Merge pull request #735 from brownbat/master

Add hook for initializing answer buttons

qt/aqt/gui_hooks.py

@@ -2213,6 +2213,69 @@ class _ReviewerWillEndHook:
 reviewer_will_end = _ReviewerWillEndHook()
 
 
+class _ReviewerWillInitAnswerButtonsFilter:
+    """Used to modify list of answer buttons
+
+        buttons_tuple is a tuple of buttons, with each button represented by a 
+        tuple containing an int for the button's ease and a string for the 
+        button's label.
+
+        Return a tuple of the form ((int, str), ...), e.g.:
+            ((1, "Label1"), (2, "Label2"), ...)
+
+        Note: import _ from anki.lang to support translation, using, e.g.,
+            ((1, _("Label1")), ...)
+        """
+
+    _hooks: List[
+        Callable[
+            ["Tuple[Tuple[int, str], ...]", "aqt.reviewer.Reviewer", Card],
+            Tuple[Tuple[int, str], ...],
+        ]
+    ] = []
+
+    def append(
+        self,
+        cb: Callable[
+            ["Tuple[Tuple[int, str], ...]", "aqt.reviewer.Reviewer", Card],
+            Tuple[Tuple[int, str], ...],
+        ],
+    ) -> None:
+        """(buttons_tuple: Tuple[Tuple[int, str], ...], reviewer: aqt.reviewer.Reviewer, card: Card)"""
+        self._hooks.append(cb)
+
+    def remove(
+        self,
+        cb: Callable[
+            ["Tuple[Tuple[int, str], ...]", "aqt.reviewer.Reviewer", Card],
+            Tuple[Tuple[int, str], ...],
+        ],
+    ) -> None:
+        if cb in self._hooks:
+            self._hooks.remove(cb)
+
+    def count(self) -> int:
+        return len(self._hooks)
+
+    def __call__(
+        self,
+        buttons_tuple: Tuple[Tuple[int, str], ...],
+        reviewer: aqt.reviewer.Reviewer,
+        card: Card,
+    ) -> Tuple[Tuple[int, str], ...]:
+        for filter in self._hooks:
+            try:
+                buttons_tuple = filter(buttons_tuple, reviewer, card)
+            except:
+                # if the hook fails, remove it
+                self._hooks.remove(filter)
+                raise
+        return buttons_tuple
+
+
+reviewer_will_init_answer_buttons = _ReviewerWillInitAnswerButtonsFilter()
+
+
 class _ReviewerWillPlayAnswerSoundsHook:
     """Called before showing the answer/back side.
 

qt/aqt/reviewer.py

@@ -621,15 +621,16 @@ time = %(time)d;
         else:
             return 2
 
-    def _answerButtonList(self) -> Sequence[Tuple[int, str]]:
+    def _answerButtonList(self) -> Tuple[Tuple[int, str], ...]:
-        l = ((1, _("Again")),)
+        button_count = self.mw.col.sched.answerButtons(self.card)
-        cnt = self.mw.col.sched.answerButtons(self.card)
+        if button_count == 2:
-        if cnt == 2:
+            buttons_tuple: Tuple[Tuple[int, str], ...] = ((1, _("Again")), (2, _("Good")),)
-            return l + ((2, _("Good")),)
+        elif button_count == 3:
-        elif cnt == 3:
+            buttons_tuple = ((1, _("Again")), (2, _("Good")), (3, _("Easy")))
-            return l + ((2, _("Good")), (3, _("Easy")))
         else:
-            return l + ((2, _("Hard")), (3, _("Good")), (4, _("Easy")))
+            buttons_tuple = ((1, _("Again")), (2, _("Hard")), (3, _("Good")), (4, _("Easy")))
+        buttons_tuple = gui_hooks.reviewer_will_init_answer_buttons(buttons_tuple, self, self.card)
+        return buttons_tuple
 
     def _answerButtons(self) -> str:
         default = self._defaultEase()

qt/tools/genhooks_gui.py

@@ -58,6 +58,27 @@ hooks = [
         legacy_hook="showAnswer",
         legacy_no_args=True,
     ),
+    Hook(
+        name="reviewer_will_init_answer_buttons",
+        args=[
+            "buttons_tuple: Tuple[Tuple[int, str], ...]",
+            "reviewer: aqt.reviewer.Reviewer",
+            "card: Card",
+        ],
+        return_type="Tuple[Tuple[int, str], ...]",
+        doc="""Used to modify list of answer buttons
+
+        buttons_tuple is a tuple of buttons, with each button represented by a 
+        tuple containing an int for the button's ease and a string for the 
+        button's label.
+
+        Return a tuple of the form ((int, str), ...), e.g.:
+            ((1, "Label1"), (2, "Label2"), ...)
+
+        Note: import _ from anki.lang to support translation, using, e.g.,
+            ((1, _("Label1")), ...)
+        """,
+    ),
     Hook(
         name="reviewer_will_answer_card",
         args=[