/*
 * QUANTCONNECT.COM - Democratizing Finance, Empowering Individuals.
 * Lean Algorithmic Trading Engine v2.0. Copyright 2014 QuantConnect Corporation.
 *
 * 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.
*/

using System;
using NUnit.Framework;
using QuantConnect.Indicators;

namespace QuantConnect.Tests.Indicators
{
    [TestFixture]
    public class RelativeStrengthIndexTests : CommonIndicatorTests<IndicatorDataPoint>
    {
        protected override IndicatorBase<IndicatorDataPoint> CreateIndicator()
        {
            return new RelativeStrengthIndex(14);
        }

        protected override string TestFileName => "spy_with_indicators.txt";

        protected override string TestColumnName => "RSI 14 Wilder";

        [Test]
        public void ComparesAgainstExternalDataSma()
        {
            var rsiSimple = new RelativeStrengthIndex("rsi", 14, MovingAverageType.Simple);
            TestHelper.TestIndicator(rsiSimple, "RSI 14");
        }

        [Test]
        public override void ResetsProperly()
        {
            var rsi = new RelativeStrengthIndex(2);
            rsi.Update(DateTime.Today, 1m);
            rsi.Update(DateTime.Today.AddSeconds(1), 2m);
            Assert.IsFalse(rsi.IsReady);

            rsi.Reset();
            TestHelper.AssertIndicatorIsInDefaultState(rsi);
            TestHelper.AssertIndicatorIsInDefaultState(rsi.AverageGain);
            TestHelper.AssertIndicatorIsInDefaultState(rsi.AverageLoss);
        }

        [Test]
        public void DoesNotThrowDivisionByZero()
        {
            var rsi = new RelativeStrengthIndex(14, MovingAverageType.DoubleExponential);

            rsi.Update(DateTime.UtcNow, 101m);
            rsi.Update(DateTime.UtcNow, 103m);

            for (var i = 0; i < 500; i++)
            {
                rsi.Update(DateTime.UtcNow, 102m);

                // validate the expected range
                Assert.That(rsi >= 0 && rsi <= 100);
            }
        }
    }
}