decompiler: grayed 'decompiling…' overlay during (re)decompile

When a decompile runs (tab to pseudocode, or an implicit refresh after rename),
DecompView.loading covers the pane with a centered, grayed '― decompiling… ―'
(custom get_loading_widget + .decomp-loading CSS), cleared when the body arrives.

The loading cover blurs the widget, which made Tab fall back to focus-nav instead
of toggling; made the app Tab/Shift+Tab binding priority so it toggles regardless
of focus, and restore focus to the pane when the decompile finishes.

pilot suite 55/55 (adds overlay-shown / overlay-cleared).

2 files changed, 32 insertions, 1 deletions

diff --git a/idatui/app.py b/idatui/app.py
index a6affa2..88e1dea 100644
--- a/idatui/app.py
+++ b/idatui/app.py
@@ -835,6 +835,10 @@ class DecompView(SearchMixin, NavMixin, ColumnCursor, ScrollView, can_focus=True
             self._hscroll()
         self.refresh()
 
+    def get_loading_widget(self):  # type: ignore[override]
+        # Shown (grayed, centered) while a (re)decompile is in flight.
+        return Static("― decompiling… ―", classes="decomp-loading")
+
     def _line_ea(self, idx: int) -> int | None:
         if not (0 <= idx < len(self._texts)):
             return None
@@ -972,6 +976,10 @@ class IdaTui(App):
         background: $warning-darken-2; color: $text;
     }
     #status { height: 1; background: $panel; color: $text; padding: 0 1; }
+    .decomp-loading {
+        width: 100%; height: 100%; content-align: center middle;
+        background: $panel-darken-1; color: $text-muted; text-style: italic bold;
+    }
     XrefsScreen { align: center middle; }
     #xref-box { width: 84; max-height: 70%; height: auto; border: thick $accent; background: $panel; }
     #xref-title { dock: top; height: 1; background: $accent; color: $text; padding: 0 1; }
@@ -983,7 +991,7 @@ class IdaTui(App):
         Binding("slash", "filter", "Filter"),
         Binding("g", "goto", "Goto"),
         Binding("ctrl+b", "toggle_functions", "Names"),
-        Binding("tab,shift+tab", "toggle_view", "Disasm/Pseudocode"),
+        Binding("tab,shift+tab", "toggle_view", "Disasm/Pseudocode", priority=True),
         Binding("ctrl+s", "save", "Save"),
         Binding("escape", "back", "Back"),
     ]
@@ -1670,6 +1678,7 @@ class IdaTui(App):
             dec.focus()
             if self._cur is not None and dec.loaded_ea != self._cur.ea:
                 self._status(f"{self._cur.name} — decompiling…")
+                dec.loading = True  # gray out + 'decompiling…' overlay
                 self._load_decomp(self._cur.ea, self._cur.name)
             else:
                 self._status_for_cur("pseudocode")
@@ -1686,6 +1695,9 @@ class IdaTui(App):
 
     def _apply_decomp(self, ea: int, name: str, dec) -> None:  # type: ignore[no-untyped-def]
         view = self.query_one(DecompView)
+        view.loading = False
+        if self._active == "decomp":
+            view.focus()  # loading cover had blurred it; restore focus
         # Restore the saved pseudocode position when returning to this function.
         cur = self._cur
         same = cur is not None and cur.ea == ea
diff --git a/tests/test_tui.py b/tests/test_tui.py
index 884b1c3..494ea4a 100644
--- a/tests/test_tui.py
+++ b/tests/test_tui.py
@@ -157,6 +157,25 @@ async def run(db):
               app._active == "disasm" and dis.display and not dec.display,
               f"active={app._active}")
 
+        # A (re)decompile shows a grayed 'decompiling…' overlay while it runs.
+        await pilot.press("tab")
+        await wait_until(pilot, lambda: app._active == "decomp", timeout=10)
+        await wait_until(pilot, lambda: dec.loaded_ea is not None, timeout=20)
+        dec.loaded_ea = None            # force a reload (as rename/refresh does)
+        app._show_active()
+        cover = dec._cover_widget
+        check("decompile shows a 'decompiling…' overlay",
+              dec.loading and cover is not None
+              and "decomp-loading" in cover.classes
+              and "decompiling" in str(cover.render()),
+              f"loading={dec.loading} cover={cover!r}")
+        await wait_until(pilot, lambda: not dec.loading and dec._cover_widget is None,
+                         timeout=25)
+        check("overlay clears when the decompile finishes",
+              not dec.loading and dec._cover_widget is None)
+        await pilot.press("tab")  # back to disasm for the rest of the tests
+        await wait_until(pilot, lambda: app._active == "disasm", timeout=10)
+
         # Vim-style search in the disassembly view.
         line0 = dis.model.cached_line(0)
         raw = (line0.text.split() or ["push"])[0] if line0 else "push"