/*
    Copyright © 2010, 2011, 2012 Vladimír Vondruš <mosra@centrum.cz>

    This file is part of Magnum.

    Magnum is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License version 3
    only, as published by the Free Software Foundation.

    Magnum is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    GNU Lesser General Public License version 3 for more details.
*/

#include <sstream>
#include <TestSuite/Tester.h>
#include <Utility/Configuration.h>

#include "Math/Vector.h"

struct Vec3 {
    float x, y, z;
};

namespace Magnum { namespace Math {

namespace Implementation {

template<> struct VectorConverter<3, float, Vec3> {
    inline static Vector<3, Float> from(const Vec3& other) {
        return {other.x, other.y, other.z};
    }

    inline static Vec3 to(const Vector<3, Float>& other) {
        return {other[0], other[1], other[2]};
    }
};

}

namespace Test {

class VectorTest: public Corrade::TestSuite::Tester {
    public:
        VectorTest();

        void construct();
        void constructFromData();
        void constructDefault();
        void constructOneValue();
        void constructOneComponent();
        void constructConversion();
        void constructCopy();

        void convert();
        void data();

        void negative();
        void addSubtract();
        void multiplyDivide();
        void multiplyDivideComponentWise();

        void compare();
        void compareComponentWise();

        void dot();
        void dotSelf();
        void length();
        void normalized();

        void sum();
        void product();
        void min();
        void minAbs();
        void max();
        void maxAbs();

        void projected();
        void projectedOntoNormalized();
        void angle();

        void debug();
        void configuration();
};

typedef Math::Rad<Float> Rad;
typedef Vector<3, Float> Vector3;
typedef Vector<4, Float> Vector4;
typedef Vector<4, Int> Vector4i;

VectorTest::VectorTest() {
    addTests({&VectorTest::construct,
              &VectorTest::constructFromData,
              &VectorTest::constructDefault,
              &VectorTest::constructOneValue,
              &VectorTest::constructOneComponent,
              &VectorTest::constructConversion,
              &VectorTest::constructCopy,

              &VectorTest::convert,
              &VectorTest::data,

              &VectorTest::negative,
              &VectorTest::addSubtract,
              &VectorTest::multiplyDivide,
              &VectorTest::multiplyDivideComponentWise,

              &VectorTest::compare,
              &VectorTest::compareComponentWise,

              &VectorTest::dot,
              &VectorTest::dotSelf,
              &VectorTest::length,
              &VectorTest::normalized,

              &VectorTest::sum,
              &VectorTest::product,
              &VectorTest::min,
              &VectorTest::minAbs,
              &VectorTest::max,
              &VectorTest::maxAbs,

              &VectorTest::projected,
              &VectorTest::projectedOntoNormalized,
              &VectorTest::angle,

              &VectorTest::debug,
              &VectorTest::configuration});
}

void VectorTest::construct() {
    constexpr Vector4 a(1.0f, 2.0f, -3.0f, 4.5f);
    CORRADE_COMPARE(a, Vector4(1.0f, 2.0f, -3.0f, 4.5f));
}

void VectorTest::constructDefault() {
    constexpr Vector4 a;
    CORRADE_COMPARE(a, Vector4(0.0f, 0.0f, 0.0f, 0.0f));
}

void VectorTest::constructFromData() {
    Float data[] = { 1.0f, 2.0f, 3.0f, 4.0f };
    CORRADE_COMPARE(Vector4::from(data), Vector4(1.0f, 2.0f, 3.0f, 4.0f));
}

void VectorTest::constructOneValue() {
    #ifndef CORRADE_GCC46_COMPATIBILITY
    constexpr Vector4 a(7.25f);
    #else
    Vector4 a(7.25f); /* Not constexpr under GCC < 4.7 */
    #endif

    CORRADE_COMPARE(a, Vector4(7.25f, 7.25f, 7.25f, 7.25f));
}

void VectorTest::constructOneComponent() {
    typedef Vector<1, Float> Vector1;

    /* Implicit constructor must work */
    constexpr Vector1 vec = 1.0f;
    CORRADE_COMPARE(vec, Vector1(1));
}

void VectorTest::constructConversion() {
    constexpr Vector4 a(1.3f, 2.7f, -15.0f, 7.0f);
    #ifndef CORRADE_GCC46_COMPATIBILITY
    constexpr Vector4i b(a);
    #else
    Vector4i b(a); /* Not constexpr under GCC < 4.7 */
    #endif

    CORRADE_COMPARE(b, Vector4i(1, 2, -15, 7));
}

void VectorTest::constructCopy() {
    constexpr Vector4 a(1.0f, 3.5f, 4.0f, -2.7f);
    constexpr Vector4 b(a);
    CORRADE_COMPARE(b, Vector4(1.0f, 3.5f, 4.0f, -2.7f));
}

void VectorTest::convert() {
    Vec3 a{1.5f, 2.0f, -3.5f};
    Vector3 b(1.5f, 2.0f, -3.5f);
    CORRADE_COMPARE(Vector3(a), b);
    CORRADE_COMPARE(Vec3(b).x, a.x);
    CORRADE_COMPARE(Vec3(b).y, a.y);
    CORRADE_COMPARE(Vec3(b).z, a.z);
}

void VectorTest::data() {
    Vector4 vector(4.0f, 5.0f, 6.0f, 7.0f);
    vector[2] = 1.0f;
    vector[3] = 1.5f;

    CORRADE_COMPARE(vector[2], 1.0f);
    CORRADE_COMPARE(vector[3], 1.5f);
    CORRADE_COMPARE(vector, Vector4(4.0f, 5.0f, 1.0f, 1.5f));

    /* Pointer chasings, i.e. *(b.data()[3]), are not possible */
    constexpr Vector4 a(1.0f, 2.0f, -3.0f, 4.5f);
    constexpr Float f = a[3];
    constexpr Float g = *a.data();
    CORRADE_COMPARE(f, 4.5f);
    CORRADE_COMPARE(g, 1.0f);
}

void VectorTest::compare() {
    CORRADE_VERIFY(Vector4(1.0f, -3.5f, 5.0f, -10.0f) == Vector4(1.0f + MathTypeTraits<Float>::epsilon()/2, -3.5f, 5.0f, -10.0f));
    CORRADE_VERIFY(Vector4(1.0f, -1.0f, 5.0f, -10.0f) != Vector4(1.0f, -1.0f + MathTypeTraits<Float>::epsilon()*2, 5.0f, -10.0f));

    CORRADE_VERIFY(Vector4i(1, -3, 5, -10) == Vector4i(1, -3, 5, -10));
    CORRADE_VERIFY(Vector4i(1, -3, 5, -10) != Vector4i(1, -2, 5, -10));
}

void VectorTest::compareComponentWise() {
    typedef BoolVector<3> BoolVector3;
    CORRADE_COMPARE(Vector3(1.0f, -1.0f, 5.0f) < Vector3(1.1f, -1.0f, 3.0f), BoolVector3(0x1));
    CORRADE_COMPARE(Vector3(1.0f, -1.0f, 5.0f) <= Vector3(1.1f, -1.0f, 3.0f), BoolVector3(0x3));
    CORRADE_COMPARE(Vector3(1.0f, -1.0f, 5.0f) >= Vector3(1.1f, -1.0f, 3.0f), BoolVector3(0x6));
    CORRADE_COMPARE(Vector3(1.0f, -1.0f, 5.0f) > Vector3(1.1f, -1.0f, 3.0f), BoolVector3(0x4));
}

void VectorTest::negative() {
    CORRADE_COMPARE(-Vector4(1.0f, -3.0f, 5.0f, -10.0f), Vector4(-1.0f, 3.0f, -5.0f, 10.0f));
}

void VectorTest::addSubtract() {
    Vector4 a(1.0f, -3.0f, 5.0f, -10.0f);
    Vector4 b(7.5f, 33.0f, -15.0f, 0.0f);
    Vector4 c(8.5f, 30.0f, -10.0f, -10.0f);

    CORRADE_COMPARE(a + b, c);
    CORRADE_COMPARE(c - b, a);
}

void VectorTest::multiplyDivide() {
    Vector4 vector(1.0f, 2.0f, 3.0f, 4.0f);
    Vector4 multiplied(-1.5f, -3.0f, -4.5f, -6.0f);

    CORRADE_COMPARE(vector*-1.5f, multiplied);
    CORRADE_COMPARE(-1.5f*vector, multiplied);
    CORRADE_COMPARE(multiplied/-1.5f, vector);

    Math::Vector<1, Byte> vectorChar(32);
    Math::Vector<1, Byte> multipliedChar(-48);
    CORRADE_COMPARE(vectorChar*-1.5f, multipliedChar);
    CORRADE_COMPARE(multipliedChar/-1.5f, vectorChar);
    CORRADE_COMPARE(-1.5f*vectorChar, multipliedChar);

    /* Divide vector with number and inverse */
    Vector4 divisor(1.0f, 2.0f, -4.0f, 8.0f);
    Vector4 result(1.0f, 0.5f, -0.25f, 0.125f);
    CORRADE_COMPARE(1.0f/divisor, result);
    CORRADE_COMPARE(-1550.0f/multipliedChar, vectorChar);
}

void VectorTest::multiplyDivideComponentWise() {
    Vector4 vec(1.0f, 2.0f, 3.0f, 4.0f);
    Vector4 multiplier(7.0f, -4.0f, -1.5f, 1.0f);
    Vector4 multiplied(7.0f, -8.0f, -4.5f, 4.0f);

    CORRADE_COMPARE(vec*multiplier, multiplied);
    CORRADE_COMPARE(multiplied/multiplier, vec);
}

void VectorTest::dot() {
    CORRADE_COMPARE(Vector4::dot({1.0f, 0.5f, 0.75f, 1.5f}, {2.0f, 4.0f, 1.0f, 7.0f}), 15.25f);
}

void VectorTest::dotSelf() {
    CORRADE_COMPARE(Vector4(1.0f, 2.0f, 3.0f, 4.0f).dot(), 30.0f);
}

void VectorTest::length() {
    CORRADE_COMPARE(Vector4(1.0f, 2.0f, 3.0f, 4.0f).length(), 5.4772256f);
}

void VectorTest::normalized() {
    CORRADE_COMPARE(Vector4(1.0f, 1.0f, 1.0f, 1.0f).normalized(), Vector4(0.5f, 0.5f, 0.5f, 0.5f));
}

void VectorTest::sum() {
    CORRADE_COMPARE(Vector3(1.0f, 2.0f, 4.0f).sum(), 7.0f);
}

void VectorTest::product() {
    CORRADE_COMPARE(Vector3(1.0f, 2.0f, 3.0f).product(), 6.0f);
}

void VectorTest::min() {
    /* Check also that initial value isn't initialized to 0 */
    CORRADE_COMPARE(Vector3(1.0f, -2.0f, 3.0f).min(), -2.0f);
}

void VectorTest::minAbs() {
    /* Check that initial value is absolute and also all others */
    CORRADE_COMPARE(Vector3(-2.0f, 1.0f, 3.0f).minAbs(), 1.0f);
    CORRADE_COMPARE(Vector3(1.0f, -2.0f, 3.0f).minAbs(), 1.0f);
}

void VectorTest::max() {
    /* Check also that initial value isn't initialized to 0 */
    CORRADE_COMPARE(Vector3(-1.0f, -2.0f, -3.0f).max(), -1.0f);
}

void VectorTest::maxAbs() {
    /* Check that initial value is absolute and also all others */
    CORRADE_COMPARE(Vector3(-5.0f, 1.0f, 3.0f).maxAbs(), 5.0f);
    CORRADE_COMPARE(Vector3(1.0f, -5.0f, 3.0f).maxAbs(), 5.0f);
}

void VectorTest::projected() {
    Vector3 line(1.0f, -1.0f, 0.5f);
    Vector3 projected = Vector3(1.0f, 2.0f, 3.0f).projected(line);

    CORRADE_COMPARE(projected, Vector3(0.222222f, -0.222222f, 0.111111f));
    CORRADE_COMPARE(projected.normalized(), line.normalized());
}

void VectorTest::projectedOntoNormalized() {
    std::ostringstream o;
    Error::setOutput(&o);

    Vector3 vector(1.0f, 2.0f, 3.0f);
    Vector3 line(1.0f, -1.0f, 0.5f);
    Vector3 projected = vector.projectedOntoNormalized(line);
    CORRADE_VERIFY(projected != projected);
    CORRADE_COMPARE(o.str(), "Math::Vector::projectedOntoNormalized(): line must be normalized\n");

    projected = vector.projectedOntoNormalized(line.normalized());
    CORRADE_COMPARE(projected, Vector3(0.222222f, -0.222222f, 0.111111f));
    CORRADE_COMPARE(projected.normalized(), line.normalized());
    CORRADE_COMPARE(projected, vector.projected(line));
}

void VectorTest::angle() {
    std::ostringstream o;
    Error::setOutput(&o);
    auto angle = Vector3::angle(Vector3(2.0f, 3.0f, 4.0f).normalized(), {1.0f, -2.0f, 3.0f});
    CORRADE_VERIFY(angle != angle);
    CORRADE_COMPARE(o.str(), "Math::Vector::angle(): vectors must be normalized\n");

    o.str({});
    angle = Vector3::angle({2.0f, 3.0f, 4.0f}, Vector3(1.0f, -2.0f, 3.0f).normalized());
    CORRADE_VERIFY(angle != angle);
    CORRADE_COMPARE(o.str(), "Math::Vector::angle(): vectors must be normalized\n");

    CORRADE_COMPARE(Vector3::angle(Vector3(2.0f,  3.0f, 4.0f).normalized(),
                                   Vector3(1.0f, -2.0f, 3.0f).normalized()),
                    Rad(1.162514f));
}

void VectorTest::debug() {
    std::ostringstream o;
    Debug(&o) << Vector4(0.5f, 15.0f, 1.0f, 1.0f);
    CORRADE_COMPARE(o.str(), "Vector(0.5, 15, 1, 1)\n");

    o.str({});
    Debug(&o) << "a" << Vector4() << "b" << Vector4();
    CORRADE_COMPARE(o.str(), "a Vector(0, 0, 0, 0) b Vector(0, 0, 0, 0)\n");
}

void VectorTest::configuration() {
    Corrade::Utility::Configuration c;

    Vector4 vec(3.0f, 3.125f, 9.0f, 9.55f);
    std::string value("3 3.125 9 9.55");

    c.setValue("vector", vec);
    CORRADE_COMPARE(c.value("vector"), value);
    CORRADE_COMPARE(c.value<Vector4>("vector"), vec);
}

}}}

CORRADE_TEST_MAIN(Magnum::Math::Test::VectorTest)