###     ###
# Imports #
###     ###

import datetime, os, plistlib, struct, sys, itertools
from io import BytesIO

if sys.version_info < (3,0):
    # Force use of StringIO instead of cStringIO as the latter
    # has issues with Unicode strings
    from StringIO import StringIO

try:
    FMT_XML = plistlib.FMT_XML
    FMT_BINARY = plistlib.FMT_BINARY
except:
    FMT_XML = "FMT_XML"
    FMT_BINARY = "FMT_BINARY"

###            ###
# Helper Methods #
###            ###

def _check_py3():
    return True if sys.version_info >= (3, 0) else False

def _is_binary(fp):
    if isinstance(fp, _get_inst()):
        return fp.startswith(b"bplist00")
    header = fp.read(32)
    fp.seek(0)
    return header[:8] == b'bplist00'

def _get_inst():
    if _check_py3():
        return (str)
    else:
        return (str, unicode)

###                             ###
# Deprecated Functions - Remapped #
###                             ###

def readPlist(pathOrFile):
    if not isinstance(pathOrFile, _get_inst()):
        return load(pathOrFile)
    with open(pathOrFile, "rb") as f:
        return load(f)

def writePlist(value, pathOrFile):
    if not isinstance(pathOrFile, _get_inst()):
        return dump(value, pathOrFile, fmt=FMT_XML, sort_keys=True, skipkeys=False)
    with open(pathOrFile, "wb") as f:
        return dump(value, f, fmt=FMT_XML, sort_keys=True, skipkeys=False)

###                ###
# Remapped Functions #
###                ###

def load(fp, fmt=None, use_builtin_types=None, dict_type=dict):
    if _check_py3():
        use_builtin_types = True if use_builtin_types == None else use_builtin_types
        # We need to monkey patch this to allow for hex integers - code taken/modified from 
        # https://github.com/python/cpython/blob/3.8/Lib/plistlib.py
        if fmt is None:
            header = fp.read(32)
            fp.seek(0)
            for info in plistlib._FORMATS.values():
                if info['detect'](header):
                    P = info['parser']
                    break
            else:
                raise plistlib.InvalidFileException()
        else:
            P = plistlib._FORMATS[fmt]['parser']
        p = P(use_builtin_types=use_builtin_types, dict_type=dict_type)
        if isinstance(p,plistlib._PlistParser):
            # Monkey patch!
            def end_integer():
                d = p.get_data()
                p.add_object(int(d,16) if d.lower().startswith("0x") else int(d))
            p.end_integer = end_integer
        return p.parse(fp)
    elif not _is_binary(fp):
        # Is not binary - assume a string - and try to load
        # We avoid using readPlistFromString() as that uses
        # cStringIO and fails when Unicode strings are detected
        # Don't subclass - keep the parser local
        from xml.parsers.expat import ParserCreate
        # Create a new PlistParser object - then we need to set up
        # the values and parse.
        p = plistlib.PlistParser()
        # We also need to monkey patch this to allow for other dict_types
        def begin_dict(attrs):
            d = dict_type()
            p.addObject(d)
            p.stack.append(d)
        def end_integer():
            d = p.getData()
            p.addObject(int(d,16) if d.lower().startswith("0x") else int(d))
        p.begin_dict = begin_dict
        p.end_integer = end_integer
        parser = ParserCreate()
        parser.StartElementHandler = p.handleBeginElement
        parser.EndElementHandler = p.handleEndElement
        parser.CharacterDataHandler = p.handleData
        if isinstance(fp, unicode):
            # Encode unicode -> string; use utf-8 for safety
            fp = fp.encode("utf-8")
        if isinstance(fp,_get_inst()):
            # It's a string - let's wrap it up
            fp = StringIO(fp)
        # Parse it
        parser.ParseFile(fp)
        return p.root
    else:
        use_builtin_types = False if use_builtin_types == None else use_builtin_types
        p = _BinaryPlistParser(use_builtin_types=use_builtin_types, dict_type=dict_type)
        return p.parse(fp)

def loads(value, fmt=None, use_builtin_types=None, dict_type=dict):
    if _check_py3() and isinstance(value, _get_inst()):
        # If it's a string - encode it
        value = value.encode()
    return load(BytesIO(value),fmt=fmt,use_builtin_types=use_builtin_types,dict_type=dict_type)

def dump(value, fp, fmt=FMT_XML, sort_keys=True, skipkeys=False):
    if _check_py3():
        plistlib.dump(value, fp, fmt=fmt, sort_keys=sort_keys, skipkeys=skipkeys)
    else:
        if fmt == FMT_XML:
            # We need to monkey patch a bunch here too in order to avoid auto-sorting
            # of keys
            writer = plistlib.PlistWriter(fp)
            def writeDict(d):
                if d:
                    writer.beginElement("dict")
                    items = sorted(d.items()) if sort_keys else d.items()
                    for key, value in items:
                        if not isinstance(key, (str,unicode)):
                            if skipkeys:
                                continue
                            raise TypeError("keys must be strings")
                        writer.simpleElement("key", key)
                        writer.writeValue(value)
                    writer.endElement("dict")
                else:
                    writer.simpleElement("dict")
            writer.writeDict = writeDict
            writer.writeln("<plist version=\"1.0\">")
            writer.writeValue(value)
            writer.writeln("</plist>")
        elif fmt == FMT_BINARY:
            # Assume binary at this point
            writer = _BinaryPlistWriter(fp, sort_keys=sort_keys, skipkeys=skipkeys)
            writer.write(value)
        else:
            # Not a proper format
            raise ValueError("Unsupported format: {}".format(fmt))
    
def dumps(value, fmt=FMT_XML, skipkeys=False, sort_keys=True):
    if _check_py3():
        return plistlib.dumps(value, fmt=fmt, skipkeys=skipkeys, sort_keys=sort_keys).decode("utf-8")
    else:
        # We avoid using writePlistToString() as that uses
        # cStringIO and fails when Unicode strings are detected
        f = StringIO()
        dump(value, f, fmt=fmt, skipkeys=skipkeys, sort_keys=sort_keys)
        return f.getvalue()

###                        ###
# Binary Plist Stuff For Py2 #
###                        ###

# From the python 3 plistlib.py source:  https://github.com/python/cpython/blob/3.7/Lib/plistlib.py
# Tweaked to function on Python 2

class InvalidFileException (ValueError):
    def __init__(self, message="Invalid file"):
        ValueError.__init__(self, message)

_BINARY_FORMAT = {1: 'B', 2: 'H', 4: 'L', 8: 'Q'}

_undefined = object()

class _BinaryPlistParser:
    """
    Read or write a binary plist file, following the description of the binary
    format.  Raise InvalidFileException in case of error, otherwise return the
    root object.
    see also: http://opensource.apple.com/source/CF/CF-744.18/CFBinaryPList.c
    """
    def __init__(self, use_builtin_types, dict_type):
        self._use_builtin_types = use_builtin_types
        self._dict_type = dict_type

    def parse(self, fp):
        try:
            # The basic file format:
            # HEADER
            # object...
            # refid->offset...
            # TRAILER
            self._fp = fp
            self._fp.seek(-32, os.SEEK_END)
            trailer = self._fp.read(32)
            if len(trailer) != 32:
                raise InvalidFileException()
            (
                offset_size, self._ref_size, num_objects, top_object,
                offset_table_offset
            ) = struct.unpack('>6xBBQQQ', trailer)
            self._fp.seek(offset_table_offset)
            self._object_offsets = self._read_ints(num_objects, offset_size)
            self._objects = [_undefined] * num_objects
            return self._read_object(top_object)

        except (OSError, IndexError, struct.error, OverflowError,
                UnicodeDecodeError):
            raise InvalidFileException()

    def _get_size(self, tokenL):
        """ return the size of the next object."""
        if tokenL == 0xF:
            m = ord(self._fp.read(1)[0]) & 0x3
            s = 1 << m
            f = '>' + _BINARY_FORMAT[s]
            return struct.unpack(f, self._fp.read(s))[0]

        return tokenL

    def _read_ints(self, n, size):
        data = self._fp.read(size * n)
        if size in _BINARY_FORMAT:
            return struct.unpack('>' + _BINARY_FORMAT[size] * n, data)
        else:
            if not size or len(data) != size * n:
                raise InvalidFileException()
            return tuple(int.from_bytes(data[i: i + size], 'big')
                         for i in range(0, size * n, size))

    def _read_refs(self, n):
        return self._read_ints(n, self._ref_size)

    def _read_object(self, ref):
        """
        read the object by reference.
        May recursively read sub-objects (content of an array/dict/set)
        """
        result = self._objects[ref]
        if result is not _undefined:
            return result

        offset = self._object_offsets[ref]
        self._fp.seek(offset)
        token = ord(self._fp.read(1)[0])
        tokenH, tokenL = token & 0xF0, token & 0x0F

        if token == 0: # \x00 or 0x00
            result = None

        elif token == 8: # \x08 or 0x08
            result = False

        elif token == 9: # \x09 or 0x09
            result = True

        # The referenced source code also mentions URL (0x0c, 0x0d) and
        # UUID (0x0e), but neither can be generated using the Cocoa libraries.

        elif token == 15: # \x0f or 0x0f
            result = b''

        elif tokenH == 0x10:  # int
            result = 0
            for k in xrange((2 << tokenL) - 1):
                result = (result << 8) + ord(self._fp.read(1))
            # result = int.from_bytes(self._fp.read(1 << tokenL),
            #                        'big', signed=tokenL >= 3)

        elif token == 0x22: # real
            result = struct.unpack('>f', self._fp.read(4))[0]

        elif token == 0x23: # real
            result = struct.unpack('>d', self._fp.read(8))[0]

        elif token == 0x33:  # date
            f = struct.unpack('>d', self._fp.read(8))[0]
            # timestamp 0 of binary plists corresponds to 1/1/2001
            # (year of Mac OS X 10.0), instead of 1/1/1970.
            result = (datetime.datetime(2001, 1, 1) +
                      datetime.timedelta(seconds=f))

        elif tokenH == 0x40:  # data
            s = self._get_size(tokenL)
            if self._use_builtin_types:
                result = self._fp.read(s)
            else:
                result = plistlib.Data(self._fp.read(s))

        elif tokenH == 0x50:  # ascii string
            s = self._get_size(tokenL)
            result =  self._fp.read(s).decode('ascii')
            result = result

        elif tokenH == 0x60:  # unicode string
            s = self._get_size(tokenL)
            result = self._fp.read(s * 2).decode('utf-16be')

        # tokenH == 0x80 is documented as 'UID' and appears to be used for
        # keyed-archiving, not in plists.

        elif tokenH == 0xA0:  # array
            s = self._get_size(tokenL)
            obj_refs = self._read_refs(s)
            result = []
            self._objects[ref] = result
            result.extend(self._read_object(x) for x in obj_refs)

        # tokenH == 0xB0 is documented as 'ordset', but is not actually
        # implemented in the Apple reference code.

        # tokenH == 0xC0 is documented as 'set', but sets cannot be used in
        # plists.

        elif tokenH == 0xD0:  # dict
            s = self._get_size(tokenL)
            key_refs = self._read_refs(s)
            obj_refs = self._read_refs(s)
            result = self._dict_type()
            self._objects[ref] = result
            for k, o in zip(key_refs, obj_refs):
                key = self._read_object(k)
                if isinstance(key, plistlib.Data):
                    key = key.data
                result[key] = self._read_object(o)

        else:
            raise InvalidFileException()

        self._objects[ref] = result
        return result

def _count_to_size(count):
    if count < 1 << 8:
        return 1

    elif count < 1 << 16:
        return 2

    elif count << 1 << 32:
        return 4

    else:
        return 8

_scalars = (str, int, float, datetime.datetime, bytes)

class _BinaryPlistWriter (object):
    def __init__(self, fp, sort_keys, skipkeys):
        self._fp = fp
        self._sort_keys = sort_keys
        self._skipkeys = skipkeys

    def write(self, value):

        # Flattened object list:
        self._objlist = []

        # Mappings from object->objectid
        # First dict has (type(object), object) as the key,
        # second dict is used when object is not hashable and
        # has id(object) as the key.
        self._objtable = {}
        self._objidtable = {}

        # Create list of all objects in the plist
        self._flatten(value)

        # Size of object references in serialized containers
        # depends on the number of objects in the plist.
        num_objects = len(self._objlist)
        self._object_offsets = [0]*num_objects
        self._ref_size = _count_to_size(num_objects)

        self._ref_format = _BINARY_FORMAT[self._ref_size]

        # Write file header
        self._fp.write(b'bplist00')

        # Write object list
        for obj in self._objlist:
            self._write_object(obj)

        # Write refnum->object offset table
        top_object = self._getrefnum(value)
        offset_table_offset = self._fp.tell()
        offset_size = _count_to_size(offset_table_offset)
        offset_format = '>' + _BINARY_FORMAT[offset_size] * num_objects
        self._fp.write(struct.pack(offset_format, *self._object_offsets))

        # Write trailer
        sort_version = 0
        trailer = (
            sort_version, offset_size, self._ref_size, num_objects,
            top_object, offset_table_offset
        )
        self._fp.write(struct.pack('>5xBBBQQQ', *trailer))

    def _flatten(self, value):
        # First check if the object is in the object table, not used for
        # containers to ensure that two subcontainers with the same contents
        # will be serialized as distinct values.
        if isinstance(value, _scalars):
            if (type(value), value) in self._objtable:
                return

        elif isinstance(value, plistlib.Data):
            if (type(value.data), value.data) in self._objtable:
                return

        elif id(value) in self._objidtable:
            return

        # Add to objectreference map
        refnum = len(self._objlist)
        self._objlist.append(value)
        if isinstance(value, _scalars):
            self._objtable[(type(value), value)] = refnum
        elif isinstance(value, plistlib.Data):
            self._objtable[(type(value.data), value.data)] = refnum
        else:
            self._objidtable[id(value)] = refnum

        # And finally recurse into containers
        if isinstance(value, dict):
            keys = []
            values = []
            items = value.items()
            if self._sort_keys:
                items = sorted(items)

            for k, v in items:
                if not isinstance(k, (str,unicode)):
                    if self._skipkeys:
                        continue
                    raise TypeError("keys must be strings")
                keys.append(k)
                values.append(v)

            for o in itertools.chain(keys, values):
                self._flatten(o)

        elif isinstance(value, (list, tuple)):
            for o in value:
                self._flatten(o)

    def _getrefnum(self, value):
        if isinstance(value, _scalars):
            return self._objtable[(type(value), value)]
        elif isinstance(value, plistlib.Data):
            return self._objtable[(type(value.data), value.data)]
        else:
            return self._objidtable[id(value)]

    def _write_size(self, token, size):
        if size < 15:
            self._fp.write(struct.pack('>B', token | size))

        elif size < 1 << 8:
            self._fp.write(struct.pack('>BBB', token | 0xF, 0x10, size))

        elif size < 1 << 16:
            self._fp.write(struct.pack('>BBH', token | 0xF, 0x11, size))

        elif size < 1 << 32:
            self._fp.write(struct.pack('>BBL', token | 0xF, 0x12, size))

        else:
            self._fp.write(struct.pack('>BBQ', token | 0xF, 0x13, size))

    def _write_object(self, value):
        ref = self._getrefnum(value)
        self._object_offsets[ref] = self._fp.tell()
        if value is None:
            self._fp.write(b'\x00')

        elif value is False:
            self._fp.write(b'\x08')

        elif value is True:
            self._fp.write(b'\x09')

        elif isinstance(value, int):
            if value < 0:
                try:
                    self._fp.write(struct.pack('>Bq', 0x13, value))
                except struct.error:
                    raise OverflowError(value) # from None
            elif value < 1 << 8:
                self._fp.write(struct.pack('>BB', 0x10, value))
            elif value < 1 << 16:
                self._fp.write(struct.pack('>BH', 0x11, value))
            elif value < 1 << 32:
                self._fp.write(struct.pack('>BL', 0x12, value))
            elif value < 1 << 63:
                self._fp.write(struct.pack('>BQ', 0x13, value))
            elif value < 1 << 64:
                self._fp.write(b'\x14' + value.to_bytes(16, 'big', signed=True))
            else:
                raise OverflowError(value)

        elif isinstance(value, float):
            self._fp.write(struct.pack('>Bd', 0x23, value))

        elif isinstance(value, datetime.datetime):
            f = (value - datetime.datetime(2001, 1, 1)).total_seconds()
            self._fp.write(struct.pack('>Bd', 0x33, f))

        elif isinstance(value, plistlib.Data):
            self._write_size(0x40, len(value.data))
            self._fp.write(value.data)

        elif isinstance(value, (str,unicode)):
            try:
                t = value.encode('ascii')
                self._write_size(0x50, len(value))
            except UnicodeEncodeError:
                t = value.encode('utf-16be')
                self._write_size(0x60, len(t) // 2)
            self._fp.write(t)
        
        elif isinstance(value, (bytes, bytearray)):
            self._write_size(0x40, len(value))
            self._fp.write(value)

        elif isinstance(value, (list, tuple)):
            refs = [self._getrefnum(o) for o in value]
            s = len(refs)
            self._write_size(0xA0, s)
            self._fp.write(struct.pack('>' + self._ref_format * s, *refs))

        elif isinstance(value, dict):
            keyRefs, valRefs = [], []

            if self._sort_keys:
                rootItems = sorted(value.items())
            else:
                rootItems = value.items()

            for k, v in rootItems:
                if not isinstance(k, (str,unicode)):
                    if self._skipkeys:
                        continue
                    raise TypeError("keys must be strings")
                keyRefs.append(self._getrefnum(k))
                valRefs.append(self._getrefnum(v))

            s = len(keyRefs)
            self._write_size(0xD0, s)
            self._fp.write(struct.pack('>' + self._ref_format * s, *keyRefs))
            self._fp.write(struct.pack('>' + self._ref_format * s, *valRefs))

        else:
            raise TypeError(value)
