using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Azimuth.SparseLinearAlgebra;
using Azimuth.DenseLinearAlgebra;
using UnitTestSharp;

namespace Azimuth.UnitTests.SparseLinearAlgebra
{
    public class CoreTransformationTests : UnitTestSharp.TestFixture
    {
        public class Turnover : UnitTestSharp.TestFixture
        {
            public void Identity()
            {
                var A = new CoreTransformation(Matrix2x2.Identity, 0);
                var B = new CoreTransformation(Matrix2x2.Identity, 1);
                var C = new CoreTransformation(Matrix2x2.Identity, 0);

                bool success = CoreTransformation.Turnover(ref A, ref B, ref C);

                Check(success);

                if (success)
                {
                    CheckEqual(new CoreTransformation(Matrix2x2.Identity, 1), A);
                    CheckEqual(new CoreTransformation(Matrix2x2.Identity, 0), B);
                    CheckEqual(new CoreTransformation(Matrix2x2.Identity, 1), C);
                }
            }
        }

        public class Descend : UnitTestSharp.TestFixture
        {
            public void LeadingZero()
            {
                var row = new DenseVector(new Scalar[] { 1, 2, 3, 4, 5, 6, 7, });
                var coreTransform = CoreTransformation.Descend(ref row, 0, new Matrix2x2(0, 10, 20, 30));

                var expected = new CoreTransformation(new Matrix2x2(0, 1, 1, 0), 0);

                CheckEqual(expected, coreTransform);
                CheckEqual(new DenseVector(new Scalar[] { 1, 2, 3, 4, 5, 6, 7, }), row);
            }

            [IgnoreTest]
            public void Identity()
            {
                var row = new DenseVector(new Scalar[] { 1, 2, 3, 4, 5, 6, 7, });
                var coreTransform = CoreTransformation.Descend(ref row, 0, Matrix2x2.Identity);

                // I have no idea what the values should be here
            }

            public void Triangular()
            {
                var row = new DenseVector(new Scalar[] { 1, 2, 3, 4, 5, 6, 7, });
                var coreTransform = CoreTransformation.Descend(ref row, 0, new Matrix2x2(1, 0, 2, 1));

                var expected = new CoreTransformation(new Matrix2x2(0, 1, -2, 1), 0);

                CheckEqual(expected, coreTransform);
                CheckEqual(new DenseVector(new Scalar[] { 1, 2, -6, -8, -10, -12, -14, }), row);
            }

            public void Full()
            {
                var row = new DenseVector(new Scalar[] { 1, 2, 3, 4, 5, 6, 7, });
                var coreTransform = CoreTransformation.Descend(ref row, 0, new Matrix2x2(1, 2, 3, 4));

                var expected = new CoreTransformation(new Matrix2x2(0, 1, -3, 1), 0);

                CheckEqual(expected, coreTransform);
                CheckEqual(new DenseVector(new Scalar[] { 1, 2, -9, -12, -15, -18, -21, }), row);
            }
        }
    }
}