Preserve styles WiP

Author: buchi

docxcompose/composer.py

@@ -15,6 +15,7 @@
 
 from docxcompose.image import ImageWrapper
 from docxcompose.properties import CustomProperties
+from docxcompose.utils import increment_name
 from docxcompose.utils import NS
 from docxcompose.utils import xpath
 
@@ -41,6 +42,7 @@ def __init__(self, doc):
         self.pkg = doc.part.package
 
         self.restart_numbering = True
+        self.preserve_styles = True
 
         self.reset_reference_mapping()
 
@@ -59,6 +61,7 @@ def append(self, doc, remove_property_fields=True):
     def insert(self, index, doc, remove_property_fields=True):
         """Insert the given document at the given index."""
         self.reset_reference_mapping()
+        self._preserved_styles = {}
 
         # Remove custom property fields but keep the values
         if remove_property_fields:
@@ -299,24 +302,30 @@ def add_styles(self, doc, element):
 
         for style_id in used_style_ids:
             our_style_id = self.mapped_style_id(style_id)
-            if our_style_id not in our_style_ids:
+            if self.preserve_styles and our_style_id in our_style_ids:
+                if our_style_id not in self._preserved_styles:
+                    style_element = deepcopy(doc.styles.element.get_by_id(style_id))
+                    our_style_element = self.doc.styles.element.get_by_id(our_style_id)
+                    if style_element.xml != our_style_element.xml:
+                        new_id = increment_name(our_style_id)
+                        new_name = increment_name(style_element.name.val)
+                        while new_id in our_style_ids:
+                            new_id = increment_name(new_id)
+                            new_name = increment_name(new_name)
+                        style_element.styleId = new_id
+                        style_element.name.val = new_name
+                        self.doc.styles.element.append(style_element)
+                        self.add_numberings(doc, style_element)
+                        self.add_linked_styles(doc, style_element)
+                        self._preserved_styles[our_style_id] = style_element.styleId
+                for el in xpath(element, ".//w:tblStyle|.//w:pStyle|.//w:rStyle"):
+                    el.val = self._preserved_styles[our_style_id]
+            elif our_style_id not in our_style_ids:
                 style_element = deepcopy(doc.styles.element.get_by_id(style_id))
                 if style_element is not None:
                     self.doc.styles.element.append(style_element)
                     self.add_numberings(doc, style_element)
-                    # Also add linked styles
-                    linked_style_ids = xpath(style_element, ".//w:link/@w:val")
-                    if linked_style_ids:
-                        linked_style_id = linked_style_ids[0]
-                        our_linked_style_id = self.mapped_style_id(linked_style_id)
-                        if our_linked_style_id not in our_style_ids:
-                            our_linked_style = doc.styles.element.get_by_id(
-                                linked_style_id
-                            )
-                            if our_linked_style is not None:
-                                self.doc.styles.element.append(
-                                    deepcopy(our_linked_style)
-                                )
+                    self.add_linked_styles(doc, style_element)
             else:
                 # Create a mapping for abstractNumIds used in existing styles
                 # This is used when adding numberings to avoid having multiple
@@ -360,6 +369,21 @@ def add_styles(self, doc, element):
             # Update our style ids
             our_style_ids = [s.style_id for s in self.doc.styles]
 
+    def add_linked_styles(self, doc, element):
+        linked_style_ids = xpath(element, ".//w:link/@w:val")
+        if linked_style_ids:
+            linked_style_id = linked_style_ids[0]
+            our_linked_style_id = self.mapped_style_id(linked_style_id)
+            our_style_ids = [s.style_id for s in self.doc.styles]
+            if our_linked_style_id not in our_style_ids:
+                our_linked_style = doc.styles.element.get_by_id(
+                    linked_style_id
+                )
+                if our_linked_style is not None:
+                    self.doc.styles.element.append(
+                        deepcopy(our_linked_style)
+                    )
+
     def add_numberings(self, doc, element):
         """Add numberings from the given document used in the given element."""
         # Search for numbering references

docxcompose/utils.py

@@ -48,3 +48,12 @@ def word_to_python_date_format(format_str):
     for word_format, python_format in date_format_map:
         format_str = re.sub(word_format, python_format, format_str)
     return format_str
+
+
+def increment_name(name):
+    increment_part = name.split('_')[-1]
+    try:
+        increment = int(increment_part)
+    except ValueError:
+        return f'{name}_1'
+    return f'{name.removesuffix(increment_part)}{increment + 1}'