Also color quoted lines in HTML messages.

This makes reading HTML mail much more pleasing.

svn path=/trunk/KDE/kdepim/; revision=1002413

CMakeLists.txt

@@ -245,6 +245,7 @@ set(kmailprivate_LIB_SRCS
    stringutil.cpp
    iconnamecache.cpp
    mdnadvicedialog.cpp
+   htmlquotecolorer.cpp
    messagelistview/messageset.cpp
    messagelistview/pane.cpp
    messagelistview/storagemodel.cpp

htmlquotecolorer.cpp

@@ -0,0 +1,111 @@
+/* Copyright 2009 Thomas McGuire <mcguire@kde.org>
+
+   This library is free software; you can redistribute it and/or modify
+   it under the terms of the GNU Library General Public License as published
+   by the Free Software Foundation; either version 2 of the License or
+   ( at your option ) version 3 or, at the discretion of KDE e.V.
+   ( which shall act as a proxy as in section 14 of the GPLv3 ), any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public License
+   along with this library; see the file COPYING.LIB.  If not, write to
+   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.
+*/
+#include "htmlquotecolorer.h"
+
+#include "csshelper.h"
+
+#include <dom/html_document.h>
+#include <dom/dom_element.h>
+
+namespace KMail {
+
+HTMLQuoteColorer::HTMLQuoteColorer( KPIM::CSSHelper *cssHelper )
+  : mCSSHelper( cssHelper )
+{
+}
+
+QString HTMLQuoteColorer::process( const QString &htmlSource )
+{
+  // Create a DOM Document from the HTML source
+  DOM::HTMLDocument doc;
+  doc.open();
+  doc.write( htmlSource );
+  doc.close();
+
+  mIsQuotedLine = false;
+  mIsFirstTextNodeInLine = true;
+  processNode( doc.documentElement() );
+  return doc.toString().string();
+}
+
+DOM::Node HTMLQuoteColorer::processNode( DOM::Node node )
+{
+  // Below, we determine if the current text node should be quote colored by keeping track of
+  // linebreaks and wether this text node is the first one.
+  const QString textContent = node.textContent().string();
+  const bool isTextNode = !textContent.isEmpty() && !node.hasChildNodes();
+  if ( isTextNode ) {
+    if ( mIsFirstTextNodeInLine ) {
+      if ( textContent.simplified().startsWith( '>' ) ||
+          textContent.simplified().startsWith( '|' ) ) {
+        mIsQuotedLine = true;
+        currentQuoteLength = quoteLength( textContent ) - 1;
+      }
+      else {
+        mIsQuotedLine = false;
+      }
+    }
+
+    // All subsequent text nodes are not the first ones anymore
+    mIsFirstTextNodeInLine = false;
+  }
+
+  const QString nodeName = node.nodeName().string().toLower();
+  if ( nodeName == "br" || nodeName == "p" ) { // FIXME: Are there more newline nodes?
+    mIsFirstTextNodeInLine = true;
+  }
+
+  DOM::Node returnNode = node;
+  bool fontTagAdded = false;
+  if ( mIsQuotedLine && isTextNode ) {
+
+    // Ok, we are in a line that should be quoted, so create a font node for the color and replace
+    // the current node with it.
+    DOM::Element font = node.ownerDocument().createElement( QString( "font" ) );
+    font.setAttribute( QString( "color" ), mCSSHelper->quoteColor( currentQuoteLength ).name() );
+    node.parentNode().replaceChild( font, node );
+    font.appendChild( node );
+    returnNode = font;
+    fontTagAdded = true;
+  }
+
+  // Process all child nodes, but only if we are didn't add those child nodes itself, as otherwise
+  // we'll go into an infinite recursion.
+  if ( !fontTagAdded ) {
+    DOM::Node childNode = node.firstChild();
+    while ( !childNode.isNull() ) {
+      childNode = processNode( childNode );
+      childNode = childNode.nextSibling();
+    }
+  }
+  return returnNode;
+}
+
+int HTMLQuoteColorer::quoteLength( const QString &line ) const
+{
+  QString simplified = line.simplified();
+  simplified = simplified.replace( QRegExp( QLatin1String( "\\s" ) ), QString() )
+                         .replace( QLatin1Char( '|' ), QLatin1Char( '>' ) );
+  if ( simplified.startsWith( ">>>" ) ) return 3;
+  if ( simplified.startsWith( ">>" ) ) return 2;
+  if ( simplified.startsWith( ">" ) ) return 1;
+  return 0;
+}
+
+}

htmlquotecolorer.h

@@ -0,0 +1,64 @@
+/* Copyright 2009 Thomas McGuire <mcguire@kde.org>
+
+   This library is free software; you can redistribute it and/or modify
+   it under the terms of the GNU Library General Public License as published
+   by the Free Software Foundation; either version 2 of the License or
+   ( at your option ) version 3 or, at the discretion of KDE e.V.
+   ( which shall act as a proxy as in section 14 of the GPLv3 ), any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public License
+   along with this library; see the file COPYING.LIB.  If not, write to
+   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.
+*/
+#ifndef _HTMLQUOTECOLERER_H
+#define _HTMLQUOTECOLERER_H
+
+#include <dom/dom_node.h>
+
+namespace KPIM
+{
+  class CSSHelper;
+}
+
+namespace KMail
+{
+
+/**
+ * Little helper class that takes a HTML source as input and finds all
+ * lines that are quoted with '>' or '|'. The HTML text is then modified so
+ * that the quoted lines appear in the defined quote colors.
+ */
+class HTMLQuoteColorer
+{
+  public:
+
+    /** @param cssHelper the CSSHelper used for rendering, we get the quote colors from it */
+    explicit HTMLQuoteColorer( KPIM::CSSHelper *cssHelper );
+
+    /**
+     * Do the work and add nice colors to the HTML.
+     * @param htmlSource the input HTML code
+     * @return the modified HTML code
+     */
+    QString process( const QString &htmlSource );
+
+  private:
+
+    DOM::Node processNode( DOM::Node node );
+    int quoteLength( const QString &line ) const;
+
+    KPIM::CSSHelper *mCSSHelper;
+    bool mIsQuotedLine;
+    bool mIsFirstTextNodeInLine;
+    int currentQuoteLength;
+};
+
+}
+
+#endif

objecttreeparser.cpp

@@ -54,6 +54,7 @@
 #include "stringutil.h"
 #include "iconnamecache.h"
 #include "autoqpointer.h"
+#include "htmlquotecolorer.h"
 
 // other module headers
 #include <mimelib/enum.h>
@@ -985,6 +986,9 @@ bool ObjectTreeParser::okDecryptMIME( partNode& data,
     {
       if ( mReader->htmlMail() ) {
 
+        HTMLQuoteColorer colorer( cssHelper() );
+        bodyText = colorer.process( bodyText );
+
         // Strip <html>, <head>, and <body>, so we don't end up having those tags
         // twice, which confuses KHTML (especially with a signed
         // multipart/alternative message, the signature bars get rendered at the