package org.codehaus.plexus.util;

/*
 * Copyright The Codehaus Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.util.Collection;
import java.util.Iterator;
import java.util.Vector;
import java.util.logging.Logger;

/**
 * Manages  a number of test threads, which notify this manager when they have
 * completed. Allows TestCases to easily start and manage multiple test threads.
 *
 * <p>Created on 9/06/2003</p>
 *
 * @author <a href="mailto:bert@tuaworks.co.nz">Bert van Brakel</a>
 * @version $Revision: 8010 $
 *
 */
public class TestThreadManager
{
    //~ Instance fields ----------------------------------------------------------------------------

    /** Test threads which have completed running */
    private Collection runThreads = new Vector();
    /** Test threads still needing to be run, or are currently running*/
    private Collection toRunThreads = new Vector();
    private Logger logger = null;
    /** Any test threads which failed */
    private Vector failedThreads = new Vector();

    /**The object to notify when all the test threads have complleted. Clients use this
     * to lock on (wait) while waiting for the tests to complete*/
    private Object notify = null;

    //~ Constructors -------------------------------------------------------------------------------

    public TestThreadManager( Object notify )
    {
        super();
        this.notify = notify;
    }

    //~ Methods ------------------------------------------------------------------------------------

    /**
     * @return
     */
    public Collection getRunThreads()
    {
        return runThreads;
    }

    public void runTestThreads()
    {
        failedThreads.clear();
        //use an array as the tests may run very quickly
        //and modify the toRunThreads vector and hence
        //cause a Concurrent ModificationException on an
        //iterator
        Object[] threads = toRunThreads.toArray();
        for ( int i = 0; i < threads.length; i++ )
        {
            //System.out.println("Starting thread " + i +" ..." );
            ( (AbstractTestThread) threads[i] ).start();
        }
    }

    public Collection getFailedTests()
    {
        return failedThreads;
    }

    /**
     * Return the object which threads can wait on to be notified
     * when all the test threads have completed running
     *
     * @return
     */
    public Object getNotifyObject()
    {
        return notify;
    }


    public boolean hasFailedThreads()
    {
        if ( failedThreads.size() == 0 )
        {
            return false;
        }
        else
            return true;
    }

    /**
     * Determine if any threads are still running!
     *
     * @return DOCUMENT ME!
     */
    public boolean isStillRunningThreads()
    {
        return !toRunThreads.isEmpty();
    }

    /**
     * @return
     */
    public Collection getToRunThreads()
    {
        return toRunThreads;
    }

    /**
     * DOCUMENT ME!
     */
    public void clear()
    {
        toRunThreads.clear();
        runThreads.clear();
        failedThreads.clear();
    }

    /* (non-Javadoc)
    * @see java.util.Collection#remove(java.lang.Object)
    */
    public synchronized void completed( AbstractTestThread thread )
    {
        toRunThreads.remove( thread );
        runThreads.add( thread );
        if ( thread.hasFailed() )
        {
            failedThreads.add( thread );
        }
        //wakeup thread which is waiting for the threads to complete
        //execution
        if ( toRunThreads.isEmpty() )
        {
            synchronized ( notify )
            {
                notify.notify();
            }
        }
    }

    /**
     * Overide this to add your own stuff. Called after
     * <code>registerThread(Object)</code>
     *
     * @param thread DOCUMENT ME!
     */
    public void doRegisterThread( AbstractTestThread thread )
    {
    }

    public final void registerThread( AbstractTestThread thread )
    {
        thread.setThreadRegistry( this );
        if ( toRunThreads.contains( thread ) == false )
        {
            toRunThreads.add( thread );
            doRegisterThread( thread );
        }

    }

    /**
     * Put all the runThreads back in the que to be run again and
     * clear the failedTest collection
     */
    public void reset()
    {
        toRunThreads.clear();
        Iterator iter = runThreads.iterator();
        while ( iter.hasNext() )
        {
            AbstractTestThread test = (AbstractTestThread) iter.next();
            test.reset();
            registerThread( test );
        }

        runThreads.clear();
        failedThreads.clear();
    }
}