GUI_draft_live.py

            self._advanced_widget.hide()
        # Force re-layout
        self.adjustSize()

    def open_circle_editor(self):
        """ Replace central widget with circle editor. """
        if not self._last_loaded_pixmap:
            print("No image loaded yet! Cannot open circle editor.")
            return

        old_widget = self.takeCentralWidget()
        self._old_central_widget = old_widget

        init_radius = self._circle_calibrated_radius
        editor = CircleEditorWidget(
            pixmap=self._last_loaded_pixmap,
            init_radius=init_radius,
            done_callback=self._on_circle_editor_done
        )
        self._editor = editor
        self.setCentralWidget(editor)

    def _on_circle_editor_done(self, final_radius):
        self._circle_calibrated_radius = final_radius
        print(f"Circle Editor done. Radius = {final_radius}")

        if self._last_loaded_file_path:
            cost_img = compute_cost_image(
                self._last_loaded_file_path,
                self._circle_calibrated_radius,
                clip_limit=self._current_clip_limit
            )
            self.image_view.cost_image_original = cost_img
            self.image_view.cost_image = cost_img.copy()
            self.image_view._apply_all_guide_points_to_cost()
            self.image_view._rebuild_full_path()
            self._update_advanced_images()

        editor_widget = self.takeCentralWidget()
        if editor_widget is not None:
            editor_widget.setParent(None)

        if self._old_central_widget is not None:
            self.setCentralWidget(self._old_central_widget)
            self._old_central_widget = None

        if self._editor is not None:
            self._editor.deleteLater()
            self._editor = None

    def toggle_rainbow(self):
        self.image_view.toggle_rainbow()

    def load_image(self):
        options = QFileDialog.Options()
        file_path, _ = QFileDialog.getOpenFileName(
            self, "Open Image", "",
            "Images (*.png *.jpg *.jpeg *.bmp *.tif)",
            options=options
        )
        if file_path:
            self.image_view.load_image(file_path)

            cost_img = compute_cost_image(
                file_path,
                self._circle_calibrated_radius,
                clip_limit=self._current_clip_limit
            )
            self.image_view.cost_image_original = cost_img
            self.image_view.cost_image = cost_img.copy()

            pm = QPixmap(file_path)
            if not pm.isNull():
                self._last_loaded_pixmap = pm

            self._last_loaded_file_path = file_path
            self._update_advanced_images()

    def update_contrast(self, clip_limit):
        self._current_clip_limit = clip_limit
        if self._last_loaded_file_path:
            cost_img = compute_cost_image(
                self._last_loaded_file_path,
                self._circle_calibrated_radius,
                clip_limit=clip_limit
            )
            self.image_view.cost_image_original = cost_img
            self.image_view.cost_image = cost_img.copy()
            self.image_view._apply_all_guide_points_to_cost()
            self.image_view._rebuild_full_path()

        self._update_advanced_images()

    def _update_advanced_images(self):
        if not self._last_loaded_pixmap:
            return
        pm_np = self._qpixmap_to_gray_float(self._last_loaded_pixmap)
        contrasted_blurred = preprocess_image(
            pm_np,
            sigma=3,
            clip_limit=self._current_clip_limit
        )
        cost_img_np = self.image_view.cost_image
        self._advanced_widget.update_displays(contrasted_blurred, cost_img_np)

    def _qpixmap_to_gray_float(self, qpix):
        img = qpix.toImage()
        img = img.convertToFormat(QImage.Format_ARGB32)
        ptr = img.bits()
        ptr.setsize(img.byteCount())
        arr = np.frombuffer(ptr, np.uint8).reshape((img.height(), img.width(), 4))
        rgb = arr[..., :3].astype(np.float32)
        gray = rgb.mean(axis=2) / 255.0
        return gray

    def export_path(self):
        full_xy = self.image_view.get_full_path_xy()
        if not full_xy:
            print("No path to export.")
            return

        options = QFileDialog.Options()
        file_path, _ = QFileDialog.getSaveFileName(
            self, "Export Path", "",
            "NumPy Files (*.npy);;All Files (*)",
            options=options
        )
        if file_path:
            arr = np.array(full_xy)
            np.save(file_path, arr)
            print(f"Exported path with {len(arr)} points to {file_path}")

    def clear_points(self):
        self.image_view.clear_guide_points()

    def closeEvent(self, event):
        super().closeEvent(event)


def main():
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())


if __name__ == "__main__":
    main()