urlhandlermanager.cpp

/*
    urlhandlermanager.cpp
 
    This file is part of KMail, the KDE mail client.
    Copyright (c) 2002-2003 Klarälvdalens Datakonsult AB
    Copyright (c) 2003      Marc Mutz <mutz@kde.org>
 
    KMail is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License, version 2, as
    published by the Free Software Foundation.
 
    KMail 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
    General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 
    In addition, as a special exception, the copyright holders give
    permission to link the code of this program with any edition of
    the TQt library by Trolltech AS, Norway (or with modified versions
    of TQt that use the same license as TQt), and distribute linked
    combinations including the two.  You must obey the GNU General
    Public License in all respects for all of the code used other than
    TQt.  If you modify this file, you may extend this exception to
    your version of the file, but you are not obligated to do so.  If
    you do not wish to do so, delete this exception statement from
    your version.
*/
 
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
 
#include "urlhandlermanager.h"
 
#include "interfaces/urlhandler.h"
#include "interfaces/bodyparturlhandler.h"
#include "partNode.h"
#include "partnodebodypart.h"
#include "kmreaderwin.h"
#include "kmkernel.h"
#include "callback.h"
#include "stl_util.h"
 
#include <kstandarddirs.h>
#include <kurldrag.h>
#include <tdeimproxy.h>
#include <kurl.h>
 
#include <algorithm>
using std::for_each;
using std::remove;
using std::find;
 
KMail::URLHandlerManager * KMail::URLHandlerManager::self = 0;
 
namespace {
  class KMailProtocolURLHandler : public KMail::URLHandler {
  public:
    KMailProtocolURLHandler() : KMail::URLHandler() {}
    ~KMailProtocolURLHandler() {}
 
    bool handleClick( const KURL &, KMReaderWin * ) const;
    bool handleContextMenuRequest( const KURL & url, const TQPoint &, KMReaderWin * ) const {
      return url.protocol() == "kmail";
    }
    TQString statusBarMessage( const KURL &, KMReaderWin * ) const;
  };
 
  class ExpandCollapseQuoteURLManager : public KMail::URLHandler {
  public:
    ExpandCollapseQuoteURLManager() : KMail::URLHandler() {}
    ~ExpandCollapseQuoteURLManager() {}
 
    bool handleClick( const KURL &, KMReaderWin * ) const;
    bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const {
      return false;
    }
    TQString statusBarMessage( const KURL &, KMReaderWin * ) const;
 
  };
 
  class SMimeURLHandler : public KMail::URLHandler {
  public:
    SMimeURLHandler() : KMail::URLHandler() {}
    ~SMimeURLHandler() {}
 
    bool handleClick( const KURL &, KMReaderWin * ) const;
    bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const {
      return false;
    }
    TQString statusBarMessage( const KURL &, KMReaderWin * ) const;
  };
 
  class MailToURLHandler : public KMail::URLHandler {
  public:
    MailToURLHandler() : KMail::URLHandler() {}
    ~MailToURLHandler() {}
 
    bool handleClick( const KURL &, KMReaderWin * ) const { return false; }
    bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const {
      return false;
    }
    TQString statusBarMessage( const KURL &, KMReaderWin * ) const;
  };
 
  class HtmlAnchorHandler : public KMail::URLHandler {
  public:
    HtmlAnchorHandler() : KMail::URLHandler() {}
    ~HtmlAnchorHandler() {}
 
    bool handleClick( const KURL &, KMReaderWin * ) const;
    bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const {
      return false;
    }
    TQString statusBarMessage( const KURL &, KMReaderWin * ) const { return TQString(); }
  };
 
  class AttachmentURLHandler : public KMail::URLHandler {
  public:
    AttachmentURLHandler() : KMail::URLHandler() {}
    ~AttachmentURLHandler() {}
 
    bool handleClick( const KURL &, KMReaderWin * ) const;
    bool handleShiftClick( const KURL &url, KMReaderWin *window ) const;
    bool handleDrag( const KURL &url, const TQString& imagePath, KMReaderWin *window ) const;
    bool willHandleDrag( const KURL &url, const TQString& imagePath, KMReaderWin *window ) const;
    bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const;
    TQString statusBarMessage( const KURL &, KMReaderWin * ) const;
  private:
    partNode* partNodeForUrl( const KURL &url, KMReaderWin *w ) const;
    bool attachmentIsInHeader( const KURL &url ) const;
  };
 
  class ShowAuditLogURLHandler : public KMail::URLHandler {
  public:
      ShowAuditLogURLHandler() : KMail::URLHandler() {}
      ~ShowAuditLogURLHandler() {}
 
      bool handleClick( const KURL &, KMReaderWin * ) const;
      bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const;
      TQString statusBarMessage( const KURL &, KMReaderWin * ) const;
  };
 
  // Handler that prevents dragging of internal images added by KMail, such as the envelope image
  // in the enterprise header
  class InternalImageURLHandler : public KMail::URLHandler {
  public:
      InternalImageURLHandler() : KMail::URLHandler()
        {}
      ~InternalImageURLHandler()
        {}
      bool handleDrag( const KURL &url, const TQString& imagePath, KMReaderWin *window ) const;
      bool willHandleDrag( const KURL &url, const TQString& imagePath, KMReaderWin *window ) const;
      bool handleClick( const KURL &, KMReaderWin * ) const
        { return false; }
      bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const
        { return false; }
      TQString statusBarMessage( const KURL &, KMReaderWin * ) const
        { return TQString(); }
  };
 
  class FallBackURLHandler : public KMail::URLHandler {
  public:
    FallBackURLHandler() : KMail::URLHandler() {}
    ~FallBackURLHandler() {}
 
    bool handleClick( const KURL &, KMReaderWin * ) const;
    bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const;
    TQString statusBarMessage( const KURL & url, KMReaderWin * ) const {
      return url.prettyURL();
    }
  };
 
} // anon namespace
 
 
//
//
// BodyPartURLHandlerManager
//
//
 
class KMail::URLHandlerManager::BodyPartURLHandlerManager : public KMail::URLHandler {
public:
  BodyPartURLHandlerManager() : KMail::URLHandler() {}
  ~BodyPartURLHandlerManager();
 
  bool handleClick( const KURL &, KMReaderWin * ) const;
  bool handleContextMenuRequest( const KURL &, const TQPoint &, KMReaderWin * ) const;
  TQString statusBarMessage( const KURL &, KMReaderWin * ) const;
 
  void registerHandler( const Interface::BodyPartURLHandler * handler );
  void unregisterHandler( const Interface::BodyPartURLHandler * handler );
 
private:
  typedef TQValueVector<const Interface::BodyPartURLHandler*> BodyPartHandlerList;
  BodyPartHandlerList mHandlers;
};
 
KMail::URLHandlerManager::BodyPartURLHandlerManager::~BodyPartURLHandlerManager() {
  for_each( mHandlers.begin(), mHandlers.end(),
        DeleteAndSetToZero<Interface::BodyPartURLHandler>() );
}
 
void KMail::URLHandlerManager::BodyPartURLHandlerManager::registerHandler( const Interface::BodyPartURLHandler * handler ) {
  if ( !handler )
    return;
  unregisterHandler( handler ); // don't produce duplicates
  mHandlers.push_back( handler );
}
 
void KMail::URLHandlerManager::BodyPartURLHandlerManager::unregisterHandler( const Interface::BodyPartURLHandler * handler ) {
  // don't delete them, only remove them from the list!
  mHandlers.erase( remove( mHandlers.begin(), mHandlers.end(), handler ), mHandlers.end() );
}
 
static partNode * partNodeFromXKMailUrl( const KURL & url, KMReaderWin * w, TQString * path ) {
  assert( path );
 
  if ( !w || url.protocol() != "x-kmail" )
    return 0;
  const TQString urlPath = url.path();
 
  // urlPath format is: /bodypart/<random number>/<part id>/<path>
 
  kdDebug( 5006 ) << "BodyPartURLHandler: urlPath == \"" << urlPath << "\"" << endl;
  if ( !urlPath.startsWith( "/bodypart/" ) )
    return 0;
 
  const TQStringList urlParts = TQStringList::split( '/', urlPath.mid( 10 ), true );
  if ( urlParts.size() != 3 )
    return 0;
  bool ok = false;
  const int part_id = urlParts[1].toInt( &ok );
  if ( !ok )
    return 0;
  *path = KURL::decode_string( urlParts[2] );
  return w->partNodeForId( part_id );
}
 
bool KMail::URLHandlerManager::BodyPartURLHandlerManager::handleClick( const KURL & url, KMReaderWin * w ) const {
  TQString path;
  partNode * node = partNodeFromXKMailUrl( url, w, &path );
  if ( !node )
    return false;
  KMMessage *msg = w->message();
  if ( !msg ) return false;
  Callback callback( msg, w );
  KMail::PartNodeBodyPart part( *node, w->overrideCodec() );
  for ( BodyPartHandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it )
    if ( (*it)->handleClick( &part, path, callback ) )
      return true;
  return false;
}
 
bool KMail::URLHandlerManager::BodyPartURLHandlerManager::handleContextMenuRequest( const KURL & url, const TQPoint & p, KMReaderWin * w ) const {
  TQString path;
  partNode * node = partNodeFromXKMailUrl( url, w, &path );
  if ( !node )
    return false;
 
  KMail::PartNodeBodyPart part( *node, w->overrideCodec() );
  for ( BodyPartHandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it )
    if ( (*it)->handleContextMenuRequest( &part, path, p ) )
      return true;
  return false;
}
 
TQString KMail::URLHandlerManager::BodyPartURLHandlerManager::statusBarMessage( const KURL & url, KMReaderWin * w ) const {
  TQString path;
  partNode * node = partNodeFromXKMailUrl( url, w, &path );
  if ( !node )
    return TQString();
 
  KMail::PartNodeBodyPart part( *node, w->overrideCodec() );
  for ( BodyPartHandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it ) {
    const TQString msg = (*it)->statusBarMessage( &part, path );
    if ( !msg.isEmpty() )
      return msg;
  }
  return TQString();
}
 
//
//
// URLHandlerManager
//
//
 
KMail::URLHandlerManager::URLHandlerManager() {
  registerHandler( new KMailProtocolURLHandler() );
  registerHandler( new ExpandCollapseQuoteURLManager() );
  registerHandler( new SMimeURLHandler() );
  registerHandler( new MailToURLHandler() );
  registerHandler( new HtmlAnchorHandler() );
  registerHandler( new AttachmentURLHandler() );
  registerHandler( mBodyPartURLHandlerManager = new BodyPartURLHandlerManager() );
  registerHandler( new ShowAuditLogURLHandler() );
  registerHandler( new InternalImageURLHandler );
  registerHandler( new FallBackURLHandler() );
}
 
KMail::URLHandlerManager::~URLHandlerManager() {
  for_each( mHandlers.begin(), mHandlers.end(),
        DeleteAndSetToZero<URLHandler>() );
}
 
void KMail::URLHandlerManager::registerHandler( const URLHandler * handler ) {
  if ( !handler )
    return;
  unregisterHandler( handler ); // don't produce duplicates
  mHandlers.push_back( handler );
}
 
void KMail::URLHandlerManager::unregisterHandler( const URLHandler * handler ) {
  // don't delete them, only remove them from the list!
  mHandlers.erase( remove( mHandlers.begin(), mHandlers.end(), handler ), mHandlers.end() );
}
 
void KMail::URLHandlerManager::registerHandler( const Interface::BodyPartURLHandler * handler ) {
  if ( mBodyPartURLHandlerManager )
    mBodyPartURLHandlerManager->registerHandler( handler );
}
 
void KMail::URLHandlerManager::unregisterHandler( const Interface::BodyPartURLHandler * handler ) {
  if ( mBodyPartURLHandlerManager )
    mBodyPartURLHandlerManager->unregisterHandler( handler );
}
 
bool KMail::URLHandlerManager::handleClick( const KURL & url, KMReaderWin * w ) const {
  for ( HandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it )
    if ( (*it)->handleClick( url, w ) )
      return true;
  return false;
}
 
bool KMail::URLHandlerManager::handleShiftClick( const KURL &url, KMReaderWin *window ) const
{
  for ( HandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it )
    if ( (*it)->handleShiftClick( url, window ) )
      return true;
  return false;
}
 
bool KMail::URLHandlerManager::willHandleDrag( const KURL &url, const TQString& imagePath,
                                               KMReaderWin *window ) const
{
  for ( HandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it )
    if ( (*it)->willHandleDrag( url, imagePath, window ) )
      return true;
  return false;
}
 
bool KMail::URLHandlerManager::handleDrag( const KURL &url, const TQString& imagePath,
                                           KMReaderWin *window ) const
{
  for ( HandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it )
    if ( (*it)->handleDrag( url, imagePath, window ) )
      return true;
  return false;
}
 
bool KMail::URLHandlerManager::handleContextMenuRequest( const KURL & url, const TQPoint & p, KMReaderWin * w ) const {
  for ( HandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it )
    if ( (*it)->handleContextMenuRequest( url, p, w ) )
      return true;
  return false;
}
 
TQString KMail::URLHandlerManager::statusBarMessage( const KURL & url, KMReaderWin * w ) const {
  for ( HandlerList::const_iterator it = mHandlers.begin() ; it != mHandlers.end() ; ++it ) {
    const TQString msg = (*it)->statusBarMessage( url, w );
    if ( !msg.isEmpty() )
      return msg;
  }
  return TQString();
}
 
 
//
//
// URLHandler
//
//
 
// these includes are temporary and should not be needed for the code
// above this line, so they appear only here:
#include "kmmessage.h"
#include "kmreaderwin.h"
#include "partNode.h"
#include "kmmsgpart.h"
 
#include <ui/messagebox.h>
 
#include <tdelocale.h>
#include <tdeprocess.h>
#include <tdemessagebox.h>
#include <tdehtml_part.h>
 
#include <tqstring.h>
 
namespace {
  bool KMailProtocolURLHandler::handleClick( const KURL & url, KMReaderWin * w ) const {
    if ( url.protocol() == "kmail" ) {
      if ( !w )
        return false;
 
      if ( url.path() == "showHTML" ) {
        w->setHtmlOverride( !w->htmlOverride() );
        w->update( true );
        return true;
      }
 
      if ( url.path() == "loadExternal" ) {
        w->setHtmlLoadExtOverride( !w->htmlLoadExtOverride() );
        w->update( true );
        return true;
      }
 
      if ( url.path() == "goOnline" ) {
        kmkernel->resumeNetworkJobs();
        return true;
      }
 
      if ( url.path() == "decryptMessage" ) {
        w->setDecryptMessageOverwrite( true );
        w->update( true );
        return true;
      }
 
      if ( url.path() == "showSignatureDetails" ) {
        w->setShowSignatureDetails( true );
        w->update( true );
        return true;
      }
 
      if ( url.path() == "hideSignatureDetails" ) {
        w->setShowSignatureDetails( false );
        w->update( true );
        return true;
      }
 
      if ( url.path() == "showAttachmentQuicklist" ) {
      w->saveRelativePosition();
      w->setShowAttachmentQuicklist( true );
      w->update( true );
      return true;
      }
 
      if ( url.path() == "hideAttachmentQuicklist" ) {
      w->saveRelativePosition();
      w->setShowAttachmentQuicklist( false );
      w->update( true );
      return true;
      }
 
      if ( url.path() == "showRawToltecMail" ) {
        w->saveRelativePosition();
        w->setShowRawToltecMail( true );
        w->update( true );
        return true;
      }
 
//       if ( url.path() == "startIMApp" )
//       {
//         kmkernel->imProxy()->startPreferredApp();
//         return true;
//       }
//       //FIXME: handle startIMApp urls in their own handler, or rename this one
    }
    return false;
  }
 
  TQString KMailProtocolURLHandler::statusBarMessage( const KURL & url, KMReaderWin * ) const {
    if ( url.protocol() == "kmail" )
    {
      if ( url.path() == "showHTML" )
        return i18n("Turn on HTML rendering for this message.");
      if ( url.path() == "loadExternal" )
        return i18n("Load external references from the Internet for this message.");
      if ( url.path() == "goOnline" )
        return i18n("Work online.");
      if ( url.path() == "decryptMessage" )
        return i18n("Decrypt message.");
      if ( url.path() == "showSignatureDetails" )
        return i18n("Show signature details.");
      if ( url.path() == "hideSignatureDetails" )
        return i18n("Hide signature details.");
      if ( url.path() == "hideAttachmentQuicklist" )
        return i18n( "Hide attachment list" );
      if ( url.path() == "showAttachmentQuicklist" )
        return i18n( "Show attachment list" );
    }
    return TQString() ;
  }
}
 
namespace {
 
  bool ExpandCollapseQuoteURLManager::handleClick(
      const KURL & url, KMReaderWin * w ) const
  {
    //  kmail:levelquote/?num      -> the level quote to collapse.
    //  kmail:levelquote/?-num      -> expand all levels quote.
    if ( url.protocol() == "kmail" && url.path()=="levelquote" )
    {
      TQString levelStr= url.query().mid( 1,url.query().length() );
      bool isNumber;
      int levelQuote= levelStr.toInt(&isNumber);
      if ( isNumber )
        w->slotLevelQuote( levelQuote );
      return true;
    }
    return false;
  }
  TQString ExpandCollapseQuoteURLManager::statusBarMessage(
      const KURL & url, KMReaderWin * ) const
  {
      if ( url.protocol() == "kmail" && url.path() == "levelquote" )
      {
        TQString query= url.query();
        if ( query.length()>=2 ) {
          if ( query[ 1 ] =='-'  ) {
            return i18n("Expand all quoted text.");
          }
          else {
            return i18n("Collapse quoted text.");
          }
        }
      }
      return TQString() ;
  }
 
}
 
// defined in kmreaderwin.cpp...
extern bool foundSMIMEData( const TQString aUrl, TQString & displayName,
                TQString & libName, TQString & keyId );
 
namespace {
  bool SMimeURLHandler::handleClick( const KURL & url, KMReaderWin * w ) const {
    if ( !url.hasRef() )
      return false;
    TQString displayName, libName, keyId;
    if ( !foundSMIMEData( url.path() + '#' + url.ref(), displayName, libName, keyId ) )
      return false;
    TDEProcess cmp;
    cmp << "kleopatra" << "-query" << keyId;
    if ( !cmp.start( TDEProcess::DontCare ) )
      KMessageBox::error( w, i18n("Could not start certificate manager. "
                  "Please check your installation."),
              i18n("KMail Error") );
    return true;
  }
 
  TQString SMimeURLHandler::statusBarMessage( const KURL & url, KMReaderWin * ) const {
    TQString displayName, libName, keyId;
    if ( !foundSMIMEData( url.path() + '#' + url.ref(), displayName, libName, keyId ) )
      return TQString();
    return i18n("Show certificate 0x%1").arg( keyId );
  }
}
 
namespace {
  bool HtmlAnchorHandler::handleClick( const KURL & url, KMReaderWin * w ) const {
    if ( url.hasHost() || url.path() != "/" || !url.hasRef() )
      return false;
    if ( w && !w->htmlPart()->gotoAnchor( url.ref() ) )
      static_cast<TQScrollView*>( w->htmlPart()->widget() )->ensureVisible( 0, 0 );
    return true;
  }
}
 
namespace {
  TQString MailToURLHandler::statusBarMessage( const KURL & url, KMReaderWin * ) const {
    if ( url.protocol() != "mailto" )
      return TQString();
    return KMMessage::decodeMailtoUrl( url.url() );
  }
}
 
namespace {
 
  partNode* AttachmentURLHandler::partNodeForUrl( const KURL &url, KMReaderWin *w ) const
  {
    if ( !w || !w->message() )
      return 0;
    if ( url.protocol() != "attachment" )
      return 0;
 
    bool ok;
    int nodeId = url.path().toInt( &ok );
    if ( !ok )
      return 0;
 
    partNode * node = w->partNodeForId( nodeId );
    return node;
  }
 
  bool AttachmentURLHandler::attachmentIsInHeader( const KURL &url ) const
  {
    bool inHeader = false;
    const TQString place = url.queryItem( "place" ).lower();
    if ( place != TQString() ) {
      inHeader = ( place == "header" );
    }
    return inHeader;
  }
 
  bool AttachmentURLHandler::handleClick( const KURL & url, KMReaderWin * w ) const
  {
    partNode * node = partNodeForUrl( url, w );
    if ( !node )
      return false;
 
    const bool inHeader = attachmentIsInHeader( url );
    const bool shouldShowDialog = !node->isDisplayedEmbedded() || !inHeader;
    if ( inHeader )
      w->scrollToAttachment( node );
    if ( shouldShowDialog )
      w->openAttachment( node->nodeId(), w->tempFileUrlFromPartNode( node ).path() );
    return true;
  }
 
  bool AttachmentURLHandler::handleShiftClick( const KURL &url, KMReaderWin *window ) const
  {
    partNode * node = partNodeForUrl( url, window );
    if ( !node )
      return false;
    if ( !window )
      return false;
    window->saveAttachment( window->tempFileUrlFromPartNode( node ) );
    return true;
  }
 
  bool AttachmentURLHandler::willHandleDrag( const KURL &url, const TQString& imagePath,
                                             KMReaderWin *window ) const
  {
    Q_UNUSED( imagePath );
    return partNodeForUrl( url, window ) != 0;
  }
 
  bool AttachmentURLHandler::handleDrag( const KURL &url, const TQString& imagePath,
                                         KMReaderWin *window ) const
  {
    Q_UNUSED( imagePath );
    const partNode * node = partNodeForUrl( url, window );
    if ( !node )
      return false;
 
    KURL file = window->tempFileUrlFromPartNode( node ).path();
    if ( !file.isEmpty() ) {
      TQString icon = node->msgPart().iconName( TDEIcon::Small );
      KURLDrag* urlDrag = new KURLDrag( file, window );
      if ( !icon.isEmpty() ) {
        TQPixmap iconMap( icon );
        urlDrag->setPixmap( iconMap );
      }
      urlDrag->drag();
      return true;
    }
    else {
      return false;
    }
  }
 
  bool AttachmentURLHandler::handleContextMenuRequest( const KURL & url, const TQPoint & p, KMReaderWin * w ) const
  {
    partNode * node = partNodeForUrl( url, w );
    if ( !node )
      return false;
 
    w->showAttachmentPopup( node->nodeId(), w->tempFileUrlFromPartNode( node ).path(), p );
    return true;
  }
 
  TQString AttachmentURLHandler::statusBarMessage( const KURL & url, KMReaderWin * w ) const
  {
    partNode * node = partNodeForUrl( url, w );
    if ( !node )
      return TQString();
 
    const KMMessagePart & msgPart = node->msgPart();
    TQString name = msgPart.fileName();
    if ( name.isEmpty() )
      name = msgPart.name();
    if ( !name.isEmpty() )
      return i18n( "Attachment: %1" ).arg( name );
    return i18n( "Attachment #%1 (unnamed)" ).arg( KMReaderWin::msgPartFromUrl( url ) );
  }
}
 
namespace {
  static TQString extractAuditLog( const KURL & url ) {
    if ( url.protocol() != "kmail" || url.path() != "showAuditLog" )
      return TQString();
    assert( !url.queryItem( "log" ).isEmpty() );
    return url.queryItem( "log" );
  }
 
  bool ShowAuditLogURLHandler::handleClick( const KURL & url, KMReaderWin * w ) const {
    const TQString auditLog = extractAuditLog( url );
    if ( auditLog.isEmpty() )
        return false;
    Kleo::MessageBox::auditLog( w, auditLog );
    return true;
  }
 
  bool ShowAuditLogURLHandler::handleContextMenuRequest( const KURL & url, const TQPoint &, KMReaderWin * w ) const
  {
    Q_UNUSED( w );
    // disable RMB for my own links:
    return !extractAuditLog( url ).isEmpty();
  }
 
  TQString ShowAuditLogURLHandler::statusBarMessage( const KURL & url, KMReaderWin * ) const {
    if ( extractAuditLog( url ).isEmpty() )
      return TQString();
    else
      return i18n("Show GnuPG Audit Log for this operation");
  }
}
 
namespace {
  bool InternalImageURLHandler::handleDrag( const KURL &url, const TQString& imagePath,
                                            KMReaderWin *window ) const
  {
    Q_UNUSED( window );
    Q_UNUSED( url );
    const TQString kmailImagePath = locate( "data", "kmail/pics/" );
    if ( imagePath.contains( kmailImagePath ) ) {
      // Do nothing, don't start a drag
      return true;
    }
    return false;
  }
 
  bool InternalImageURLHandler::willHandleDrag( const KURL &url, const TQString& imagePath,
                                                KMReaderWin *window ) const
  {
    Q_UNUSED( window );
    Q_UNUSED( url );
    const TQString kmailImagePath = locate( "data", "kmail/pics/" );
    return imagePath.contains( kmailImagePath );
  }
}
 
namespace {
  bool FallBackURLHandler::handleClick( const KURL & url, KMReaderWin * w ) const {
    if ( w )
      w->emitUrlClicked( url, TQt::LeftButton );
    return true;
  }
 
  bool FallBackURLHandler::handleContextMenuRequest( const KURL & url, const TQPoint & p, KMReaderWin * w ) const {
    if ( w )
      w->emitPopupMenu( url, p );
    return true;
  }
}