feat: add comprehensive GitHub workflow and development tools

app/.venv/Lib/site-packages/weasyprint/pdf/pdfua.py

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+"""PDF/UA generation."""
+
+import pydyf
+
+from .metadata import add_metadata
+
+
+def pdfua(pdf, metadata, document, page_streams, attachments, compress):
+    """Set metadata for PDF/UA documents."""
+    # Structure for PDF tagging
+    content_mapping = pydyf.Dictionary({})
+    pdf.add_object(content_mapping)
+    structure_root = pydyf.Dictionary({
+        'Type': '/StructTreeRoot',
+        'ParentTree': content_mapping.reference,
+    })
+    pdf.add_object(structure_root)
+    structure_document = pydyf.Dictionary({
+        'Type': '/StructElem',
+        'S': '/Document',
+        'P': structure_root.reference,
+    })
+    pdf.add_object(structure_document)
+    structure_root['K'] = pydyf.Array([structure_document.reference])
+    pdf.catalog['StructTreeRoot'] = structure_root.reference
+
+    document_children = []
+    content_mapping['Nums'] = pydyf.Array()
+    links = []
+    for page_number, page_stream in enumerate(page_streams):
+        structure = {}
+        document.build_element_structure(structure)
+        parents = [None] * len(page_stream.marked)
+        for mcid, (key, box) in enumerate(page_stream.marked):
+            # Build structure elements
+            kids = [mcid]
+            if key == 'Link':
+                object_reference = pydyf.Dictionary({
+                    'Type': '/OBJR',
+                    'Obj': box.link_annotation.reference,
+                    'Pg': pdf.page_references[page_number],
+                })
+                pdf.add_object(object_reference)
+                links.append((object_reference.reference, box.link_annotation))
+            etree_element = box.element
+            child_structure_data_element = None
+            while True:
+                if etree_element is None:
+                    structure_data = structure.setdefault(
+                        box, {'parent': None})
+                else:
+                    structure_data = structure[etree_element]
+                new_element = 'element' not in structure_data
+                if new_element:
+                    child = structure_data['element'] = pydyf.Dictionary({
+                        'Type': '/StructElem',
+                        'S': f'/{key}',
+                        'K': pydyf.Array(kids),
+                        'Pg': pdf.page_references[page_number],
+                    })
+                    pdf.add_object(child)
+                    if key == 'LI':
+                        if etree_element.tag == 'dt':
+                            sub_key = 'Lbl'
+                        else:
+                            sub_key = 'LBody'
+                        real_child = pydyf.Dictionary({
+                            'Type': '/StructElem',
+                            'S': f'/{sub_key}',
+                            'K': pydyf.Array(kids),
+                            'Pg': pdf.page_references[page_number],
+                            'P': child.reference,
+                        })
+                        pdf.add_object(real_child)
+                        for kid in kids:
+                            if isinstance(kid, int):
+                                parents[kid] = real_child.reference
+                        child['K'] = pydyf.Array([real_child.reference])
+                        structure_data['element'] = real_child
+                    else:
+                        for kid in kids:
+                            if isinstance(kid, int):
+                                parents[kid] = child.reference
+                else:
+                    child = structure_data['element']
+                    child['K'].extend(kids)
+                    for kid in kids:
+                        if isinstance(kid, int):
+                            parents[kid] = child.reference
+                kid = child.reference
+                if child_structure_data_element is not None:
+                    child_structure_data_element['P'] = kid
+                if not new_element:
+                    break
+                kids = [kid]
+                child_structure_data_element = child
+                if structure_data['parent'] is None:
+                    child['P'] = structure_document.reference
+                    document_children.append(child.reference)
+                    break
+                else:
+                    etree_element = structure_data['parent']
+                key = page_stream.get_marked_content_tag(etree_element.tag)
+        content_mapping['Nums'].append(page_number)
+        content_mapping['Nums'].append(pydyf.Array(parents))
+    structure_document['K'] = pydyf.Array(document_children)
+    for i, (link, annotation) in enumerate(links, start=page_number + 1):
+        content_mapping['Nums'].append(i)
+        content_mapping['Nums'].append(link)
+        annotation['StructParent'] = i
+        annotation['F'] = 2 ** (2 - 1)
+
+    # Common PDF metadata stream
+    add_metadata(pdf, metadata, 'ua', 1, conformance=None, compress=compress)
+
+    # PDF document extra metadata
+    if 'Lang' not in pdf.catalog:
+        pdf.catalog['Lang'] = pydyf.String()
+    pdf.catalog['ViewerPreferences'] = pydyf.Dictionary({
+        'DisplayDocTitle': 'true',
+    })
+    pdf.catalog['MarkInfo'] = pydyf.Dictionary({'Marked': 'true'})
+
+
+VARIANTS = {'pdf/ua-1': (pdfua, {'mark': True})}