-- Created by jiaqiang.ye@lnxall.com
-- Simple YOUCAN script demonstration
-- 2023/06/08

-- global variables
local g_gwsn    = "son/of/gun"
local g_topic   = "what/the/hell"
local g_port    = "what/the/fuck"
local g_devsn   = "hello/world"

local function flush_stdio()
	io.stdout:flush()
	io.stderr:flush()
end

function lnxall_initfunc(topic)
	print("Warning, YOUCAN edge script loaded!")
	if type(topic) == "string" then
		g_topic = topic
		print("Using topic prefix: " .. topic)
		local gwsn, port, devsn = string.match(topic, "^ipc/([^/]+)/([^/]+)/device/([^/]+)/")
		if type(devsn) == "string" then
			g_gwsn, g_port, g_devsn = gwsn, port, devsn
			print("Using GWSN: " .. gwsn)
			print("Using connection port: " .. port)
			print("Using DEVSN: " .. devsn)
		end
	end
	flush_stdio()
	return 0
end

local function pack_json(tagnode, svrname, reper)
	local payload = {
		["sn"] = g_devsn,
		["time"] = os.time(),
		["identifier"] = svrname,
		["data_type"] = 2, ["mi"] = 0,
		["report_period"] = type(reper) == "number" and reper or 0,
		["port"] = g_port,
		["report"] = 0,
		["res"] = 0,
		["tag_node"] = tagnode,
	}
	return cjson.encode(payload)
end

-- input is a Lua table
-- output should be a (JSON) string
function fu_autoreport(tags)
	print("Entering function fu_autoreport", type(tags))
	flush_stdio()
	return cjson.encode(tags)
end

-- input is a JSON string
-- output should be a JSON string
function fd_autoreport(tags)
	print("Entering function fd_autoreport", type(tags))
	flush_stdio()
	return tags
end

function fu_candown1(tags)
	print("Entering function fu_candown1", type(tags))
	io.stdout:flush()
	local out = {}
	out[#out + 1] = g_topic .. "/candown1"
	out[#out + 1] = pack_json(cjson.encode(tags), 'candown1')
	out[#out + 1] = g_topic .. "/autoreport"
	out[#out + 1] = pack_json('{"rval_0":1949,"rval_1":1978,"rval_2":2001,"rval_3":2023}', 'autoreport')
	return table.concat(out, string.char(0x1b))
end

function fd_candown1(tags)
	print("Entering function fd_candown1", type(tags))
	flush_stdio()
	return tags
end