From d0a5b4b2a5f785ef87b7032900ad62ffce99be26 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 30 Jul 2020 17:58:21 +0530
Subject: [PATCH] DOCX Input: Leave undefined text colors in the input document
 as undefined (currentColor in CSS). Fixes #1888897 [Text color mangling
 converting from DOCX to
 EPUB/AZW3](https://bugs.launchpad.net/calibre/+bug/1888897)

---
 src/calibre/ebooks/docx/block_styles.py |  2 +-
 src/calibre/ebooks/docx/styles.py       | 10 +++++++---
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/calibre/ebooks/docx/block_styles.py b/src/calibre/ebooks/docx/block_styles.py
index fdd61add54..77c73508a0 100644
--- a/src/calibre/ebooks/docx/block_styles.py
+++ b/src/calibre/ebooks/docx/block_styles.py
@@ -46,7 +46,7 @@ def binary_property(parent, name, XPath, get):
     return True if val in {'on', '1', 'true'} else False
 
 
-def simple_color(col, auto='black'):
+def simple_color(col, auto='currentColor'):
     if not col or col == 'auto' or len(col) != 6:
         return auto
     return '#'+col
diff --git a/src/calibre/ebooks/docx/styles.py b/src/calibre/ebooks/docx/styles.py
index bf2eb930f1..a2400122b2 100644
--- a/src/calibre/ebooks/docx/styles.py
+++ b/src/calibre/ebooks/docx/styles.py
@@ -333,7 +333,7 @@ class Styles(object):
     def cascade(self, layers):
         self.body_font_family = 'serif'
         self.body_font_size = '10pt'
-        self.body_color = 'black'
+        self.body_color = 'currentColor'
 
         def promote_property(char_styles, block_style, prop):
             vals = {getattr(s, prop) for s in char_styles}
@@ -359,10 +359,12 @@ class Styles(object):
                     # The default text decoration is 'none'
                     s.text_decoration = inherit
 
-        def promote_most_common(block_styles, prop, default):
+        def promote_most_common(block_styles, prop, default, inherit_means=None):
             c = Counter()
             for s in block_styles:
                 val = getattr(s, prop)
+                if val is inherit and inherit_means is not None:
+                    val = inherit_means
                 if val is not inherit:
                     c[val] += 1
             val = None
@@ -370,6 +372,8 @@ class Styles(object):
                 val = c.most_common(1)[0][0]
                 for s in block_styles:
                     oval = getattr(s, prop)
+                    if oval is inherit and inherit_means is not None:
+                        oval = inherit_means
                     if oval is inherit:
                         if default != val:
                             setattr(s, prop, default)
@@ -387,7 +391,7 @@ class Styles(object):
         if fs is not None:
             self.body_font_size = '%.3gpt' % fs
 
-        color = promote_most_common(block_styles, 'color', self.body_color)
+        color = promote_most_common(block_styles, 'color', self.body_color, inherit_means='currentColor')
         if color is not None:
             self.body_color = color