Apple MacBook macOS Critical Battery Warning at 5% or less (`/usr/local/bin/*`)

battcritical.sh

#!/bin/bash

# Initialize the last_battery_percentage
last_battery_percentage=-1

while true; do
  # Get the current battery percentage
  battery_percentage=$(pmset -g batt | grep -o '[0-9]\+%' | tr -d '%')

  # Only display the dialog if the new battery percentage is 5% or less
  if [[ $battery_percentage -le 5 ]]; then

    # Only display the dialog if the computer is on battery power
    power_source=$(pmset -g batt | grep -o 'discharging')
    if [[ $power_source == "discharging" ]]; then

      # Check if the battery percentage has changed
      if [[ $last_battery_percentage -ne $battery_percentage ]]; then
        # afplay /System/Library/Sounds/Glass.aiff > /dev/null 2>&1
        osascript <<EOF > /dev/null 2>&1
beep
display alert "Battery Level: ${battery_percentage}%" message "Connect a charger soon!" as critical giving up after 60
EOF
        # Update the last battery percentage
        last_battery_percentage=$battery_percentage
      fi

    else
      # Reset the last battery percentage (shows message again if unplugged)
      last_battery_percentage=-1
    fi

  fi

  # Sleep for 1 second before checking again
  sleep 1
done

login-scripts.sh

nohup battcritical &
nohup osascript -e 'tell application "Terminal" to quit' &