1 files changed, 58 insertions, 0 deletions
diff --git a/toolkit/jetpack/sdk/keyboard/observer.js b/toolkit/jetpack/sdk/keyboard/observer.js
new file mode 100644
index 000000000..b8e32b95c
--- /dev/null
+++ b/toolkit/jetpack/sdk/keyboard/observer.js
@@ -0,0 +1,58 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+module.metadata = {
+  "stability": "unstable"
+};
+
+const { Class } = require("../core/heritage");
+const { EventTarget } = require("../event/target");
+const { emit } = require("../event/core");
+const { DOMEventAssembler } = require("../deprecated/events/assembler");
+const { browserWindowIterator } = require('../deprecated/window-utils');
+const { isBrowser } = require('../window/utils');
+const { observer: windowObserver } = require("../windows/observer");
+
+// Event emitter objects used to register listeners and emit events on them
+// when they occur.
+const Observer = Class({
+  implements: [DOMEventAssembler, EventTarget],
+  initialize() {
+    // Adding each opened window to a list of observed windows.
+    windowObserver.on("open", window => {
+      if (isBrowser(window))
+        this.observe(window);
+    });
+
+    // Removing each closed window form the list of observed windows.
+    windowObserver.on("close", window => {
+      if (isBrowser(window))
+        this.ignore(window);
+    });
+
+    // Making observer aware of already opened windows.
+    for (let window of browserWindowIterator()) {
+      this.observe(window);
+    }
+  },
+  /**
+   * Events that are supported and emitted by the module.
+   */
+  supportedEventsTypes: [ "keydown", "keyup", "keypress" ],
+  /**
+   * Function handles all the supported events on all the windows that are
+   * observed. Method is used to proxy events to the listeners registered on
+   * this event emitter.
+   * @param {Event} event
+   *    Keyboard event being emitted.
+   */
+  handleEvent(event) {
+    emit(this, event.type, event, event.target.ownerDocument ? event.target.ownerDocument.defaultView
+                                                             : undefined);
+  }
+});
+
+exports.observer = new Observer();