local wibox = require("wibox")
local widgets = require("util.widgets")


function linux_ram_usage(widget)
	-- read meminfo
	local meminfof = io.open("/proc/meminfo")

	local total   = meminfof:read():match("%d+")
	local free    = meminfof:read():match("%d+")

	meminfof:read() -- memavailable not used

	local buffers = meminfof:read():match("%d+")
	local cached  = meminfof:read():match("%d+")

	meminfof:close()

	-- calc
	if total == nil then
		return
	end

	local used = (total - free - buffers - cached) * 100 / total

	widget:set_text(math.floor(used))
end

-- return correct widget for os
if osname == "Linux" then
	return widgets.watchfn(linux_ram_usage, 5)
end

return wibox.widget.textbox("unsupported os")