/* EINA - EFL data type library
 * Copyright (C) 2008 Cedric Bail
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library;
 * if not, see <http://www.gnu.org/licenses/>.
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <stdlib.h>
#include <string.h>
#include <time.h>

#include "eina_counter.h"
#include "eina_inlist.h"
#include "eina_error.h"
#include "eina_private.h"

/*============================================================================*
 *                                  Local                                     *
 *============================================================================*/

typedef struct _Eina_Clock Eina_Clock;

struct _Eina_Counter
{
   Eina_Inlist __list;

   Eina_Inlist *clocks;
   const char *name;
};

struct _Eina_Clock
{
   Eina_Inlist __list;

   struct timespec start;
   struct timespec end;
   int specimen;

   Eina_Bool valid;
};

static int _eina_counter_init_count = 0;
static int EINA_COUNTER_ERROR_OUT_OF_MEMORY = 0;

/*============================================================================*
 *                                 Global                                     *
 *============================================================================*/

/*============================================================================*
 *                                   API                                      *
 *============================================================================*/

EAPI int
eina_counter_init(void)
{
   _eina_counter_init_count++;

   if (_eina_counter_init_count == 1)
     {
	eina_error_init();
	EINA_COUNTER_ERROR_OUT_OF_MEMORY  = eina_error_register("Eina_Counter out of memory");
     }

   return _eina_counter_init_count;
}

EAPI int
eina_counter_shutdown(void)
{
   _eina_counter_init_count--;

   if (_eina_counter_init_count == 0) eina_error_shutdown();

   return _eina_counter_init_count;
}

EAPI Eina_Counter *
eina_counter_add(const char *name)
{
   Eina_Counter *counter;
   int length;

   if (!name) return NULL;

   length = strlen(name) + 1;

   counter = calloc(1, sizeof (Eina_Counter) + length);
   if (!counter)
     {
	eina_error_set(EINA_COUNTER_ERROR_OUT_OF_MEMORY);
	return NULL;
     }

   counter->name = (char*) (counter + 1);
   memcpy((char*) counter->name, name, length);

   return counter;
}

EAPI void
eina_counter_delete(Eina_Counter *counter)
{
   if (!counter) return ;

   while (counter->clocks)
     {
	Eina_Clock *clock = (Eina_Clock *) counter->clocks;

	counter->clocks = eina_inlist_remove(counter->clocks, counter->clocks);
	free(clock);
     }

   free(counter);
}

EAPI void
eina_counter_start(Eina_Counter *counter)
{
   Eina_Clock *clk;
   struct timespec tp;

   if (!counter) return ;
   if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &tp) != 0) return ;

   clk = calloc(1, sizeof (Eina_Clock));
   if (!clk)
     {
	eina_error_set(EINA_COUNTER_ERROR_OUT_OF_MEMORY);
	return ;
     }

   counter->clocks = eina_inlist_prepend(counter->clocks, clk);

   clk->valid = EINA_FALSE;
   clk->start = tp;
}

EAPI void
eina_counter_stop(Eina_Counter *counter, int specimen)
{
   Eina_Clock *clk;
   struct timespec tp;

   if (!counter) return ;
   if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &tp) != 0) return ;

   clk = (Eina_Clock *) counter->clocks;

   if (clk->valid == EINA_TRUE) return ;

   clk->end = tp;
   clk->specimen = specimen;
   clk->valid = EINA_TRUE;
}

EAPI void
eina_counter_dump(Eina_Counter *counter, FILE *out)
{
   Eina_Clock *clk;

   fprintf(out, "# specimen\texperiment time\tstarting time\tending time\n");

   EINA_INLIST_ITER_LAST(counter->clocks, clk)
     {
	if (clk->valid == EINA_TRUE)
	  fprintf(out, "%i\t%li\t%li\t%li\n",
		  clk->specimen,
		  (clk->end.tv_sec * 1000000000 + clk->end.tv_nsec) - (clk->start.tv_sec * 1000000000 + clk->start.tv_nsec),
		  clk->start.tv_sec * 1000000000 + clk->start.tv_nsec,
		  clk->end.tv_sec * 1000000000 + clk->end.tv_nsec);
     }
}