package com.erggroup.mass.ant;

import java.io.File;
import java.util.ArrayList;
import java.util.Iterator;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.FileScanner;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.taskdefs.Jar;
import org.apache.tools.ant.taskdefs.Manifest;
import org.apache.tools.ant.taskdefs.ManifestException;
import org.apache.tools.ant.types.FileSet;


public class ManifestElement implements JatsElement
{
	private static final String MANIFEST_NAME = "META-INF/MANIFEST.MF";
	
	static final String TASK_NAME = "manifest";
	
	private String implementationVersion;
	
	private ArrayList filesets = new ArrayList();

	public FileSet createFileset()
	{
		 FileSet fileset = new FileSet();
		filesets.add( fileset );
		 return fileset;
	}
	
	public void setImplementationVersion(String value)
	{
		this.implementationVersion = value;
	}	
	
	public void execute(Jats parent)
	{
		if ( filesets.size() == 0 ) 
		{
			throw new BuildException("At least one fileset must be provided");	
		}
		
		for ( Iterator i=filesets.iterator(); i.hasNext(); )
		{
			FileSet fileset = (FileSet)i.next();
			FileScanner scanner = fileset.getDirectoryScanner( parent.getProject() );
			String[] files = scanner.getIncludedFiles();
			File basedir = scanner.getBasedir();
			for ( int j=0; j<files.length; j++ )
			{
				//log( "Updating manifest for file " + files[j], Project.MSG_VERBOSE );
				File file = new File( basedir, files[j] );
				updateManifest( file, parent.getProject() );
			}
		}
	}
	
	protected void updateManifest( File jarFile, Project p )
	{
		Jar jar = new Jar();	
		jar.setDestFile(jarFile);
		jar.setUpdate(true);		
		
		try
		{
			Manifest newManifest = new Manifest();
			if ( implementationVersion != null )
				newManifest.addConfiguredAttribute( new Manifest.Attribute( "Implementation-Version", implementationVersion ) );
			newManifest.addConfiguredAttribute( new Manifest.Attribute( "Implementation-Vendor", "ERG Transit Systems" ) );				
			jar.addConfiguredManifest(newManifest);
		}
		catch ( ManifestException x )
		{
			throw new BuildException("Manifest creation error.",x);			
		}
		jar.setProject(p);
		jar.execute();
	}

	public String getElementType()
	{
		return TASK_NAME;
	}

}