TXT Input: preserve spaces option

src/calibre/ebooks/txt/input.py

@@ -8,7 +8,8 @@ import os
 
 from calibre.customize.conversion import InputFormatPlugin, OptionRecommendation
 from calibre.ebooks.txt.processor import convert_basic, convert_markdown, \
-    separate_paragraphs_single_line, separate_paragraphs_print_formatted
+    separate_paragraphs_single_line, separate_paragraphs_print_formatted, \
+    preserve_spaces
 
 class TXTInput(InputFormatPlugin):
 
@@ -28,6 +29,9 @@ class TXTInput(InputFormatPlugin):
                 'an indent (either a tab or 2+ spaces) represents a paragraph. '
                 'Paragraphs end when the next line that starts with an indent '
                 'is reached.')),
+        OptionRecommendation(name='preserve_spaces', recommended_value=False,
+            help=_('Normally extra spaces are condensed into a single space. '
+                'With this option all spaces will be displayed.')),
         OptionRecommendation(name='markdown', recommended_value=False,
             help=_('Run the text input through the markdown pre-processor. To '
                 'learn more about markdown see')+' http://daringfireball.net/projects/markdown/'),
@@ -48,6 +52,8 @@ class TXTInput(InputFormatPlugin):
             txt = separate_paragraphs_single_line(txt)
         if options.print_formatted_paras:
             txt = separate_paragraphs_print_formatted(txt)
+        if options.preserve_spaces:
+            txt = preserve_spaces(txt)
 
         if options.markdown:
             log.debug('Running text though markdown conversion...')

src/calibre/ebooks/txt/processor.py

@@ -25,6 +25,9 @@ def convert_basic(txt, title=''):
         lines.append(line.strip())
     txt = '\n'.join(lines)
     
+    # Condense redundant spaces
+    txt = re.sub('[ ]{2,}', ' ', txt)
+
     # Remove blank lines from the beginning and end of the document.
     txt = re.sub('^\s+(?=.)', '', txt)
     txt = re.sub('(?<=.)\s+$', '', txt)
@@ -56,6 +59,11 @@ def separate_paragraphs_print_formatted(txt):
     txt = re.sub('(?miu)^(\t+|[ ]{2,})(?=.)', '\n\t', txt)
     return txt
 
+def preserve_spaces(txt):
+    txt = txt.replace(' ', '&nbsp;')
+    txt = txt.replace('\t', '&#09;')
+    return txt
+
 def opf_writer(path, opf_name, manifest, spine, mi):
     opf = OPFCreator(path, mi)
     opf.create_manifest(manifest)

src/calibre/gui2/convert/txt_input.py

@@ -14,6 +14,7 @@ class PluginWidget(Widget, Ui_Form):
 
     def __init__(self, parent, get_option, get_help, db=None, book_id=None):
         Widget.__init__(self, parent, 'txt_input',
-            ['single_line_paras', 'print_formatted_paras', 'markdown', 'markdown_disable_toc'])
+            ['single_line_paras', 'print_formatted_paras', 'markdown',
+                'markdown_disable_toc', 'preserve_spaces'])
         self.db, self.book_id = db, book_id
         self.initialize_options(get_option, get_help, db, book_id)

src/calibre/gui2/convert/txt_input.ui

@@ -6,7 +6,7 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>400</width>
+    <width>470</width>
     <height>300</height>
    </rect>
   </property>
@@ -52,7 +52,7 @@
      </property>
     </widget>
    </item>
-   <item row="5" column="0">
+   <item row="6" column="0">
     <spacer name="verticalSpacer">
      <property name="orientation">
       <enum>Qt::Vertical</enum>
@@ -65,10 +65,17 @@
      </property>
     </spacer>
    </item>
+   <item row="5" column="0">
+    <widget class="QCheckBox" name="opt_preserve_spaces">
+     <property name="text">
+      <string>Preserve &amp;spaces</string>
+     </property>
+    </widget>
+   </item>
   </layout>
  </widget>
  <resources/>
-<connections>
+ <connections>
   <connection>
    <sender>opt_markdown</sender>
    <signal>toggled(bool)</signal>