Fix: better handling of multi-window and idle background script

- Previously when the background script became idle, the stumbleTabId was lost, causing a new tab to open.
- When extension is ran in another window, tab opens in the new window

CHANGELOG.md

@@ -3,6 +3,9 @@ Check out past and upcoming releases here!
 
 ## [Unreleased]
 
+### Fixed
+- Bug with idle extension causing stumble page to open in new tab instead of existing.
+
 ## [1.0.5] - 29 Feb 2020
 ### Added
 - Additional info bubble on every stumble showing the site and source awesome-list

extension/background.js

@@ -4,6 +4,12 @@
  * Keep track of the StumbleUponAwesome tab
  */
 var stumbleTabId = null;
+
+/**
+ * The focused window ID
+ */
+var windowId = null;
+
 var totalUrls = 0; // to be counted on first run
 var os = 'mac'; // mac", "win", "android", "cros", "linux"
 
@@ -65,17 +71,17 @@ function loadUrl() {
         } catch (exception) {
           chrome.tabs.update({
             url: stumbleUrl.url,
-          }, function (tab) {
-            stumbleTabId = tab.id
+          }, async function (tab) {
+            await saveStumbleTabId(tab.id);
           })
         }
       }
       // or Open New tab
       else {
         chrome.tabs.create({
           url: stumbleUrl.url,
-        }, function (tab) {
-          stumbleTabId = tab.id
+        }, async function (tab) {
+          await saveStumbleTabId(tab.id);
         })
       }
     }
@@ -217,8 +223,26 @@ async function animateIcon() {
   });
 }
 
-function resetIcon() {
+const saveStumbleTabId = tabId => {
+  return new Promise((resolve, reject) => {
+    chrome.storage.local.set({ 'stumbleTabId': tabId }, function () {
+      console.log(`Saved stumble tabId: ${tabId}`);
+      stumbleTabId = tabId;
+      resolve();
+    });
+  })
+}
 
+const getStumbleTabId = () => {
+  return new Promise((resolve, reject) => {
+    chrome.storage.local.get(['stumbleTabId'], function (result) {
+      if (result.stumbleTabId) {
+        resolve(result.stumbleTabId);
+      } else {
+        resolve(null);
+      }
+    })
+  });
 }
 
 function update() {
@@ -272,7 +296,23 @@ function notifyTabWelcome() {
 
 // Load a page on click
 chrome.browserAction.onClicked.addListener(
-  function (tab) {
+  async function (tab) {
+
+    const currentWindowId = await getFocusedWindowId();
+    console.log(`oldWindow: ${windowId} newWindow: ${currentWindowId}`)
+    // Get stumble tab Id
+    const savedStumbleTabId = await getStumbleTabId();
+    const tabs = await getBrowserTabs();
+    const tabIds = tabs.map(t=>t.id);
+
+    // Reset if necessary
+    if (windowId !== currentWindowId || !stumbleTabId || !tabIds.includes(savedStumbleTabId)) {
+      windowId = currentWindowId;
+      chrome.storage.local.remove(['stumbleTabId'], () => {
+        stumbleTabId = null;
+      })
+    }
+
     isPendingStumble = true;
     loadUrl();
     animateIcon();
@@ -303,6 +343,30 @@ chrome.runtime.onInstalled.addListener(function () {
   })
 });
 
+/**
+ * Return the list of Chrome tabs
+ * @returns {Promise<Array<chrome.tabs.Tab>>}
+ */
+const getBrowserTabs = async () => {
+  return new Promise((resolve, reject) => {
+    chrome.tabs.query({currentWindow: true}, function (tabs) {
+      resolve(tabs);
+    });
+  })
+}
+
+/**
+ * Return the recently focused window id.
+ * @returns {Promise<number>}
+ */
+const getFocusedWindowId = () => {
+  return new Promise((resolve, reject) => {
+    chrome.windows.getCurrent(window => {
+      resolve(window.id);
+    });
+  });
+}
+
 /*
 Context menu
 */