#!/usr/bin/env python
#
# Copyright 2005, 2006, 2007 Free Software Foundation, Inc.
# 
# This file is part of GNU Radio
# 
# GNU Radio is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3, or (at your option)
# any later version.
# 
# GNU Radio is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with GNU Radio; see the file COPYING.  If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
# 

from gnuradio import gr, gru, modulation_utils
from gnuradio import usrp
from gnuradio import eng_notation
from gnuradio.eng_option import eng_option
from optparse import OptionParser

import random
import time
import struct
import sys
import string
import time
import timing

# from current dir
from receive_path import receive_path
from transmit_path import transmit_path
import fusb_options

#import os 
#print os.getpid()
#raw_input('Attach and press enter')

class my_top_block(gr.top_block):
    def __init__(self, modulator, demodulator, rx_callback, options):
        gr.top_block.__init__(self)
	self.rxpath = receive_path(demodulator, rx_callback, options)
	self.connect(self.rxpath)
        self.txpath = transmit_path(modulator, options)
        self.connect(self.txpath)

# /////////////////////////////////////////////////////////////////////////////
#                                   main
# /////////////////////////////////////////////////////////////////////////////

def main():

    global n_rcvd, pktno
    n_rcvd = 0
    global flag 
    flag = True

    def send_pkt(payload='', eof=False):
        return tb.txpath.send_pkt(payload, eof)

    def rx_callback(ok, payload):
        global n_rcvd, flag, pktno
        (n_rcvd,) = struct.unpack('!h', payload[0:2])
        data = payload[2:]
        if ok:
	    if n_rcvd == pktno:
	        if(data == 'ACK'):
		    print "pkt reached"
	        elif(data == 'NACK'):
		    print "pkt lost"
		    pktno -= 1
		
	    flag = True
	     
        print "ok = %r, payload = '%s'" % (ok, payload)
	
    mods = modulation_utils.type_1_mods()
    demods = modulation_utils.type_1_demods()

    parser = OptionParser(option_class=eng_option, conflict_handler="resolve")
    expert_grp = parser.add_option_group("Expert")

    parser.add_option("-m", "--modulation", type="choice", choices=mods.keys(),
                      default='gmsk',
                      help="Select modulation from: %s [default=%%default]"
                            % (', '.join(mods.keys()),))

    parser.add_option("-s", "--size", type="eng_float", default=1500,
                      help="set packet size [default=%default]")
    parser.add_option("-M", "--megabytes", type="eng_float", default=1.0,
                      help="set megabytes to transmit [default=%default]")
    parser.add_option("","--discontinuous", action="store_true", default=False,
                      help="enable discontinous transmission (bursts of 5 packets)")
    parser.add_option("","--from-file", default=None,
                      help="use file for packet contents")
    
    parser.add_option("-m", "--modulation", type="choice", choices=demods.keys(),
                      default='gmsk',
                      help="Select modulation from: %s [default=%%default]"
                            % (', '.join(demods.keys()),))    

    receive_path.add_options(parser, expert_grp)
    transmit_path.add_options(parser, expert_grp)

    for mod in mods.values():
        mod.add_options(expert_grp)

    fusb_options.add_options(expert_grp)
    (options, args) = parser.parse_args ()

    if len(args) != 0:
        parser.print_help()
        sys.exit(1)

    if options.tx_freq is None:
        sys.stderr.write("You must specify -f FREQ or --freq FREQ\n")
        parser.print_help(sys.stderr)
        sys.exit(1)

    if options.from_file is not None:
        source_file = open(options.from_file, 'rb')

    # build the graph
    tb = my_top_block(mods[options.modulation], demods[options.modulation], rx_callback, options)

    r = gr.enable_realtime_scheduling()
    if r != gr.RT_OK:
        print "Warning: failed to enable realtime scheduling"

    tb.start()                       # start flow graph
        
    # generate and send packets
    nbytes = int(1e6 * options.megabytes)
    n = 0
    pktno = 0
    pkt_size = int(options.size)
    nil = 0
    tim = 0
    count = 0

    while n < nbytes:
        if options.from_file is None:
            data = (pkt_size - 2) * chr(pktno & 0xff) 
        elif flag != False and count < 5:
            data = source_file.read(pkt_size - 2)
            #print "Length = " 
            #print len(data)
            if data == '':
                print "Eof"
		#sys.exit(1)
		bill()
                #break;
            if len(data) < (pkt_size - 2):
                print "End of file is reached"
                #break;
	else:
	    count = 0

        payload = struct.pack('!H', pktno & 0xffff) + data
        send_pkt(payload)
	flag = False
	count += 1
	#tim = 0
	time_to_wait = 3000
	timing.start()
	while flag == False:
	    time.sleep(.01)
	    timing.finish()
	    #print timing.finish()
	    if timing.milli() > time_to_wait:
		pktno -= 1
		print "time over"
		break;
	    #time.sleep(1)
	    #tim += 1
		
        #n += len(payload)
        #nil += len(payload)-2
        #print nil
        if options.discontinuous and pktno % 5 == 4:
            time.sleep(1)
        pktno += 1
    
    #payload = struct.pack('!H', pktno & 0xffff) + data    
    #send_pkt(payload, eof=True)
    #temp_data = 'End_of_file'
    #payload = struct.pack('!H', pktno & 0xffff) + temp_data
    #send_pkt(payload)
    ###send_pkt(eof=True)
    sys.exit(1)
    
    tb.wait()                       # wait for it to finish

if __name__ == '__main__':
    try:
        main()
    except KeyboardInterrupt:
        pass