Use the built-in keyboard commands system

Registration and conflict resolution is simplified. Change default to
one that's unused by Firefox itself. Simplifies code but requires an
extra permission to find current tab.

Author: Roy-Orbison

webex/background.js

@@ -19,7 +19,7 @@ function assertNoResponse(response) {
 }
 
 function notifyError(error) {
-    browser.notifications.create({
+    browser.notifications?.create({
         type: "basic",
         title: "Textern",
         message: "Error: " + error + "."
@@ -126,3 +126,16 @@ function onMessage(message, sender, respond) {
 }
 
 browser.runtime.onMessage.addListener(onMessage);
+
+browser.commands.onCommand.addListener(function(command) {
+    if (command === 'textern') {
+        browser.tabs.query({
+            currentWindow: true,
+            active: true
+        }).then(function(tabs) {
+            if (tabs?.length && tabs[0].id != browser.tabs.TAB_ID_NONE) {
+                browser.tabs.sendMessage(tabs[0].id, {type: 'shortcut'}).then(assertNoResponse, logError);
+            }
+        });
+    }
+});

webex/content.js

@@ -17,7 +17,7 @@ function assertNoResponse(response) {
 }
 
 function notifyError(error) {
-    browser.notifications.create({
+    browser.notifications?.create({
         type: "basic",
         title: "Textern",
         message: "Error: " + error + "."
@@ -91,8 +91,7 @@ function slackSetText(e, text) {
     }
 }
 
-function registerText(event) {
-    var e = event.target;
+function registerText(e) {
     if (e.nodeName == "TEXTAREA") {
         var id = watchElement(e);
         /* don't use href directly to not bring in e.g. url params */
@@ -171,43 +170,37 @@ function setText(id, text) {
     fadeBackground(e);
 }
 
+function getActiveElement(element = document.activeElement) {
+    if (element.nodeName === 'IFRAME' || element.nodeName === 'FRAME')
+        return null; // skip to allow child documents to handle shortcut
+
+    const shadowRoot = element.shadowRoot
+    const contentDocument = element.contentDocument
+
+    if (shadowRoot && shadowRoot.activeElement) {
+        return getActiveElement(shadowRoot.activeElement)
+    }
+
+    if (contentDocument && contentDocument.activeElement) {
+        return getActiveElement(contentDocument.activeElement)
+    }
+
+    return element
+}
+
 function onMessage(message, sender, respond) {
     if (sender.id != "[email protected]")
         return;
-    if (message.type == "set_text")
+    if (message.type == 'shortcut') {
+        const activeElement = getActiveElement();
+        if (activeElement)
+            registerText(activeElement);
+    }
+    else if (message.type == "set_text")
         setText(message.id, message.text);
     else {
         console.log(`Unknown message type: ${message.type}`);
     }
 }
 
 browser.runtime.onMessage.addListener(onMessage);
-
-var currentShortcut = undefined;
-function registerShortcut(force) {
-    browser.storage.local.get({shortcut: "Ctrl+Shift+D"}).then(val => {
-        if ((val.shortcut == currentShortcut) && !force)
-            return; /* no change */
-        if (currentShortcut != undefined)
-            shortcut.remove(currentShortcut);
-        currentShortcut = val.shortcut;
-        shortcut.add(currentShortcut, registerText);
-    });
-}
-
-registerShortcut(true);
-
-/* meh, we just re-apply the shortcut -- XXX: should check what actually changed */
-browser.storage.onChanged.addListener(function(changes, areaName) {
-    registerShortcut(false);
-});
-
-/* we also want to make sure we re-register whenever the number of iframes changes */
-var lastNumFrames = window.frames.length;
-const observer = new MutationObserver(function() {
-    if (window.frames.length != lastNumFrames) {
-        registerShortcut(true);
-        lastNumFrames = window.frames.length;
-    }
-});
-observer.observe(document, {childList: true, subtree: true});

webex/manifest.json

@@ -3,7 +3,7 @@
   "description": "Edit text in your favourite external editor!",
   "homepage_url": "https://github.com/jlebon/textern",
   "manifest_version": 2,
-  "version": "0.8",
+  "version": "0.9b1",
 
   "browser_specific_settings": {
     "gecko": {
@@ -17,15 +17,32 @@
   },
 
   "content_scripts": [
-      {
-          "matches": ["<all_urls>"],
-          "js": ["shortcut.js", "content.js"]
-      }
+    {
+      "matches": ["<all_urls>"],
+      "js": [
+        "content.js"
+      ],
+      "all_frames": true
+    }
   ],
 
+  "commands": {
+    "textern": {
+      "suggested_key": {
+        "default": "Shift+Alt+D"
+      },
+      "description": "Edit externally"
+    }
+  },
+
   "options_ui": {
       "page": "options.html"
   },
 
-  "permissions": ["notifications", "nativeMessaging", "storage"]
+  "permissions": [
+    "tabs",
+    "notifications",
+    "nativeMessaging",
+    "storage"
+  ]
 }

webex/options.html

@@ -13,15 +13,14 @@
       <input type="text" id="editor" required=true
              pattern='\[ *"[^"]*"(, *"[^"]*")* *\]'
              title='Must be in the form: ["executable", "arg", "arg", ...]'>
-      <label for="shortcut">Shortcut</label>
-      <input type="text" id="shortcut" required=true>
       <label for="extension">Document extension</label>
       <input type="text" id="extension" required=true pattern="[.a-zA-Z0-9_-]+"
              title='Must be an alphanumerical string (excluding leading dot)'>
       <label for="backupdir">Backup files to directory (experimental)</label>
       <input type="text" id="backupdir">
       <button type="submit">Save</button><span id="saved"></span>
     </form>
+    <p>Shortcut can be configured on the Manage Extension Shortcuts settings page.</p>
     <script src="options.js" charset="utf-8"></script>
   </body>
 </html>

webex/options.js

@@ -14,7 +14,6 @@ function saveOptions(e) {
     e.preventDefault();
     browser.storage.local.set({
         editor: document.querySelector("#editor").value,
-        shortcut: document.querySelector("#shortcut").value,
         extension: document.querySelector("#extension").value,
         backupdir: document.querySelector("#backupdir").value
     });
@@ -32,10 +31,6 @@ function restoreOptions() {
             result.editor || "[\"gedit\", \"+%l:%c\"]";
     }, onError);
 
-    browser.storage.local.get("shortcut").then(result => {
-        document.querySelector("#shortcut").value = result.shortcut || "Ctrl+Shift+D";
-    }, onError);
-
     browser.storage.local.get("extension").then(result => {
         document.querySelector("#extension").value = result.extension || "txt";
     }, onError);