#!/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, demodulator, modulator, 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
# /////////////////////////////////////////////////////////////////////////////

global n_rcvd, n_right

def main():
    global n_rcvd, n_right, dest_file
    global rcv_flag

    n_rcvd = 0
    n_right = 0
    rcv_flag = True

    def send_pkt(payload='', eof=False):
        return tb.txpath.send_pkt(payload, eof)
    
    def rx_callback(ok, payload):
        global n_rcvd, n_right, dest_file
        global rcv_flag
        send_data = 'ACK'
        (pktno,) = struct.unpack('!H', payload[0:2])
        data = payload[2:]
        n_rcvd += 1
        if ok:
	    if n_right == pktno:
            	n_right += 1
	        dest_file.write(data)
		dest_file.flush()
            
            payload = struct.pack('!H', n_rcvd & 0xffff) + send_data
	    #payload = struct.pack('!H', n_right & 0xffff) + send_data
            send_pkt(payload)
	    print "ACK"
            #rcv_flag = False
	else:
	   payload = struct.pack('!H', n_rcvd & 0xffff) + 'NACK'
           send_pkt(payload)
	   print "NACK"
	   
	rcv_flag = False

        print "ok = %5s  pktno = %4d  n_rcvd = %4d  n_right = %4d" % (
            ok, pktno, n_rcvd, n_right)
        #print data

    demods = modulation_utils.type_1_demods()
    mods = modulation_utils.type_1_mods()

    # Create Options Parser:
    parser = OptionParser (option_class=eng_option, conflict_handler="resolve")
    expert_grp = parser.add_option_group("Expert")

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

    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")

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


    for mod in demods.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.stderr)
        sys.exit(1)

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


    dest_file = open("dest_test_new.jpg", 'wb')
    # build the graph
    tb = my_top_block(demods[options.modulation], mods[options.modulation], rx_callback, options)

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

    time_to_wait = 4000 # wait for next frame. O/w 
    tb.start()        # start flow graph
    timing.start()
    if rcv_flag == False:
        timing.finish()
        if timing.milli > time_to_wait:
            dest_file.close()
            sys.exit()
        
    tb.wait()         # wait for it to finish

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