/*******************************************************************************
 *
 * Copyright (c) 2010, InfraDNA, Inc.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *
 *
 *
 *
 *******************************************************************************/ 

package hudson.matrix;

import hudson.Extension;
import hudson.model.Hudson;
import org.kohsuke.stapler.DataBoundConstructor;

import java.util.List;

/**
 * {@link Axis} that selects label expressions.
 *
 * @author Kohsuke Kawaguchi
 */
public class LabelAxis extends Axis {

    @DataBoundConstructor
    public LabelAxis(String name, List<String> values) {
        super(name, values);
    }

    @Override
    public boolean isSystem() {
        return true;
    }

    @Extension
    public static class DescriptorImpl extends AxisDescriptor {

        @Override
        public String getDisplayName() {
            return Messages.LabelAxis_DisplayName();
        }

        /**
         * If there's no distributed build set up, it's pointless to provide
         * this axis.
         */
        @Override
        public boolean isInstantiable() {
            Hudson h = Hudson.getInstance();
            return !h.getNodes().isEmpty() || !h.clouds.isEmpty();
        }
    }
}