--      ██████╗  █████╗ ████████╗████████╗███████╗██████╗ ██╗   ██╗
--      ██╔══██╗██╔══██╗╚══██╔══╝╚══██╔══╝██╔════╝██╔══██╗╚██╗ ██╔╝
--      ██████╔╝███████║   ██║      ██║   █████╗  ██████╔╝ ╚████╔╝
--      ██╔══██╗██╔══██║   ██║      ██║   ██╔══╝  ██╔══██╗  ╚██╔╝
--      ██████╔╝██║  ██║   ██║      ██║   ███████╗██║  ██║   ██║
--      ╚═════╝ ╚═╝  ╚═╝   ╚═╝      ╚═╝   ╚══════╝╚═╝  ╚═╝   ╚═╝

-------------------------------------------------
-- Battery Widget for Awesome Window Manager
-- Shows the battery status using the ACPI tool
-- More details could be found here:
-- https://github.com/streetturtle/awesome-wm-widgets/tree/master/battery-widget

-- @author Pavel Makhov
-- @copyright 2017 Pavel Makhov
-------------------------------------------------

-- ===================================================================
-- Initialization
-- ===================================================================

local awful = require("awful")
local watch = require("awful.widget.watch")
local wibox = require("wibox")
local clickable_container = require("widgets.clickable-container")
local gears = require("gears")
local dpi = require("beautiful").xresources.apply_dpi

local PATH_TO_ICONS = os.getenv("HOME") .. "/.config/awesome/icons/battery/"

-- ===================================================================
-- Widget Creation
-- ===================================================================

local widget = wibox.widget({
	{
		id = "icon",
		widget = wibox.widget.imagebox,
		resize = true,
	},
	layout = wibox.layout.fixed.horizontal,
})

local widget_button = clickable_container(wibox.container.margin(widget, dpi(7), dpi(7), dpi(7), dpi(7)))
widget_button:buttons(gears.table.join(awful.button({}, 1, nil, function()
	awful.spawn(apps.power_manager)
end)))

-- Alternative to naughty.notify - tooltip. You can compare both and choose the preferred one
local battery_popup = awful.tooltip({
	objects = { widget_button },
	mode = "outside",
	align = "left",
	referred_positions = { "right", "left", "top", "bottom" },
})

local function show_battery_warning()
	naughty.notify({
		icon = PATH_TO_ICONS .. "battery-alert.svg",
		icon_size = dpi(48),
		text = "Huston, we have a problem",
		title = "Battery is dying",
		timeout = 5,
		hover_timeout = 0.5,
		position = "top_right",
		bg = "#d32f2f",
		fg = "#EEE9EF",
		width = 248,
	})
end

local last_battery_check = os.time()

watch(
	"bash -c 'acpi -i | grep -E \"^Battery [0-9]+: ([^%]+%)$|(.+remaining)$|(.+charged)$\" --color=never'",
	1,
	function(_, stdout)
		local battery_info = {}
		local capacities = {}
		for s in stdout:gmatch("[^\r\n]+") do
			local status, charge_str, _ = string.match(s, ".+: (%a+), (%d?%d?%d)%%,?.*")
			if status ~= nil then
				table.insert(battery_info, { status = status, charge = tonumber(charge_str) })
			else
				local cap_str = string.match(s, ".+:.+last full capacity (%d+)")
				table.insert(capacities, tonumber(cap_str))
			end
		end

		local capacity = 0
		for _, cap in ipairs(capacities) do
			capacity = capacity + cap
		end

		local charge = 0
		local status
		for i, batt in ipairs(battery_info) do
			if batt.charge >= charge then
				status = batt.status -- use most charged battery status
				-- this is arbitrary, and maybe another metric should be used
			end

			charge = charge + batt.charge * capacities[i]
		end
		charge = charge / capacity

		if charge >= 0 and charge < 15 then
			if status ~= "Charging" and os.difftime(os.time(), last_battery_check) > 300 then
				-- if 5 minutes have elapsed since the last warning
				last_battery_check = os.time()

				show_battery_warning()
			end
		end

		local battery_icon_name = "battery"

		if status == "Charging" or status == "Full" then
			battery_icon_name = battery_icon_name .. "-charging"
		end

		local rounded_charge = math.floor(charge / 10) * 10
		if rounded_charge == 0 then
			battery_icon_name = battery_icon_name .. "-outline"
		elseif rounded_charge ~= 100 then
			battery_icon_name = battery_icon_name .. "-" .. rounded_charge
		end

		widget.icon:set_image(PATH_TO_ICONS .. battery_icon_name .. ".svg")
		-- Update popup text
		battery_popup.text = string.gsub(stdout, "\n$", "")
		collectgarbage("collect")
	end,
	widget
)

return widget_button
