using NUnit.Framework;
using FluentAssertions;

using MoonTools.Curve;
using System;
using System.Numerics;

namespace Tests
{
    public class QuadraticBezierCurve3DMathTests
    {
        [Test]
        public void Point()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            QuadraticBezierCurve3D.Point(p0, p1, p2, 0).Should().BeEquivalentTo(p0);
            QuadraticBezierCurve3D.Point(p0, p1, p2, 0.25f).Should().BeEquivalentTo(new Vector3(-1.25f, -3.5f, -0.5625f));
            QuadraticBezierCurve3D.Point(p0, p1, p2, 0.75f).Should().BeEquivalentTo(new Vector3(2.75f, 0.5f, 0.9375f));
            QuadraticBezierCurve3D.Point(p0, p1, p2, 1).Should().BeEquivalentTo(p2);

            Action invalidTime = () => QuadraticBezierCurve3D.Point(p0, p1, p2, 1.5f);
            invalidTime.Should().Throw<ArgumentException>();
        }

        [Test]
        public void PointNormalized()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            QuadraticBezierCurve3D.Point(p0, p1, p2, 15, 15, 17).Should().BeEquivalentTo(p0);
            QuadraticBezierCurve3D.Point(p0, p1, p2, 2, 1, 5).Should().BeEquivalentTo(new Vector3(-1.25f, -3.5f, -0.5625f));
            QuadraticBezierCurve3D.Point(p0, p1, p2, 8, 2, 10).Should().BeEquivalentTo(new Vector3(2.75f, 0.5f, 0.9375f));
            QuadraticBezierCurve3D.Point(p0, p1, p2, 1, -8, 1).Should().BeEquivalentTo(p2);

            Action invalidTime = () => QuadraticBezierCurve3D.Point(p0, p1, p2, 15, 2, 5);
            invalidTime.Should().Throw<ArgumentException>();
        }

        [Test]
        public void Velocity()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            QuadraticBezierCurve3D.Velocity(p0, p1, p2, 0.25f).Should().BeEquivalentTo(new Vector3(10f, 3.9999998f, 7.5f));
            QuadraticBezierCurve3D.Velocity(p0, p1, p2, 0.75f).Should().BeEquivalentTo(new Vector3(6, 12, -1.5f));

            Action invalidTime = () => QuadraticBezierCurve3D.Velocity(p0, p1, p2, 1.5f);
            invalidTime.Should().Throw<ArgumentException>();
        }

        [Test]
        public void VelocityNormalized()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            QuadraticBezierCurve3D.Velocity(p0, p1, p2, 2, 1, 5).Should().BeEquivalentTo(new Vector3(10f, 3.9999998f, 7.5f));
            QuadraticBezierCurve3D.Velocity(p0, p1, p2, 8, 2, 10).Should().BeEquivalentTo(new Vector3(6, 12, -1.5f));

            Action invalidTime = () => QuadraticBezierCurve3D.Velocity(p0, p1, p1, 15, 2, 5);
            invalidTime.Should().Throw<ArgumentException>();
        }
    }

    public class QuadraticBezierCurve3DStructTests
    {
        [Test]
        public void Point()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            var myCurve = new QuadraticBezierCurve3D(p0, p1, p2);

            myCurve.Point(0).Should().BeEquivalentTo(p0);
            myCurve.Point(0.25f).Should().BeEquivalentTo(new Vector3(-1.25f, -3.5f, -0.5625f));
            myCurve.Point(0.75f).Should().BeEquivalentTo(new Vector3(2.75f, 0.5f, 0.9375f));
            myCurve.Point(1).Should().BeEquivalentTo(p2);

            myCurve.Invoking(x => x.Point(1.5f)).Should().Throw<ArgumentException>();
        }

        [Test]
        public void PointNormalized()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            var myCurve = new QuadraticBezierCurve3D(p0, p1, p2);

            myCurve.Point(15, 15, 17).Should().BeEquivalentTo(p0);
            myCurve.Point(2, 1, 5).Should().BeEquivalentTo(new Vector3(-1.25f, -3.5f, -0.5625f));
            myCurve.Point(8, 2, 10).Should().BeEquivalentTo(new Vector3(2.75f, 0.5f, 0.9375f));
            myCurve.Point(1, -8, 1).Should().BeEquivalentTo(p2);

            myCurve.Invoking(x => x.Point(15, 2, 5)).Should().Throw<ArgumentException>();
        }

        [Test]
        public void Velocity()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            var myCurve = new QuadraticBezierCurve3D(p0, p1, p2);

            myCurve.Velocity(0.25f).Should().BeEquivalentTo(new Vector3(10f, 3.9999998f, 7.5f));
            myCurve.Velocity(0.75f).Should().BeEquivalentTo(new Vector3(6, 12, -1.5f));

            myCurve.Invoking(x => x.Velocity(1.5f)).Should().Throw<ArgumentException>();
        }

        [Test]
        public void VelocityNormalized()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            var myCurve = new QuadraticBezierCurve3D(p0, p1, p2);

            myCurve.Velocity(2, 1, 5).Should().BeEquivalentTo(new Vector3(10f, 3.9999998f, 7.5f));
            myCurve.Velocity(8, 2, 10).Should().BeEquivalentTo(new Vector3(6, 12, -1.5f));

            myCurve.Invoking(x => x.Velocity(15, 2, 5)).Should().Throw<ArgumentException>();
        }

        [Test]
        public void AsCubic()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            var myCurve = new QuadraticBezierCurve3D(p0, p1, p2);
            var myCubicCurve = myCurve.AsCubic();

            myCurve.Point(0f).Should().BeEquivalentTo(myCubicCurve.Point(0f));
            myCurve.Point(0.25f).Should().BeEquivalentTo(myCubicCurve.Point(0.25f));
            myCurve.Point(0.75f).Should().BeEquivalentTo(myCubicCurve.Point(0.75f));
            myCurve.Point(1f).Should().BeEquivalentTo(myCubicCurve.Point(1f));
        }

        [Test]
        public void Equals()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            var myCurve = new QuadraticBezierCurve3D(p0, p1, p2);
            var otherCurve = new QuadraticBezierCurve3D(p0, p1, p2);

            (myCurve == otherCurve).Should().BeTrue();
        }

        [Test]
        public void NotEquals()
        {
            var p0 = new Vector3(-4, -4, -3);
            var p1 = new Vector3(2, -4, 3);
            var p2 = new Vector3(4, 4, 0);

            var myCurve = new QuadraticBezierCurve3D(p0, p1, p2);
            var otherCurve = new QuadraticBezierCurve3D(new Vector3(0, -4, -3), p1, p2);

            (myCurve != otherCurve).Should().BeTrue();
        }
    }
}