#include "readUtil.h"
#include "myMonitoringTool.h"
#include <assert.h>

// Rip an integer out of a string.
int extract_int(char *str) {
  ///_|> descry: takes an integer out of a string
  ///_|> str: string to search
  ///_|> returning: void
  char num[LINE_BUF];
  int num_idx = 0;

  int str_idx = 0;
  while (str[str_idx] != '\0') {
    if (isdigit(str[str_idx])) {
      num[num_idx] = str[str_idx];
      num_idx++;
    }
    str_idx++;
  }
  num[num_idx] = '\0';

  return atoi(num);
}

int get_file_line_value(char *filename, int linenum) {
  ///_|> descry: Get the integer at a specific line in a value. First line in
  /// file is line num
  ///_|> filename: file to search
  ///_|> linenum: line to read
  ///_|> returning: integer thats found
  FILE *file = fopen(filename, "r");
  if (file == NULL) {
    printf("could not open %s", filename);
    exit(1);
  }
  char line[LINE_BUF];
  for (int i = 0; i <= linenum; i++) {
    fgets(line, LINE_BUF, file);
  }
  fclose(file);
  char label[LINE_BUF];
  char sep[LINE_BUF];
  int value;
  char tail[LINE_BUF];
  sscanf(line, "%s %s %d %s", label, sep, &value, tail);
  return extract_int(line);
}

long read_cpu_util() {
  ///_|> decry: Read total cpu time usage from /proc/stat
  ///_|> returning: cpu usage since boot
  char dummy[LINE_BUF];
  long user;
  long nice;
  long system;
  long idle; // not counted
  long io;
  long intr;
  long sintr;
  long steal;
  long guest;
  long guest_nice;
  FILE *file = fopen("/proc/stat", "r");
  if (file == NULL) {
    printf("could not open /proc/stat");
    exit(1);
  }
  fscanf(file, "%s %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld", dummy, &user,
         &nice, &system, &idle, &io, &intr, &sintr, &steal, &guest,
         &guest_nice);
  fclose(file);
  // return value is in 1/100 s
  return user + nice + system + io + intr + sintr;
}