#include <stdio.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <signal.h>
#include <sys/wait.h>
#include <errno.h>
#include "epplet.h"

#if 0
#  define D(x) do {printf("%10s | %7d:  [debug] ", __FILE__, __LINE__); printf x; fflush(stdout);} while (0)
#else
#  define D(x) ((void) 0)
#endif
#define BEGMATCH(a, b)  (!strncasecmp((a), (b), (sizeof(b) - 1)))
#define NONULL(x)       ((x) ? (x) : (""))

Epplet_gadget close_button, in_bar, out_bar, in_label, out_label;
int in_val = 0, out_val = 0;
unsigned long max_in = 1, max_out = 1;

static void timer_cb(void *data);
static void close_cb(void *data);
static void in_cb(void *data, Window w);
static void out_cb(void *data, Window w);
static void parse_conf(void);

static void
timer_cb(void *data) {

  FILE *fp;
  char buff[1024];
  unsigned long a, b, c, d;
  unsigned long in_blks, out_blks;
  static unsigned long last_in = 0, last_out = 0, in_delta = 0, out_delta = 0;

  if ((fp = fopen("/proc/stat", "r")) == NULL) {
    D(("Failed to open /proc/stat -- %s\n", strerror(errno)));
    return;
  }
  do {
    fgets(buff, sizeof(buff), fp);
  } while (!BEGMATCH(buff, "disk_rblk"));

  sscanf(buff, "%*s %lu %lu %lu %lu", &a, &b, &c, &d);
  in_blks = a + b + c + d - last_in;
  if (last_in) {
    /* We must have some history data to do anything. */
    if (in_blks > max_in) {
      max_in = in_blks;
      Esnprintf(buff, sizeof(buff), "%lu", max_in);
      Epplet_modify_config("max_in", buff);
    }
    if (in_blks != in_delta) {
      in_val = (int) ((((float) in_blks) / max_in) * 100.0);
      Epplet_gadget_data_changed(in_bar);
      Esnprintf(buff, sizeof(buff), "I: %lu K/s", in_blks / 4);
      Epplet_change_label(in_label, buff);
    }
    in_delta = in_blks;
  }
  last_in += in_blks;

  fgets(buff, sizeof(buff), fp);
  sscanf(buff, "%*s %lu %lu %lu %lu", &a, &b, &c, &d);
  out_blks = a + b + c + d - last_out;
  if (last_out) {
    /* We must have some history data to do anything. */
    if (out_blks > max_out) {
      max_out = out_blks;
      Esnprintf(buff, sizeof(buff), "%lu", max_out);
      Epplet_modify_config("max_out", buff);
    }
    if (out_blks != out_delta) {
      out_val = (int) ((((float) out_blks) / max_out) * 100.0);
      Epplet_gadget_data_changed(out_bar);
      Esnprintf(buff, sizeof(buff), "O: %lu K/s", out_blks / 4);
      Epplet_change_label(out_label, buff);
    }
    out_delta = out_blks;
  }
  last_out += out_blks;

  fclose(fp);
  Esync();
  Epplet_timer(timer_cb, NULL, 0.5, "TIMER");
  return;
  data = NULL;
}

static void
close_cb(void *data) {

  Epplet_unremember();
  Esync();
  exit(0);
  data = NULL;
}

static void
in_cb(void *data, Window w) {

  Epplet_gadget_show(close_button);
  return;
  data = NULL;
  w = (Window) 0;
}

static void
out_cb(void *data, Window w) {

  Epplet_gadget_hide(close_button);
  return;
  data = NULL;
  w = (Window) 0;
}

static void
parse_conf(void) {

  char *s;

  s = Epplet_query_config("max_in");
  if (s) {
    max_in = strtoul(s, (char **) NULL, 10);
  }
  s = Epplet_query_config("max_out");
  if (s) {
    max_out = strtoul(s, (char **) NULL, 10);
  }
}

int
main(int argc, char **argv) {

  int prio;

  prio = getpriority(PRIO_PROCESS, getpid());
  setpriority(PRIO_PROCESS, getpid(), prio + 10);
  atexit(Epplet_cleanup);
  Epplet_Init("E-Disk", "0.1", "Enlightenment Disk I/O Monitor Epplet", 3, 3, argc, argv, 0);
  Epplet_load_config();
  parse_conf();

  close_button = Epplet_create_button(NULL, NULL, 34, 2, 0, 0, "CLOSE", 0, NULL, close_cb, NULL);
  in_label = Epplet_create_label(4, 4, "I: 0 K/s", 1);
  out_label = Epplet_create_label(4, 24, "O: 0 K/s", 1);
  in_bar = Epplet_create_hbar(4, 14, 40, 8, 0, &in_val);
  out_bar = Epplet_create_hbar(4, 36, 40, 8, 0, &out_val);
  Epplet_gadget_show(in_label);
  Epplet_gadget_show(in_bar);
  Epplet_gadget_show(out_label);
  Epplet_gadget_show(out_bar);
  Epplet_show();

  Epplet_register_focus_in_handler(in_cb, NULL);
  Epplet_register_focus_out_handler(out_cb, NULL);
  timer_cb(NULL);  /* Set everything up */
  Epplet_Loop();

  return 0;
}