"""
olefile (formerly OleFileIO_PL)

Module to read/write Microsoft OLE2 files (also called Structured Storage or
Microsoft Compound Document File Format), such as Microsoft Office 97-2003
documents, Image Composer and FlashPix files, Outlook messages, ...
This version is compatible with Python 2.7 and 3.4+

Project website: https://www.decalage.info/olefile

olefile is copyright (c) 2005-2018 Philippe Lagadec
(https://www.decalage.info)

olefile is based on the OleFileIO module from the PIL library v1.1.7
See: http://www.pythonware.com/products/pil/index.htm
and http://svn.effbot.org/public/tags/pil-1.1.7/PIL/OleFileIO.py

The Python Imaging Library (PIL) is
Copyright (c) 1997-2009 by Secret Labs AB
Copyright (c) 1995-2009 by Fredrik Lundh

See source code and LICENSE.txt for information on usage and redistribution.
"""

# Since OleFileIO_PL v0.45, only Python 2.7 and 3.4+ are supported
# This import enables print() as a function rather than a keyword
# (main requirement to be compatible with Python 3.x)
# The comment on the line below should be printed on Python 2.5 or older:
from __future__ import print_function   # This version of olefile requires Python 2.7 or 3.4+.


#--- LICENSE ------------------------------------------------------------------

# olefile (formerly OleFileIO_PL) is copyright (c) 2005-2018 Philippe Lagadec
# (https://www.decalage.info)
#
# 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.
#
# 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.

# ----------
# PIL License:
#
# olefile is based on source code from the OleFileIO module of the Python
# Imaging Library (PIL) published by Fredrik Lundh under the following license:

# The Python Imaging Library (PIL) is
#    Copyright (c) 1997-2009 by Secret Labs AB
#    Copyright (c) 1995-2009 by Fredrik Lundh
#
# By obtaining, using, and/or copying this software and/or its associated
# documentation, you agree that you have read, understood, and will comply with
# the following terms and conditions:
#
# Permission to use, copy, modify, and distribute this software and its
# associated documentation for any purpose and without fee is hereby granted,
# provided that the above copyright notice appears in all copies, and that both
# that copyright notice and this permission notice appear in supporting
# documentation, and that the name of Secret Labs AB or the author(s) not be used
# in advertising or publicity pertaining to distribution of the software
# without specific, written prior permission.
#
# SECRET LABS AB AND THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
# SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
# IN NO EVENT SHALL SECRET LABS AB OR THE AUTHORS BE LIABLE FOR ANY SPECIAL,
# INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
# OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
# PERFORMANCE OF THIS SOFTWARE.

__date__    = "2018-09-09"
__version__ = '0.46'
__author__  = "Philippe Lagadec"

__all__ = ['isOleFile', 'OleFileIO', 'OleMetadata', 'enable_logging',
           'MAGIC', 'STGTY_EMPTY', 'KEEP_UNICODE_NAMES',
           'STGTY_STREAM', 'STGTY_STORAGE', 'STGTY_ROOT', 'STGTY_PROPERTY',
           'STGTY_LOCKBYTES', 'MINIMAL_OLEFILE_SIZE',
           'DEFECT_UNSURE', 'DEFECT_POTENTIAL', 'DEFECT_INCORRECT',
           'DEFECT_FATAL', 'DEFAULT_PATH_ENCODING',
           'MAXREGSECT', 'DIFSECT', 'FATSECT', 'ENDOFCHAIN', 'FREESECT',
           'MAXREGSID', 'NOSTREAM', 'UNKNOWN_SIZE', 'WORD_CLSID'
]

import io
import sys
import struct, array, os.path, datetime, logging

#=== COMPATIBILITY WORKAROUNDS ================================================

# For Python 3.x, need to redefine long as int:
if str is not bytes:
    long = int

# Need to make sure we use xrange both on Python 2 and 3.x:
try:
    # on Python 2 we need xrange:
    iterrange = xrange
except:
    # no xrange, for Python 3 it was renamed as range:
    iterrange = range

#[PL] workaround to fix an issue with array item size on 64 bits systems:
if array.array('L').itemsize == 4:
    # on 32 bits platforms, long integers in an array are 32 bits:
    UINT32 = 'L'
elif array.array('I').itemsize == 4:
    # on 64 bits platforms, integers in an array are 32 bits:
    UINT32 = 'I'
elif array.array('i').itemsize == 4:
    # On 64 bit Jython, signed integers ('i') are the only way to store our 32
    # bit values in an array in a *somewhat* reasonable way, as the otherwise
    # perfectly suited 'H' (unsigned int, 32 bits) results in a completely
    # unusable behaviour. This is most likely caused by the fact that Java
    # doesn't have unsigned values, and thus Jython's "array" implementation,
    # which is based on "jarray", doesn't have them either.
    # NOTE: to trick Jython into converting the values it would normally
    # interpret as "signed" into "unsigned", a binary-and operation with
    # 0xFFFFFFFF can be used. This way it is possible to use the same comparing
    # operations on all platforms / implementations. The corresponding code
    # lines are flagged with a 'JYTHON-WORKAROUND' tag below.
    UINT32 = 'i'
else:
    raise ValueError('Need to fix a bug with 32 bit arrays, please contact author...')


#[PL] These workarounds were inspired from the Path module
# (see http://www.jorendorff.com/articles/python/path/)
try:
    basestring
except NameError:
    basestring = str

#[PL] Experimental setting: if True, OLE filenames will be kept in Unicode
# if False (default PIL behaviour), all filenames are converted to Latin-1.
KEEP_UNICODE_NAMES = True

if sys.version_info[0] < 3:
    # On Python 2.x, the default encoding for path names is UTF-8:
    DEFAULT_PATH_ENCODING = 'utf-8'
else:
    # On Python 3.x, the default encoding for path names is Unicode (None):
    DEFAULT_PATH_ENCODING = None


# === LOGGING =================================================================

def get_logger(name, level=logging.CRITICAL+1):
    """
    Create a suitable logger object for this module.
    The goal is not to change settings of the root logger, to avoid getting
    other modules' logs on the screen.
    If a logger exists with same name, reuse it. (Else it would have duplicate
    handlers and messages would be doubled.)
    The level is set to CRITICAL+1 by default, to avoid any logging.
    """
    # First, test if there is already a logger with the same name, else it
    # will generate duplicate messages (due to duplicate handlers):
    if name in logging.Logger.manager.loggerDict:
        #NOTE: another less intrusive but more "hackish" solution would be to
        # use getLogger then test if its effective level is not default.
        logger = logging.getLogger(name)
        # make sure level is OK:
        logger.setLevel(level)
        return logger
    # get a new logger:
    logger = logging.getLogger(name)
    # only add a NullHandler for this logger, it is up to the application
    # to configure its own logging:
    logger.addHandler(logging.NullHandler())
    logger.setLevel(level)
    return logger


# a global logger object used for debugging:
log = get_logger('olefile')


def enable_logging():
    """
    Enable logging for this module (disabled by default).
    This will set the module-specific logger level to NOTSET, which
    means the main application controls the actual logging level.
    """
    log.setLevel(logging.NOTSET)


#=== CONSTANTS ===============================================================

#: magic bytes that should be at the beginning of every OLE file:
MAGIC = b'\xD0\xCF\x11\xE0\xA1\xB1\x1A\xE1'

#[PL]: added constants for Sector IDs (from AAF specifications)
MAXREGSECT = 0xFFFFFFFA #: (-6) maximum SECT
DIFSECT    = 0xFFFFFFFC #: (-4) denotes a DIFAT sector in a FAT
FATSECT    = 0xFFFFFFFD #: (-3) denotes a FAT sector in a FAT
ENDOFCHAIN = 0xFFFFFFFE #: (-2) end of a virtual stream chain
FREESECT   = 0xFFFFFFFF #: (-1) unallocated sector

#[PL]: added constants for Directory Entry IDs (from AAF specifications)
MAXREGSID  = 0xFFFFFFFA #: (-6) maximum directory entry ID
NOSTREAM   = 0xFFFFFFFF #: (-1) unallocated directory entry

#[PL] object types in storage (from AAF specifications)
STGTY_EMPTY     = 0 #: empty directory entry
STGTY_STORAGE   = 1 #: element is a storage object
STGTY_STREAM    = 2 #: element is a stream object
STGTY_LOCKBYTES = 3 #: element is an ILockBytes object
STGTY_PROPERTY  = 4 #: element is an IPropertyStorage object
STGTY_ROOT      = 5 #: element is a root storage

# Unknown size for a stream (used by OleStream):
UNKNOWN_SIZE = 0x7FFFFFFF

#
# --------------------------------------------------------------------
# property types

VT_EMPTY=0; VT_NULL=1; VT_I2=2; VT_I4=3; VT_R4=4; VT_R8=5; VT_CY=6;
VT_DATE=7; VT_BSTR=8; VT_DISPATCH=9; VT_ERROR=10; VT_BOOL=11;
VT_VARIANT=12; VT_UNKNOWN=13; VT_DECIMAL=14; VT_I1=16; VT_UI1=17;
VT_UI2=18; VT_UI4=19; VT_I8=20; VT_UI8=21; VT_INT=22; VT_UINT=23;
VT_VOID=24; VT_HRESULT=25; VT_PTR=26; VT_SAFEARRAY=27; VT_CARRAY=28;
VT_USERDEFINED=29; VT_LPSTR=30; VT_LPWSTR=31; VT_FILETIME=64;
VT_BLOB=65; VT_STREAM=66; VT_STORAGE=67; VT_STREAMED_OBJECT=68;
VT_STORED_OBJECT=69; VT_BLOB_OBJECT=70; VT_CF=71; VT_CLSID=72;
VT_VECTOR=0x1000;

# map property id to name (for debugging purposes)
# VT = {}
# for keyword, var in list(vars().items()):
#     if keyword[:3] == "VT_":
#         VT[var] = keyword

#
# --------------------------------------------------------------------
# Some common document types (root.clsid fields)

WORD_CLSID = "00020900-0000-0000-C000-000000000046"
#TODO: check Excel, PPT, ...

#[PL]: Defect levels to classify parsing errors - see OleFileIO._raise_defect()
DEFECT_UNSURE =    10    # a case which looks weird, but not sure it's a defect
DEFECT_POTENTIAL = 20    # a potential defect
DEFECT_INCORRECT = 30    # an error according to specifications, but parsing
                         # can go on
DEFECT_FATAL =     40    # an error which cannot be ignored, parsing is
                         # impossible

# Minimal size of an empty OLE file, with 512-bytes sectors = 1536 bytes
# (this is used in isOleFile and OleFile.open)
MINIMAL_OLEFILE_SIZE = 1536


#=== FUNCTIONS ===============================================================

def isOleFile (filename):
    """
    Test if a file is an OLE container (according to the magic bytes in its header).

    .. note::
        This function only checks the first 8 bytes of the file, not the
        rest of the OLE structure.

    .. versionadded:: 0.16

    :param filename: filename, contents or file-like object of the OLE file (string-like or file-like object)

        - if filename is a string smaller than 1536 bytes, it is the path
          of the file to open. (bytes or unicode string)
        - if filename is a string longer than 1535 bytes, it is parsed
          as the content of an OLE file in memory. (bytes type only)
        - if filename is a file-like object (with read and seek methods),
          it is parsed as-is.

    :type filename: bytes or str or unicode or file
    :returns: True if OLE, False otherwise.
    :rtype: bool
    """
    # check if filename is a string-like or file-like object:
    if hasattr(filename, 'read'):
        # file-like object: use it directly
        header = filename.read(len(MAGIC))
        # just in case, seek back to start of file:
        filename.seek(0)
    elif isinstance(filename, bytes) and len(filename) >= MINIMAL_OLEFILE_SIZE:
        # filename is a bytes string containing the OLE file to be parsed:
        header = filename[:len(MAGIC)]
    else:
        # string-like object: filename of file on disk
        with open(filename, 'rb') as fp:
            header = fp.read(len(MAGIC))
    if header == MAGIC:
        return True
    else:
        return False


if bytes is str:
    # version for Python 2.x
    def i8(c):
        return ord(c)
else:
    # version for Python 3.x
    def i8(c):
        return c if c.__class__ is int else c[0]


def i16(c, o = 0):
    """
    Converts a 2-bytes (16 bits) string to an integer.

    :param c: string containing bytes to convert
    :param o: offset of bytes to convert in string
    """
    return struct.unpack("<H", c[o:o+2])[0]


def i32(c, o = 0):
    """
    Converts a 4-bytes (32 bits) string to an integer.

    :param c: string containing bytes to convert
    :param o: offset of bytes to convert in string
    """
    return struct.unpack("<I", c[o:o+4])[0]