parts of probably oh-my-zsh for battery monitoring on macs

battery_prompt.zsh

function battery_pct() {
    typeset -F maxcapacity=$(ioreg -rc "AppleSmartBattery"| grep '^.*"MaxCapacity"\ =\ ' | sed -e 's/^.*"MaxCapacity"\ =\ //')
    typeset -F currentcapacity=$(ioreg -rc "AppleSmartBattery"| grep '^.*"CurrentCapacity"\ =\ ' | sed -e 's/^.*CurrentCapacity"\ =\ //')
    integer i=$(((currentcapacity/maxcapacity) * 100))
    echo $i
}

function battery_pct_remaining() {
    if [[ $(ioreg -rc AppleSmartBattery | grep -c '^.*"ExternalConnected"\ =\ No') -eq 1 ]] ; then
      battery_pct
    else
      echo "External Power"
    fi
}

function battery_pct_prompt () {
    if [[ $(ioreg -rc AppleSmartBattery | grep -c '^.*"ExternalConnected"\ =\ No') -eq 1 ]] ; then
      b=$(battery_pct_remaining)
      if [ $b -gt 50 ] ; then
        color='green'
      elif [ $b -gt 20 ] ; then
        color='yellow'
      else
        color='red'
      fi
      echo "%{$fg[$color]%}[$(battery_pct_remaining)%%]%{$reset_color%}"
    else
      echo "∞"
    fi
}

# RPROMPT='$(battery_pct_prompt)'