Conversion: When inserting metadata as a jacket page, alter the font …

…sizes in the jacket so that the sizes match the sizes used in the rest of the book. Also pretty print the generated jacket HTML.

resources/jacket/stylesheet.css

@@ -38,7 +38,7 @@
 **	Title
 */
 table.cbj_header td.cbj_title {
-	font-size: x-large;
+	font-size: 1.5em;
 	font-style: italic;
 	text-align: center;
 }
@@ -47,15 +47,13 @@ table.cbj_header td.cbj_title {
 **	Series
 */
 table.cbj_header td.cbj_series {
-	font-size: medium;
 	text-align: center;
 }
 
 /*
 **	Author
 */
 table.cbj_header td.cbj_author {
-	font-size: medium;
 	text-align: center;
 }
 
@@ -141,14 +139,11 @@ hr {
 
 .cbj_footer {
 	font-family: sans-serif;
-	font-size: small;
+	font-size: 0.8em;
 	margin-top: 8px;
 	text-align: center;
 	}
-.cbj_smallcaps {
-	font-size: 90%;
-	}
 
 .cbj_comments {
-	font-family: sans-serif;
+	font-family: sans-serif; 
 	}

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

@@ -91,7 +91,7 @@ def insert_metadata(self, mi):
 
         root = render_jacket(mi, self.opts.output_profile,
                 alt_title=title, alt_tags=tags,
-                alt_comments=comments)
+                alt_comments=comments, rescale_fonts=True)
         id, href = self.oeb.manifest.generate('calibre_jacket', 'jacket.xhtml')
 
         jacket = self.oeb.manifest.add(id, href, guess_type(href)[0], data=root)
@@ -144,7 +144,7 @@ def get_rating(rating, rchar, e_rchar):
 
 def render_jacket(mi, output_profile,
         alt_title=_('Unknown'), alt_tags=[], alt_comments='',
-        alt_publisher=('')):
+        alt_publisher=(''), rescale_fonts=False):
     css = P('jacket/stylesheet.css', data=True).decode('utf-8')
 
     try:
@@ -268,6 +268,24 @@ def generate_html(comments):
         except:
             root = etree.fromstring(generate_html(''),
                 parser=RECOVER_PARSER)
+    if rescale_fonts:
+        # We ensure that the conversion pipeline will set the font sizes for
+        # text in the jacket to the same size as the font sizes for the rest of
+        # the text in the book. That means that as long as the jacket uses
+        # relative font sizes (em or %), the post conversion font size will be
+        # the same as for text in the main book. So text with size x em will
+        # be rescaled to the same value in both the jacket and the main content.
+        #
+        # We cannot use calibre_rescale_100 on the body tag as that will just
+        # give the body tag a font size of 1em, which is useless.
+        for body in root.xpath('//*[local-name()="body"]'):
+            fw = body.makeelement(XHTML('div'))
+            fw.set('class', 'calibre_rescale_100')
+            for child in body:
+                fw.append(child)
+            body.append(fw)
+    from calibre.ebooks.oeb.polish.pretty import pretty_html_tree
+    pretty_html_tree(None, root)
     return root
 
 # }}}