#!/usr/bin/python
import subprocess
import os
import re
import sys
import json



TINC_NETWORK =os.environ.get("TINC_NETWORK","retiolum")

# is_legacy is the parameter which defines if the tinc config files are handled old fashioned (parse from syslog), 
# or if the new and hip tincctl should be used
is_legacy=    os.environ.get("TINC_LEGACY",False)
SYSLOG_FILE = os.environ.get("LOG_FILE","/var/log/everything.log")


# Tags and Delimiters
TINC_TAG="tinc.%s" % TINC_NETWORK
BEGIN_NODES = "Nodes:"
END_NODES = "End of nodes."
BEGIN_SUBNET = "Subnet list:"
END_SUBNET = "End of subnet list"
BEGIN_EDGES = "Edges:"
END_EDGES = "End of edges."

def get_tinc_block(log_file):
  """ returns an iterateable block from the given log file (syslog) 
      This function became obsolete with the introduction of tincctl
  """
  from BackwardsReader import BackwardsReader
  tinc_block = []
  in_block = False
  bf = BackwardsReader(log_file)
  BOL = re.compile(".*tinc.%s\[[0-9]+\]: " % TINC_NETWORK)
  while True:
    line = bf.readline()
    if not line:
      raise Exception("end of file at log file? This should not happen!")
    line = BOL.sub('',line).strip()

    if END_SUBNET in line:
      in_block = True

    if not in_block:
      continue

    tinc_block.append(line)

    if BEGIN_NODES in line:
      break
  return reversed(tinc_block)

def parse_new_input():
  nodes = {} 
  pnodes = subprocess.Popen(["tincctl","-n",TINC_NETWORK,"dump","reachable","nodes"], stdout=subprocess.PIPE).communicate()[0]
  #pnodes = subprocess.check_output(["tincctl","-n",TINC_NETWORK,"dump","reachable","nodes"])
  for line in pnodes.split('\n'):
    if not line: continue
    l = line.split()
    nodes[l[0]]= { 'external-ip': l[2], 'external-port' : l[4] }
  psubnets = subprocess.check_output(["tincctl","-n",TINC_NETWORK,"dump","subnets"])
  for line in psubnets.split('\n'):
    if not line: continue
    l = line.split()
    try:
      if not nodes[l[2]].get('internal-ip',False):
         nodes[l[2]]['internal-ip'] = []
      nodes[l[2]]['internal-ip'].append(l[0].split('#')[0])
    except KeyError:
      pass # node does not exist (presumably)
  pedges = subprocess.check_output(["tincctl","-n",TINC_NETWORK,"dump","edges"])
  for line in pedges.split('\n'):
    if not line: continue
    l = line.split()
    try:
      if not nodes[l[0]].has_key('to') :
        nodes[l[0]]['to'] = []
      nodes[l[0]]['to'].append(
          {'name':l[2],'addr':l[4],'port':l[6],'weight' : l[10] })
    except KeyError:
      pass #node does not exist
  return nodes

def parse_input(log_data):
  nodes={}
  for line in log_data:
    if BEGIN_NODES in line :
      nodes={}
      for line in log_data:
        if END_NODES in line :
          break
        l = line.replace('\n','').split() #TODO unhack me
        nodes[l[0]]= { 'external-ip': l[2], 'external-port' : l[4] }
    if BEGIN_SUBNET in line :
      for line in log_data:
        if END_SUBNET in line :
          break
        l = line.replace('\n','').split() 
        if not nodes[l[2]].get('internal-ip',False):
           nodes[l[2]]['internal-ip'] = []
        nodes[l[2]]['internal-ip'].append(l[0].split('#')[0])
    if BEGIN_EDGES in line :
      edges = {}
      for line in log_data:
        if END_EDGES in line :
          break
        l = line.replace('\n','').split() 
        if not nodes[l[0]].has_key('to') :
          nodes[l[0]]['to'] = []
        nodes[l[0]]['to'].append(
            {'name':l[2],'addr':l[4],'port':l[6],'weight' : l[10] })
  return nodes


if __name__ == '__main__':
  import subprocess,time
  if is_legacy:
    subprocess.call(["pkill","-SIGUSR2", "tincd"])
    time.sleep(1)
    print json.dumps(parse_input((get_tinc_block(SYSLOG_FILE))))
  else:
    print json.dumps(parse_new_input())