enable redo support

Also:

- fix issues where the Undo action in the Browse screen was not
consistent with the main window. The existing hook signature has been
changed; from a snapshot of the add-on code from a few months ago, it
was not a hook that was being used by anyone.
- change the undo shortcut in the Browse window to match the main
window. It was different because undoing a change in the editing area
could accidentally trigger an undo of an operation, but the damage is
limited now that (most) operations can be redone. If it still proves to
be a problem, perhaps we should just always swallow ctrl+z when an
editing field is focused.

ftl/qt/qt-accel.ftl

@@ -30,5 +30,6 @@ qt-accel-support-anki = &Support Anki...
 qt-accel-switch-profile = &Switch Profile
 qt-accel-tools = &Tools
 qt-accel-undo = &Undo
+qt-accel-redo = &Redo
 qt-accel-set-due-date = Set &Due Date...
 qt-accel-forget = &Forget

pylib/anki/collection.py

@@ -885,7 +885,7 @@ table.review-log {{ {revlog_style} }}
     ##########################################################################
 
     def undo_status(self) -> UndoStatus:
-        "Return the undo status. At the moment, redo is not supported."
+        "Return the undo status."
         # check backend first
         if status := self._check_backend_undo_status():
             return status
@@ -939,6 +939,14 @@ table.review-log {{ {revlog_style} }}
             self.models._clear_cache()
         return out
 
+    def redo(self) -> OpChangesAfterUndo:
+        """Returns result of backend redo operation, or throws UndoEmpty."""
+        out = self._backend.redo()
+        self.clear_python_undo()
+        if out.changes.notetype:
+            self.models._clear_cache()
+        return out
+
     def undo_legacy(self) -> LegacyUndoResult:
         "Returns None if the legacy undo queue is empty."
         if isinstance(self._undo, _ReviewsUndo):

qt/aqt/browser/browser.py

@@ -19,7 +19,7 @@ from aqt import AnkiQt, gui_hooks
 from aqt.editor import Editor
 from aqt.exporting import ExportDialog
 from aqt.operations.card import set_card_deck, set_card_flag
-from aqt.operations.collection import undo
+from aqt.operations.collection import redo, undo
 from aqt.operations.note import remove_notes
 from aqt.operations.scheduling import (
     forget_cards,
@@ -35,6 +35,7 @@ from aqt.operations.tag import (
 )
 from aqt.qt import *
 from aqt.switch import Switch
+from aqt.undo import UndoActionsInfo
 from aqt.utils import (
     HelpPage,
     KeyboardModifiersPressed,
@@ -101,7 +102,8 @@ class Browser(QMainWindow):
         self.setupMenus()
         self.setupHooks()
         self.setupEditor()
-        self.onUndoState(self.mw.form.actionUndo.isEnabled())
+        # disable undo/redo
+        self.on_undo_state_change(mw.undo_actions_info())
         self.setupSearch(card, search)
         gui_hooks.browser_will_show(self)
         self.show()
@@ -139,6 +141,7 @@ class Browser(QMainWindow):
         f = self.form
         # edit
         qconnect(f.actionUndo.triggered, self.undo)
+        qconnect(f.actionRedo.triggered, self.redo)
         qconnect(f.actionInvertSelection.triggered, self.table.invert_selection)
         qconnect(f.actionSelectNotes.triggered, self.selectNotes)
         if not isMac:
@@ -786,14 +789,14 @@ where id in %s"""
     ######################################################################
 
     def setupHooks(self) -> None:
-        gui_hooks.undo_state_did_change.append(self.onUndoState)
+        gui_hooks.undo_state_did_change.append(self.on_undo_state_change)
         gui_hooks.backend_will_block.append(self.table.on_backend_will_block)
         gui_hooks.backend_did_block.append(self.table.on_backend_did_block)
         gui_hooks.operation_did_execute.append(self.on_operation_did_execute)
         gui_hooks.focus_did_change.append(self.on_focus_change)
 
     def teardownHooks(self) -> None:
-        gui_hooks.undo_state_did_change.remove(self.onUndoState)
+        gui_hooks.undo_state_did_change.remove(self.on_undo_state_change)
         gui_hooks.backend_will_block.remove(self.table.on_backend_will_block)
         gui_hooks.backend_did_block.remove(self.table.on_backend_will_block)
         gui_hooks.operation_did_execute.remove(self.on_operation_did_execute)
@@ -805,10 +808,15 @@ where id in %s"""
     def undo(self) -> None:
         undo(parent=self)
 
-    def onUndoState(self, on: bool) -> None:
+    def redo(self) -> None:
-        self.form.actionUndo.setEnabled(on)
+        redo(parent=self)
-        if on:
+
-            self.form.actionUndo.setText(self.mw.form.actionUndo.text())
+    def on_undo_state_change(self, info: UndoActionsInfo) -> None:
+        self.form.actionUndo.setText(info.undo_text)
+        self.form.actionUndo.setEnabled(info.can_undo)
+        self.form.actionRedo.setText(info.redo_text)
+        self.form.actionRedo.setEnabled(info.can_redo)
+        self.form.actionRedo.setVisible(info.show_redo)
 
     # Edit: replacing
     ######################################################################

qt/aqt/forms/browser.ui

@@ -144,12 +144,12 @@
           <attribute name="horizontalHeaderCascadingSectionResizes">
            <bool>false</bool>
           </attribute>
-          <attribute name="horizontalHeaderHighlightSections">
-           <bool>false</bool>
-          </attribute>
           <attribute name="horizontalHeaderMinimumSectionSize">
            <number>20</number>
           </attribute>
+          <attribute name="horizontalHeaderHighlightSections">
+           <bool>false</bool>
+          </attribute>
           <attribute name="horizontalHeaderShowSortIndicator" stdset="0">
            <bool>true</bool>
           </attribute>
@@ -209,7 +209,7 @@
      <x>0</x>
      <y>0</y>
      <width>750</width>
-     <height>21</height>
+     <height>24</height>
     </rect>
    </property>
    <widget class="QMenu" name="menuEdit">
@@ -217,6 +217,7 @@
      <string>qt_accel_edit</string>
     </property>
     <addaction name="actionUndo"/>
+    <addaction name="actionRedo"/>
     <addaction name="separator"/>
     <addaction name="action_toggle_mode"/>
     <addaction name="separator"/>
@@ -319,7 +320,7 @@
     <string>qt_accel_undo</string>
    </property>
    <property name="shortcut">
-    <string notr="true">Ctrl+Alt+Z</string>
+    <string notr="true">Ctrl+Z</string>
    </property>
   </action>
   <action name="actionInvertSelection">
@@ -613,6 +614,14 @@
     <string notr="true">Alt+T</string>
    </property>
   </action>
+  <action name="actionRedo">
+   <property name="text">
+    <string>qt_accel_redo</string>
+   </property>
+   <property name="shortcut">
+    <string notr="true">Ctrl+Shift+Z</string>
+   </property>
+  </action>
  </widget>
  <resources>
   <include location="icons.qrc"/>

qt/aqt/forms/main.ui

@@ -46,7 +46,7 @@
      <x>0</x>
      <y>0</y>
      <width>667</width>
-     <height>22</height>
+     <height>24</height>
     </rect>
    </property>
    <widget class="QMenu" name="menuHelp">
@@ -63,6 +63,7 @@
      <string>qt_accel_edit</string>
     </property>
     <addaction name="actionUndo"/>
+    <addaction name="actionRedo"/>
    </widget>
    <widget class="QMenu" name="menuCol">
     <property name="title">
@@ -237,6 +238,17 @@
     <string notr="true">Ctrl+Shift+A</string>
    </property>
   </action>
+  <action name="actionRedo">
+   <property name="enabled">
+    <bool>false</bool>
+   </property>
+   <property name="text">
+    <string>qt_accel_redo</string>
+   </property>
+   <property name="shortcut">
+    <string notr="true">Ctrl+Shift+Z</string>
+   </property>
+  </action>
  </widget>
  <resources>
   <include location="icons.qrc"/>

qt/aqt/main.py

@@ -53,7 +53,7 @@ from aqt.emptycards import show_empty_cards
 from aqt.legacy import install_pylib_legacy
 from aqt.mediacheck import check_media_db
 from aqt.mediasync import MediaSyncer
-from aqt.operations.collection import undo
+from aqt.operations.collection import redo, undo
 from aqt.operations.deck import set_current_deck
 from aqt.profiles import ProfileManager as ProfileManagerType
 from aqt.qt import *
@@ -61,6 +61,7 @@ from aqt.qt import sip
 from aqt.sync import sync_collection, sync_login
 from aqt.taskman import TaskManager
 from aqt.theme import theme_manager
+from aqt.undo import UndoActionsInfo
 from aqt.utils import (
     HelpPage,
     KeyboardModifiersPressed,
@@ -1070,44 +1071,31 @@ title="%s" %s>%s</button>""" % (
     ##########################################################################
 
     def undo(self) -> None:
-        "Call collection_ops.py:undo() directly instead."
+        "Call operations/collection.py:undo() directly instead."
         undo(parent=self)
 
-    def update_undo_actions(self, status: Optional[UndoStatus] = None) -> None:
+    def redo(self) -> None:
-        """Update menu text and enable/disable menu item as appropriate.
+        "Call operations/collection.py:redo() directly instead."
-        Plural as this may handle redo in the future too."""
+        redo(parent=self)
-        if self.col:
-            status = status or self.col.undo_status()
-            undo_action = status.undo or None
-        else:
-            undo_action = None
 
-        if undo_action:
+    def undo_actions_info(self) -> UndoActionsInfo:
-            undo_action = tr.undo_undo_action(val=undo_action)
+        "Info about the current undo/redo state for updating menus."
-            self.form.actionUndo.setText(undo_action)
+        status = self.col.undo_status() if self.col else UndoStatus()
-            self.form.actionUndo.setEnabled(True)
+        return UndoActionsInfo.from_undo_status(status)
-            gui_hooks.undo_state_did_change(True)
-        else:
-            self.form.actionUndo.setText(tr.undo_undo())
-            self.form.actionUndo.setEnabled(False)
-            gui_hooks.undo_state_did_change(False)
 
-    def _update_undo_actions_for_status_and_save(self, status: UndoStatus) -> None:
+    def update_undo_actions(self) -> None:
-        """Update menu text and enable/disable menu item as appropriate.
+        """Tell the UI to redraw the undo/redo menu actions based on the current state.
-        Plural as this may handle redo in the future too."""
-        undo_action = status.undo
 
-        if undo_action:
+        Usually you do not need to call this directly; it is called when a
-            undo_action = tr.undo_undo_action(val=undo_action)
+        CollectionOp is run, and will be called when the legacy .reset() or
-            self.form.actionUndo.setText(undo_action)
+        .checkpoint() methods are used."""
-            self.form.actionUndo.setEnabled(True)
+        info = self.undo_actions_info()
-            gui_hooks.undo_state_did_change(True)
+        self.form.actionUndo.setText(info.undo_text)
-        else:
+        self.form.actionUndo.setEnabled(info.can_undo)
-            self.form.actionUndo.setText(tr.undo_undo())
+        self.form.actionRedo.setText(info.redo_text)
-            self.form.actionUndo.setEnabled(False)
+        self.form.actionRedo.setEnabled(info.can_redo)
-            gui_hooks.undo_state_did_change(False)
+        self.form.actionRedo.setVisible(info.show_redo)
-
+        gui_hooks.undo_state_did_change(info)
-        self.col.autosave()
 
     def checkpoint(self, name: str) -> None:
         self.col.save(name)
@@ -1233,7 +1221,8 @@ title="%s" %s>%s</button>""" % (
         qconnect(m.actionExit.triggered, self.close)
         qconnect(m.actionPreferences.triggered, self.onPrefs)
         qconnect(m.actionAbout.triggered, self.onAbout)
-        qconnect(m.actionUndo.triggered, self.onUndo)
+        qconnect(m.actionUndo.triggered, self.undo)
+        qconnect(m.actionRedo.triggered, self.redo)
         if qtminor < 11:
             m.actionUndo.setShortcut(QKeySequence("Ctrl+Alt+Z"))
         qconnect(m.actionFullDatabaseCheck.triggered, self.onCheckDB)

qt/aqt/operations/__init__.py

@@ -111,9 +111,8 @@ class CollectionOp(Generic[ResultWithChanges]):
                 if self._success:
                     self._success(result)
             finally:
-                # update undo status
+                mw.update_undo_actions()
-                status = mw.col.undo_status()
+                mw.autosave()
-                mw._update_undo_actions_for_status_and_save(status)
                 # fire change hooks
                 self._fire_change_hooks_after_op_performed(result, initiator)
 

qt/aqt/operations/collection.py

@@ -32,6 +32,15 @@ def undo(*, parent: QWidget) -> None:
     ).run_in_background()
 
 
+def redo(*, parent: QWidget) -> None:
+    "Redo the last operation, and refresh the UI."
+
+    def on_success(out: OpChangesAfterUndo) -> None:
+        tooltip(tr.undo_action_redone(action=out.operation), parent=parent)
+
+    CollectionOp(parent, lambda col: col.redo()).success(on_success).run_in_background()
+
+
 def _legacy_undo(*, parent: QWidget) -> None:
     from aqt import mw
 

qt/aqt/undo.py

@@ -0,0 +1,36 @@
+# Copyright: Ankitects Pty Ltd and contributors
+# License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+
+from anki.collection import UndoStatus
+
+
+@dataclass
+class UndoActionsInfo:
+    can_undo: bool
+    can_redo: bool
+
+    undo_text: str
+    redo_text: str
+
+    # menu item is hidden when legacy undo is active, since it can't be undone
+    show_redo: bool
+
+    @staticmethod
+    def from_undo_status(status: UndoStatus) -> UndoActionsInfo:
+        from aqt import tr
+
+        return UndoActionsInfo(
+            can_undo=bool(status.undo),
+            can_redo=bool(status.redo),
+            undo_text=tr.undo_undo_action(val=status.undo)
+            if status.undo
+            else tr.undo_undo(),
+            redo_text=tr.undo_redo_action(action=status.undo)
+            if status.redo
+            else tr.undo_redo(),
+            show_redo=status.last_step > 0,
+        )

qt/tools/genhooks_gui.py

@@ -30,6 +30,7 @@ from anki.models import NotetypeDict
 from anki.collection import OpChangesAfterUndo
 from aqt.qt import QDialog, QEvent, QMenu, QWidget
 from aqt.tagedit import TagEdit
+from aqt.undo import UndoActionsInfo
 """
 
 # Hook list
@@ -675,9 +676,7 @@ gui_hooks.webview_did_inject_style_into_page.append(mytest)
         args=["col: anki.collection.Collection"],
         legacy_hook="colLoading",
     ),
-    Hook(
+    Hook(name="undo_state_did_change", args=["info: UndoActionsInfo"]),
-        name="undo_state_did_change", args=["can_undo: bool"], legacy_hook="undoState"
-    ),
     Hook(name="review_did_undo", args=["card_id: int"], legacy_hook="revertedCard"),
     Hook(
         name="style_did_init",