using System;
using Upsilon.BaseTypes.UserData;
using Upsilon.Evaluator;
using Xunit;
// ReSharper disable UnusedMember.Local
// ReSharper disable ClassNeverInstantiated.Global

namespace UpsilonTests
{
    public class UserDataOperatorTests : TestClass, IClassFixture<UserDataOperatorTests.UserDataOperatorTestsFixture>
    {
        public class UserDataOperatorTestsFixture : IDisposable
        {
            public UserDataOperatorTestsFixture()
            {
                UserDataTypeHandler.LoadType<UserDataHelper>();
            }

            public void Dispose()
            {
            }
        }

#pragma warning disable 414, 649
        private class UserDataHelper
        {
            public UserDataHelper(double value)
            {
                Value = value;
            }

            public double Value { get; }

            public static UserDataHelper operator +(UserDataHelper a, UserDataHelper b)
            {
                return new UserDataHelper(a.Value + b.Value);
            }

            public static UserDataHelper operator +(UserDataHelper a, double b)
            {
                return new UserDataHelper(a.Value + b);
            }

            public static UserDataHelper operator -(UserDataHelper a, UserDataHelper b)
            {
                return new UserDataHelper(a.Value - b.Value);
            }

            public static UserDataHelper operator -(UserDataHelper a)
            {
                return new UserDataHelper(-a.Value);
            }

            public static UserDataHelper operator *(UserDataHelper a, UserDataHelper b)
            {
                return new UserDataHelper(a.Value * b.Value);
            }

            public static UserDataHelper operator /(UserDataHelper a, UserDataHelper b)
            {
                return new UserDataHelper(a.Value / b.Value);
            }

        }
#pragma warning restore 414, 649


        [Fact]
        public void TestAddition()
        {
            const string input = @"
function add(o1, o2)
    return o1 + o2
end
";
            var script = new Script(input, BoundScope, StaticScope);
            Assert.Empty(script.Diagnostics.Messages);
            var o1     = new UserDataHelper(100);
            var o2     = new UserDataHelper(215);
            var result = script.EvaluateFunction<UserDataHelper>("add", new[] {o1, o2});
            Assert.Empty(script.Diagnostics.Messages);
            Assert.Equal(315, result.Value);
        }

        [Fact]
        public void TestAdditionOverloading()
        {
            const string input = @"
function add(o1, o2)
    return o1 + o2
end
";
            var script = new Script(input, BoundScope, StaticScope);
            Assert.Empty(script.Diagnostics.Messages);
            var o1     = new UserDataHelper(100);
            const double o2 = 1.5;
            var result = script.EvaluateFunction<UserDataHelper>("add", new object[] {o1, o2});
            Assert.Empty(script.Diagnostics.Messages);
            Assert.Equal(101.5, result.Value);
        }

        [Fact]
        public void TestSubtraction()
        {
            const string input = @"
function subtract(o1, o2)
    return o1 - o2
end
";
            var script = new Script(input, BoundScope, StaticScope);
            Assert.Empty(script.Diagnostics.Messages);
            var          o1     = new UserDataHelper(100);
            var o2 = new UserDataHelper(1.5);
            var          result = script.EvaluateFunction<UserDataHelper>("subtract", new object[] {o1, o2});
            Assert.Empty(script.Diagnostics.Messages);
            Assert.Equal(98.5, result.Value);
        }

        [Fact]
        public void TestMultiplication()
        {
            const string input = @"
function multiply(o1, o2)
    return o1 * o2
end
";
            var script = new Script(input, BoundScope, StaticScope);
            Assert.Empty(script.Diagnostics.Messages);
            var          o1     = new UserDataHelper(100);
            var o2     = new UserDataHelper(4);
            var          result = script.EvaluateFunction<UserDataHelper>("multiply", new object[] {o1, o2});
            Assert.Empty(script.Diagnostics.Messages);
            Assert.Equal(400, result.Value);
        }

        [Fact]
        public void TestDivision()
        {
            const string input = @"
function divide(o1, o2)
    return o1 / o2
end
";
            var script = new Script(input, BoundScope, StaticScope);
            Assert.Empty(script.Diagnostics.Messages);
            var          o1     = new UserDataHelper(100);
            var o2     = new UserDataHelper(10);
            var          result = script.EvaluateFunction<UserDataHelper>("divide", new object[] {o1, o2});
            Assert.Empty(script.Diagnostics.Messages);
            Assert.Equal(10, result.Value);
        }

        [Fact]
        public void TestNegation()
        {
            const string input = @"
function negate(o1)
    return -o1
end
";
            var script = new Script(input, BoundScope, StaticScope);
            Assert.Empty(script.Diagnostics.Messages);
            var o1     = new UserDataHelper(100);
            var result = script.EvaluateFunction<UserDataHelper>("negate", new object[] {o1});
            Assert.Empty(script.Diagnostics.Messages);
            Assert.Equal(-100, result.Value);
        }

        public UserDataOperatorTests(StaticScriptFixture fix) : base(fix)
        {
        }
    }
}