#include <stddef.h>
#include <stdint.h>
#include <ulib.h>
#include "ls.h"
#include "macros.h"

struct {
  char *specificproc;
  int32_t pid;
} PCTL_LS_CONFIG = {
  .specificproc = NULL,
  .pid = -1,
};

static Arg ARGS[] = {
  ARG("-proc", ARG_STRING, &PCTL_LS_CONFIG.specificproc),
  ARG("-pid", ARG_INT, &PCTL_LS_CONFIG.pid),
  ARG_END(),
};

const char *human_size(uint64_t bytes, char *buf, size_t bufsize) {
  static const char *units[] = { "B", "KiB", "MiB", "GiB", "TiB", "PiB" };
  int unit = 0;

  // Scale down until value fits nicely
  uint64_t rem = 0;
  while (bytes >= 1024 && unit < (int)(sizeof(units)/sizeof(units[0])) - 1) {
    rem = bytes % 1024;
    bytes /= 1024;
    unit++;
  }

  if (unit == 0) {
    // Just bytes
    usnprintf(buf, bufsize, "%llu %s", (unsigned long long)bytes, units[unit]);
  } else {
    // Show one decimal place without using floats
    // Multiply remainder by 10 to get first decimal digit
    uint64_t frac = (rem * 10 + 512) / 1024; // rounded
    if (frac == 10) { // handle carry, e.g. 1023.9 -> 1024.0
      bytes++;
      frac = 0;
    }

    if (frac > 0) usnprintf(buf, bufsize, "%llu.%llu %s", (unsigned long long)bytes, (unsigned long long)frac, units[unit]);
    else usnprintf(buf, bufsize, "%llu %s", (unsigned long long)bytes, units[unit]);
  }

  return buf;
}
  
  
void pctl_ls(void) {
  int32_t ret;
  if ((ret = parse_args(SUBCMD_ARGS(), SUBCMD_ARGSLEN(), ARGS)) < 0) {
    uprintf("pctl ls: Could not parse args: %d\n", ret);
    return;
  }

  static const char *states[] = {"embryo", "ready", "zombie", "waiting", "died"};

  uint64_t procslen = processctl(-1, PCTL_PLS_SZ, 0, 0, 0);

  char *namebuf = dlmalloc(34);
  char *membuf = dlmalloc(20);
  
  uprintf("%-30s %s %-6s %-15s %-8s\n", "NAME", "PID", "TYPE", "MEMORY", "STATE");
  for (size_t i = 0; i < procslen; i++) {
    ProcStat stat = ZERO(&stat);

    string_memset(namebuf, 0, 34);
    string_memset(membuf, 0, 20);

    int32_t r = processctl(-1, PCTL_PLS_STAT, i, (uint64_t)&stat, 0);
    if (r == E_OK) {
      if (PCTL_LS_CONFIG.specificproc != NULL
       && string_strcmp(stat.name, PCTL_LS_CONFIG.specificproc) != 0) {
        continue;
      }

      if (PCTL_LS_CONFIG.pid != -1 && stat.pid != PCTL_LS_CONFIG.pid) {
        continue;
      }

      string_memcpy(namebuf, stat.name, 30);
      namebuf[31] = namebuf[32] = namebuf[33] = '.';

      // Too big format string causes a stack overflow. This is an issue with printf ;(
      uprintf("%-30s %-3lu %-6s %-15s ",
              namebuf,
              stat.pid,
              stat.kern ? "KERNEL" : "USER",
              human_size(stat.usemem, membuf, 20)
            );
      uprintf("%-8s", states[stat.state]);
      uprintf("\n");
    }
  }
}