/*
 * 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.
 */

using System;
using System.Threading;
using Apache.NMS.ActiveMQ.Util;
using Apache.NMS.Test;
using NUnit.Framework;

namespace Apache.NMS.ActiveMQ.Test
{
    [TestFixture]
    public class MemoryUsageTest : NMSTestSupport
    {

        [Test]
        public void TestConstructors()
        {
            MemoryUsage usage = new MemoryUsage();

            Assert.That(usage.Limit == 0);
            Assert.That(usage.Usage == 0);

            usage = new MemoryUsage(1024);

            Assert.That(usage.Limit == 1024);
            Assert.That(usage.Usage == 0);
        }

        [Test]
        public void TestUsage()
        {
            MemoryUsage usage1 = new MemoryUsage( 2048 );

            Assert.That( !usage1.IsFull() );
            Assert.That( usage1.Usage == 0 );

            usage1.IncreaseUsage( 1024 );

            Assert.That( !usage1.IsFull() );
            Assert.That( usage1.Usage == 1024 );

            usage1.DecreaseUsage( 512 );

            Assert.That( !usage1.IsFull() );
            Assert.That( usage1.Usage == 512 );

            usage1.Usage = 2048;

            Assert.That( usage1.IsFull() );
            Assert.That( usage1.Usage == 2048 );

            usage1.IncreaseUsage( 1024 );
            Assert.That( usage1.IsFull() );
            Assert.That( usage1.Usage == 3072 );
        }

        [Test]
        public void TestTimedWait()
        {
            MemoryUsage usage = new MemoryUsage( 2048 );
            usage.IncreaseUsage( 5072 );

            DateTime start = DateTime.Now;

            usage.WaitForSpace( TimeSpan.FromMilliseconds(150) );

            DateTime end = DateTime.Now;

            TimeSpan timePassed = end - start;

            Assert.That( timePassed.TotalMilliseconds >= 125 );
        }

        [Test]
        public void TestWait()
        {
            MemoryUsage usage = new MemoryUsage( 2048 );
            usage.IncreaseUsage( 5072 );

            Thread thread1 = new Thread(delegate ()
            {
                Thread.Sleep( 100 );
                usage.DecreaseUsage( usage.Usage );
            });

            thread1.Start();

            usage.WaitForSpace();
            Assert.That( usage.Usage == 0 );

            thread1.Join();
        }
    }
}