#! /usr/bin/env python

""" Extract SIP messages from a file and store them in a file named by its call-id """

# import the module needed for regular expressions
import re

# regexp to match sip messages
sipmessage = re.compile(r'BYE|INVITE|SIP|ACK|CANCEL|OPTIONS|MESSAGE|PRACK|REFER|INFO|SUBSCRIBE|NOTIFY')
# regexp to match Call-ID
sipcallid = re.compile(r'Call-ID')

# dictionnary that'll hold the call-id named files
dictfiles = {}

filetraces = open('traces.txt', 'r')                    # open the file containing the traces in read mode

templine = filetraces.readline()                        # iterate through the file until the end of the file
while templine:
    if sipmessage.match(templine):                      # there is a sip message on this line
        callid_line = filetraces.readline()             # find its call id
        while not sipcallid.match(callid_line):
            callid_line = filetraces.readline()
        filename = callid_line[9:-1]                    # take out the "call-id : " at the beginning and the "\n" at the end
        if not filename in dictfiles:                   # is this file already created
            dictfiles[filename] = open(filename, 'a')   # if not, open the file in append mode
        dictfiles[filename].write(templine)             # append the sip message
    templine = filetraces.readline()
filetraces.close()

for filename in dictfiles:                              # close all the files that have been opened
    dictfiles[filename].close()