Conversion: Add an option under Look & Feel to remove specified style information (CSS) from the document during conversion. Fixes #871384 (Font Selection)

src/calibre/ebooks/conversion/cli.py

@@ -134,7 +134,7 @@ def add_pipeline_options(parser, plumber):
                       'font_size_mapping',
                       'line_height', 'minimum_line_height',
                       'linearize_tables',
-                      'extra_css',
+                      'extra_css', 'filter_css',
                       'smarten_punctuation', 'unsmarten_punctuation',
                       'margin_top', 'margin_left', 'margin_right',
                       'margin_bottom', 'change_justification',

src/calibre/ebooks/conversion/plumber.py

@@ -308,6 +308,16 @@ OptionRecommendation(name='extra_css',
                 'rules.')
         ),
 
+OptionRecommendation(name='filter_css',
+            recommended_value=None, level=OptionRecommendation.LOW,
+            help=_('A comma separated list of CSS properties that '
+                'will be removed from all CSS style rules. This is useful '
+                'if the presence of some style information prevents it '
+                'from being overridden on your device. '
+                'For example: '
+                'font-family,color,margin-left,margin-right')
+        ),
+
 OptionRecommendation(name='page_breaks_before',
             recommended_value="//*[name()='h1' or name()='h2']",
             level=OptionRecommendation.LOW,

src/calibre/ebooks/oeb/transforms/flatcss.py

@@ -118,8 +118,20 @@ class CSSFlattener(object):
 
     def __call__(self, oeb, context):
         oeb.logger.info('Flattening CSS and remapping font sizes...')
+        self.context = self.opts =context
         self.oeb = oeb
-        self.context = context
+
+        self.filter_css = frozenset()
+        if self.opts.filter_css:
+            try:
+                self.filter_css = frozenset([x.strip().lower() for x in
+                    self.opts.filter_css.split(',')])
+            except:
+                self.oeb.log.warning('Failed to parse filter_css, ignoring')
+            else:
+                self.oeb.log.debug('Filtering CSS properties: %s'%
+                    ', '.join(self.filter_css))
+
         self.stylize_spine()
         self.sbase = self.baseline_spine() if self.fbase else None
         self.fmap = FontMapper(self.sbase, self.fbase, self.fkey)
@@ -279,6 +291,10 @@ class CSSFlattener(object):
         except:
             self.oeb.logger.exception('Failed to set minimum line-height')
 
+        if cssdict:
+            for x in self.filter_css:
+                cssdict.pop(x, None)
+
         if cssdict:
             if self.lineh and self.fbase and tag != 'body':
                 self.clean_edges(cssdict, style, psize)
@@ -311,7 +327,6 @@ class CSSFlattener(object):
             lineh = self.lineh / psize
             cssdict['line-height'] = "%0.5fem" % lineh
 
-
         if (self.context.remove_paragraph_spacing or
                 self.context.insert_blank_line) and tag in ('p', 'div'):
             if item_id != 'calibre_jacket' or self.context.output_profile.name == 'Kindle':

src/calibre/gui2/convert/look_and_feel.py

@@ -18,6 +18,16 @@ class LookAndFeelWidget(Widget, Ui_Form):
     HELP  = _('Control the look and feel of the output')
     COMMIT_NAME = 'look_and_feel'
 
+    FILTER_CSS = {
+            'fonts': {'font-family'},
+            'margins': {'margin', 'margin-left', 'margin-right', 'margin-top',
+                'margin-bottom'},
+            'padding':  {'padding', 'padding-left', 'padding-right', 'padding-top',
+                'padding-bottom'},
+            'floats': {'float'},
+            'colors': {'color', 'background', 'background-color'},
+    }
+
     def __init__(self, parent, get_option, get_help, db=None, book_id=None):
         Widget.__init__(self, parent,
                 ['change_justification', 'extra_css', 'base_font_size',
@@ -27,7 +37,7 @@ class LookAndFeelWidget(Widget, Ui_Form):
                     'remove_paragraph_spacing',
                     'remove_paragraph_spacing_indent_size',
                     'insert_blank_line_size',
-                    'input_encoding',
+                    'input_encoding', 'filter_css',
                     'asciiize', 'keep_ligatures',
                     'linearize_tables']
                 )
@@ -56,6 +66,15 @@ class LookAndFeelWidget(Widget, Ui_Form):
         if g is self.opt_change_justification:
             ans = unicode(g.itemData(g.currentIndex()).toString())
             return ans
+        if g is self.opt_filter_css:
+            ans = set()
+            for key, item in self.FILTER_CSS.iteritems():
+                w = getattr(self, 'filter_css_%s'%key)
+                if w.isChecked():
+                    ans = ans.union(item)
+            ans = ans.union(set([x.strip().lower() for x in
+                unicode(self.filter_css_others.text()).split(',')]))
+            return ','.join(ans) if ans else None
         return Widget.get_value_handler(self, g)
 
     def set_value_handler(self, g, val):
@@ -66,6 +85,27 @@ class LookAndFeelWidget(Widget, Ui_Form):
                     g.setCurrentIndex(i)
                     break
             return True
+        if g is self.opt_filter_css:
+            if not val: val = ''
+            items = frozenset([x.strip().lower() for x in val.split(',')])
+            for key, vals in self.FILTER_CSS.iteritems():
+                w = getattr(self, 'filter_css_%s'%key)
+                if not vals - items:
+                    items = items - vals
+                    w.setChecked(True)
+                else:
+                    w.setChecked(False)
+            self.filter_css_others.setText(', '.join(items))
+            return True
+
+    def connect_gui_obj_handler(self, gui_obj, slot):
+        if gui_obj is self.opt_filter_css:
+            for key in self.FILTER_CSS:
+                w = getattr(self, 'filter_css_%s'%key)
+                w.stateChanged.connect(slot)
+            self.filter_css_others.textChanged.connect(slot)
+            return
+        raise NotImplementedError()
 
     def font_key_wizard(self):
         from calibre.gui2.convert.font_key import FontKeyChooser

src/calibre/gui2/convert/look_and_feel.ui

@@ -6,7 +6,7 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>642</width>
+    <width>655</width>
     <height>522</height>
    </rect>
   </property>
@@ -164,6 +164,41 @@
      </property>
     </widget>
    </item>
+   <item row="6" column="3">
+    <widget class="QLabel" name="label_4">
+     <property name="text">
+      <string>&amp;Indent size:</string>
+     </property>
+     <property name="alignment">
+      <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+     </property>
+     <property name="buddy">
+      <cstring>opt_remove_paragraph_spacing_indent_size</cstring>
+     </property>
+    </widget>
+   </item>
+   <item row="6" column="4">
+    <widget class="QDoubleSpinBox" name="opt_remove_paragraph_spacing_indent_size">
+     <property name="toolTip">
+      <string>&lt;p&gt;When calibre removes inter paragraph spacing, it automatically sets a paragraph indent, to ensure that paragraphs can be easily distinguished. This option controls the width of that indent.</string>
+     </property>
+     <property name="specialValueText">
+      <string>No change</string>
+     </property>
+     <property name="suffix">
+      <string> em</string>
+     </property>
+     <property name="decimals">
+      <number>1</number>
+     </property>
+     <property name="minimum">
+      <double>-0.100000000000000</double>
+     </property>
+     <property name="singleStep">
+      <double>0.100000000000000</double>
+     </property>
+    </widget>
+   </item>
    <item row="7" column="0" colspan="2">
     <widget class="QCheckBox" name="opt_insert_blank_line">
      <property name="text">
@@ -171,6 +206,19 @@
      </property>
     </widget>
    </item>
+   <item row="7" column="3">
+    <widget class="QLabel" name="label_7">
+     <property name="text">
+      <string>&amp;Line size:</string>
+     </property>
+     <property name="alignment">
+      <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+     </property>
+     <property name="buddy">
+      <cstring>opt_insert_blank_line_size</cstring>
+     </property>
+    </widget>
+   </item>
    <item row="7" column="4">
     <widget class="QDoubleSpinBox" name="opt_insert_blank_line_size">
      <property name="suffix">
@@ -194,80 +242,6 @@
    <item row="8" column="2" colspan="3">
     <widget class="QComboBox" name="opt_change_justification"/>
    </item>
-   <item row="9" column="1" colspan="4">
-    <widget class="QCheckBox" name="opt_asciiize">
-     <property name="text">
-      <string>&amp;Transliterate unicode characters to ASCII</string>
-     </property>
-    </widget>
-   </item>
-   <item row="10" column="1" colspan="2">
-    <widget class="QCheckBox" name="opt_keep_ligatures">
-     <property name="text">
-      <string>Keep &amp;ligatures</string>
-     </property>
-    </widget>
-   </item>
-   <item row="13" column="0" colspan="5">
-    <widget class="QGroupBox" name="groupBox">
-     <property name="title">
-      <string>Extra &amp;CSS</string>
-     </property>
-     <layout class="QGridLayout" name="gridLayout_3">
-      <item row="0" column="0">
-       <widget class="QTextEdit" name="opt_extra_css"/>
-      </item>
-     </layout>
-    </widget>
-   </item>
-   <item row="6" column="4">
-    <widget class="QDoubleSpinBox" name="opt_remove_paragraph_spacing_indent_size">
-     <property name="toolTip">
-      <string>&lt;p&gt;When calibre removes inter paragraph spacing, it automatically sets a paragraph indent, to ensure that paragraphs can be easily distinguished. This option controls the width of that indent.</string>
-     </property>
-     <property name="specialValueText">
-      <string>No change</string>
-     </property>
-     <property name="suffix">
-      <string> em</string>
-     </property>
-     <property name="decimals">
-      <number>1</number>
-     </property>
-     <property name="minimum">
-      <double>-0.100000000000000</double>
-     </property>
-     <property name="singleStep">
-      <double>0.100000000000000</double>
-     </property>
-    </widget>
-   </item>
-   <item row="6" column="3">
-    <widget class="QLabel" name="label_4">
-     <property name="text">
-      <string>&amp;Indent size:</string>
-     </property>
-     <property name="alignment">
-      <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
-     </property>
-     <property name="buddy">
-      <cstring>opt_remove_paragraph_spacing_indent_size</cstring>
-     </property>
-    </widget>
-   </item>
-   <item row="7" column="3">
-    <widget class="QLabel" name="label_7">
-     <property name="text">
-      <string>&amp;Line size:</string>
-     </property>
-     <property name="alignment">
-      <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
-     </property>
-     <property name="buddy">
-      <cstring>opt_insert_blank_line_size</cstring>
-     </property>
-    </widget>
-   </item>
    <item row="9" column="0">
     <widget class="QCheckBox" name="opt_smarten_punctuation">
      <property name="text">
@@ -275,6 +249,13 @@
      </property>
     </widget>
    </item>
+   <item row="9" column="1" colspan="4">
+    <widget class="QCheckBox" name="opt_asciiize">
+     <property name="text">
+      <string>&amp;Transliterate unicode characters to ASCII</string>
+     </property>
+    </widget>
+   </item>
    <item row="10" column="0">
     <widget class="QCheckBox" name="opt_unsmarten_punctuation">
      <property name="text">
@@ -282,6 +263,13 @@
      </property>
     </widget>
    </item>
+   <item row="10" column="1" colspan="2">
+    <widget class="QCheckBox" name="opt_keep_ligatures">
+     <property name="text">
+      <string>Keep &amp;ligatures</string>
+     </property>
+    </widget>
+   </item>
    <item row="10" column="3">
     <widget class="QCheckBox" name="opt_linearize_tables">
      <property name="text">
@@ -289,6 +277,111 @@
      </property>
     </widget>
    </item>
+   <item row="11" column="0" colspan="5">
+    <widget class="QTabWidget" name="tabWidget">
+     <property name="currentIndex">
+      <number>0</number>
+     </property>
+     <widget class="QWidget" name="extra_css_tab">
+      <attribute name="title">
+       <string>&amp;Extra CSS</string>
+      </attribute>
+      <layout class="QGridLayout" name="gridLayout_2">
+       <item row="0" column="0">
+        <widget class="QTextEdit" name="opt_extra_css"/>
+       </item>
+      </layout>
+     </widget>
+     <widget class="QWidget" name="opt_filter_css">
+      <attribute name="title">
+       <string>&amp;Filter Style Information</string>
+      </attribute>
+      <layout class="QGridLayout" name="gridLayout_3">
+       <item row="0" column="0" colspan="5">
+        <widget class="QLabel" name="label_8">
+         <property name="text">
+          <string>Select what style information you want completely removed:</string>
+         </property>
+         <property name="wordWrap">
+          <bool>true</bool>
+         </property>
+        </widget>
+       </item>
+       <item row="1" column="0">
+        <widget class="QCheckBox" name="filter_css_fonts">
+         <property name="toolTip">
+          <string>Removes the font-family CSS property</string>
+         </property>
+         <property name="text">
+          <string>&amp;Fonts</string>
+         </property>
+        </widget>
+       </item>
+       <item row="1" column="1">
+        <widget class="QCheckBox" name="filter_css_margins">
+         <property name="toolTip">
+          <string>Removes the margin CSS properties. Note that page margins are not affected by this setting.</string>
+         </property>
+         <property name="text">
+          <string>&amp;Margins</string>
+         </property>
+        </widget>
+       </item>
+       <item row="1" column="2">
+        <widget class="QCheckBox" name="filter_css_padding">
+         <property name="toolTip">
+          <string>Removes the padding CSS properties</string>
+         </property>
+         <property name="text">
+          <string>&amp;Padding</string>
+         </property>
+        </widget>
+       </item>
+       <item row="1" column="3">
+        <widget class="QCheckBox" name="filter_css_floats">
+         <property name="toolTip">
+          <string>Convert floating images/text into static images/text</string>
+         </property>
+         <property name="text">
+          <string>F&amp;loats</string>
+         </property>
+        </widget>
+       </item>
+       <item row="1" column="4">
+        <widget class="QCheckBox" name="filter_css_colors">
+         <property name="toolTip">
+          <string>Removes foreground and background colors</string>
+         </property>
+         <property name="text">
+          <string>&amp;Colors</string>
+         </property>
+        </widget>
+       </item>
+       <item row="2" column="0" colspan="5">
+        <layout class="QHBoxLayout" name="horizontalLayout_2">
+         <item>
+          <widget class="QLabel" name="label_9">
+           <property name="text">
+            <string>&amp;Other CSS Properties:</string>
+           </property>
+           <property name="buddy">
+            <cstring>filter_css_others</cstring>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLineEdit" name="filter_css_others">
+           <property name="toolTip">
+            <string>Comma separated list of CSS properties to remove. For example: display, color, font-family</string>
+           </property>
+          </widget>
+         </item>
+        </layout>
+       </item>
+      </layout>
+     </widget>
+    </widget>
+   </item>
   </layout>
  </widget>
  <customwidgets>