From c9b0c23aeb635ce1c45120f187711508f2f9a9d7 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 16 Feb 2023 13:42:16 +0530
Subject: [PATCH] Respond to wheel event in the image popup

---
 src/pyj/image_popup.pyj | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/pyj/image_popup.pyj b/src/pyj/image_popup.pyj
index 9ec425fd47..502b4190fd 100644
--- a/src/pyj/image_popup.pyj
+++ b/src/pyj/image_popup.pyj
@@ -67,6 +67,7 @@ class ImagePopup(TouchHandler):
                 style=f'display:none; position:absolute; left:0; top: 0; z-index: {MODAL_Z_INDEX}; width: 100vw; height: 100vh; padding: 0; margin: 0; border-width: 0; box-sizing: border-box',
                 id=self.container_id, tabindex='0', class_='calibre-image-popup',
                 onkeydown=self.onkeydown,
+                onwheel=self.onwheel,
                 E.div(
                     style='position: fixed; top: 0; left: 0; text-align: right; width: 100%; font-size: 200%; padding: 0.25ex; box-sizing: border-box; display: flex; justify-content: space-between',
                     E.a(
@@ -89,6 +90,16 @@ class ImagePopup(TouchHandler):
             window.addEventListener('resize', debounce(self.resize_canvas, 250))
         return self._container
 
+    def onwheel(self, ev):
+        ev.stopPropagation(), ev.preventDefault()
+        dy = ev.deltaY
+        dx = ev.deltaX
+        if ev.deltaMode is window.WheelEvent.DOM_DELTA_LINE:
+            dy *= 20
+            dx *= 20
+        self.scroll_y(dy)
+        self.scroll_x(dx)
+
     def onkeydown(self, ev):
         ev.preventDefault(), ev.stopPropagation()
         if ev.key is ' ':
@@ -285,6 +296,7 @@ class ImagePopup(TouchHandler):
 
     def toggle_fit_to_window(self):
         self.fit_to_window ^= True
+        self.x = self.y = 0
         self.update_canvas()
 
     def image_loaded(self):