#!/usr/bin/python

# IgorplugUDP.py -- python transcoder for Igorplug-UDP to lirc
# Dr. Frank Borkenhagen
__version__ = "0.0.1"
__author__  = "Dr. Frank Borkenhagen"
__homepage__= "http://home.arcor.de/borkenhagen/IgorplugUDP"

def __doc__():
    print """
=================================================================
= Igorplug-UDP - transcodes IgorPlug-UDP packages into lircd    =
= UDP packages and sends to localhost:8765                      =
=================================================================
"""
    print "Version: ", __version__

from socket import *

host = "192.168.1.255"   #used network for Igorplug-UDP device
port = 6668              #listen to UDP port for Igorplug UDP
addr = (host,port)
buf = 64                 #max size of UDP package
UDPsignature=[0x23,0x37,0x39,0x8C] #the 1st four bytes in Igor's UDP data
on=1
off=0
debug=off
highlowtoggle=[chr(0x80),chr(0x00)]

#each UDP package will be parsed, validated, a 8 byte tuple will be returned
#each byte stands for one bit
def parseUDP(data):
    if not (data[0:4]==UDPsignature): return 0 #dump UDP package

    cnt=1                #locking coded data bit
    result=[]
    for i in data:
        if (cnt>4 and (not cnt%5)):
            if i==0x80: result.append(1)
            elif i==0x00: result.append(0)
            else: print "Unexpected Byte in one UDP package found",
        cnt+=1
    return result
        
if __name__ == '__main__':
    # Create socket and bind to address
    UDPSock = socket(AF_INET,SOCK_DGRAM)
    UDPSock.bind(addr)
    recording=0
    
    while 1:
        data=[]
        #read one UDP package
        dataraw,addr = UDPSock.recvfrom(buf)
        for i in  dataraw:
            data.append(ord(i))   #convert string to tuple of integers
        parsedUDP=parseUDP(data)  #parse each Igor's UDP package
      
        if debug: print "ATMEGA48 sent:", parsedUDP,

        #check sort of packages
        if not parsedUDP:
            if debug: print "UDP package dumped"
            continue
        elif parsedUDP.count(0x00)==8:  #UDP signature+40*0x00 -> start 
            if debug: print "Start",
            recording=on
            highlowtoggle=[chr(0x80),chr(0x00)] 
            send2lirc=""
            send2lirc += chr(0xFF)
            continue                    #goto read next UDP package
        elif parsedUDP.count(0x01)==8:  #UDP signature+40*0xFF -> stop 
            if debug: print "Stop",
            recording=off
            #one last space is required and one termination
            #Todo: check id 0x0F should be dynamic
            #send2lirc += chr(0x00)+chr(0x0F)+chr(0xFF)
            send2lirc += chr(0x00)+chr(0xFF)+chr(0xFF)
            if debug:
                print ; print
                for i in send2lirc:
                    print hex(ord(i)),
            LircUDP = socket(AF_INET, SOCK_DGRAM)
            LircUDP.sendto(send2lirc ,("127.0.0.1", 8765))
            LircUDP.close
            continue                    #goto read next UDP package
        if debug: print "Data ",
        if debug:
            if not recording: print "Header"
        if recording:
            if debug: print highlowtoggle,
            if debug: print parsedUDP
            cnt=Signallen=0

            for i in parsedUDP: 
                if i: Signallen += (2**cnt)
                cnt += 1
            #Todo: check why the theoretical value does not wor for all
            #Signallen=int(Signallen//1.13) #1.1921 #adjust timing
            Signallen=int(Signallen//1.1921) #adjust timing
            send2lirc += highlowtoggle[0]+chr(Signallen)
            highlowtoggle=highlowtoggle[::-1]
    UDPSock.close()
#EOF