//  Copyright Daniel James 2005. Use, modification, and distribution are
//  subject to the Boost Software License, Version 1.0. (See accompanying
//  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#include <boost/functional/hash.hpp>

#include <boost/test/test_tools.hpp>
#include <boost/test/test_case_template.hpp>
using boost::unit_test::test_suite;

#include <cmath>
#include <boost/limits.hpp>
#include <boost/mpl/list.hpp>

BOOST_TEST_CASE_TEMPLATE_FUNCTION(float_tests, T)
{
    boost::hash<T> x1;

    T zero = 0;
    T minus_zero = (T) -1 * zero;

    BOOST_CHECK_EQUAL(zero, minus_zero);
    BOOST_CHECK_EQUAL(x1(zero), x1(minus_zero));

    using namespace std;

    if(std::numeric_limits<T>::has_infinity) {
        T infinity = (T) 1. / zero;
        T infinity2 = -log(zero);
        T infinity3 = (T) -1. / minus_zero;
        T infinity4 = std::numeric_limits<T>::infinity();
        
        T minus_infinity = (T) -1. / zero;
        T minus_infinity2 = log(zero);
        T minus_infinity3 = (T) 1. / minus_zero;

        BOOST_CHECK_EQUAL(infinity, infinity2);
        BOOST_CHECK_EQUAL(infinity, infinity3);
        BOOST_CHECK_EQUAL(infinity, infinity4);
        BOOST_CHECK_EQUAL(x1(infinity), x1(infinity2));
        BOOST_CHECK_EQUAL(x1(infinity), x1(infinity3));
        BOOST_CHECK_EQUAL(x1(infinity), x1(infinity4));

        BOOST_CHECK_EQUAL(minus_infinity, minus_infinity2);
        BOOST_CHECK_EQUAL(x1(minus_infinity), x1(infinity2));
        BOOST_CHECK_EQUAL(minus_infinity, minus_infinity3);
        BOOST_CHECK_EQUAL(x1(minus_infinity), x1(minus_infinity3));

        BOOST_CHECK(infinity != minus_infinity);

        // My hash fails this one, I guess it's not that bad.
        BOOST_WARN(x1(infinity) != x1(minus_infinity));

        if(std::numeric_limits<T>::has_denorm == denorm_present) {
            BOOST_CHECK(x1(std::numeric_limits<T>::denorm_min()) != x1(infinity));
            BOOST_CHECK(x1(std::numeric_limits<T>::denorm_min()) != x1(minus_infinity));
        }

        if(std::numeric_limits<T>::has_quiet_NaN) {
            // Another two failures, should I work around this?
            BOOST_WARN(x1(std::numeric_limits<T>::quiet_NaN()) != x1(infinity));
            BOOST_WARN(x1(std::numeric_limits<T>::quiet_NaN()) != x1(minus_infinity));
        }
    }

    T max = (std::numeric_limits<T>::max)();
    T half_max = max / 2;
    T quater_max = max / 4;
    T three_quater_max = max - quater_max;
    BOOST_CHECK_EQUAL(x1(max), x1(max));
    BOOST_CHECK(x1(max) != x1(quater_max));
    BOOST_CHECK(x1(max) != x1(half_max));
    BOOST_CHECK(x1(max) != x1(three_quater_max));
    BOOST_CHECK_EQUAL(x1(quater_max), x1(quater_max));
    BOOST_CHECK(x1(quater_max) != x1(half_max));
    BOOST_CHECK(x1(quater_max) != x1(three_quater_max));
    BOOST_CHECK_EQUAL(x1(half_max), x1(half_max));
    BOOST_CHECK(x1(half_max) != x1(three_quater_max));
    BOOST_CHECK(x1(three_quater_max) == x1(three_quater_max));

    T v1 = asin((T) 1);
    T v2 = acos((T) 0);
    BOOST_CHECK_EQUAL(v1, v2);
    BOOST_CHECK_EQUAL(x1(v1), x1(v2));

    BOOST_CHECK(x1(std::numeric_limits<T>::epsilon()) != x1((T) 0));

    if(std::numeric_limits<T>::has_denorm == denorm_present) {
        BOOST_CHECK(x1(std::numeric_limits<T>::denorm_min()) != x1(zero));
    }

    if(std::numeric_limits<T>::has_quiet_NaN) {
        BOOST_CHECK(x1(std::numeric_limits<T>::quiet_NaN()) != x1(zero));
    }
}

test_suite* init_unit_test_suite(int, char*[])
{
    test_suite* test= BOOST_TEST_SUITE( "Test case template example" );
    typedef boost::mpl::list<float, double, long double> float_types;
    test->add(BOOST_TEST_CASE_TEMPLATE(float_tests, float_types));
    return test;
}