#!/usr/bin/python2

"""
Transform a logfile from glideinWMS - or stdin - to
the corresponding HTCondor file
"""

import os
import re
import sys
import gzip
import binascii
import optparse
import StringIO

# The following functions
# - get_Compressed_raw
# - get_Compressed
# - get_CondorLog
# Are taken from the glideinWMS source code; in particular,
# this library:
#
# https://github.com/holzman/glideinWMS/blob/master/factory/tools/lib/gWftLogParser.py
#
# If you need to take this code, I recommend using the above version as
# the one below may be out-of-date.
#
# This copying is a convenience until proper packaging is done.
# These functions come with the following copyright notice and
# license:

# Copyright (c) 2009, FERMI NATIONAL ACCELERATOR LABORATORY 
# All rights reserved.
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
#     * Redistributions of source code must retain the above copyright
#       notice, this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above
#       copyright notice, this list of conditions and the following
#       disclaimer in the documentation and/or other materials provided
#       with the distribution.
#     * Neither the name of the FERMI NATIONAL ACCELERATOR LABORATORY,
#       nor the names of its contributors may be used to endorse or
#       promote products derived from this software without specific
#       prior written permission.

# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 


# extract the blob from a glidein log file starting from position 
def get_Compressed_raw(log_fp, start_str, start_pos=0):
    SL_START_RE=re.compile("%s\nbegin-base64 644 -\n"%start_str,re.M|re.DOTALL)

    # first find the header that delimits the log in the file
    result_buf = ''
    found_start = False
    prev_line = ''
    prev_line2 = ''
    for line in log_fp.xreadlines():
        if found_start:
           if line.startswith("===="):
               break
           result_buf += line
           continue

        start_re=SL_START_RE.search(prev_line2 + prev_line + line, 0)
        if not start_re:
            prev_line2 = prev_line
            prev_line = line
            continue
        found_start = True

    return result_buf


# extract the blob from a glidein log file
def get_Compressed(log_fp, start_str):
    raw_data=get_Compressed_raw(log_fp, start_str)
    if raw_data:
        gzip_data=binascii.a2b_base64(raw_data)
        del raw_data
        data_fd=gzip.GzipFile(fileobj=StringIO.StringIO(gzip_data))
        data=data_fd.read()
    else:
        data=raw_data
    return data


# extract the Condor Log from a glidein log file
# condor_log_id should be something like "StartdLog"
def get_CondorLog(log_fp, condor_log_id):
    start_str="^%s\n======== gzip . uuencode ============="%condor_log_id
    return get_Compressed(log_fp, start_str)

def get_Summary(log_fp):
    start_str="=== Encoded XML description of glidein activity ==="
    return get_Compressed(log_fp, start_str)

#
# Below is code *not* from glideinWMS project and covered by the Kestrel copyright.
#

def get_opt():
    usage = "usage: %prog [-c CondorLog] fname"
    parser = optparse.OptionParser(usage=usage)
    parser.add_option("-c", "--condor-log", dest="condor", help="HTCondor log file to decompress (MasterLog/StartdLog/StarterLog/StartdHistoryLog)", default="StartdLog")
    parser.add_option("-s", "--summary", dest="summary", help="Print activity summary", default=False, action="store_true")

    opts, args = parser.parse_args()

    if len(args) != 1:
        parser.error("Incorrect number of arguments; must specify a single filename or '-' to denote stdin")

    if args[0] == '-':
       fp = sys.stdin
    else:
       fp = open(args[0], "r")

    return opts, fp

def main():
    opts, fp = get_opt()

    if opts.summary:
        print get_Summary(fp)
    else:
        print get_CondorLog(fp, opts.condor),

if __name__ == "__main__":
    main()