local timer = require("gears.timer")
local wibox = require("wibox")

local function readfile(command)
    local file = io.open(command)
    if not file then return nil end
    local text = file:read('*all')
    file:close()
    return text:gsub("^%s*(.-)%s*$", "%1")
end

local battery_widget = wibox.widget{
    markup = 'U00',
    align = 'center',
    widget = wibox.widget.textbox
}

timer = timer({ timeout = 10 })
timer:connect_signal("timeout", function() update() end)
timer:start()

function update()
    local percent = readfile("/sys/class/power_supply/BAT1/capacity")
    local status  = readfile("/sys/class/power_supply/BAT1/status")

    if status == "Charging" then
        prefix = "C"
    elseif status == "Discharging" then
        prefix = "D"
    else
        prefix = "F"
    end

    battery_widget:set_markup(prefix .. percent)
end

update()

return wibox.container.margin(battery_widget, 4)