When no margin detected, reserve a bit more space for comments

copienator/pdf_cut.py

@@ -6,6 +6,7 @@ from pathlib import Path
 import pymupdf
 
 from copienator.commands.splitting_int import _prepare_split_pages
+from copienator.annotation_layout import page_parts, save_parts
 
 # Percentages emitted by the GUI have six decimal places. Recover exact page
 # boundaries despite rounding, without turning nearby in-page cuts into breaks.
@@ -35,6 +36,7 @@ def cut_position(heights: list[float], percent: float) -> tuple[int, float]:
 
 def split_pdf(source: Path, percent: float, first_path: Path, second_path: Path) -> None:
     """Preserve whole pages; clip only the page actually crossed by the cut."""
+    parts = page_parts(source)
     with pymupdf.open(source) as document, pymupdf.open() as first, pymupdf.open() as second:
         index, offset = cut_position([page.rect.height for page in document], percent)
         if index:
@@ -55,3 +57,11 @@ def split_pdf(source: Path, percent: float, first_path: Path, second_path: Path)
                 second.insert_pdf(document, from_page=index + 1)
         first.save(first_path)
         second.save(second_path)
+        first_parts = [dict(part) for part in parts[:index + bool(offset)]]
+        second_parts = [dict(part) for part in parts[index:]]
+        if offset and 'crop_points' in parts[index]:
+            x0, y0, x1, y1 = parts[index]['crop_points']
+            first_parts[-1]['crop_points'] = [x0, y0, x1, y0 + offset]
+            second_parts[0]['crop_points'] = [x0, y0 + offset, x1, y1]
+        save_parts(first_path, first_parts)
+        save_parts(second_path, second_parts)