# This is a backport of the Python2.5 uuid module.

# IMPORTANT NOTE: All references to ctypes are commented out because
#                 ctypes does all sorts of strange things that makes
#                 it not work in httpd with SELinux enabled.

r"""UUID objects (universally unique identifiers) according to RFC 4122.

This module provides immutable UUID objects (class UUID) and the functions
uuid1(), uuid3(), uuid4(), uuid5() for generating version 1, 3, 4, and 5
UUIDs as specified in RFC 4122.

If all you want is a unique ID, you should probably call uuid1() or uuid4().
Note that uuid1() may compromise privacy since it creates a UUID containing
the computer's network address.  uuid4() creates a random UUID.

Typical usage:

    **Important:** So that the freeIPA Python 2.4 ``uuid`` backport can be
    automatically loaded when needed, import the ``uuid`` module like this:

    >>> from ipalib import uuid

    Make a UUID based on the host ID and current time:

    >>> uuid.uuid1()  #doctest: +ELLIPSIS
    UUID('...')

    Make a UUID using an MD5 hash of a namespace UUID and a name:

    >>> uuid.uuid3(uuid.NAMESPACE_DNS, 'python.org')
    UUID('6fa459ea-ee8a-3ca4-894e-db77e160355e')

    Make a random UUID:

    >>> uuid.uuid4()  #doctest: +ELLIPSIS
    UUID('...')

    Make a UUID using a SHA-1 hash of a namespace UUID and a name:

    >>> uuid.uuid5(uuid.NAMESPACE_DNS, 'python.org')
    UUID('886313e1-3b8a-5372-9b90-0c9aee199e5d')

    Make a UUID from a string of hex digits (braces and hyphens ignored):

    >>> x = uuid.UUID('{00010203-0405-0607-0809-0a0b0c0d0e0f}')
    >>> x
    UUID('00010203-0405-0607-0809-0a0b0c0d0e0f')

    Convert a UUID to a string of hex digits in standard form:

    >>> str(x)
    '00010203-0405-0607-0809-0a0b0c0d0e0f'

    Get the raw 16 bytes of the UUID:

    >>> x.bytes
    '\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f'

    Make a UUID from a 16-byte string:

    >>> uuid.UUID(bytes=x.bytes)
    UUID('00010203-0405-0607-0809-0a0b0c0d0e0f')
"""

__author__ = 'Ka-Ping Yee <ping@zesty.ca>'

RESERVED_NCS, RFC_4122, RESERVED_MICROSOFT, RESERVED_FUTURE = [
    'reserved for NCS compatibility', 'specified in RFC 4122',
    'reserved for Microsoft compatibility', 'reserved for future definition']

class UUID(object):
    """Instances of the UUID class represent UUIDs as specified in RFC 4122.
    UUID objects are immutable, hashable, and usable as dictionary keys.
    Converting a UUID to a string with str() yields something in the form
    '12345678-1234-1234-1234-123456789abc'.  The UUID constructor accepts
    five possible forms: a similar string of hexadecimal digits, or a tuple
    of six integer fields (with 32-bit, 16-bit, 16-bit, 8-bit, 8-bit, and
    48-bit values respectively) as an argument named 'fields', or a string
    of 16 bytes (with all the integer fields in big-endian order) as an
    argument named 'bytes', or a string of 16 bytes (with the first three
    fields in little-endian order) as an argument named 'bytes_le', or a
    single 128-bit integer as an argument named 'int'.

    UUIDs have these read-only attributes:

        bytes       the UUID as a 16-byte string (containing the six
                    integer fields in big-endian byte order)

        bytes_le    the UUID as a 16-byte string (with time_low, time_mid,
                    and time_hi_version in little-endian byte order)

        fields      a tuple of the six integer fields of the UUID,
                    which are also available as six individual attributes
                    and two derived attributes:

            time_low                the first 32 bits of the UUID
            time_mid                the next 16 bits of the UUID
            time_hi_version         the next 16 bits of the UUID
            clock_seq_hi_variant    the next 8 bits of the UUID
            clock_seq_low           the next 8 bits of the UUID
            node                    the last 48 bits of the UUID

            time                    the 60-bit timestamp
            clock_seq               the 14-bit sequence number

        hex         the UUID as a 32-character hexadecimal string

        int         the UUID as a 128-bit integer

        urn         the UUID as a URN as specified in RFC 4122

        variant     the UUID variant (one of the constants RESERVED_NCS,
                    RFC_4122, RESERVED_MICROSOFT, or RESERVED_FUTURE)

        version     the UUID version number (1 through 5, meaningful only
                    when the variant is RFC_4122)
    """

    def __init__(self, hex=None, bytes=None, bytes_le=None, fields=None,
                       int=None, version=None):
        r"""Create a UUID from either a string of 32 hexadecimal digits,
        a string of 16 bytes as the 'bytes' argument, a string of 16 bytes
        in little-endian order as the 'bytes_le' argument, a tuple of six
        integers (32-bit time_low, 16-bit time_mid, 16-bit time_hi_version,
        8-bit clock_seq_hi_variant, 8-bit clock_seq_low, 48-bit node) as
        the 'fields' argument, or a single 128-bit integer as the 'int'
        argument.  When a string of hex digits is given, curly braces,
        hyphens, and a URN prefix are all optional.  For example, these
        expressions all yield the same UUID:

        UUID('{12345678-1234-5678-1234-567812345678}')
        UUID('12345678123456781234567812345678')
        UUID('urn:uuid:12345678-1234-5678-1234-567812345678')
        UUID(bytes='\x12\x34\x56\x78'*4)
        UUID(bytes_le='\x78\x56\x34\x12\x34\x12\x78\x56' +
                      '\x12\x34\x56\x78\x12\x34\x56\x78')
        UUID(fields=(0x12345678, 0x1234, 0x5678, 0x12, 0x34, 0x567812345678))
        UUID(int=0x12345678123456781234567812345678)

        Exactly one of 'hex', 'bytes', 'bytes_le', 'fields', or 'int' must
        be given.  The 'version' argument is optional; if given, the resulting
        UUID will have its variant and version set according to RFC 4122,
        overriding the given 'hex', 'bytes', 'bytes_le', 'fields', or 'int'.
        """

        if [hex, bytes, bytes_le, fields, int].count(None) != 4:
            raise TypeError('need one of hex, bytes, bytes_le, fields, or int')
        if hex is not None:
            hex = hex.replace('urn:', '').replace('uuid:', '')
            hex = hex.strip('{}').replace('-', '')
            if len(hex) != 32:
                raise ValueError('badly formed hexadecimal UUID string')
            int = long(hex, 16)
        if bytes_le is not None:
            if len(bytes_le) != 16:
                raise ValueError('bytes_le is not a 16-char string')
            bytes = (bytes_le[3] + bytes_le[2] + bytes_le[1] + bytes_le[0] +
                     bytes_le[5] + bytes_le[4] + bytes_le[7] + bytes_le[6] +
                     bytes_le[8:])
        if bytes is not None:
            if len(bytes) != 16:
                raise ValueError('bytes is not a 16-char string')
            int = long(('%02x'*16) % tuple(map(ord, bytes)), 16)
        if fields is not None:
            if len(fields) != 6:
                raise ValueError('fields is not a 6-tuple')
            (time_low, time_mid, time_hi_version,
             clock_seq_hi_variant, clock_seq_low, node) = fields
            if not 0 <= time_low < 1<<32L:
                raise ValueError('field 1 out of range (need a 32-bit value)')
            if not 0 <= time_mid < 1<<16L:
                raise ValueError('field 2 out of range (need a 16-bit value)')
            if not 0 <= time_hi_version < 1<<16L:
                raise ValueError('field 3 out of range (need a 16-bit value)')
            if not 0 <= clock_seq_hi_variant < 1<<8L:
                raise ValueError('field 4 out of range (need an 8-bit value)')
            if not 0 <= clock_seq_low < 1<<8L:
                raise ValueError('field 5 out of range (need an 8-bit value)')
            if not 0 <= node < 1<<48L:
                raise ValueError('field 6 out of range (need a 48-bit value)')