DOCX Input: Ignore complex script font styles. Fixes conversion of documents that specify only complex script styles and no simple script styles. Fixes #1766650 [Private bug](https://bugs.launchpad.net/calibre/+bug/1766650)

src/calibre/ebooks/docx/block_styles.py

@@ -11,6 +11,8 @@ from collections import OrderedDict
 
 class Inherit:
     pass
+
+
 inherit = Inherit()
 
 
@@ -332,6 +334,7 @@ class ParagraphStyle(object):
         # Misc.
         'text_indent', 'text_align', 'line_height', 'background_color',
         'numbering', 'font_family', 'font_size', 'color', 'frame',
+        'cs_font_size', 'cs_font_family',
     )
 
     def __init__(self, namespace, pPr=None):
@@ -356,7 +359,7 @@ class ParagraphStyle(object):
             for s in namespace.XPath('./w:pStyle[@w:val]')(pPr):
                 self.linked_style = namespace.get(s, 'w:val')
 
-            self.font_family = self.font_size = self.color = inherit
+            self.font_family = self.font_size = self.color = self.cs_font_size = self.cs_font_family = inherit
 
         self._css = None
         self._border_key = None

src/calibre/ebooks/docx/char_styles.py

@@ -137,28 +137,41 @@ def read_position(parent, dest, XPath, get):
 
 def read_font(parent, dest, XPath, get):
     ff = inherit
-    used_cs = False
     for col in XPath('./w:rFonts')(parent):
         val = get(col, 'w:asciiTheme')
         if val:
             val = '|%s|' % val
         else:
             val = get(col, 'w:ascii')
-        if not val:
-            val = get(col, 'w:cs')
-            used_cs = bool(val)
         if val:
             ff = val
     setattr(dest, 'font_family', ff)
-    sizes = ('szCs', 'sz') if used_cs else ('sz', 'szCs')
-    for q in sizes:
-        for col in XPath('./w:%s[@w:val]' % q)(parent):
-            val = simple_float(get(col, 'w:val'), 0.5)
-            if val is not None:
-                setattr(dest, 'font_size', val)
-                return
+    for col in XPath('./w:sz[@w:val]')(parent):
+        val = simple_float(get(col, 'w:val'), 0.5)
+        if val is not None:
+            setattr(dest, 'font_size', val)
+            return
     setattr(dest, 'font_size', inherit)
 
+
+def read_font_cs(parent, dest, XPath, get):
+    ff = inherit
+    for col in XPath('./w:rFonts')(parent):
+        val = get(col, 'w:csTheme')
+        if val:
+            val = '|%s|' % val
+        else:
+            val = get(col, 'w:cs')
+        if val:
+            ff = val
+    setattr(dest, 'cs_font_family', ff)
+    for col in XPath('./w:szCS[@w:val]')(parent):
+        val = simple_float(get(col, 'w:val'), 0.5)
+        if val is not None:
+            setattr(dest, 'font_size', val)
+            return
+    setattr(dest, 'cs_font_size', inherit)
+
 # }}}
 
 
@@ -170,6 +183,7 @@ class RunStyle(object):
 
         'border_color', 'border_style', 'border_width', 'padding', 'color', 'highlight', 'background_color',
         'letter_spacing', 'font_size', 'text_decoration', 'vert_align', 'lang', 'font_family', 'position',
+        'cs_font_size', 'cs_font_family'
     }
 
     toggle_properties = {
@@ -191,6 +205,7 @@ class RunStyle(object):
                 setattr(self, p, binary_property(rPr, p, X, g))
 
             read_font(rPr, self, X, g)
+            read_font_cs(rPr, self, X, g)
             read_text_border(rPr, self, X, g)
             read_color(rPr, self, X, g)
             read_highlight(rPr, self, X, g)

src/calibre/ebooks/docx/styles.py

@@ -339,7 +339,7 @@ class Styles(object):
             has_links = '1' in {r.get('is-link', None) for r in runs}
             char_styles = [self.resolve_run(r) for r in runs]
             block_style = self.resolve_paragraph(p)
-            for prop in ('font_family', 'font_size', 'color'):
+            for prop in ('font_family', 'font_size', 'cs_font_family', 'cs_font_size', 'color'):
                 if has_links and prop == 'color':
                     # We cannot promote color as browser rendering engines will
                     # override the link color setting it to blue, unless the