using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using NUnit.Framework;
// ReSharper disable UnusedMember.Local

namespace Chernobyl.Mathematics
{
    [TestFixture, Description("Tests for the Range type.")]
    public class RangeTests
    {
        [Test, Description("Ensures Normalize throws an argument out of range exception.")]
        [TestCaseSource(typeof(BadData), nameof(BadData.TestCases))]
        public void NormalizeThrowsArgumentOutOfRange(double value, Tuple<double, double> oldRange, Tuple<double, double> newRange)
        {
            Assert.Throws<ArgumentOutOfRangeException>(() => value.Normalize(oldRange, newRange));
        }


        [Test, Description("Ensures Normalize can scale values to the new range.")]
        [TestCaseSource(typeof(GoodData), nameof(GoodData.TestCases))]
        public double Normalize(double value, Tuple<double, double> oldRange, Tuple<double, double> newRange)
        {
            return value.Normalize(oldRange, newRange);
        }

        class BadData
        {
            public static IEnumerable TestCases
            {
                get
                {
                    // Value out of range
                    yield return new TestCaseData(9.0, Tuple.Create(10.0, 100.0), Tuple.Create(10.0, 200.0)).SetName("Value range 1");
                    yield return new TestCaseData(101.0, Tuple.Create(10.0, 100.0), Tuple.Create(10.0, 200.0)).SetName("Value range 2");

                    // Old range min greater than or equal to max
                    yield return new TestCaseData(10.0, Tuple.Create(10.0, 10.0), Tuple.Create(10.0, 200.0)).SetName("Old range 1");
                    yield return new TestCaseData(10.0, Tuple.Create(10.0, 9.0), Tuple.Create(10.0, 200.0)).SetName("Old range 2");

                    // New range min greater than or equal to max
                    yield return new TestCaseData(10.0, Tuple.Create(10.0, 100.0), Tuple.Create(10.0, 10.0)).SetName("New range 1");
                    yield return new TestCaseData(10.0, Tuple.Create(10.0, 100.0), Tuple.Create(10.0, 9.0)).SetName("New range 1");
                }
            }
        }

        class GoodData
        {
            public static IEnumerable TestCases
            {
                get
                {
                    // Scaling
                    yield return new TestCaseData(10.0, Tuple.Create(10.0, 100.0), Tuple.Create(10.0, 200.0)).Returns(10.0).SetName("Scaling 1");
                    yield return new TestCaseData(100.0, Tuple.Create(10.0, 100.0), Tuple.Create(10.0, 200.0)).Returns(200.0).SetName("Scaling 2");
                    yield return new TestCaseData(50.0, Tuple.Create(20.0, 100.0), Tuple.Create(10.0, 200.0)).Returns(81.25).SetName("Scaling 3");
                    yield return new TestCaseData(80.0, Tuple.Create(20.0, 100.0), Tuple.Create(10.0, 200.0)).Returns(152.5).SetName("Scaling 4");

                    // Shifting
                    yield return new TestCaseData(10.0, Tuple.Create(10.0, 100.0), Tuple.Create(20.0, 110.0)).Returns(20.0).SetName("Shifting 1");
                    yield return new TestCaseData(100.0, Tuple.Create(10.0, 100.0), Tuple.Create(20.0, 110.0)).Returns(110.0).SetName("Shifting 2");
                    yield return new TestCaseData(50.0, Tuple.Create(10.0, 100.0), Tuple.Create(20.0, 110.0)).Returns(60.0).SetName("Shifting 3");
                    yield return new TestCaseData(80.0, Tuple.Create(10.0, 100.0), Tuple.Create(20.0, 110.0)).Returns(90.0).SetName("Shifting 4");
                }
            }
        }
    }
}