fix: preserve colored blocks in PDF-to-Word (#500)

packages/ai/python/doc_to_word.py

@@ -13,13 +13,17 @@ def main():
         sys.exit(1)
     try:
         from pdf2docx import Converter
+        from pdf2docx_layout import install_pdf2docx_layout_fixes
     except ImportError:
         print(json.dumps({"error": "pdf2docx not installed"}))
         sys.exit(1)
     try:
+        install_pdf2docx_layout_fixes()
         cv = Converter(path)
-        cv.convert(out)
-        cv.close()
+        try:
+            cv.convert(out, max_border_width=2.0)
+        finally:
+            cv.close()
         print(json.dumps({"ok": True}))
     except Exception as exc:  # noqa: BLE001
         print(json.dumps({"error": str(exc)}))

packages/ai/python/pdf2docx_layout.py

@@ -0,0 +1,85 @@
+"""Targeted layout compatibility fixes for pdf2docx 0.5.13."""
+
+from docx.enum.table import WD_ROW_HEIGHT
+from docx.shared import Pt
+from pdf2docx.common import constants
+from pdf2docx.common.share import rgb_value
+from pdf2docx.layout.Blocks import Blocks
+from pdf2docx.table.Row import Row
+from pdf2docx.table.TableBlock import TableBlock
+
+
+_original_collect_stream_lines = Blocks.collect_stream_lines
+_original_table_make_docx = TableBlock.make_docx
+_original_row_make_docx = Row.make_docx
+_installed = False
+
+
+def _collect_stream_lines(
+    self, potential_shadings, line_separate_threshold, **kwargs
+):
+    groups = _original_collect_stream_lines(
+        self, potential_shadings, line_separate_threshold, **kwargs
+    )
+    fills = [
+        shape
+        for shape in potential_shadings
+        if not shape.is_determined and shape.color != rgb_value((1, 1, 1))
+    ]
+    merged = []
+    active_fill_ids = set()
+
+    for group in groups:
+        covered_fill_ids = {
+            id(fill)
+            for fill in fills
+            if any(
+                fill.contains(line, threshold=constants.FACTOR_MOST)
+                for line in group
+            )
+        }
+        if (
+            merged
+            and covered_fill_ids
+            and active_fill_ids.intersection(covered_fill_ids)
+        ):
+            merged[-1].extend(group)
+            active_fill_ids.update(covered_fill_ids)
+        else:
+            merged.append(group)
+            active_fill_ids = covered_fill_ids
+
+    return merged
+
+
+def _make_table_docx(self, table):
+    _original_table_make_docx(self, table)
+
+    if not self.is_stream_table_block or self.num_cols != 1:
+        return
+
+    cells = [cell for row in self for cell in row if cell]
+    if not cells or any(cell.bg_color is None for cell in cells):
+        return
+
+    table.columns[0].width = Pt(max(cell.bbox.width for cell in cells))
+
+
+def _make_row_docx(self, table, idx_row):
+    _original_row_make_docx(self, table, idx_row)
+
+    if any(cell and cell.bg_color is not None for cell in self):
+        table.rows[idx_row].height_rule = WD_ROW_HEIGHT.AT_LEAST
+
+
+def install_pdf2docx_layout_fixes() -> None:
+    """Install the pdf2docx layout compatibility wrappers exactly once."""
+    global _installed
+
+    if _installed:
+        return
+
+    Blocks.collect_stream_lines = _collect_stream_lines
+    TableBlock.make_docx = _make_table_docx
+    Row.make_docx = _make_row_docx
+    _installed = True