battery-discharging

#!/usr/bin/env bash
set -e
set +xv

VERSION="v1.0.3"
BATTERY_STATUS="Discharging"
BEEP_WAIT_SECONDS="2.5"
POWER_SUPPLY_PATH="/sys/class/power_supply"
SOUND_DURATION="0.2"
SOUND_FREQUENCY="2000"
TEST_TIMES="3"

display_help() {
  echo ""
  echo "USAGE:"
  echo "  battery-discharging [OPTIONS]"
  echo ""
  echo "DESCRIPTION"
  echo "  Command-line tool that makes a sound whenever the computer's battery is not"
  echo "  connected to electrical power."
  echo ""
  echo "  RECOMMENDATION:"
  echo "    Run this tool in the background so that it detects the absence of electrical"
  echo "    power in the battery at all times."
  echo "    For example: 'battery-discharging &'"
  echo ""
  echo "ARGS:"
  echo "  None."
  echo ""
  echo "OPTIONS:"
  echo "  ┌──────┬──────────────────┬──────────────────────────────────────────────────┐"
  echo "  │ Abbr │       Long       │                     Information                  │"
  echo "  ╞══════╪══════════════════╪══════════════════════════════════════════════════╡"
  echo "  │  -d  │ --duration       │ The duration of the beep.                        │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     integer | float                    │"
  echo "  │      │                  │   - Values:   1                                  │"
  echo "  │      │                  │   - Default:  0.2                                │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -f  │ --frequency      │ The frequency of the beep. Low values are low    │"
  echo "  │      │                  │ sounds, and high values are high sounds.         │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     integer                            │"
  echo "  │      │                  │   - Values:   1500                               │"
  echo "  │      │                  │   - Default:  2000                               │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -h  │ --help           │ Display information for this command and exit.   │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     none                               │"
  echo "  │      │                  │   - Values:   none                               │"
  echo "  │      │                  │   - Default:  none                               │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -p  │ --path           │ The path of the directory where the list of power│"
  echo "  │      │                  │ supply devices is located.                       │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     string                             │"
  echo "  │      │                  │   - Values:   /dev/battery                       │"
  echo "  │      │                  │   - Default:  /sys/class/power_supply            │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -s  │ --status         │ Linux stores the battery status in a file.       │"
  echo "  │      │                  │ Text that must match within the battery file.    │"
  echo "  │      │                  │ The text is not case-sensitive.                  │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     string                             │"
  echo "  │      │                  │   - Values:   Disconnected                       │"
  echo "  │      │                  │   - Default:  Discharging                        │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -t  │ --test           │ Try the beep a certain number of times and exit. │"
  echo "  │      │                  │ This is used with the '--duration', '--frequency'│"
  echo "  │      │                  │ and '--wait' options.                            │"
  echo "  │      │                  │ Note: This option must go at the end of the other│"
  echo "  │      │                  │ options. Otherwise, the other options will have  │"
  echo "  │      │                  │ no effect.                                       │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     integer                            │"
  echo "  │      │                  │   - Values:   15                                 │"
  echo "  │      │                  │   - Default:  3                                  │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -V  │ --version        │ Display the version of this tool along with the  │"
  echo "  │      │                  │ project information and exit.                    │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     none                               │"
  echo "  │      │                  │   - Values:   none                               │"
  echo "  │      │                  │   - Default:  none                               │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │      │ --version-simple │ Display the version of this tool and exit.       │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     none                               │"
  echo "  │      │                  │   - Values:   none                               │"
  echo "  │      │                  │   - Default:  none                               │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -w  │ --wait           │ Waiting time between one beep and another.       │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     integer | float                    │"
  echo "  │      │                  │   - Values:   5                                  │"
  echo "  │      │                  │   - Default:  2.5                                │"
  echo "  └──────┴──────────────────┴──────────────────────────────────────────────────┘"
  echo ""
  echo "EXAMPLES:"
  echo "  - Default values."
  echo "    - Commands:"
  echo "        battery-discharging"
  echo "        battery-discharging &"
  echo ""
  echo "  - Test the beep six times with a frequency of 1250, a duration of 0.5 seconds,"
  echo "    and a wait between each beep of 1.3 seconds."
  echo "    - Note: This option must go at the end of the other options. Otherwise, the"
  echo "      other options will have no effect."
  echo "    - Commands:"
  echo "        battery-discharging --frequency 1250 --duration 0.5 --wait 1.3 --test 6"
  echo "        battery-discharging -f 1250 -d 0.5 -w 1.3 -t 6"
  echo ""
  echo "  - Assigns the frequency of the beep."
  echo "    - Commands:"
  echo "        battery-discharging --frequency 400"
  echo "        battery-discharging -f 400"
  echo ""
  echo "  - Assigns the duration of the beep."
  echo "    - Commands:"
  echo "        battery-discharging --duration 1.2"
  echo "        battery-discharging -d 1.2"
  echo ""
  echo "  - Assign the wait between one beep and another."
  echo "    - Commands:"
  echo "        battery-discharging --wait 7.7"
  echo "        battery-discharging -w 7.7"
  echo ""
  echo "  - Assign the path where the Linux files related to the power supply are"
  echo "    located."
  echo "    - Commands:"
  echo "        battery-discharging --path /udev/system/power_supply"
  echo "        battery-discharging -p /udev/system/power_supply"
  echo ""
  echo "  - Assign the text that must be matched within the Linux file related to the"
  echo "    power supply."
  echo "    - Commands:"
  echo "        battery-discharging --status 'Not connected'"
  echo "        battery-discharging -s 'Not connected'"
  echo ""
  echo "  - Multiple options can be used multiple times. It will only take the last"
  echo "    value of each option."
  echo "    - In this example it will set the frequency to 15."
  echo "        battery-discharging --frequency 321 --frequency 123456 --frequency 15"
  echo ""
  display_version
  echo ""
  echo ""
}

display_version() {
  echo "VERSION:"
  echo "  ${VERSION}"
  echo ""
  echo "  Source: https://github.com/airvzxf/archlinux-battery-discharging/"
  echo "  Author: Israel Roldan"
  echo "    Email: israel.alberto.rv@gmail.com"
  echo "    GitHub: @airvzxf"
  echo "    Twitter: @IsraelAlbert_RV"
  echo "    Website: https://www.rovisoft.net/"
}

display_version_simple() {
  echo "${VERSION}"
}

parse_arguments() {
  while [[ ${#} -gt 0 ]]; do
    case "${1}" in
      -d | --duration)
        # Remove this argument.
        shift
        SOUND_DURATION="${1}"
        # Remove this value.
        shift
        ;;
      -f | --frequency)
        # Remove this argument.
        shift
        SOUND_FREQUENCY="${1}"
        # Remove this value.
        shift
        ;;
      -h | --help)
        display_help
        exit 0
        ;;
      -p | --path)
        # Remove this argument.
        shift
        POWER_SUPPLY_PATH="${1}"
        # Remove this value.
        shift
        ;;
      -s | --status)
        # Remove this argument.
        shift
        BATTERY_STATUS="${1}"
        # Remove this value.
        shift
        ;;
      -t | --test)
        # Remove this argument.
        shift
        TEST_TIMES="${1}"
        # Remove this value.
        shift
        test_sound
        exit 0
        ;;
      -V | --version)
        display_version
        exit 0
        ;;
      --version-simple)
        display_version_simple
        exit 0
        ;;
      -w | --wait)
        # Remove this argument.
        shift
        BEEP_WAIT_SECONDS="${1}"
        # Remove this value.
        shift
        ;;
      --* | -* | *)
        echo "Unknown option ${1}."
        echo "Review the help with this command:"
        echo "  battery-discharging -h"
        exit 1
        ;;
    esac
  done
}

beep_now() {
  speaker-test --test sine --nloops 1 --frequency "${SOUND_FREQUENCY}" 1> /dev/null &

  local pid
  pid="${!}"
  sleep "${SOUND_DURATION}s"
  kill -9 "${pid}"
  wait "${pid}" 2> /dev/null || true
}

test_sound() {
  local count
  for ((count=1; count <= TEST_TIMES; count++)); do
    echo "Test #${count}"
    beep_now
    sleep "${BEEP_WAIT_SECONDS}s"
  done
  echo "The test has ended."
}

battery_discharging() {
  ls "${POWER_SUPPLY_PATH}" 1> /dev/null 2> /dev/null || {
    echo "ERROR: Trying to display the power supply directory: ${POWER_SUPPLY_PATH}"
    exit 1
  }

  declare -a batteries=()
  local power_supply
  for power_supply in "${POWER_SUPPLY_PATH}"/*; do
    if [[ ${power_supply} =~ (CMB|BAT|battery) ]]; then
      batteries+=("${power_supply}")
    fi
  done

  if [ -z "${batteries[*]}" ]; then
    echo "ERROR: There is no battery in this device."
    echo "- Display the power supply directory: ${POWER_SUPPLY_PATH}"
    ls "${POWER_SUPPLY_PATH}"
    return 1
  fi

  local battery
  while true; do
    for battery in "${batteries[@]}"; do
      if grep --quiet --ignore-case "${BATTERY_STATUS}" "${battery}/status"; then
        beep_now
      fi
    done
    sleep "${BEEP_WAIT_SECONDS}s"
  done
}

main() {
  parse_arguments "${@}"
  battery_discharging
}

main "${@}"