import socket
import time
import threading
import copy

KB = 1024
MB = 1024*KB
GB = 1024*MB

def seed_to_data(seed, random=True):
	if random:
		return (seed * 0x31415979 + 1) & 0xffffffff
	else:
		return seed

def check(p1, p2):
	p1 = copy.deepcopy(p1)
	p2 = copy.deepcopy(p2)
	if isinstance(p1, int):
		return 0, 1, int(p1 != p2)
	else:
		if len(p1) >= len(p2):
			ref, res = p1, p2
		else:
			ref, res = p2, p1
		shift = 0
		while((ref[0] != res[0]) and (len(res)>1)):
			res.pop(0)
			shift += 1
		length = min(len(ref), len(res))
		errors = 0
		for i in range(length):
			if ref.pop(0) != res.pop(0):
				errors += 1
		return shift, length, errors

def generate_packet(seed, length):
	r = []
	for i in range(length):
		r.append(seed_to_data(seed, True)%0xff) # XXX FIXME
		seed += 1
	return r, seed

def test(fpga_ip, udp_port, test_size):
	tx_sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
	rx_sock  = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
	rx_sock.bind(("", udp_port))

	def receive():
		rx_seed = 0
		while rx_seed < test_size:
			data, addr = rx_sock.recvfrom(8192)
			rx_packet = []
			for byte in data:
				rx_packet.append(int(byte))
			rx_reference_packet, rx_seed = generate_packet(rx_seed, 1024)
			s, l, e = check(rx_reference_packet, rx_packet)
			print("shift "+ str(s) + " / length " + str(l) + " / errors " + str(e))

	def send():
		tx_seed = 0
		while tx_seed < test_size:
			tx_packet, tx_seed = generate_packet(tx_seed, 1024)
			tx_sock.sendto(bytes(tx_packet), (fpga_ip, udp_port))
			time.sleep(0.001) # XXX: FIXME, Python limitation?

	receive_thread = threading.Thread(target=receive)
	receive_thread.start()

	send_thread = threading.Thread(target=send)
	send_thread.start()

	try:
		send_thread.join(10)
		receive_thread.join(0.1)
	except KeyboardInterrupt:
		pass

test("192.168.1.40", 6000, 128*KB)
test("192.168.1.40", 8000, 128*KB)