function batteryInfoUpdate(adapter, warn, widget)
    spacer = " "
    local fcap = io.open("/sys/class/power_supply/"..adapter.."/capacity")
    local fsta = io.open("/sys/class/power_supply/"..adapter.."/status")
    local cap = fcap:read()
    local sta = fsta:read()
    fcap:close()
    fsta:close()

    if sta:match("Charging") then
        state = 1
        icon = "▴"
    else
        state = -1
        icon =  "▾"
    end

    if tonumber(cap) < 10 and warn then
        naughty.notify({ title      = "Battery Warning",
                         text       = "Battery "..adapter.." low at "..cap.."%!",
                         timeout    = 15,
                         position   = "top_right",
                         fg         = beautiful.fg_focus,
                         bg         = beautiful.bg_focus,
                       })
    end
    if tonumber(cap) < 10 then
        color='red'
    elseif tonumber(cap) < 25 then
        color='orange'
    else
        color='green'
    end

    widget:set_markup(spacer.."<span color='"..color.."'>"..icon..cap..'%</span>'..spacer)
end

local wibox = require("wibox")

bat0_widget = wibox.widget.textbox()
bat0_widget:set_align("right")

bat1_widget = wibox.widget.textbox()
bat1_widget:set_align("right")

battery_timer = timer({timeout = 20})
battery_timer:connect_signal("timeout", function()
   batteryInfoUpdate("BAT0", true, bat0_widget)
   batteryInfoUpdate("BAT1", false, bat1_widget)
end)
battery_timer:start()

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