#include <cctk.h>

#include <cstdio>
#include <cstdlib>
#include <string>

// IRIX wants this before <time.h>
#if HAVE_SYS_TYPES_H
#  include <sys/types.h>
#endif

#if TIME_WITH_SYS_TIME
#  include <sys/time.h>
#  include <time.h>
#else
#  if HAVE_SYS_TIME_H
#    include <sys/time.h>
#  elif HAVE_TIME_H
#    include <time.h>
#  endif
#endif

#if HAVE_UNISTD_H
#  include <unistd.h>
#endif

#include "startup_time.hh"



namespace CarpetLib {
  
  using namespace std;
  
  
  
  // Return the current wall time
  static
  double
  get_walltime ()
  {
#ifdef HAVE_TIME_GETTIMEOFDAY
    // get the current time
    struct timeval tv;
    gettimeofday (& tv, 0);
    return tv.tv_sec + tv.tv_usec / 1.0e6;
#else
    return 0.0;
#endif
  }
  
  
  
  void
  output_startup_time ()
  {
    char * const cactus_starttime = getenv ("CACTUS_STARTTIME");
    if (not cactus_starttime) {
      CCTK_VWarn (CCTK_WARN_PICKY,
                  __LINE__, __FILE__, CCTK_THORNSTRING,
                  "Could not determine Cactus startup time (environment variable CACTUS_STARTTIME is not set; it should be set to the output of \"date +%%s\")");
      return;
    }
    
    double starttime;
    int const iret = sscanf (cactus_starttime, "%lf", &starttime);
    if (iret != 1) {
      CCTK_VWarn (CCTK_WARN_COMPLAIN,
                  __LINE__, __FILE__, CCTK_THORNSTRING,
                  "Could not determine Cactus startup time (environment variable CACTUS_STARTTIME has illegal value \"%s\"; it should instead be set to the output of \"date +%%s\", which is a single number)",
                  cactus_starttime);
      return;
    }
    
    double const currenttime = get_walltime ();
    double const startuptime = currenttime - starttime;
    
    CCTK_VInfo (CCTK_THORNSTRING,
                "Process startup time was %.3g seconds", startuptime);
  }
  
} // namespace CarpetLib