From b966cdcef763b389968682bd7ead7bc49445e4c0 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Wed, 1 Jan 2020 10:08:50 +0530
Subject: [PATCH] Viewer: Allow right clicking in the lookup panel to zoom
 in/out. Fixes #1857989 [Increase font size of "Lookup" pop-up
 [enhancement]](https://bugs.launchpad.net/calibre/+bug/1857989)

---
 src/calibre/gui2/viewer/lookup.py   | 25 +++++++++++++++++++++++--
 src/calibre/gui2/viewer/web_view.py |  2 +-
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/src/calibre/gui2/viewer/lookup.py b/src/calibre/gui2/viewer/lookup.py
index 296d07789c..9abdd6c256 100644
--- a/src/calibre/gui2/viewer/lookup.py
+++ b/src/calibre/gui2/viewer/lookup.py
@@ -20,7 +20,7 @@ from PyQt5.QtWebEngineWidgets import (
 from calibre import prints, random_user_agent
 from calibre.constants import cache_dir
 from calibre.gui2 import error_dialog
-from calibre.gui2.viewer.web_view import vprefs
+from calibre.gui2.viewer.web_view import apply_font_settings, vprefs
 from calibre.gui2.webengine import create_script, insert_scripts, secure_webengine
 from calibre.gui2.widgets2 import Dialog
 
@@ -209,6 +209,26 @@ class Page(QWebEnginePage):
             prints('%s: %s:%s: %s' % (prefix, source_id, linenumber, msg), file=sys.stderr)
             sys.stderr.flush()
 
+    def zoom_in(self):
+        self.setZoomFactor(min(self.zoomFactor() + 0.25, 5))
+
+    def zoom_out(self):
+        self.setZoomFactor(max(0.25, self.zoomFactor() - 0.25))
+
+    def default_zoom(self):
+        self.setZoomFactor(1)
+
+
+class View(QWebEngineView):
+
+    def contextMenuEvent(self, ev):
+        menu = self.page().createStandardContextMenu()
+        menu.addSeparator()
+        menu.addAction(_('Zoom in'), self.page().zoom_in)
+        menu.addAction(_('Zoom out'), self.page().zoom_out)
+        menu.addAction(_('Default zoom'), self.page().default_zoom)
+        menu.exec_(ev.globalPos())
+
 
 class Lookup(QWidget):
 
@@ -226,8 +246,9 @@ class Lookup(QWidget):
         self.source_box = sb = QComboBox(self)
         self.label = la = QLabel(_('Lookup &in:'))
         h.addWidget(la), h.addWidget(sb), la.setBuddy(sb)
-        self.view = QWebEngineView(self)
+        self.view = View(self)
         self._page = Page(create_profile(), self.view)
+        apply_font_settings(self._page)
         secure_webengine(self._page, for_viewer=True)
         self.view.setPage(self._page)
         l.addWidget(self.view)
diff --git a/src/calibre/gui2/viewer/web_view.py b/src/calibre/gui2/viewer/web_view.py
index 1d351ef6ec..66ec449a6c 100644
--- a/src/calibre/gui2/viewer/web_view.py
+++ b/src/calibre/gui2/viewer/web_view.py
@@ -504,7 +504,7 @@ class WebView(RestartingWebEngineView):
         # TODO: Add UI for this
         ss = vprefs['session_data'].get('zoom_step_size') or 20
         amt = (ss / 100) * steps
-        self._page.setZoomFactor(self._page.zoomFactor() + amt)
+        self._page.setZoomFactor(max(0.25, min(self._page.zoomFactor() + amt, 5)))
 
     def render_process_died(self):
         if self.dead_renderer_error_shown: