001package votorola.s.gwt.stage.link; // Copyright 2012-2013, Michael Allan.  Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Votorola Software"), to deal in the Votorola Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicence, and/or sell copies of the Votorola Software, and to permit persons to whom the Votorola Software is furnished to do so, subject to the following conditions: The preceding copyright notice and this permission notice shall be included in all copies or substantial portions of the Votorola Software. THE VOTOROLA SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE VOTOROLA SOFTWARE OR THE USE OR OTHER DEALINGS IN THE VOTOROLA SOFTWARE.
002
003import com.google.gwt.dom.client.*;
004import com.google.gwt.user.client.Window;
005import votorola.a.diff.*;
006import votorola.a.web.gwt.*;
007import votorola.g.web.gwt.*;
008import votorola.s.gwt.stage.*;
009
010
011/** A targeter for a difference link in a link track.
012  */
013class DifferenceTargeter extends LinkTrackV.Targeter1
014{
015
016
017    /** Creates a DifferenceTargeter.
018      */
019    DifferenceTargeter( final LinkTrackV trackV, final AnchorElement diffLink )
020    {
021        trackV.super( diffLink, "difference" );
022    }
023
024
025
026   // ------------------------------------------------------------------------------------
027
028
029    /** Returns the target location for the specified difference look, or null if the
030      * current page is already at that location.
031      */
032    static final String href( final DiffLook look )
033    {
034        if( DiffLookJS.EQUATOR.equals( look, href_lookLast )) return href_hrefLast; // cached
035
036        final String key = look.key();
037        final String selectand = look.selectand();
038        final String sEffective;
039        {
040            final String s = Window.Location.getParameter( "s" );
041            if( s == null ) sEffective = "a";
042            else if( s.equals( "" )) sEffective = "b";
043            else sEffective = s;
044        }
045        String href = null;
046        final StringBuilder b = GWTX.stringBuilderClear();
047        b.append( App.getServletContextLocation() ).append( "/w/D?" );
048        final boolean alreadyAtLocation = Window.Location.getHref().startsWith( b.toString() )
049         && key.equals( Window.Location.getParameter( "k" ))
050         && selectand.equals( sEffective );
051        if( !alreadyAtLocation )
052        {
053            b.append(  "k=" ).append( key );
054            if( !"a".equals( selectand ))
055            {
056                assert "b".equals( selectand );
057                b.append( "&s" );
058            }
059            href = b.toString();
060        }
061        href_lookLast = look;
062        href_hrefLast = href;
063        return href;
064    }
065
066
067        private static DiffLook href_lookLast;
068
069
070        private static String href_hrefLast; // cached for sake of NominalDifferenceTargeter
071
072
073
074   // - T a r g e t t e r ----------------------------------------------------------------
075
076
077    @Override void retarget()
078    {
079        final DiffLook look = Stage.i().getDifference();
080        final String href;
081        if( look == null ) href = null;
082        else href = href( look );
083        setTarget( adjustedTarget( href ));
084    }
085
086
087}