extends AbstractRewritePomsPhase
{
    /**
     * SCM URL translators mapped by provider name.
     */
    private Map<String, ScmTranslator> scmTranslators;

    protected void transformScm( MavenProject project, Element rootElement, Namespace namespace,
                                 ReleaseDescriptor releaseDescriptor, String projectId, ScmRepository scmRepository,
                                 ReleaseResult result, String commonBasedir )
    throws ReleaseExecutionException
    {
        // If SCM is null in original model, it is inherited, no mods needed
        if ( project.getScm() != null )
        {
            Element scmRoot = rootElement.getChild( "scm", namespace );
            if ( scmRoot != null )
            {
                Scm scm = buildScm( project );
                releaseDescriptor.mapOriginalScmInfo( projectId, scm );

                try
                {
                    translateScm( project, releaseDescriptor, scmRoot, namespace, scmRepository, result, commonBasedir );
                }
                catch ( IOException e )
                {
                    throw new ReleaseExecutionException( e.getMessage(), e );
                }
            }
            else
            {
                releaseDescriptor.mapOriginalScmInfo( projectId, null );

                MavenProject parent = project.getParent();
                if ( parent != null )
                {
                    // If the SCM element is not present, only add it if the parent was not mapped (ie, it's external to
                    // the release process and so has not been modified, so the values will not be correct on the tag),
                    String parentId = ArtifactUtils.versionlessKey( parent.getGroupId(), parent.getArtifactId() );
                    if ( !releaseDescriptor.getOriginalScmInfo().containsKey( parentId ) )
                    {
                        // we need to add it, since it has changed from the inherited value
                        scmRoot = new Element( "scm" );
                        scmRoot.addContent( "\n  " );

                        try
                        {
                            if ( translateScm( project, releaseDescriptor, scmRoot, namespace, scmRepository, result,
                                               commonBasedir ) )
                            {
                                rootElement.addContent( "\n  " ).addContent( scmRoot ).addContent( "\n" );
                            }
                        }
                        catch ( IOException e )
                        {
                            throw new ReleaseExecutionException( e.getMessage(), e );
                        }
                    }
                }
            }
        }
    }

    private boolean translateScm( MavenProject project, ReleaseDescriptor releaseDescriptor, Element scmRoot,
                                  Namespace namespace, ScmRepository scmRepository, ReleaseResult relResult,
                                  String commonBasedir ) throws IOException
    {
        ScmTranslator translator = scmTranslators.get( scmRepository.getProvider() );
        boolean result = false;
        if ( translator != null )
        {
            Scm scm = project.getOriginalModel().getScm();

                String value = translator.resolveTag( tag );
                if ( value != null && !value.equals( scm.getTag() ) )
                {
                    rewriteElement( "tag", value, scmRoot, namespace );
                    result = true;
                }
            }
        }
        else
        {
            String message = "No SCM translator found - skipping rewrite";

            relResult.appendDebug( message );

            getLogger().debug( message );
        }
        return result;
    }

    protected Map<String, String> getOriginalVersionMap( ReleaseDescriptor releaseDescriptor,
                                                         List<MavenProject> reactorProjects, boolean simulate )
    {
        return releaseDescriptor.getOriginalVersions( reactorProjects );
    }

    @SuppressWarnings( "unchecked" )
    protected Map<String,String> getNextVersionMap( ReleaseDescriptor releaseDescriptor )
    {
        return releaseDescriptor.getReleaseVersions();
    }

    protected String getResolvedSnapshotVersion( String artifactVersionlessKey,
                                                 Map<String, Map<String, String>> resolvedSnapshotsMap )
    {
        Map<String, String> versionsMap = resolvedSnapshotsMap.get( artifactVersionlessKey );

        if ( versionsMap != null )
        {
            return versionsMap.get( ReleaseDescriptor.RELEASE_KEY );
        }
        else
        {
            return null;
        }
    }