helpers.sh

get_tmux_option() {
  local option="$1"
  local default_value="$2"
  local option_value="$(tmux show-option -gqv "$option")"
  if [ -z "$option_value" ]; then
    echo "$default_value"
  else
    echo "$option_value"
  fi
}

is_osx() {
  [ $(uname) == "Darwin" ]
}

is_freebsd() {
  [ $(uname) == "FreeBSD" ]
}

is_openbsd() {
  [ $(uname) == "OpenBSD" ]
}

is_linux() {
  [ $(uname) == "Linux" ]
}

is_cygwin() {
  command -v WMIC &> /dev/null
}

is_linux_iostat() {
  # Bug in early versions of linux iostat -V return error code
  iostat -c &> /dev/null
}

# is second float bigger or equal?
fcomp() {
  awk -v n1=$1 -v n2=$2 'BEGIN {if (n1<=n2) exit 0; exit 1}'
}

load_status() {
  local percentage=$1
  if fcomp 80 $percentage; then
    echo "high"
  elif fcomp 30 $percentage && fcomp $percentage 80; then
    echo "medium"
  else
    echo "low"
  fi
}

cpus_number() {
  if is_linux; then
    nproc
  else
    sysctl -n hw.ncpu
  fi
}

command_exists() {
  local command="$1"
  command -v "$command" &> /dev/null
}

get_tmp_dir() {
  local tmpdir="${TMPDIR:-${TMP:-${TEMP:-/tmp}}}"
  [ -d "$tmpdir" ] || local tmpdir=~/tmp
  echo "$tmpdir/tmux-$EUID-cpu"
}

get_time() {
  date +%s.%N
}

get_cache_val(){
  local key="$1"
  # seconds after which cache is invalidated
  local timeout="${2:-2}"
  local cache="$(get_tmp_dir)/$key"
  if [ -f "$cache" ]; then
    awk -v cache="$(head -n1 "$cache")" -v timeout=$timeout -v now=$(get_time) \
      'BEGIN {if (now - timeout < cache) exit 0; exit 1}' \
      && tail -n+2 "$cache"
  fi
}

put_cache_val(){
  local key="$1"
  local val="${@:2}"
  local tmpdir="$(get_tmp_dir)"
  [ ! -d "$tmpdir" ] && mkdir -p "$tmpdir" && chmod 0700 "$tmpdir"
  echo "$(get_time)" > "$tmpdir/$key"
  echo -n "$val" >> "$tmpdir/$key"
  echo -n "$val"
}

cached_eval(){
  local command="$1"
  local key="$(basename "$command")"
  local val="$(get_cache_val "$key")"
  if [ -z "$val" ]; then
    put_cache_val "$key" "$($command "${@:2}")"
  else
    echo -n "$val"
  fi
}