local awful = require("awful")
local beautiful = require("beautiful")
local wibox = require("wibox")

local _M = {}

function _M.update(stdout)
	local bat_now = {
		present = "N/A",
		state = "N/A",
		warninglevel = "N/A",
		energy = "N/A",
		energyfull = "N/A",
		energyrate = "N/A",
		voltage = "N/A",
		percentage = "N/A",
		capacity = "N/A",
		icon = "N/A",
	}

	for k, v in stdout:gmatch("([%a]+[%a|-]+):%s*([%a|%d|']+[,|%a|%d|'|-]+)") do
		if k == "present" then
			bat_now.present = v
		elseif k == "state" then
			bat_now.state = v
		elseif k == "warning-level" then
			bat_now.warninglevel = v
		elseif k == "energy" then
			bat_now.energy = v:gsub(",", ".") -- Wh
		elseif k == "energy-full" then
			bat_now.energyfull = v:gsub(",", ".") -- Wh
		elseif k == "energy-rate" then
			bat_now.energyrate = v:gsub(",", ".") -- W
		elseif k == "voltage" then
			bat_now.voltage = v:gsub(",", ".") -- V
		elseif k == "percentage" then
			bat_now.percentage = tonumber(v) -- %
		elseif k == "capacity" then
			bat_now.capacity = v:gsub(",", ".") -- %
		elseif k == "icon-name" then
			bat_now.icon = v
		end
	end

	return bat_now
end

function _M.get(show_percentage)
    _M.show_percentage = show_percentage or true
	local battery = awful.widget.watch(
		{
			awful.util.shell,
			"-c",
			"upower -i /org/freedesktop/UPower/devices/battery_BAT0 | sed -n '/present/,/icon-name/p'",
		},
		1,
		function(widget, stdout)
			local bat_now = _M.update(stdout)

            local icon = wibox.widget.imagebox(beautiful.battery_icon(bat_now.icon) or beautiful.battery_icon_full)
            local text = wibox.widget.textbox(bat_now.percentage .. "%")

            widget.children = {
                (_M.show_percentage and text) or wibox.widget.textbox(),
                icon
            }
		end,
        wibox.widget {
            layout = wibox.layout.fixed.horizontal,
        }
	)

    battery.toggle_percentage = function()
        _M.show_percentage = not _M.show_percentage
        battery:emit_signal("widget::redraw_needed")
    end

	return battery
end

return setmetatable({}, {
	__call = function(_, ...)
		return _M.get(...)
	end,
})