# -*- coding:utf8 -*-
import asynchat
import asyncore
import socket
import sys
import json
# Master-Master
# 1 quell
# 1 ziel
# 1 1primaerbefehl
# 1 sekundaerbefehl
# 1 n=laenge (bytes)
# n daten....
# 1 CRC
# 1 ack (=0x00 || 0xff)
# 1 syn (=0xaa)

# Master-Slave
# 1 quell
# 1 ziel
# 1 1primaerbefehl
# 1 sekundaerbefehl
# 1 n=laenge (bytes)
# n daten vom master/Anfrage....
# 1 CRC
# 1 ack (=0x00 || 0xff)
# 1 m=länge (bytes)
# m daten vom slave/Antwort...
# 1 syn (=0xaa)
deviceDescription = [
    {'address':0x03, 'type':'master', 'description':'Feuerungsautomat'},
    {'address':0x10, 'type':'master', 'description':'Heizungsregler #2'},
    {'address':0x30, 'type':'master', 'description':'Heizkreisregler 1'},
    {'address':0x70, 'type':'master', 'description':'Heizkreisregler 2'},
    {'address':0x71, 'type':'master', 'description':'Heizungsregler #9'},
    {'address':0xf1, 'type':'master', 'description':'Heizungsregler #10'},
    {'address':0x50, 'type':'slave', 'description':'Mischer 1'},
    {'address':0x51, 'type':'slave', 'description':'Mischer 2'},
    {'address':0xfe, 'type':'broadcast', 'description':'Broadcast'},
]

packetDescription = [
     {'primary':0x7,  'secondary':0x9, 'name':'UNKNOWN'},
     {'primary':0x14, 'secondary':0x7, 'name':'UNKNOWN'},
     #  Response
     #p[0] = Einheit (1=>Liter, 2=>Kubik)
     #p[1] = 10^0
     #p[2] = 10^2
     #p[3] = 10^4
     #p[4] = 10^6
     {'primary':0x3,  'secondary':0x8, 'name':'Gesamtbrennstoffmengenzähle lesen'},
     {'primary':''},
]

def formatHex(data):
    return " ".join(map(lambda byte: "%.2x"%ord(byte), data))

def getDsc(address):
    dev=filter(lambda dev: dev['address'] == address, deviceDescription)
    if len(dev)>0:
        return dev[0]['description']
    else:
        return None

class EbusPacket(object):
    def __init__(self, source, destination, primary_command, secondary_command):
        self.source = source
        self.destination = destination
        self.primary_command = primary_command
        self.secondary_command = secondary_command

    def name(self):
        desc = filter(lambda p: p['primary'] == self.primary_command \
            and p['secondary'] == self.secondary_command, packetDescription)
        if len(desc) > 0:
            return desc[0]['name']
        else:
            return "UNKNOWN"

    def __str__(self):
        return "<%-18s name=\"%-15s\" source=\"%s\" destination=\"%s\" primary=0x%x secondary=0x%x>" % \
            (self.__class__.__name__, self.name(), getDsc(self.source), getDsc(self.destination), \
             self.primary_command, self.secondary_command)

class EbusMasterMaster(EbusPacket):
    def __init__(self, source, destination, primary_command, secondary_command, data):
        EbusPacket.__init__(self, source, destination, primary_command, secondary_command)
        self.data = data


class EbusMasterSlave(EbusPacket):
    def __init__(self, source, destination, primary_command, secondary_command, request, response):
        EbusPacket.__init__(self, source, destination, primary_command, secondary_command)
        self.request = request
        self.response = response

class EbusBroadcast(EbusPacket):
     def __init__(self, source, destination, primary_command, secondary_command, data):
        EbusPacket.__init__(self, source, destination, primary_command, secondary_command)
        self.data = data

   

class Fetcher(asynchat.async_chat):
    def __init__(self):
        self.buffer = ""

        asynchat.async_chat.__init__(self)
        self.set_terminator("")
        self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
        self.connect(("10.2.2.200", 7970))

        self.packetIndex = 0
        self.buf = ""

    def collect_incoming_data(self,data):
        for it in range(len(data)):
            if data[it] == "\xaa":
                if it+1 < len(data) and data[it+1] != "\xaa":
                    self._parse(self.buf)
                    self.buf = ""
                    self.packetIndex = 0
            else:
                self.buf += data[it]
                self.packetIndex = self.packetIndex + 1
                #print "%.2x [%d]" % (ord(data[it]),self.packetIndex)

    def _parse(self,data):
        if len(data) < 2:
            print "GAGA"
            return
        source = ord(data[0])
        destination = ord(data[1])

        sourceDevice = filter(lambda dev: dev['address'] == source, deviceDescription)
        destinationDevice = filter(lambda dev: dev['address'] == destination, deviceDescription)
        if len(sourceDevice) == 0 or len(destinationDevice) == 0:
            print "Unbekanntes Paket: source=%x destination=%x" % (source, destination)
            return

        if len(data) < 9:
            print "Unvollständige Daten"
            return

        primaryCommand = ord(data[3])
        secondaryCommand = ord(data[4])
        payloadLength = ord(data[5])
        payload = data[6:6+payloadLength]
        p = None
        if sourceDevice[0]['type'] == 'master' and destinationDevice[0]['type'] == 'master':
            p = EbusMasterMaster(source, destination, primaryCommand, secondaryCommand, payload)
            print p
            print "payload=%s" % formatHex(payload)
        elif sourceDevice[0]['type'] == 'master' and destinationDevice[0]['type'] == 'slave':
            p = EbusMasterSlave(source, destination, primaryCommand, secondaryCommand, None, None)
            print p
        elif sourceDevice[0]['type'] == 'master' and destinationDevice[0]['type'] == 'broadcast':
            p = EbusBroadcast(source, destination, primaryCommand, secondaryCommand, payload)
            print p
            print "payload=%s" % formatHex(payload)
        else:
            print "KOMISCHES ZEUG"
            return

Fetcher()
asyncore.loop()