/**
 *
 * Copyright the original author or authors
 *
 * 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.
 */
package org.jivesoftware.smack;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNull;

import org.jivesoftware.smack.filter.StanzaFilter;
import org.jivesoftware.smack.packet.Stanza;
import org.junit.Test;

public class StanzaCollectorTest
{

    @Test
    public void verifyRollover() throws InterruptedException
    {
        TestStanzaCollector collector = new TestStanzaCollector(null, new OKEverything(), 5);

        for (int i=0; i<6; i++)
        {
            Stanza testPacket = new TestPacket(i);
            collector.processStanza(testPacket);
        }

        // Assert that '0' has rolled off
        assertEquals("1", collector.nextResultBlockForever().getStanzaId());
        assertEquals("2", collector.nextResultBlockForever().getStanzaId());
        assertEquals("3", collector.nextResultBlockForever().getStanzaId());
        assertEquals("4", collector.nextResultBlockForever().getStanzaId());
        assertEquals("5", collector.pollResult().getStanzaId());
        assertNull(collector.pollResult());

        for (int i=10; i<15; i++)
        {
            Stanza testPacket = new TestPacket(i);
            collector.processStanza(testPacket);
        }

        assertEquals("10", collector.nextResultBlockForever().getStanzaId());
        assertEquals("11", collector.nextResultBlockForever().getStanzaId());
        assertEquals("12", collector.nextResultBlockForever().getStanzaId());
        assertEquals("13", collector.nextResultBlockForever().getStanzaId());
        assertEquals("14", collector.pollResult().getStanzaId());
        assertNull(collector.pollResult());

        assertNull(collector.nextResult(1000));
    }

    /**
     * Although this doesn't guarentee anything due to the nature of threading, it can potentially
     * catch problems.
     */
    @Test
    public void verifyThreadSafety()
    {
        int insertCount = 500;
        final TestStanzaCollector collector = new TestStanzaCollector(null, new OKEverything(), insertCount);

        Thread consumer1 = new Thread(new Runnable()
        {
            @Override
            public void run()
            {
                try
                {
                    while (true)
                    {
                        try
                        {
                            Thread.sleep(3);
                        }
                        catch (InterruptedException e)
                        {
                        }
                        @SuppressWarnings("unused")
                        Stanza packet = collector.nextResultBlockForever();
//                      System.out.println(Thread.currentThread().getName() + "  packet: " + packet);
                    }
                }
                catch (InterruptedException e) {
                    throw new RuntimeException(e);
                }
            }
        });
        consumer1.setName("consumer 1");

        Thread consumer2 = new Thread(new Runnable()
        {
            @Override
            public void run()
            {
                Stanza p = null;

                do
                {
                    try
                    {
                        Thread.sleep(3);
                    }
                    catch (InterruptedException e)
                    {
                    }
                    try {
                        p = collector.nextResult(1);
                    }
                    catch (InterruptedException e) {
                        throw new RuntimeException(e);
                    }
//                  System.out.println(Thread.currentThread().getName() + "  packet: " + p);
                }
                while (p != null);
            }
        });
        consumer2.setName("consumer 2");

        Thread consumer3 = new Thread(new Runnable()
        {
            @Override
            public void run()
            {
                Stanza p = null;

                do
                {
                    try
                    {
                        Thread.sleep(3);
                    }
                    catch (InterruptedException e)
                    {
                    }
                    p = collector.pollResult();
//                  System.out.println(Thread.currentThread().getName() + "  packet: " + p);
                }
                while (p != null);
            }
        });
        consumer3.setName("consumer 3");

        consumer1.start();
        consumer2.start();
        consumer3.start();

        for(int i=0; i<insertCount; i++)
        {
            collector.processStanza(new TestPacket(i));
        }

        try
        {
            Thread.sleep(5000);
            consumer3.join();
            consumer2.join();
            consumer1.interrupt();
        }
        catch (InterruptedException e)
        {
        }
        //We cannot guarantee that this is going to pass due to the possible issue of timing between consumer 1 
        // and main, but the probability is extremely remote.
        assertNull(collector.pollResult());
    }

    static class OKEverything implements StanzaFilter
    {
        @Override
        public boolean accept(Stanza packet)
        {
            return true;
        }

    }

    static class TestStanzaCollector extends StanzaCollector 
    {
        protected TestStanzaCollector(XMPPConnection conection, StanzaFilter packetFilter, int size)
        {
            super(conection, StanzaCollector.newConfiguration().setStanzaFilter(packetFilter).setSize(size));
        }
    }

    static class TestPacket extends Stanza
    {
        public TestPacket(int i)
        {
            setStanzaId(String.valueOf(i));
        }

        @Override
        public String toXML()
        {
            return "<packetId>" + getStanzaId() + "</packetId>";
        }

        @Override
        public String toString() {
            return toXML();
        }
    }
}