# include <omp.h>
# include <cppad/cppad.hpp>
# include "../team_thread.hpp"

namespace {
     using CppAD::thread_alloc;

     // number of threads in this team
     size_t num_threads_;

     // used to inform CppAD when we are in parallel execution mode
     bool in_parallel(void)
     {     return omp_in_parallel() != 0; }

     // used to inform CppAD of the current thread number
     size_t thread_num(void)
     {     return static_cast<size_t>( omp_get_thread_num() ); }
}

bool team_create(size_t num_threads)
{
     bool ok = ! in_parallel();
     ok     &= thread_num() == 0;;
     ok     &= num_threads > 0;

     // Turn off dynamic thread adjustment
     omp_set_dynamic(0);

     // Set the number of OpenMP threads
     omp_set_num_threads( int(num_threads) );

     // setup for using CppAD::AD<double> in parallel
     thread_alloc::parallel_setup(num_threads, in_parallel, thread_num);
     thread_alloc::hold_memory(true);
     CppAD::parallel_ad<double>();

     // inform team_work of number of threads
     num_threads_ = num_threads;

     return ok;
}

bool team_work(void worker(void))
{     bool ok = ! in_parallel();
     ok     &= thread_num() == 0;;
     ok     &= num_threads_ > 0;

     int number_threads = int(num_threads_);
     int thread_num;
# pragma omp parallel for
     for(thread_num = 0; thread_num < number_threads; thread_num++)
          worker();
// end omp parallel for

     return ok;
}

bool team_destroy(void)
{     bool ok = ! in_parallel();
     ok     &= thread_num() == 0;;
     ok     &= num_threads_ > 0;

     // inform team_work of number of threads
     num_threads_ = 1;

     // Set the number of OpenMP threads to one
     omp_set_num_threads( int(num_threads_) );

     // inform CppAD no longer in multi-threading mode
     thread_alloc::parallel_setup(num_threads_, CPPAD_NULL, CPPAD_NULL);
     thread_alloc::hold_memory(false);
     CppAD::parallel_ad<double>();

     return ok;
}

const char* team_name(void)
{     return "openmp"; }