add a webview_did_receive_js_message hook

qt/aqt/browser.py

@@ -2133,7 +2133,7 @@ update cards set usn=?, mod=?, did=? where id in """
         frm.fields.addItems(fields)
         self._dupesButton = None
         # links
-        frm.webView.onBridgeCmd = self.dupeLinkClicked
+        frm.webView.set_bridge_command(self.dupeLinkClicked, "find_dupes")
 
         def onFin(code):
             saveGeom(d, "findDupes")

qt/aqt/clayout.py

@@ -216,6 +216,9 @@ class CardLayout(QDialog):
         pform.backWeb.stdHtml(
             self.mw.reviewer.revHtml(), css=["reviewer.css"], js=jsinc
         )
+        # specify a context for add-ons
+        pform.frontWeb.set_bridge_command(lambda msg: None, "card_layout")
+        pform.backWeb.set_bridge_command(lambda msg: None, "card_layout")
 
     def updateMainArea(self):
         if self._isCloze():

qt/aqt/deckbrowser.py

@@ -8,25 +8,25 @@ import aqt
 from anki.errors import DeckRenameError
 from anki.lang import _, ngettext
 from anki.utils import fmtTimeSpan, ids2str
-from aqt import gui_hooks
+from aqt import AnkiQt, gui_hooks
 from aqt.qt import *
 from aqt.sound import av_player
+from aqt.toolbar import BottomBar
 from aqt.utils import askUser, getOnlyText, openHelp, openLink, shortcut, showWarning
 
 
 class DeckBrowser:
     _dueTree: Any
 
-    def __init__(self, mw):
+    def __init__(self, mw: AnkiQt) -> None:
         self.mw = mw
         self.web = mw.web
-        self.bottom = aqt.toolbar.BottomBar(mw, mw.bottomWeb)
+        self.bottom = BottomBar(mw, mw.bottomWeb)
         self.scrollPos = QPoint(0, 0)
 
     def show(self):
         av_player.stop_and_clear_queue()
-        self.web.resetHandlers()
-        self.web.onBridgeCmd = self._linkHandler
+        self.web.set_bridge_command(self._linkHandler, "deck_browser")
         self._renderPage()
 
     def refresh(self):
@@ -330,7 +330,7 @@ where id > ?""",
                 b
             )
         self.bottom.draw(buf)
-        self.bottom.web.onBridgeCmd = self._linkHandler
+        self.bottom.web.set_bridge_command(self._linkHandler, "deck_browser_bottom_bar")
 
     def _onShared(self):
         openLink(aqt.appShared + "decks/")

qt/aqt/editor.py

@@ -96,7 +96,7 @@ class Editor:
         self.web = EditorWebView(self.widget, self)
         self.web.title = "editor"
         self.web.allowDrops = True
-        self.web.onBridgeCmd = self.onBridgeCmd
+        self.web.set_bridge_command(self.onBridgeCmd, "editor")
         self.outerLayout.addWidget(self.web, 1)
 
         righttopbtns: List[str] = [

qt/aqt/gui_hooks.py

@@ -913,6 +913,50 @@ class _UndoStateDidChangeHook:
 undo_state_did_change = _UndoStateDidChangeHook()
 
 
+class _WebviewDidReceiveJsMessageFilter:
+    """Used to handle pycmd() messages sent from Javascript.
+        
+        Message is the string passed to pycmd(). Context is what was
+        passed to set_bridge_command(), such as 'editor' or 'reviewer'.
+        
+        For messages you don't want to handle, return handled unchanged.
+        
+        If you handle a message and don't want it passed to the original
+        bridge command handler, return (True, None).
+          
+        If you want to pass a value to pycmd's result callback, you can
+        return it with (True, some_value)."""
+
+    _hooks: List[Callable[[Tuple[bool, Any], str, str], Tuple[bool, Any]]] = []
+
+    def append(
+        self, cb: Callable[[Tuple[bool, Any], str, str], Tuple[bool, Any]]
+    ) -> None:
+        """(handled: Tuple[bool, Any], message: str, context: str)"""
+        self._hooks.append(cb)
+
+    def remove(
+        self, cb: Callable[[Tuple[bool, Any], str, str], Tuple[bool, Any]]
+    ) -> None:
+        if cb in self._hooks:
+            self._hooks.remove(cb)
+
+    def __call__(
+        self, handled: Tuple[bool, Any], message: str, context: str
+    ) -> Tuple[bool, Any]:
+        for filter in self._hooks:
+            try:
+                handled = filter(handled, message, context)
+            except:
+                # if the hook fails, remove it
+                self._hooks.remove(filter)
+                raise
+        return handled
+
+
+webview_did_receive_js_message = _WebviewDidReceiveJsMessageFilter()
+
+
 class _WebviewWillShowContextMenuHook:
     _hooks: List[Callable[["aqt.webview.AnkiWebView", QMenu], None]] = []
 

qt/aqt/main.py

@@ -643,8 +643,9 @@ from the profile screen."
         if self.resetModal:
             # we don't have to change the webview, as we have a covering window
             return
-        self.web.resetHandlers()
-        self.web.onBridgeCmd = lambda url: self.delayedMaybeReset()
+        self.web.set_bridge_command(
+            lambda url: self.delayedMaybeReset(), "reset_required"
+        )
         i = _("Waiting for editing to finish.")
         b = self.button("refresh", _("Resume Now"), id="resume")
         self.web.stdHtml(

qt/aqt/overview.py

@@ -2,24 +2,26 @@
 # Copyright: Ankitects Pty Ltd and contributors
 # License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
+from __future__ import annotations
+
 import aqt
 from anki.lang import _
 from aqt.sound import av_player
+from aqt.toolbar import BottomBar
 from aqt.utils import askUserDialog, openLink, shortcut, tooltip
 
 
 class Overview:
     "Deck overview."
 
-    def __init__(self, mw):
+    def __init__(self, mw: aqt.AnkiQt) -> None:
         self.mw = mw
         self.web = mw.web
-        self.bottom = aqt.toolbar.BottomBar(mw, mw.bottomWeb)
+        self.bottom = BottomBar(mw, mw.bottomWeb)
 
     def show(self):
         av_player.stop_and_clear_queue()
-        self.web.resetHandlers()
-        self.web.onBridgeCmd = self._linkHandler
+        self.web.set_bridge_command(self._linkHandler, "overview")
         self.mw.setStateShortcuts(self._shortcutKeys())
         self.refresh()
 
@@ -235,7 +237,7 @@ to their original deck."""
                 b
             )
         self.bottom.draw(buf)
-        self.bottom.web.onBridgeCmd = self._linkHandler
+        self.bottom.web.set_bridge_command(self._linkHandler, "overview_bottom")
 
     # Studying more
     ######################################################################

qt/aqt/reviewer.py

@@ -10,7 +10,6 @@ import re
 import unicodedata as ucd
 from typing import List, Optional
 
-import aqt
 from anki import hooks
 from anki.cards import Card
 from anki.lang import _, ngettext
@@ -19,6 +18,7 @@ from anki.utils import bodyClass, stripHTML
 from aqt import AnkiQt, gui_hooks
 from aqt.qt import *
 from aqt.sound import av_player, getAudio
+from aqt.toolbar import BottomBar
 from aqt.utils import (
     askUserDialog,
     downArrow,
@@ -42,15 +42,14 @@ class Reviewer:
         self._current_side_audio: Optional[List[AVTag]] = None
         self.typeCorrect = None  # web init happens before this is set
         self.state: Optional[str] = None
-        self.bottom = aqt.toolbar.BottomBar(mw, mw.bottomWeb)
+        self.bottom = BottomBar(mw, mw.bottomWeb)
         hooks.card_did_leech.append(self.onLeech)
 
     def show(self):
         self.mw.col.reset()
-        self.web.resetHandlers()
         self.mw.setStateShortcuts(self._shortcutKeys())
-        self.web.onBridgeCmd = self._linkHandler
-        self.bottom.web.onBridgeCmd = self._linkHandler
+        self.web.set_bridge_command(self._linkHandler, "reviewer")
+        self.bottom.web.set_bridge_command(self._linkHandler, "reviewer_bottom")
         self._reps = None
         self.nextCard()
 

qt/aqt/toolbar.py

@@ -2,12 +2,16 @@
 # -*- coding: utf-8 -*-
 # License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
+from __future__ import annotations
+
+import aqt
 from anki.lang import _
 from aqt.qt import *
+from aqt.webview import AnkiWebView
 
 
 class Toolbar:
-    def __init__(self, mw, web):
+    def __init__(self, mw: aqt.AnkiQt, web: AnkiWebView) -> None:
         self.mw = mw
         self.web = web
         self.link_handlers = {
@@ -22,7 +26,7 @@ class Toolbar:
         self.web.requiresCol = False
 
     def draw(self):
-        self.web.onBridgeCmd = self._linkHandler
+        self.web.set_bridge_command(self._linkHandler, "top_toolbar")
         self.web.stdHtml(self._body % self._centerLinks(), css=["toolbar.css"])
         self.web.adjustHeightToFit()
 
@@ -107,7 +111,8 @@ class BottomBar(Toolbar):
 """
 
     def draw(self, buf):
-        self.web.onBridgeCmd = self._linkHandler
+        # note: some screens may override this
+        self.web.set_bridge_command(self._linkHandler, "bottom_toolbar")
         self.web.stdHtml(
             self._centerBody % buf, css=["toolbar.css", "toolbar-bottom.css"]
         )

qt/aqt/webview.py

@@ -4,6 +4,7 @@
 import json
 import math
 import sys
+from typing import Any, List, Optional, Tuple
 
 from anki.lang import _
 from anki.utils import isLin, isMac, isWin
@@ -99,18 +100,21 @@ class AnkiWebPage(QWebEnginePage):  # type: ignore
 
 
 class AnkiWebView(QWebEngineView):  # type: ignore
-    def __init__(self, parent=None):
-        QWebEngineView.__init__(self, parent=parent)
+    def __init__(self, parent: Optional[QWidget] = None) -> None:
+        QWebEngineView.__init__(self, parent=parent)  # type: ignore
         self.title = "default"
         self._page = AnkiWebPage(self._onBridgeCmd)
         self._page.setBackgroundColor(self._getWindowColor())  # reduce flicker
 
+        # in new code, use .set_bridge_command() instead of setting this directly
+        self.onBridgeCmd: Callable[[str], Any] = self.defaultOnBridgeCmd
+
         self._domDone = True
-        self._pendingActions = []
+        self._pendingActions: List[Tuple[str, List[Any]]] = []
         self.requiresCol = True
         self.setPage(self._page)
 
-        self._page.profile().setHttpCacheType(QWebEngineProfile.NoCache)
+        self._page.profile().setHttpCacheType(QWebEngineProfile.NoCache)  # type: ignore
         self.resetHandlers()
         self.allowDrops = False
         self._filterSet = False
@@ -119,7 +123,7 @@ class AnkiWebView(QWebEngineView):  # type: ignore
             self,
             context=Qt.WidgetWithChildrenShortcut,
             activated=self.onEsc,
-        )
+        )  # type: ignore
         if isMac:
             for key, fn in [
                 (QKeySequence.Copy, self.onCopy),
@@ -129,13 +133,13 @@ class AnkiWebView(QWebEngineView):  # type: ignore
             ]:
                 QShortcut(
                     key, self, context=Qt.WidgetWithChildrenShortcut, activated=fn
-                )
+                )  # type: ignore
             QShortcut(
                 QKeySequence("ctrl+shift+v"),
                 self,
                 context=Qt.WidgetWithChildrenShortcut,
                 activated=self.onPaste,
-            )
+            )  # type: ignore
 
     def eventFilter(self, obj, evt):
         # disable pinch to zoom gesture
@@ -391,7 +395,7 @@ body {{ zoom: {}; background: {}; {} }}
             return True
         return False
 
-    def _onBridgeCmd(self, cmd):
+    def _onBridgeCmd(self, cmd: str) -> Any:
         if self._shouldIgnoreWebEvent():
             print("ignored late bridge cmd", cmd)
             return
@@ -404,13 +408,21 @@ body {{ zoom: {}; background: {}; {} }}
             self._domDone = True
             self._maybeRunActions()
         else:
-            return self.onBridgeCmd(cmd)
+            handled, result = gui_hooks.webview_did_receive_js_message(
+                (False, None), cmd, self._bridge_command_name
+            )
+            if handled:
+                return result
+            else:
+                return self.onBridgeCmd(cmd)
 
-    def defaultOnBridgeCmd(self, cmd):
+    def defaultOnBridgeCmd(self, cmd: str) -> Any:
         print("unhandled bridge cmd:", cmd)
 
+    # legacy
     def resetHandlers(self):
         self.onBridgeCmd = self.defaultOnBridgeCmd
+        self._bridge_command_name = "unknown"
 
     def adjustHeightToFit(self):
         self.evalWithCallback("$(document.body).height()", self._onHeight)
@@ -429,3 +441,11 @@ body {{ zoom: {}; background: {}; {} }}
 
         height = math.ceil(qvar * scaleFactor)
         self.setFixedHeight(height)
+
+    def set_bridge_command(self, func: Callable[[str], Any], context: str) -> None:
+        """Set a handler for pycmd() messages received from Javascript.
+
+        Context is a human readable name that is provided to the
+        webview_did_receive_js_message hook."""
+        self.onBridgeCmd = func
+        self._bridge_command_name = context

qt/tools/genhooks_gui.py

@@ -65,11 +65,6 @@ hooks = [
         args=["browser: aqt.browser.Browser"],
         legacy_hook="browser.rowChanged",
     ),
-    Hook(
-        name="webview_will_show_context_menu",
-        args=["webview: aqt.webview.AnkiWebView", "menu: QMenu"],
-        legacy_hook="AnkiWebView.contextMenuEvent",
-    ),
     # States
     ###################
     Hook(
@@ -98,6 +93,30 @@ hooks = [
         legacy_hook="reset",
         doc="Called when the interface needs to be redisplayed after non-trivial changes have been made.",
     ),
+    # Webview
+    ###################
+    Hook(
+        name="webview_did_receive_js_message",
+        args=["handled: Tuple[bool, Any]", "message: str", "context: str"],
+        return_type="Tuple[bool, Any]",
+        doc="""Used to handle pycmd() messages sent from Javascript.
+        
+        Message is the string passed to pycmd(). Context is what was
+        passed to set_bridge_command(), such as 'editor' or 'reviewer'.
+        
+        For messages you don't want to handle, return handled unchanged.
+        
+        If you handle a message and don't want it passed to the original
+        bridge command handler, return (True, None).
+          
+        If you want to pass a value to pycmd's result callback, you can
+        return it with (True, some_value).""",
+    ),
+    Hook(
+        name="webview_will_show_context_menu",
+        args=["webview: aqt.webview.AnkiWebView", "menu: QMenu"],
+        legacy_hook="AnkiWebView.contextMenuEvent",
+    ),
     # Main
     ###################
     Hook(name="profile_did_open", legacy_hook="profileLoaded"),