#!/opt/lnxall_app/bin/lua

-- created by jiaqiang.ye@lnxall.com
-- Simple command-line utility for EMS2.0 packapp
-- 2024/08/30

local posix = require "posix"
local invoker = require "invoker"

local gfmt = string.format
-- global variables
local g_packdir = '/root/.packapp'
local g_packapp = '/root/.packapp.tar.gz'
local g_packapp_h, g_ipaddr_h = nil, "127.0.0.1"
local g_ipaddr, g_gwsn, g_cmd = nil, nil, nil

local g_sshcmd = { "sshpass", "-p", "lnxall123", "ssh",
	'-oStrictHostKeyChecking=no', '-oUserKnownHostsFile=/dev/null', }

local function validate_args(arg0, arg1, arg2, arg3)
	g_ipaddr, g_gwsn, g_cmd = arg1, arg2, arg3
	if type(g_ipaddr) ~= "string" then g_ipaddr = 'unknown' end
	if not invoker.isipv4(g_ipaddr) then
		io.stderr:write(gfmt("ERROR: invalid IPv4 address specified: %s\n", g_ipaddr))
		io.stderr:flush()
		return false
	end

	if type(g_gwsn) ~= "string" then g_gwsn = "" end
	if #g_gwsn == 0 then
		io.stderr:write(gfmt("ERROR: invalid Gateway SN specified: %s\n", g_gwsn))
		io.stderr:flush()
		return false
	end

	if g_cmd ~= "start" and g_cmd ~= "stop" and g_cmd ~= "query" then
		if type(g_cmd) ~= "string" then g_cmd = "" end
		io.stderr:write(gfmt("ERROR: invalid command for packapp: %s\n", g_cmd))
		io.stderr:flush()
		return false
	end

	if type(arg0) == "string" then arg0 = invoker.realpath(arg0) end
	if type(arg0) == "string" then arg0 = string.match(arg0, "^(.+)/") end
	if type(arg0) ~= "string" or posix.access(arg0) ~= 0 then
		io.stderr:write("ERROR: packapp script not found.\n")
		io.stderr:flush()
		return false
	end
	g_packapp_h = gfmt("%s/packapp.tar.gz", arg0)

	-- initialize environment variables
	posix.setenv("EMS_IP")
	posix.setenv("SSH_CLIENT")
	posix.setenv("SSH_CONNECTION")
	invoker.invoke(invoker.NOSTDIO, "mkdir", "-p",
		"/opt/elect_resources/resources/app/web/dist/exdata")
	return true
end

local function shell_cmd(flag, cmdline)
	if type(flag) ~= "number" then
		flag = invoker.NOSTDIO + invoker.OUTPUT
	end
	local ok, out = invoker.invoke(flag, "/bin/sh", "-c", cmdline)
	return ok, out
end

local function scp_cmd(flag, cmdlist)
	if #cmdlist ~= 0x2 then
		io.stdout:write("ERROR: invalid number of argument for scp.\n")
		io.stdout:flush()
		return nil
	end

	local list, nl = {}, 1
	while type(g_sshcmd[nl]) == "string" do
		if g_sshcmd[nl] == "ssh" then
			list[nl] = "scp"
		else
			list[nl] = g_sshcmd[nl]
		end
		nl = nl + 1
	end

	list[nl] = "-r"; nl = nl + 1
	list[nl] = cmdlist[1]; nl = nl + 1
	list[nl] = gfmt("root@%s:%s", g_ipaddr, cmdlist[2])

	if type(flag) ~= "number" then
		flag = invoker.NOSTDIO + invoker.OUTPUT
	end

	local ok, out = invoker.invoke(flag, list)
	return ok, out
end

local function ssh_cmd(flag, cmdlist)
	local list, nl = {}, 1
	while type(g_sshcmd[nl]) == "string" do
		list[nl] = g_sshcmd[nl]
		nl = nl + 1
	end

	list[nl] = "root@" .. g_ipaddr
	nl = nl + 1
	for _, cmd in ipairs(cmdlist) do
		list[nl] = cmd
		nl = nl + 1
	end

	if type(flag) ~= "number" then
		flag = invoker.NOSTDIO + invoker.OUTPUT
	end

	local ok, out = invoker.invoke(flag, list)
	return ok, out
end

local function check_packapp()
	if not invoker.tcpcheck(g_ipaddr, 22, 2500) then
		io.stderr:write(gfmt("ERROR: gateway %s not online: %s\n", g_ipaddr, g_gwsn))
		io.stderr:flush()
		os.exit(2)
	end

	local md50, md51 = nil, nil
	local okay, output = invoker.invoke(invoker.NOSTDIO + invoker.OUTPUT,
		"md5sum", g_packapp_h)
	if okay == 0 and type(output) == "string" then
		md50 = string.match(output, "^([%d%x]+)")
	end
	if type(md50) ~= "string" or #md50 ~= 32 then
		io.stderr:write(gfmt("ERROR: cannot get md5sum for %s\n", g_packapp_h))
		io.stderr:flush()
		os.exit(3)
	end

	local tried = false
	if g_ipaddr == g_ipaddr_h then
		while true do
			okay, output = shell_cmd(invoker.OUTPUT, gfmt("md5sum %s", g_packapp))
			if okay ~= 0 then output = "" end
			md51 = string.match(output, "^([%d%x]+)")
			if (md51 == md50 or tried) and posix.access(g_packdir) == 0 then
				break
			end
			tried = true
			invoker.invoke(invoker.NOSTDIO, "/bin/sh", "-c", gfmt("rm -rf %s %s", g_packdir, g_packapp))
			invoker.invoke(invoker.NOSTDIO, "cp", "-f", g_packapp_h, g_packapp)
			invoker.invoke(invoker.NOSTDIO, "/bin/sh", "-c", string.format("cd /root && tar -zxf %s", g_packapp))
		end

		if md51 ~= md50 then
			io.stderr:write(gfmt("ERROR: cannot copy packapp to %s, %s\n", g_gwsn, g_ipaddr))
			io.stderr:flush()
			os.exit(4)
		end
		return true
	end

	while true do
		okay, output = ssh_cmd(nil, { [1] = gfmt("md5sum %s", g_packapp) })
		if okay ~= 0 then output = "" end
		md51 = string.match(output, "^([%d%x]+)")
		if md51 == md50 or tried then
			break
		end
		tried = true
		ssh_cmd(nil, { [1] = gfmt("rm -rf %s %s", g_packapp, g_packdir ) })
		if scp_cmd(invoker.NOSTDIO, { [1] = g_packapp_h, [2] = g_packapp }) == 0 then
			ssh_cmd(nil, { [1] = gfmt("cd /root && tar -zxf %s", g_packapp) })
		end
	end

	if md51 ~= md50 then
		io.stderr:write(gfmt("ERROR: cannot copy packapp to %s, %s\n", g_gwsn, g_ipaddr))
		io.stderr:flush()
		os.exit(5)
	end
	return true
end

local function mainfunc_op()
	local cmd = nil
	if g_cmd == "start" then
		cmd = gfmt("%s/cmd_start.sh %s", g_packdir, g_gwsn)
	elseif g_cmd == "stop" then
		cmd = gfmt("%s/cmd_stop.sh %s", g_packdir, g_gwsn)
	elseif g_cmd == "query" then
		cmd = gfmt("%s/cmd_query.sh %s", g_packdir, g_gwsn)
	else
		io.stderr:write(gfmt("ERROR: invalid command: %s\n", g_cmd))
		io.stderr:flush()
		os.exit(5)
	end

	local okay, output = nil, nil
	if g_ipaddr == g_ipaddr_h then
		posix.setenv("EMS_IP", g_ipaddr_h)
		okay, output = shell_cmd(nil, cmd)
	else
		okay, output = ssh_cmd(nil, { [1] = cmd })
	end
	if type(okay) ~= "number" or okay ~= 0 then
		if type(okay) ~= "number" then okay = 90 end
		if type(output) == "string" then
			io.stdout:write(output)
		else
			io.stdout:write(gfmt("ERROR: command '%s' has failed with: %d\n", g_cmd, okay))
		end
		io.stdout:flush()
		os.exit(okay)
	end

	if type(output) ~= "string" or #output == 0 then
		output = gfmt("INFO: command %s executed successfully, without output.", g_cmd)
	end
	io.stdout:write(output)
	io.stdout:flush()
	os.exit(0)
end

if not validate_args(arg[0], arg[1], arg[2], arg[3]) then
	os.exit(1)
end
check_packapp()
mainfunc_op()