6 +7,8 @@ const ASSETS = `cache${timestamp}`;
 const to_cache = shell.concat(files);
 const cached = new Set(to_cache);
 
+self.skipWaiting();
+
 self.addEventListener('install', event => {
   event.waitUntil(
     caches
@@ -31,6 +33,8 @@ self.addEventListener('activate', event => {
   );
 });
 
+if(false) {
+
 self.addEventListener('fetch', event => {
   if (event.request.method !== 'GET' || event.request.headers.has('range')) return;
 
@@ -51,12 +55,10 @@ self.addEventListener('fetch', event => {
   // for pages, you might want to serve a shell `service-worker-index.html` file,
   // which Sapper has generated for you. It's not right for every
   // app, but if it's right for yours then uncomment this section
-  /*
   if (url.origin === self.origin && routes.find(route => route.pattern.test(url.pathname))) {
     event.respondWith(caches.match('/service-worker-index.html'));
     return;
   }
-  */
 
   if (event.request.cache === 'only-if-cached') return;
 
@@ -69,7 +71,7 @@ self.addEventListener('fetch', event => {
       .then(async cache => {
         try {
           const response = await fetch(event.request, {credentials: 'same-origin'});
-          // cache.put(event.request, response.clone());
+          cache.put(event.request, response.clone());
           return response;
         } catch(err) {
           const response = await cache.match(event.request);
@@ -80,3 +82,5 @@ self.addEventListener('fetch', event => {
       })
   );
 });
+
+}