From e878b52c99de94f3af17a7cd1c6aaf47d18b4432 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Sun, 28 Sep 2014 11:28:22 +0530
Subject: [PATCH] MOBI Output: Handle input documents that use CSS 3 syntax for
 colors by converting the color to the #RRGGBB format required for MOBI

---
 src/calibre/ebooks/mobi/mobiml.py | 7 ++++---
 src/calibre/ebooks/mobi/utils.py  | 9 +++++++++
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/calibre/ebooks/mobi/mobiml.py b/src/calibre/ebooks/mobi/mobiml.py
index 97d2ce3e77..966a3c2ee8 100644
--- a/src/calibre/ebooks/mobi/mobiml.py
+++ b/src/calibre/ebooks/mobi/mobiml.py
@@ -13,6 +13,7 @@ from calibre.ebooks.oeb.base import namespace, barename
 from calibre.ebooks.oeb.base import XHTML, XHTML_NS, urlnormalize
 from calibre.ebooks.oeb.stylizer import Stylizer
 from calibre.ebooks.oeb.transforms.flatcss import KeyMapper
+from calibre.ebooks.mobi.utils import convert_color_for_font_tag
 from calibre.utils.magick.draw import identify_data
 
 MBP_NS = 'http://mobipocket.com/ns/mbp'
@@ -125,7 +126,7 @@ class MobiMLizer(object):
             self.mobimlize_elem(body, stylizer, BlockState(nbody),
                                 [FormatState()])
             item.data = nroot
-            #print etree.tostring(nroot)
+            # print etree.tostring(nroot)
 
     def mobimlize_font(self, ptsize):
         return self.fnums[self.fmap[ptsize]]
@@ -280,10 +281,10 @@ class MobiMLizer(object):
                 inline = etree.SubElement(inline, XHTML('b'))
             if istate.bgcolor is not None and istate.bgcolor != 'transparent' :
                 inline = etree.SubElement(inline, XHTML('span'),
-                        bgcolor=istate.bgcolor)
+                        bgcolor=convert_color_for_font_tag(istate.bgcolor))
             if istate.fgcolor != 'black':
                 inline = etree.SubElement(inline, XHTML('font'),
-                        color=unicode(istate.fgcolor))
+                        color=convert_color_for_font_tag(istate.fgcolor))
             if istate.strikethrough:
                 inline = etree.SubElement(inline, XHTML('s'))
             if istate.underline:
diff --git a/src/calibre/ebooks/mobi/utils.py b/src/calibre/ebooks/mobi/utils.py
index d20fc5bcba..b01e057dbb 100644
--- a/src/calibre/ebooks/mobi/utils.py
+++ b/src/calibre/ebooks/mobi/utils.py
@@ -14,6 +14,7 @@ from io import BytesIO
 from calibre.utils.magick.draw import Image, save_cover_data_to, thumbnail
 from calibre.utils.imghdr import what
 from calibre.ebooks import normalize
+from tinycss.color3 import parse_color_string
 
 IMAGE_MAX_SIZE = 10 * 1024 * 1024
 RECORD_SIZE = 0x1000  # 4096 (Text record size (uncompressed))
@@ -604,3 +605,11 @@ def is_guide_ref_start(ref):
             (ref.type and ref.type.lower() in {'start',
                     'other.start', 'text'}))
 
+
+def convert_color_for_font_tag(val):
+    rgba = parse_color_string(unicode(val or ''))
+    if rgba is None or rgba == 'currentColor':
+        return val
+    clamp = lambda x: min(x, max(0, x), 1)
+    rgb = map(clamp, rgba[:3])
+    return '#' + ''.join(map(lambda x:'%02x' % int(x * 255), rgb))