extends Node

export(String) var server : String = "smtp.gmail.com" 
export(int) var port : int = 465
export(String) var user : String = ""
export(String) var password : String = ""
export(String) var email_address : String = "mail.smtp.localhost"
export(String) var client_address : String = "client.example.com"
export(int) var max_retries : int = 5
export(int) var delay_time : int = 250

var _socket_original : StreamPeer = null
var _socket : StreamPeer = null
var _packet_in : String = ""
var _packet_out : String = ""

enum SMTPStatus {
	OK,
	WAITING,
	NO_RESPONSE,
	UNHANDLED_REPONSE
}

var _current_status : int = 0

var _thread : Thread = null

var _auth_login_base64 : String = ""
var _auth_pass_base64 : String = ""

func _ready():
	if user != "":
		_auth_login_base64 = Marshalls.raw_to_base64(user.to_ascii())
		
	if password != "":
		_auth_pass_base64 = Marshalls.raw_to_base64(password.to_ascii())
  
func send_mail(address, subject, data):
	_thread = Thread.new()
	_thread.start(self, "_thread_deliver", [address, subject, data])

func _thread_deliver(user_data):
	var address : String = user_data[0]
	var subject : String = user_data[1]
	var data : String = user_data[2]
	
	var r_code : int
	r_code = open_socket()
	if r_code == OK:
		r_code = wait_answer()
		
#	if r_code == OK:
#		emit_signal("SMTP_connected")
#		r_code = send("ciao") # needed because some SMTP servers return error each first command

	if r_code == OK:
		r_code = mail_hello()
	if r_code == OK:
		print("SMTP_working")
		close_socket()
		return
		r_code = mail_auth()
	if r_code == OK:
		r_code = mail_from(address)
	if r_code == OK:
		r_code = mail_to(address)
	if r_code == OK:
		r_code = mail_data(data, address, subject)
	if r_code == OK:
		print("process OK")
	if r_code == OK:
		r_code = mail_quit()
	close_socket()
	if r_code == OK:
		display("All done")
	else:
		display("ERROR " + str(r_code))
	return r_code


func open_socket():
	var error : int

	if _socket_original == null:
		_socket_original = StreamPeerTCP.new()
		error = _socket_original.connect_to_host(server,port)
		
		_socket = StreamPeerSSL.new()
		_socket.connect_to_stream(_socket_original, true, server)

	display(["connecting server...",server,error])

	if error > 0:
		var ip = IP.resolve_hostname(server)
		error=_socket.connect_to_host(ip,port)
		display(["trying IP ...",ip,error])

	for i in range(1,max_retries):
		print("RETRIES" + str(_socket.get_status()))
		
#		if _socket.get_status() == _socket.STATUS_ERROR:
#			d.display("Error while requesting connection")
#			break
#		elif _socket.get_status() == _socket.STATUS_CONNECTING:
#			d.display("connecting...")
#			break

		if _socket.get_status() == _socket.STATUS_CONNECTED:
			display("connection up")
			print("CONNECTED")
			break
			
		OS.delay_msec(delay_time)
		
	return error

func close_socket():
	_socket_original.disconnect_from_host()

func send(data1,data2=null,data3=null):
	return send_only(data1,data2,data3)

func send_only(data1,data2=null,data3=null):
	var error = 0
	_packet_out = data1
	if data2 != null:
		_packet_out = _packet_out + " " + data2
	if data3 != null:
		_packet_out = _packet_out + " " + data3
	display(["send",_packet_out])
	_packet_out = _packet_out + "\n"

	error=_socket.put_data(_packet_out.to_utf8())
	if error == null:
		error = "NULL"
		
	display(["send","r_code",error])
	
	return error

func wait_answer(succesful=""):
	_current_status= SMTPStatus.WAITING
	display(["waiting response from server..."])

	_packet_in = ""
	OS.delay_msec(delay_time)
	for i in range(1,max_retries):
		_socket.poll()
		var bufLen = _socket.get_available_bytes()
		if bufLen > 0:
			display(["bytes buffered",String(bufLen)])
			_packet_in=_packet_in + _socket.get_utf8_string(bufLen)
			display(["receive",_packet_in])
			
			break
		else:
			OS.delay_msec(delay_time)
	if _packet_in != "":
		_current_status= SMTPStatus.OK
		if parse_packet_in(succesful) != OK:
			_current_status=SMTPStatus.UNHANDLED_REPONSE
	else:
		_current_status = SMTPStatus.NO_RESPONSE
	return _current_status


func parse_packet_in(strcompare):
	if strcompare == "":
		return OK
	if _packet_in.left(strcompare.length())==strcompare:
		return OK
	else:
		return FAILED

func mail_hello():
	var r_code : int = send("HELO", client_address)
	wait_answer()
	r_code= send("EHLO", client_address)
	r_code= wait_answer("250")
	return r_code

func mail_auth():
	var r_code : int =send("AUTH LOGIN")
	r_code=wait_answer("334")
	
	#print("mail_auth()  , AUTH LOGIN ", r_code) 

	if r_code == OK:
		r_code=send(_auth_login_base64)
		
	r_code = wait_answer("334")
	
	#print("mail_auth()  , username ", r_code)
	
	if r_code == OK:
		r_code=send(_auth_pass_base64)
		
	r_code = wait_answer("235")
	#print("mail_auth()  , password ", r_code)
	display(["r_code auth:", r_code])
	
	return r_code

func mail_from(data):
	var r_code=send("MAIL FROM:",bracket(data))
	r_code = wait_answer("250")
	return r_code

func mail_to(data):
	var r_code=send("RCPT TO:",bracket(data))
	r_code = wait_answer("250")
	return r_code
	

func mail_data(data=null,from=null,subject=null):
	var corpo : String = ""
	for i in data:
		corpo = corpo + i  + "\r\n"
	corpo=corpo + "."
	var r_code=send("DATA") 
	r_code=wait_answer("354")
#	if r_code == OK and from != null:
#		r_code=send("FROM: ",bracket(from))
	if r_code == OK and subject != null:
		r_code=send("SUBJECT: ",subject)
	if r_code == OK and data != null:
		r_code=send(corpo)
	r_code =wait_answer("250")
	return r_code

func mail_quit():
	return send("QUIT")

func bracket(data):
	return "<"+data+">"

func _on_Button_pressed() -> void:
	send_mail("", "TEST SUBJECT", "TEST MSG!")

var debug = true
func display(data):
	if debug == true:
		print("debug: ",data)