From 254dd6243bcaf76697aade1285423a31605e0e72 Mon Sep 17 00:00:00 2001
From: Paulus Schoutsen <paulus@paulusschoutsen.nl>
Date: Mon, 7 Dec 2015 23:06:58 -0800
Subject: [PATCH] Cache index in service worker

---
 src/service-worker/index.js | 38 +++++++++++++++++++++++++++++++++++--
 1 file changed, 36 insertions(+), 2 deletions(-)

diff --git a/src/service-worker/index.js b/src/service-worker/index.js
index 40e94ec79c..474809fd6f 100644
--- a/src/service-worker/index.js
+++ b/src/service-worker/index.js
@@ -1,3 +1,8 @@
+const CACHE = '0.10';
+const INDEX_CACHE_URL = '/';
+const INDEX_ROUTES = ['/', '/logbook', '/history', '/map', '/devService', '/devState',
+                      '/devEvent', '/devInfo', '/states'];
+
 if (__DEV__) {
   console.log('Service Worker initialized.');
 }
@@ -6,6 +11,10 @@ self.addEventListener('install', event => {
   if (__DEV__) {
     console.log('Service Worker installed.');
   }
+
+  event.waitUntil(
+    caches.open(CACHE).then(cache => cache.add(INDEX_CACHE_URL))
+  );
 });
 
 self.addEventListener('activate', event => {
@@ -16,8 +25,33 @@ self.addEventListener('activate', event => {
   }
 });
 
-self.addEventListener('onmessage', message => {
+self.addEventListener('message', event => {
   if (__DEV__) {
-    console.log('Message received', message);
+    console.log('Message received', event.data);
   }
 });
+
+self.addEventListener('fetch', event => {
+  const path = event.request.url.substr(event.request.url.indexOf('/', 7));
+
+  if (event.request.mode !== 'same-origin' || !INDEX_ROUTES.includes(path)) {
+    return fetch(event.request);
+  }
+
+  event.respondWith(
+    caches.open(CACHE).then(cache => {
+      return cache.match(INDEX_CACHE_URL).then(cachedResponse => {
+        const networkFetch = fetch(event.request).then(response => {
+          cache.put(INDEX_CACHE_URL, response.clone());
+          return response;
+        });
+
+        if (__DEV__ && cachedResponse) {
+          console.log('Serving cached response for', path);
+        }
+
+        return cachedResponse || networkFetch;
+      });
+    })
+  );
+});