1 files changed, 32 insertions, 1 deletions

diff --git a/ext/fg/js/popup-proxy-host.js b/ext/fg/js/popup-proxy-host.js
index 4dc79943..487dda90 100644
--- a/ext/fg/js/popup-proxy-host.js
+++ b/ext/fg/js/popup-proxy-host.js
@@ -19,6 +19,7 @@
 /* global
  * FrontendApiReceiver
  * Popup
+ * apiForward
  * apiFrameInformationGet
  */
 
@@ -48,6 +49,12 @@ class PopupProxyHost {
             ['clearAutoPlayTimer', this._onApiClearAutoPlayTimer.bind(this)],
             ['setContentScale', this._onApiSetContentScale.bind(this)]
         ]));
+
+        this._windowMessageHandlers = new Map([
+            ['getIframeOffset', ({offset, uniqueId}, e) => { return this._onGetIframeOffset(offset, uniqueId, e); }]
+        ]);
+
+        window.addEventListener('message', this.onMessage.bind(this), false);
     }
 
     getOrCreatePopup(id=null, parentId=null, depth=null) {
@@ -95,7 +102,7 @@ class PopupProxyHost {
         return popup;
     }
 
-    // Message handlers
+    // API message handlers
 
     async _onApiGetOrCreatePopup({id, parentId}) {
         const popup = this.getOrCreatePopup(id, parentId);
@@ -152,6 +159,30 @@ class PopupProxyHost {
         return popup.setContentScale(scale);
     }
 
+    // Window message handlers
+
+    onMessage(e) {
+        const {action, params} = e.data;
+        const handler = this._windowMessageHandlers.get(action);
+        if (typeof handler !== 'function') { return; }
+        handler(params, e);
+    }
+
+    _onGetIframeOffset(offset, uniqueId, e) {
+        let sourceIframe = null;
+        for (const iframe of document.querySelectorAll('iframe:not(.yomichan-float)')) {
+            if (iframe.contentWindow !== e.source) { continue; }
+            sourceIframe = iframe;
+            break;
+        }
+        if (sourceIframe === null) { return; }
+
+        const [forwardedX, forwardedY] = offset;
+        const {x, y} = sourceIframe.getBoundingClientRect();
+        offset = [forwardedX + x, forwardedY + y];
+        apiForward('iframeOffset', {offset, uniqueId});
+    }
+
     // Private functions
 
     _getPopup(id) {