/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2020 - Raw Material Software Limited

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{
namespace dsp
{

struct LinearAlgebraUnitTest  : public UnitTest
{
    LinearAlgebraUnitTest()
        : UnitTest ("Linear Algebra UnitTests", UnitTestCategories::dsp)
    {}

    struct AdditionTest
    {
        template <typename ElementType>
        static void run (LinearAlgebraUnitTest& u)
        {
            const ElementType data1[] = { 1,  2, 3,  4,  5,  6,  7,  8 };
            const ElementType data2[] = { 1, -1, 3, -1,  5, -1,  7, -1 };
            const ElementType data3[] = { 2,  1, 6,  3, 10,  5, 14,  7 };

            Matrix<ElementType> mat1 (2, 4, data1);
            Matrix<ElementType> mat2 (2, 4, data2);
            Matrix<ElementType> mat3 (2, 4, data3);

            u.expect((mat1 + mat2) == mat3);
        }
    };

    struct DifferenceTest
    {
        template <typename ElementType>
        static void run (LinearAlgebraUnitTest& u)
        {
            const ElementType data1[] = { 1,  2, 3,  4, 5,  6, 7,  8 };
            const ElementType data2[] = { 1, -1, 3, -1, 5, -1, 7, -1 };
            const ElementType data3[] = { 0,  3, 0,  5, 0,  7, 0,  9 };

            Matrix<ElementType> mat1 (2, 4, data1);
            Matrix<ElementType> mat2 (2, 4, data2);
            Matrix<ElementType> mat3 (2, 4, data3);

            u.expect((mat1 - mat2) == mat3);
        }
    };

    struct ScalarMultiplicationTest
    {
        template <typename ElementType>
        static void run (LinearAlgebraUnitTest& u)
        {
            const ElementType data1[] = { 1,  2, 3,  4, 5,  6, 7,  8 };
            const ElementType scalar = 2.0;
            const ElementType data2[] = { 2, 4, 6, 8, 10, 12, 14, 16 };

            Matrix<ElementType> x (2, 4, data1);
            Matrix<ElementType> expected (2, 4, data2);

            u.expect ((x * scalar) == expected);
        }
    };

    struct HadamardProductTest
    {
        template <typename ElementType>
        static void run (LinearAlgebraUnitTest& u)
        {
            const ElementType data1[] = { 1,  2, 3,  4,  5,  6,  7,  8 };
            const ElementType data2[] = { 1, -1, 3, -1,  5, -1,  7, -1 };
            const ElementType data3[] = { 1, -2, 9, -4, 25, -6, 49, -8 };

            Matrix<ElementType> mat1 (2, 4, data1);
            Matrix<ElementType> mat2 (2, 4, data2);
            Matrix<ElementType> mat3 (2, 4, data3);

            u.expect (Matrix<ElementType>::hadarmard (mat1, mat2) == mat3);
        }
    };

    struct MultiplicationTest
    {
        template <typename ElementType>
        static void run (LinearAlgebraUnitTest& u)
        {
            const ElementType data1[] = { 1,  2, 3,  4,  5,  6,  7,  8 };
            const ElementType data2[] = { 1, -1, 3, -1,  5, -1,  7, -1 };
            const ElementType data3[] = { 50, -10, 114, -26 };

            Matrix<ElementType> mat1 (2, 4, data1);
            Matrix<ElementType> mat2 (4, 2, data2);
            Matrix<ElementType> mat3 (2, 2, data3);

            u.expect((mat1 * mat2) == mat3);
        }
    };

    struct IdentityMatrixTest
    {
        template <typename ElementType>
        static void run (LinearAlgebraUnitTest& u)
        {
            const ElementType data1[] = { 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
            u.expect (Matrix<ElementType>::identity (4) == Matrix<ElementType> (4, 4, data1));
        }
    };

    struct SolvingTest
    {
        template <typename ElementType>
        static void run (LinearAlgebraUnitTest& u)
        {
            const ElementType data1[] = { 1, -1, 2, -2 };
            const ElementType data2[] = { -1, 0, -1, -7 };
            const ElementType data3[] = { 1, 4, 2, 1, -1, 1, 4, 3, -2, -1, 1, 1, -1, 0, 1, 4 };

            Matrix<ElementType> X (4, 1, data1);
            Matrix<ElementType> B (4, 1, data2);
            Matrix<ElementType> A (4, 4, data3);

            u.expect (A.solve (B));
            u.expect (Matrix<ElementType>::compare (X, B, (ElementType) 1e-4));
        }
    };

    template <class TheTest>
    void runTestForAllTypes (const char* unitTestName)
    {
        beginTest (unitTestName);

        TheTest::template run<float> (*this);
        TheTest::template run<double> (*this);
    }

    void runTest() override
    {
        runTestForAllTypes<AdditionTest> ("AdditionTest");
        runTestForAllTypes<DifferenceTest> ("DifferenceTest");
        runTestForAllTypes<ScalarMultiplicationTest> ("ScalarMultiplication");
        runTestForAllTypes<HadamardProductTest> ("HadamardProductTest");
        runTestForAllTypes<MultiplicationTest> ("MultiplicationTest");
        runTestForAllTypes<IdentityMatrixTest> ("IdentityMatrixTest");
        runTestForAllTypes<SolvingTest> ("SolvingTest");
    }
};

static LinearAlgebraUnitTest linearAlgebraUnitTest;

} // namespace dsp
} // namespace juce