/*
    This file is part of Magnum.

    Copyright © 2010, 2011, 2012, 2013, 2014, 2015
              Vladimír Vondruš <mosra@centrum.cz>

    Permission is hereby granted, free of charge, to any person obtaining a
    copy of this software and associated documentation files (the "Software"),
    to deal in the Software without restriction, including without limitation
    the rights to use, copy, modify, merge, publish, distribute, sublicense,
    and/or sell copies of the Software, and to permit persons to whom the
    Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
    DEALINGS IN THE SOFTWARE.
*/

#include <Corrade/TestSuite/Tester.h>

#include "Magnum/Math/Algorithms/Svd.h"

namespace Magnum { namespace Math { namespace Algorithms { namespace Test {

struct SvdTest: Corrade::TestSuite::Tester {
    explicit SvdTest();

    void testDouble();
    void testFloat();
};

#ifndef MAGNUM_TARGET_GLES
typedef RectangularMatrix<5, 8, Double> Matrix5x8d;
typedef Matrix<8, Double> Matrix8d;
typedef Matrix<5, Double> Matrix5d;
typedef Vector<8, Double> Vector8d;
typedef Vector<5, Double> Vector5d;
#endif

typedef RectangularMatrix<5, 8, Float> Matrix5x8f;
typedef Matrix<8, Float> Matrix8f;
typedef Matrix<5, Float> Matrix5f;
typedef Vector<8, Float> Vector8f;
typedef Vector<5, Float> Vector5f;

#ifndef MAGNUM_TARGET_GLES
constexpr static Matrix5x8d ad(
    Vector8d(22.0, 14.0,  -1.0, -3.0,  9.0,  9.0,  2.0,  4.0),
    Vector8d(10.0,  7.0,  13.0, -2.0,  8.0,  1.0, -6.0,  5.0),
    Vector8d( 2.0, 10.0,  -1.0, 13.0,  1.0, -7.0,  6.0,  0.0),
    Vector8d( 3.0,  0.0, -11.0, -2.0, -2.0,  5.0,  5.0, -2.0),
    Vector8d( 7.0,  8.0,   3.0,  4.0,  4.0, -1.0,  1.0,  2.0)
);
static const Vector5d expectedd(std::sqrt(1248.0), 0.0, 20.0, std::sqrt(384.0), 0.0);
#endif

constexpr static Matrix5x8f af(
    Vector8f(22.0f, 14.0f,  -1.0f, -3.0f,  9.0f,  9.0f,  2.0f,  4.0f),
    Vector8f(10.0f,  7.0f,  13.0f, -2.0f,  8.0f,  1.0f, -6.0f,  5.0f),
    Vector8f( 2.0f, 10.0f,  -1.0f, 13.0f,  1.0f, -7.0f,  6.0f,  0.0f),
    Vector8f( 3.0f,  0.0f, -11.0f, -2.0f, -2.0f,  5.0f,  5.0f, -2.0f),
    Vector8f( 7.0f,  8.0f,   3.0f,  4.0f,  4.0f, -1.0f,  1.0f,  2.0f)
);
static const Vector5f expectedf(std::sqrt(1248.0f), 0.0f, 20.0f, std::sqrt(384.0f), 0.0f);

SvdTest::SvdTest() {
    addTests({&SvdTest::testDouble,
              &SvdTest::testFloat});
}

void SvdTest::testDouble() {
    #ifndef MAGNUM_TARGET_GLES
    Matrix5x8d u;
    Vector5d w;
    Matrix5d v;
    std::tie(u, w, v) = Algorithms::svd(ad);

    /* Test composition */
    Matrix8d u2(u[0], u[1], u[2], u[3], u[4], Vector8d(), Vector8d(), Vector8d());
    Matrix5x8d w2 = Matrix5x8d::fromDiagonal(w);
    CORRADE_COMPARE(u2*w2*v.transposed(), ad);

    /* Test that V is unitary */
    CORRADE_COMPARE(v*v.transposed(), Matrix5d(Matrix5d::Identity));
    CORRADE_COMPARE(v.transposed()*v, Matrix5d(Matrix5d::Identity));

    /* Test W */
    CORRADE_COMPARE(w, expectedd);
    #else
    CORRADE_SKIP("Double precision is not supported when targeting OpenGL ES.");
    #endif
}

void SvdTest::testFloat() {
    Matrix5x8f u;
    Vector5f w;
    Matrix5f v;
    std::tie(u, w, v) = Algorithms::svd(af);

    /* Test composition (single precision is not enough, test for similarity) */
    Matrix8f u2(u[0], u[1], u[2], u[3], u[4], Vector8f(), Vector8f(), Vector8f());
    Matrix5x8f w2 = Matrix5x8f::fromDiagonal(w);
    CORRADE_VERIFY(Math::abs((u2*w2*v.transposed()-af).toVector()).max() < 1.0e-5f);

    /* Test that V is unitary */
    CORRADE_COMPARE(v*v.transposed(), Matrix5f(Matrix5f::Identity));
    CORRADE_COMPARE(v.transposed()*v, Matrix5f(Matrix5f::Identity));

    /* Test W (single precision is not enough, test for similarity) */
    CORRADE_VERIFY(Math::abs(w-expectedf).max() < 1.0e-5f);
}

}}}}

CORRADE_TEST_MAIN(Magnum::Math::Algorithms::Test::SvdTest)