views: Extend PopUpConfirmationView to accept location parameter.

The parameter is useful for prompts that have long descriptions.

Author: preetmishra

zulipterminal/ui_tools/views.py

@@ -1256,9 +1256,16 @@ def __init__(self, controller: Any, title: str) -> None:
         super().__init__(controller, body, "MARKDOWN_HELP", popup_width, title, header)
 
 
+PopUpConfirmationViewLocation = Literal["top-left", "center"]
+
+
 class PopUpConfirmationView(urwid.Overlay):
     def __init__(
-        self, controller: Any, question: Any, success_callback: Callable[[], None]
+        self,
+        controller: Any,
+        question: Any,
+        success_callback: Callable[[], None],
+        location: PopUpConfirmationViewLocation = "top-left",
     ):
         self.controller = controller
         self.success_callback = success_callback
@@ -1268,19 +1275,31 @@ def __init__(
         no._w = urwid.AttrMap(urwid.SelectableIcon("No", 4), None, "selected")
         display_widget = urwid.GridFlow([yes, no], 3, 5, 1, "center")
         wrapped_widget = urwid.WidgetWrap(display_widget)
-        prompt = urwid.LineBox(
-            urwid.ListBox(
-                urwid.SimpleFocusListWalker([question, urwid.Divider(), wrapped_widget])
-            )
-        )
+        widgets = [question, urwid.Divider(), wrapped_widget]
+        prompt = urwid.LineBox(urwid.ListBox(urwid.SimpleFocusListWalker(widgets)))
+
+        if location == "top-left":
+            align = "left"
+            valign = "top"
+            width = LEFT_WIDTH + 1
+            height = 8
+        else:
+            align = "center"
+            valign = "middle"
+
+            max_cols, max_rows = controller.maximum_popup_dimensions()
+            # +2 to compensate for the LineBox characters.
+            width = min(max_cols, max(question.pack()[0], len("Yes"), len("No"))) + 2
+            height = min(max_rows, sum(widget.rows((width,)) for widget in widgets)) + 2
+
         urwid.Overlay.__init__(
             self,
             prompt,
             self.controller.view,
-            align="left",
-            valign="top",
-            width=LEFT_WIDTH + 1,
-            height=8,
+            align=align,
+            valign=valign,
+            width=width,
+            height=height,
         )
 
     def exit_popup_yes(self, args: Any) -> None: