using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using UnitTestSharp;
using Azimuth.Polynomials;

namespace Azimuth.UnitTests.Polynomials
{
    public class QuadraticTests : TestFixture
    {
        public void Basic()
        {
            RootList actual = Quadratic.Solve(1, 18, 17);
            RootList expected = new Scalar?[] {-17, -1};

            CheckEqual(expected, actual);
        }

        public void A0()
        {
            RootList actual = Quadratic.Solve(0, 9, 4.25);
            RootList expected = new Scalar?[] { -4.25 / 9.0 };

            CheckEqual(expected, actual);
        }

        public void B0()
        {
            RootList actual = Quadratic.Solve(9, 0, -9);
            RootList expected = new Scalar?[] { -1, 1 };

            CheckEqual(expected, actual);
        }

        public void C0()
        {
            RootList actual = Quadratic.Solve(9, 3, 0);
            RootList expected = new Scalar?[] { -1.0 / 3.0, 0 };

            CheckEqual(expected, actual);
        }

        public void AB0()
        {
            RootList actual = Quadratic.Solve(0, 0, 17);
            RootList expected = new RootList();

            CheckEqual(expected, actual);
        }

        public void AC0()
        {
            RootList actual = Quadratic.Solve(0, 10, 0);
            RootList expected = new Scalar?[] { 0 };

            CheckEqual(expected, actual);
        }

        public void BC0()
        {
            RootList actual = Quadratic.Solve(10, 0, 0);
            RootList expected = new Scalar?[] { 0, 0 };

            CheckEqual(expected, actual);
        }

        public void ABC0()
        {
            RootList actual = Quadratic.Solve(0, 0, 0);
            RootList expected = new Scalar?[] { Scalar.PositiveInfinity };

            CheckEqual(expected, actual);
        }

        public void Discriminant0()
        {
            RootList actual = Quadratic.Solve(2, 4, 2);
            RootList expected = new Scalar?[] { -1, -1 };

            CheckEqual(expected, actual);
        }

        public void Multiplicity_2()
        {
            RootList actual = Quadratic.Solve(1, -2, 1);
            RootList expected = new Scalar?[] { 1, 1 };

            CheckEqual(expected, actual);
        }

        public void RootsOrderedProperly_Pos()
        {
            RootList actual = Quadratic.Solve(1, 0, -4);
            RootList expected = new Scalar?[] { -2, 2 };

            CheckEqual(expected, actual);
        }

        public void RootsOrderedProperly_Neg()
        {
            RootList actual = Quadratic.Solve(-1, 0, 4);
            RootList expected = new Scalar?[] { -2, 2 };

            CheckEqual(expected, actual);
        }

        public void QWouldBe0()
        {
            RootList actual = Quadratic.Solve(10, 5, 0);
            RootList expected = new Scalar?[] { -1.0 / 2.0, 0 };

            CheckEqual(expected, actual);
        }
    }
}