#include <sics.h>
#include <sys/time.h>
#include "statistics.h"

typedef struct timeval tv_t;

struct Statistics {
  tv_t tim;
  tv_t last;
  tv_t total;
  long cnt;
  char *name;
  Statistics *next;
};

static Statistics *current = NULL;
static tv_t last, lastStat;
static Statistics *idle = NULL, *list = NULL;
static int init = 1;
/*-----------------------------------------------------------------------*/
tv_t timeDif(tv_t t1, tv_t t2)
{
  tv_t result;

  result.tv_usec = t2.tv_usec - t1.tv_usec;
  result.tv_sec = t2.tv_sec - t1.tv_sec;
  if (result.tv_usec < 0) {
    result.tv_usec += 1000000;
    result.tv_sec--;
  }
  if (result.tv_sec < 0) {
    result.tv_sec += 24 * 3600;
  }
  return result;
}

/*-----------------------------------------------------------------------*/
void timeAdd(tv_t * t1, tv_t t2)
{
  t1->tv_usec += t2.tv_usec;
  t1->tv_sec += t2.tv_sec + (t1->tv_usec / 1000000);
  t1->tv_usec %= 1000000;
}

/*-----------------------------------------------------------------------*/
double timeFloat(tv_t t)
{
  return t.tv_sec + 1e-6 * t.tv_usec;
}

/*-----------------------------------------------------------------------*/
int StatisticsCommand(SConnection * con, SicsInterp * pSics, void *pData,
                      int argc, char *argv[])
{
  Statistics *p;
  tv_t now;
  double dif, percent, full, dt, calls;

  gettimeofday(&now, 0);
  dif = timeFloat(timeDif(lastStat, now));
  SCPrintf(con, eLog, "calls/s time[%%] full[%%] mean[ms]  command");
  SCPrintf(con, eLog, "----------------------------------------------");
  for (p = list; p != NULL; p = p->next) {
    if (dif > 0) {
      calls = p->cnt / dif;
      percent = timeFloat(p->tim) * 100 / dif;
      full = timeFloat(p->total) * 100 / dif;
      if (full > 0 || percent > 0) {
        if (p->cnt > 0) {
          dt = timeFloat(p->total) * 1000.0 / p->cnt;
        } else {
          dt = 0;
        }
        SCPrintf(con, eLog, "%7.1f %7.1f %7.1f %8.2f  %s", calls,
                 percent, full, dt, p->name);
      }
    }
    p->cnt = 0;
    p->tim.tv_sec = 0;
    p->tim.tv_usec = 0;
    p->total.tv_sec = 0;
    p->total.tv_usec = 0;
  }
  SCPrintf(con, eLog, "----------------------------------------------");
  SCPrintf(con, eLog, "total time %.2f", dif);
  lastStat = now;
  return 1;
}

/*-----------------------------------------------------------------------*/
Statistics *StatisticsNew(char *name)
{
  Statistics *new;

  if (init) {
    gettimeofday(&lastStat, 0);
    last = lastStat;
    init = 0;
  }
  new = calloc(1, sizeof(*new));
  if (new) {
    new->cnt = 0;
    new->tim.tv_sec = 0;
    new->tim.tv_usec = 0;
    new->total.tv_sec = 0;
    new->total.tv_usec = 0;
    new->last.tv_sec = -1;
    new->next = list;
    new->name = strdup(name);
    list = new;
  }
  return new;
}

/*-----------------------------------------------------------------------*/
void StatisticsKill(Statistics * stat)
{
  Statistics *p, **last;

  /* find in list */
  last = &list;
  for (p = list; p != NULL && p != stat; p = p->next) {
    last = &p->next;
  }

  /* remove from list */
  if (p == stat) {
    *last = p->next;
  }

  /* kill it */
  if (stat->name) {
    free(stat->name);
    stat->name = NULL;
  }
  free(stat);
}

/*-----------------------------------------------------------------------*/
Statistics *StatisticsBegin(Statistics * stat)
{
  Statistics *res;
  tv_t now;

  res = current;
  gettimeofday(&now, 0);
  if (current != NULL) {
    timeAdd(&current->tim, timeDif(last, now));
  }
  last = now;
  current = stat;
  stat->last = now;
  stat->cnt++;
  return res;
}

/*-----------------------------------------------------------------------*/
void StatisticsEnd(Statistics * stat)
{
  tv_t now;

  gettimeofday(&now, 0);
  timeAdd(&current->tim, timeDif(last, now));
  last = now;
  if (current != NULL) {
    if (current->last.tv_sec >= 0) {
      timeAdd(&current->total, timeDif(current->last, now));
    }
    current->last.tv_sec = -1;
  }
  current = stat;
}

/*-----------------------------------------------------------------------*/
void StatisticsInit(void)
{
  if (idle == NULL) {
    AddCmd("statistics", StatisticsCommand);
    last = lastStat;
    idle = StatisticsNew("<idle>");
    current = idle;
  }
}