/*
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 *
*/

#if NET_4_0 || MONO_3_5 || MONO_4_0

using System;
using System.Linq;
using System.Threading;
using NUnit.Framework;
using log4net;
using log4net.Appender;
using log4net.Config;
using log4net.Core;
using log4net.Layout;
using log4net.Repository;

namespace log4net.Tests.Appender
{
    [TestFixture]
    public class MemoryAppenderTest
    {
        private static int cThreadsRunning;
        private const int cThreadsMax = 10;
        private const int cLogEntriesPerThread = 100;
        private const long cEventsExpected = cLogEntriesPerThread * cThreadsMax;

        [Test]
        public void TestThreadSafety()
        {
            ILoggerRepository rep = LogManager.CreateRepository(Guid.NewGuid().ToString());
            var memoryAppender = new MemoryAppender();
            var patternLayout = new PatternLayout();
            memoryAppender.Layout = patternLayout;
            memoryAppender.ActivateOptions();
            BasicConfigurator.Configure(rep, memoryAppender);

            cThreadsRunning = cThreadsMax;
            var threads = Enumerable.Range(0, cThreadsMax)
                .Select(i => new Thread(LogMessages(rep.Name)))
                .ToList();

            foreach (var thread in threads)
            {
                thread.Start();
            }

            long cEventsRead = 0;
            while (cThreadsRunning > 0)
            {
                var events = memoryAppender.PopAllEvents();
                cEventsRead += events.Length;
            }
            foreach (var thread in threads)
            {
                thread.Join();
            }
	    cEventsRead += memoryAppender.PopAllEvents().Length;
            Assert.AreEqual(cEventsExpected, cEventsRead, "Log events were lost.");
        }

        private static ThreadStart LogMessages(string repository)
        {
	    return () => {
		var logger = LogManager.GetLogger(repository, "LoggerThread");
		for (var i = 0; i < cLogEntriesPerThread; i++)
		{
		    logger.InfoFormat("Logging message {0}", i);
		}
		Interlocked.Decrement(ref cThreadsRunning);
	    };
	}
    }
}
#endif