Acpitools-based battery widget

And here's my personal battery widget. It's using acpitool as a battery information source (so install that first), and uses colors for an added touch (you might need to change the specific colors for contrastual reasons). Other than that, it's heavily based on Battery Widget using powersave.

mybattmon = widget({ type = "textbox", name = "mybattmon", align = "right" })
function battery_status ()
    local output={} --output buffer
    local fd=io.popen("acpitool -b", "r") --list present batteries
    local line=fd:read()
    while line do --there might be several batteries.
        local battery_num = string.match(line, "Battery \#(%d+)")
        local battery_load = string.match(line, " (%d*\.%d+)%%")
        local time_rem = string.match(line, "(%d+\:%d+)\:%d+")
	local discharging
	if string.match(line, "discharging")=="discharging" then --discharging: always red
		discharging="<span color=\"#CC7777\">"
	elseif tonumber(battery_load)>85 then --almost charged
		discharging="<span color=\"#77CC77\">"
	else --charging
		discharging="<span color=\"#CCCC77\">"
	end
        if battery_num and battery_load and time_rem then
            table.insert(output,discharging.."BAT#"..battery_num.." "..battery_load.."%% "..time_rem.."</span>")
        elseif battery_num and battery_load then --remaining time unavailable
            table.insert(output,discharging.."BAT#"..battery_num.." "..battery_load.."%%</span>")
        end --even more data unavailable: we might be getting an unexpected output format, so let's just skip this line.
        line=fd:read() --read next line
    end
    return table.concat(output," ") --FIXME: better separation for several batteries. maybe a pipe?
end
mybattmon.text = " " .. battery_status() .. " "
my_battmon_timer=timer({timeout=30})
my_battmon_timer:add_signal("timeout", function()
    --mytextbox.text = " " .. os.date() .. " "
    mybattmon.text = " " .. battery_status() .. " "
end)
my_battmon_timer:start()

Don't forget to register mybattmon.