1 files changed, 78 insertions, 0 deletions
diff --git a/browser/extensions/pocket/content/panels/js/messages.js b/browser/extensions/pocket/content/panels/js/messages.js
new file mode 100644
index 000000000..ae08c3e73
--- /dev/null
+++ b/browser/extensions/pocket/content/panels/js/messages.js
@@ -0,0 +1,78 @@
+// Documentation of methods used here are at:
+// https://developer.mozilla.org/en-US/Add-ons/Code_snippets/Interaction_between_privileged_and_non-privileged_pages
+
+var pktPanelMessaging = (function() {
+
+ function panelIdFromURL(url) {
+   var panelId = url.match(/panelId=([\w|\d|\.]*)&?/);
+        if (panelId && panelId.length > 1) {
+            return panelId[1];
+        }
+
+        return 0;
+ }
+
+ function prefixedMessageId(messageId) {
+   return 'PKT_' + messageId;
+ }
+
+ function panelPrefixedMessageId(panelId, messageId) {
+   return prefixedMessageId(panelId + '_' + messageId);
+ }
+
+ function addMessageListener(panelId, messageId, callback) {
+   document.addEventListener(panelPrefixedMessageId(panelId, messageId), function(e) {
+
+			callback(JSON.parse(e.target.getAttribute("payload"))[0]);
+
+			// TODO: Figure out why e.target.parentNode is null
+			// e.target.parentNode.removeChild(e.target);
+
+		}, false);
+
+	}
+
+	function removeMessageListener(panelId, messageId, callback) {
+   document.removeEventListener(panelPrefixedMessageId(panelId, messageId), callback);
+	}
+
+ function sendMessage(panelId, messageId, payload, callback) {
+   // Payload needs to be an object in format:
+   // { panelId: panelId, data: {} }
+   var messagePayload = {
+     panelId: panelId,
+     data: (payload || {})
+   };
+
+		// Create a callback to listen for a response
+		if (callback) {
+	        var messageResponseId = messageId + "Response";
+	        var responseListener = function(responsePayload) {
+	            callback(responsePayload);
+	            removeMessageListener(panelId, messageResponseId, responseListener);
+	        }
+
+	        addMessageListener(panelId, messageResponseId, responseListener);
+	    }
+
+	    // Send message
+		var element = document.createElement("PKTMessageFromPanelElement");
+		element.setAttribute("payload", JSON.stringify([messagePayload]));
+		document.documentElement.appendChild(element);
+
+		var evt = document.createEvent("Events");
+		evt.initEvent(prefixedMessageId(messageId), true, false);
+		element.dispatchEvent(evt);
+	}
+
+
+    /**
+     * Public functions
+     */
+    return {
+      panelIdFromURL: panelIdFromURL,
+        addMessageListener : addMessageListener,
+        removeMessageListener : removeMessageListener,
+        sendMessage: sendMessage
+    };
+}());