#!/usr/bin/python
'''
 This is a pseudo-server that sends predefined pattern to any connected client.
 It is used to test transport behaviour and throughput.

 If you want to use it with a sketch, connect your PC and Blynk-enabled device
 into the same network and configure Blynk to connect to this pseudo-server:

   IPAddress serv(192,168,0,105); // IP address of your PC
   Blynk.begin(auth, serv, 8888);

 Author:   Volodymyr Shymanskyy
 License:  The MIT license
'''
import select, socket, struct
import os, sys, time, getopt
from threading import Thread

# Configuration options

# Parse command line options
try:
    opts, args = getopt.getopt(sys.argv[1:],
        "hb:p:",
        ["help", "bind=", "port=", "sndbuf=", "rcvbuf=", "nodelay", "sleep=", "qty=", "freq=", "pin=", "dump"])
except getopt.GetoptError:
    print >>sys.stderr, __doc__
    sys.exit(2)

# Default options
HOST = ''       # Bind to all interfaces
PORT = 8888     # Bind to port 8888
NODELAY = 0     # No TCP_NODELAY
SNDBUF = 0      # No SNDBUF override
RCVBUF = 0      # No RCVBUF override
MSG_QTY = 10    # Amount of messages
SLEEP = 1.0     # Wait some time between IO
HW_PIN = "A0"   # Pin #
DUMP = 0

for o, v in opts:
    if o in ("-h", "--help"):
        print __doc__
        sys.exit()
    elif o in ("-b", "--bind"):
        HOST = v
    elif o in ("-p", "--port"):
        PORT = int(v)
    elif o in ("--sndbuf",):
        SNDBUF = int(v)
    elif o in ("--rcvbuf",):
        RCVBUF = int(v)
    elif o in ("--nodelay",):
        NODELAY = 1
    elif o in ("--sleep",):
        SLEEP = float(v)
    elif o in ("--freq",):
        SLEEP = 1.0/float(v)
    elif o in ("--qty",):
        MSG_QTY = int(v)
    elif o in ("--pin",):
        HW_PIN = int(v)
    elif o in ("--dump",):
        DUMP = 1


# Blynk protocol helpers

hdr = struct.Struct("!BHH")

class MsgType:
    RSP    = 0
    LOGIN  = 2
    PING   = 6
    HW     = 20

class MsgStatus:
    OK     = 200

def hw(*args):
    # Convert params to string and join using \0
    data = "\0".join(map(str, args))
    dump("< " + " ".join(map(str, args)))
    # Prepend HW command header
    return hdr.pack(MsgType.HW, 1, len(data)) + data

# Print utilities

start_time = time.time()
def log(msg):
    print "[{:7.3f}] {:}".format(float(time.time() - start_time), msg)

draw_col = 0
def draw(c):
    global draw_col
    if not DUMP:
        sys.stdout.write(c)
        draw_col = (draw_col + 1) % 120
        if draw_col:
            sys.stdout.flush()
        else:
            sys.stdout.write("\n")

def dump(msg):
    if DUMP:
        log(msg)

def receive(sock, length):
	d = []
	l = 0
	while l < length:
		r = sock.recv(length-l)
		if not r:
			return ''
		d.append(r)
		l += len(r)
	return ''.join(d)

# Threads

def readthread(conn, addr):
	global msgs_in, authenticated
	while(msgs_in < MSG_QTY):
		data = receive(conn, hdr.size)
		if not data:
			break
		msg_type, msg_id, msg_len = hdr.unpack(data)
		#dump("Got {0}, {1}, {2}".format(msg_type, msg_id, msg_len))
		if msg_type == MsgType.RSP:
			pass
		elif msg_type == MsgType.LOGIN:
			auth = receive(conn, msg_len)
			log("Auth {0}".format(auth))
			# Send auth OK and pin modes
			conn.sendall(hdr.pack(MsgType.RSP, msg_id, MsgStatus.OK))
			conn.sendall(hw("pm", HW_PIN, "in"))
			authenticated = True
		elif msg_type == MsgType.PING:
			log("Ping")
			# Send Pong
			conn.sendall(hdr.pack(MsgType.RSP, msg_id, MsgStatus.OK))
		elif msg_type == MsgType.HW:
			data = receive(conn, msg_len)
			# Print HW messages (just for fun :)
			draw('v')
			dump("> " + " ".join(data.split("\0")))
			msgs_in += 1
		else:
			log("Unknown msg type")
			break


def writethread(conn, addr):
	global msgs_out, authenticated
	while (msgs_out < MSG_QTY):
		if authenticated:
			conn.sendall(hw("ar", HW_PIN))
			draw('.')
			msgs_out += 1
		time.sleep(SLEEP)


# Main code

serv = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
    # Set SO_REUSEADDR, this is needed to ignore WAIT state on next run
    serv.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    serv.bind((HOST, PORT))
except socket.error as msg:
    log('Bind failed. Error Code: {0}, Msg: {1}'.format(str(msg[0]), msg[1]))
    sys.exit()

serv.listen(1)
log('Listening on port %d' % PORT)

# Wait for clients
#while True:
conn, addr = serv.accept()
log('Connection from {0}:{1}'.format(addr[0], str(addr[1])))
if NODELAY != 0:
	conn.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
if SNDBUF != 0:
	sndbuf = conn.getsockopt(socket.SOL_SOCKET, socket.SO_SNDBUF)
	log('Default SNDBUF %s changed to %s' % (sndbuf, SNDBUF))
	conn.setsockopt(socket.SOL_SOCKET, socket.SO_SNDBUF, SNDBUF)
if RCVBUF != 0:
	rcvbuf = conn.getsockopt(socket.SOL_SOCKET, socket.SO_RCVBUF)
	log('Default RCVBUF %s changed to %s' % (rcvbuf, RCVBUF))
	conn.setsockopt(socket.SOL_SOCKET, socket.SO_RCVBUF, RCVBUF)

proc_start = time.time()
msgs_in = 0
msgs_out = 0
authenticated = False

wt = Thread(target=readthread,  args=(conn, addr))
rt = Thread(target=writethread, args=(conn, addr))

wt.start()
rt.start()

wt.join()
rt.join()

draw("\n")
log("Time %3.4f" % (time.time() - proc_start))
log("Sent {0} messages".format(msgs_out))
log("Recv {0} messages".format(msgs_in))
conn.close()