#!/bin/bash

shopt -s extglob

declare -a batteries

declare -A custom_icons=(
    ["hid:b0003g0102v0000046Dp00004086"]=" "
    ["hid:b0005g0000v0000054Cp000005C4"]=" "
)

status_by_charge() {
    capacity="$1"

    if [ "$capacity" -ge 95 ]; then
        echo ' '
    elif [ "$capacity" -ge 65 ]; then
        echo ' '
    elif [ "$capacity" -ge 50 ]; then
        echo ' '
    elif [ "$capacity" -gt 20 ]; then
        echo ' '
    fi
}

for battery_path in /sys/class/power_supply/!(AC*); do
    status="$(cat "${battery_path}/status")"
    capacity="$(cat "${battery_path}/capacity")"
    sep=$([ "$1" == "-s" ] && echo " ")
    device_name=$(cat "${battery_path}/device/modalias")

    case "${status}" in
	    "Full") status_symbol=" " ;;
	    "Discharging") status_symbol="$(status_by_charge "${capacity}")" ;;
	    "Charging") status_symbol="󱐥 " ;;
	    "Not charging") status_symbol="󱐤 " ;;
	    "Unknown") status_symbol="󰒲 " ;;
	    *) status_symbol="?? " ;;
    esac

    if [ "$capacity" -eq 100 ]; then
	status_symbol=" "
    elif [ -n "${custom_icons[$device_name]}" ]; then
	status_symbol="${custom_icons["$device_name"]}"
    elif [[ "$status" = "Discharging" && "$capacity" -le 20 ]]; then
	status_symbol="❗"
	[ -n "$sep" ] && sep="" || sep=" ";
    fi

    batteries+=("${status_symbol}${sep}${capacity}%")
done

echo "${batteries[@]}"