from __future__ import print_function
import argparse
import unicodecsv as csv
import os
import pytsk3
import pyewf
import pyevt
import pyevtx
import sys
from utility.pytskutil import TSKUtil

"""
MIT License

Copyright (c) 2017 Chapin Bryce, Preston Miller

Please share comments and questions at:
    https://github.com/PythonForensics/PythonForensicsCookbook
    or email pyforcookbook@gmail.com

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
"""

__authors__ = ["Chapin Bryce", "Preston Miller"]
__date__ = 20170815
__description__ = "Script to handle event logs"


def main(evidence, image_type, log, win_event, fuzzy):
    # Create TSK object and query event log directory for Windows XP
    tsk_util = TSKUtil(evidence, image_type)
    event_dir = tsk_util.query_directory(win_event)
    if event_dir is not None:
        if fuzzy is True:
            event_log = tsk_util.recurse_files(log, path=win_event)
        else:
            event_log = tsk_util.recurse_files(
                log, path=win_event, logic="equal")
        if event_log is not None:
            event_data = []
            for hit in event_log:
                event_file = hit[2]
                temp_evt = write_file(event_file)
                if pyevt.check_file_signature(temp_evt):
                    evt_log = pyevt.open(temp_evt)
                    print("[+] Identified {} records in {}".format(
                        evt_log.number_of_records, temp_evt))
                    for i, record in enumerate(evt_log.records):
                        strings = ""
                        for s in record.strings:
                            if s is not None:
                                strings += s + "\n"

                        event_data.append([
                            i, hit[0], record.computer_name,
                            record.user_security_identifier,
                            record.creation_time, record.written_time,
                            record.event_category, record.source_name,
                            record.event_identifier, record.event_type,
                            strings, "",
                            os.path.join(win_event, hit[1].lstrip("//"))
                        ])

                elif pyevtx.check_file_signature(temp_evt):
                    evtx_log = pyevtx.open(temp_evt)
                    print("[+] Identified {} records in {}".format(
                          evtx_log.number_of_records, temp_evt))
                    for i, record in enumerate(evtx_log.records):
                        strings = ""
                        for s in record.strings:
                            if s is not None:
                                strings += s + "\n"

                        event_data.append([
                            i, hit[0], record.computer_name,
                            record.user_security_identifier, "",
                            record.written_time, record.event_level,
                            record.source_name, record.event_identifier,
                            "", strings, record.xml_string,
                            os.path.join(win_event, hit[1].lstrip("//"))
                        ])
                else:
                    print("[-] {} not a valid event log. Removing temp "
                          "file...".format(temp_evt))
                    os.remove(temp_evt)
                    continue
            write_output(event_data)
        else:
            print("[-] {} Event log not found in {} directory".format(
                log, win_event))
            sys.exit(3)

    else:
        print("[-] Win XP Event Log Directory {} not found".format(
            win_event))
        sys.exit(2)


def write_file(event_file):
    with open(event_file.info.name.name, "w") as outfile:
        outfile.write(event_file.read_random(0, event_file.info.meta.size))
    return event_file.info.name.name


def write_output(data):
    output_name = "parsed_event_logs.csv"
    print("[+] Writing {} to current working directory: {}".format(
          output_name, os.getcwd()))
    with open(output_name, "wb") as outfile:
        writer = csv.writer(outfile)

        writer.writerow([
            "Index", "File name", "Computer Name", "SID",
            "Event Create Date", "Event Written Date",
            "Event Category/Level", "Event Source", "Event ID",
            "Event Type", "Data", "XML Data", "File Path"
        ])

        writer.writerows(data)


if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        description=__description__,
        epilog="Developed by {} on {}".format(
            ", ".join(__authors__), __date__)
    )
    parser.add_argument("EVIDENCE_FILE", help="Evidence file path")
    parser.add_argument("TYPE", help="Type of Evidence",
                        choices=("raw", "ewf"))
    parser.add_argument("LOG_NAME",
                        help="Event Log Name (SecEvent.Evt, SysEvent.Evt, "
                             "etc.)")
    parser.add_argument("-d", help="Event log directory to scan",
                        default="/WINDOWS/SYSTEM32/WINEVT")
    parser.add_argument("-f", help="Enable fuzzy search for either evt or"
                        " evtx extension", action="store_true")
    args = parser.parse_args()

    if os.path.exists(args.EVIDENCE_FILE) and \
            os.path.isfile(args.EVIDENCE_FILE):
        main(args.EVIDENCE_FILE, args.TYPE, args.LOG_NAME, args.d, args.f)
    else:
        print("[-] Supplied input file {} does not exist or is not a "
              "file".format(args.EVIDENCE_FILE))
        sys.exit(1)