/* boost validate.cpp
 *
 * Copyright Jens Maurer 2000
 * Distributed under 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)
 *
 * $Id$
 */

#if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
#pragma warning( disable : 4786 )
#endif

#include <iostream>
#include <sstream>
#include <string>
#include <cmath>
#include <iterator>
#include <vector>
#include <boost/random.hpp>
#include <boost/config.hpp>
#include <boost/preprocessor/stringize.hpp>

#include <boost/test/test_tools.hpp>
#include <boost/test/included/test_exec_monitor.hpp>

#ifdef BOOST_NO_STDC_NAMESPACE
  namespace std { using ::abs; using ::fabs; using ::pow; }
#endif


/*
 * General portability note:
 * MSVC mis-compiles explicit function template instantiations.
 * For example, f<A>() and f<B>() are both compiled to call f<A>().
 * BCC is unable to implicitly convert a "const char *" to a std::string
 * when using explicit function template instantiations.
 *
 * Therefore, avoid explicit function template instantiations.
 */

/*
 * Check function signatures
 */

#if BOOST_WORKAROUND( __BORLANDC__, BOOST_TESTED_AT( 0x570) )
#pragma warn -par
#endif
template<class URNG, class Dist>
void instantiate_dist(URNG& urng, const char * name, const Dist& dist)
{
  // this makes a copy of urng
  boost::variate_generator<URNG, Dist> gen(urng, dist);

  // this keeps a reference to urng
  boost::variate_generator<URNG&, Dist> genref(urng, dist);

  BOOST_CHECK(gen.engine() == genref.engine());

#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
  // and here is a pointer to (a copy of) the urng
  URNG copy = urng;
  boost::variate_generator<URNG*, Dist> genptr(&copy, dist);
#endif

  for(int i = 0; i < 1000; ++i) {
    (void) gen();
    (void) genref();
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
    (void) genptr();
#endif
  }
  // If the values are not exactly equal, we cannot
  // rely on them being close...
  typename Dist::result_type g = gen();
  BOOST_CHECK_EQUAL(g, genref());
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
  BOOST_CHECK_EQUAL(g, genptr());
#endif

  (void) gen.engine();
  gen.distribution().reset();

  Dist d = dist;            // copy ctor
  d = dist;                 // copy assignment

#ifndef BOOST_RANDOM_NO_STREAM_OPERATORS
  {
    std::ostringstream file;
    file << urng << std::endl;
    file << d;
    std::istringstream input(file.str());
    // std::cout << file.str() << std::endl;
    URNG restored_engine;
    input >> restored_engine;
    input >> std::ws;
    Dist restored_dist;
    input >> restored_dist;
#if !defined(BOOST_MSVC) || BOOST_MSVC > 1300 // MSVC brokenness
    boost::variate_generator<URNG, Dist> old(urng, d);
    boost::variate_generator<URNG, Dist> restored(restored_engine, restored_dist);
    // advance some more so that state is exercised
    for(int i = 0; i < 1000; ++i) {
      (void) old();
      (void) restored();
    }
    BOOST_CHECK_MESSAGE((std::abs(old()-restored()) < 0.0001),
                        (std::string(name) + " old == restored_dist"));
#endif // BOOST_MSVC
  }
#endif // BOOST_RANDOM_NO_STREAM_OPERATORS
}

template<class URNG, class RealType>
void instantiate_real_dist(URNG& urng, RealType /* ignored */)
{
  instantiate_dist(urng, "uniform_01",
                   boost::uniform_01<RealType>());
  instantiate_dist(urng, "uniform_real",
                   boost::uniform_real<RealType>(0, 2.1));
  instantiate_dist(urng, "triangle_distribution",
                   boost::triangle_distribution<RealType>(1, 1.5, 7));
  instantiate_dist(urng, "exponential_distribution",
                   boost::exponential_distribution<RealType>(5));
  instantiate_dist(urng, "normal_distribution",
                   boost::normal_distribution<RealType>());
  instantiate_dist(urng, "lognormal_distribution",
                   boost::lognormal_distribution<RealType>(1, 1));
  instantiate_dist(urng, "cauchy_distribution",
                   boost::cauchy_distribution<RealType>(1));
  instantiate_dist(urng, "gamma_distribution",
                   boost::gamma_distribution<RealType>(1));
}

template<class URNG, class T>
void test_seed(URNG & urng, const T & t) {
    URNG urng2(t);
    BOOST_CHECK(urng == urng2);
    urng2.seed(t);
    BOOST_CHECK(urng == urng2);
}

// rand48 uses non-standard seeding
template<class T>
void test_seed(boost::rand48 & urng, const T & t) {
    boost::rand48 urng2(t);
    urng2.seed(t);
}

template<class URNG, class ResultType>
void instantiate_seed(const URNG &, const ResultType &) {
    {
        URNG urng;
        URNG urng2;
        urng2.seed();
        BOOST_CHECK(urng == urng2);
    }
    {
        int value = 127;
        URNG urng(value);

        // integral types
        test_seed(urng, static_cast<char>(value));
        test_seed(urng, static_cast<signed char>(value));
        test_seed(urng, static_cast<unsigned char>(value));
        test_seed(urng, static_cast<short>(value));
        test_seed(urng, static_cast<unsigned short>(value));
        test_seed(urng, static_cast<int>(value));
        test_seed(urng, static_cast<unsigned int>(value));
        test_seed(urng, static_cast<long>(value));
        test_seed(urng, static_cast<unsigned long>(value));
#if !defined(BOOST_NO_INT64_T)
        test_seed(urng, static_cast<boost::int64_t>(value));
        test_seed(urng, static_cast<boost::uint64_t>(value));
#endif

        // floating point types
        test_seed(urng, static_cast<float>(value));
        test_seed(urng, static_cast<double>(value));
        test_seed(urng, static_cast<long double>(value));
    }
}

template<class URNG, class ResultType>
void instantiate_urng(const std::string & s, const URNG & u, const ResultType & r)
{
  std::cout << "Basic tests for " << s;
  URNG urng;
  instantiate_seed(u, r);                       // seed() member function
  int a[URNG::has_fixed_range ? 5 : 10];        // compile-time constant
  (void) a;   // avoid "unused" warning
  typename URNG::result_type x1 = urng();
  ResultType x2 = x1;
  (void) &x2;           // avoid "unused" warning

  URNG urng2 = urng;             // copy constructor
#if !defined(BOOST_MSVC) || BOOST_MSVC > 1300 // MSVC brokenness
  BOOST_CHECK(urng == urng2);     // operator==
  BOOST_CHECK(!(urng != urng2));  // operator!=
  urng();
  urng2 = urng;                  // copy assignment
  BOOST_CHECK(urng == urng2);
  urng2 = URNG(urng2);           // copy constructor, not templated constructor
  BOOST_CHECK(urng == urng2);
#endif // BOOST_MSVC

  const std::vector<int> v(9999u, 0x41);
  std::vector<int>::const_iterator it = v.begin();
  std::vector<int>::const_iterator it_end = v.end();
  URNG urng3(it, it_end);
  BOOST_CHECK(it != v.begin());
  std::iterator_traits<std::vector<int>::const_iterator>::difference_type n_words = (it - v.begin());
  std::cout << "; seeding uses " << n_words << " words" << std::endl;

  it = v.end();
  BOOST_CHECK_THROW(urng3.seed(it, it_end), std::invalid_argument);

  if(n_words > 1) {
    it = v.end();
    --it;
    BOOST_CHECK_THROW(urng3.seed(it, it_end), std::invalid_argument);
  }

  // check for min/max members
  ResultType min = (urng3.min)();
  (void) &min;
  ResultType max = (urng3.max)();
  (void) &max;

#ifndef BOOST_RANDOM_NO_STREAM_OPERATORS
  // Streamable concept not supported for broken compilers

  // advance a little so that state is relatively arbitrary
  for(int i = 0; i < 9307; ++i)
    urng();
  urng2 = urng;

  {
    // narrow stream first
    std::ostringstream file;
    file << urng;
    // move forward
    urng();
    // restore old state
    std::istringstream input(file.str());
    input >> urng;
    // std::cout << file.str() << std::endl;
#if !defined(BOOST_MSVC) || BOOST_MSVC > 1300 // MSVC brokenness
    // advance some more so that state is exercised
    for(int i = 0; i < 10000; ++i) {
      urng();
      urng2();
    }
    BOOST_CHECK(urng == urng2);
#endif // BOOST_MSVC
  }
  
  urng2 = urng;
#if !defined(BOOST_NO_STD_WSTREAMBUF) && !defined(BOOST_NO_STD_WSTRING)
  {
    // then wide stream
    std::wostringstream file;
    file << urng;
    // move forward
    urng();
    std::wistringstream input(file.str());
    input >> urng;
#if !defined(BOOST_MSVC) || BOOST_MSVC > 1300 // MSVC brokenness
    // advance some more so that state is exercised
    for(int i = 0; i < 10000; ++i) {
      urng();
      urng2();
    }
    BOOST_CHECK(urng == urng2);
#endif // BOOST_MSVC
  }
#endif // BOOST_NO_STD_WSTREAMBUF, BOOST_NO_STD_WSTRING
#endif // BOOST_RANDOM_NO_STREAM_OPERATORS

  // instantiate various distributions with this URNG
  instantiate_dist(urng, "uniform_smallint", boost::uniform_smallint<>(0, 11));
  instantiate_dist(urng, "uniform_int", boost::uniform_int<>(-200, 20000));
  instantiate_dist(urng, "bernoulli_distribution",
                   boost::bernoulli_distribution<>(0.2));
  instantiate_dist(urng, "binomial_distribution",
                   boost::binomial_distribution<>(4, 0.2));
  instantiate_dist(urng, "geometric_distribution",
                   boost::geometric_distribution<>(0.8));
  instantiate_dist(urng, "poisson_distribution",
                   boost::poisson_distribution<>(1));

  instantiate_real_dist(urng, 1.0f);
  instantiate_real_dist(urng, 1.0);
  instantiate_real_dist(urng, 1.0l);

#if 0
  // We cannot compare the outcomes before/after save with std::abs(x-y)
  instantiate_dist("uniform_on_sphere",
                   boost::uniform_on_sphere<URNG>(urng, 2));
#endif
}

template<class T>
void extra_tests(T*)
{
}

#if !defined(BOOST_NO_INT64_T) && !defined(BOOST_NO_INTEGRAL_INT64_T)
void extra_tests(boost::rand48*)
{
  using namespace boost;
  rand48 rnd(boost::int32_t(5));
  rand48 rnd2(boost::uint64_t(0x80000000) * 42);
  rnd.seed(boost::int32_t(17));
  rnd2.seed(boost::uint64_t(0x80000000) * 49);
}
#endif

void extra_tests(boost::minstd_rand*)
{
  using namespace boost;
  minstd_rand mstd(42);
  mstd.seed(17);
}

void extra_tests(boost::mt19937*)
{
  using namespace boost;
  minstd_rand mstd(42);
  mstd.seed(17);

  mt19937 mt(boost::uint32_t(17));  // needs to be an exact type match for MSVC
  int i = 42;
  mt.seed(boost::uint32_t(i));
  mt19937 mt2(mstd);
  mt2.seed(mstd);

  random_number_generator<mt19937> std_rng(mt2);
  (void) std_rng(10);
}

void instantiate_all()
{
  using namespace boost;
  
  typedef boost::random::lagged_fibonacci<boost::uint32_t, 24, 607, 273> lagged_fibonacci;

  typedef BOOST_RANDOM_URNG_TEST::result_type result_type;
  instantiate_urng(BOOST_PP_STRINGIZE(BOOST_RANDOM_URNG_TEST), BOOST_RANDOM_URNG_TEST(), static_cast<result_type>(0));
  BOOST_RANDOM_URNG_TEST* type_ptr = 0;
  extra_tests(type_ptr);

}


#if defined(BOOST_MSVC) && _MSC_VER < 1300

// These explicit instantiations are necessary, otherwise MSVC does
// not find the <boost/operators.hpp> inline friends.
// We ease the typing with a suitable preprocessor macro.
#define INSTANT(x) \
template class boost::uniform_smallint<x>; \
template class boost::uniform_int<x>; \
template class boost::uniform_real<x>; \
template class boost::bernoulli_distribution<x>; \
template class boost::geometric_distribution<x>; \
template class boost::triangle_distribution<x>; \
template class boost::exponential_distribution<x>; \
template class boost::normal_distribution<x>; \
template class boost::uniform_on_sphere<x>; \
template class boost::lognormal_distribution<x>;

INSTANT(boost::minstd_rand0)
INSTANT(boost::minstd_rand)
INSTANT(boost::ecuyer1988)
INSTANT(boost::kreutzer1986)
INSTANT(boost::hellekalek1995)
INSTANT(boost::mt19937)
INSTANT(boost::mt11213b)

#undef INSTANT
#endif


int test_main(int, char*[])
{
  instantiate_all();
  return 0;
}