# Source code for cassandra.encoder

    # Copyright DataStax, Inc.
    #
    # Licensed under the Apache License, Version 2.0 (the "License");
    # you may not use this file except in compliance with the License.
    # You may obtain a copy of the License at
    #
    # http://www.apache.org/licenses/LICENSE-2.0
    #
    # Unless required by applicable law or agreed to in writing, software
    # distributed under the License is distributed on an "AS IS" BASIS,
    # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    # See the License for the specific language governing permissions and
    # limitations under the License.
    """
    These functions are used to convert Python objects into CQL strings.
    When non-prepared statements are executed, these encoder functions are
    called on each query parameter.
    """

    import logging
    log = logging.getLogger(__name__)

    from binascii import hexlify
    import calendar
    import datetime
    import math
    import sys
    import types
    from uuid import UUID
    import ipaddress

    from cassandra.util import (OrderedDict, OrderedMap, OrderedMapSerializedKey,
                                sortedset, Time, Date, Point, LineString, Polygon)

    def cql_quote(term):
        if isinstance(term, str):
            return "'%s'" % str(term).replace("'", "''")
        else:
            return str(term)

    class ValueSequence(list):
        pass

    class Encoder(object):
        """
        A container for mapping python types to CQL string literals when working
        with non-prepared statements.  The type :attr:`~.Encoder.mapping` can be
        directly customized by users.
        """

        mapping = None
        """
        A map of python types to encoder functions.
        """

        def __init__(self):
            self.mapping = {
                float: self.cql_encode_float,
                bytearray: self.cql_encode_bytes,
                str: self.cql_encode_str,
                int: self.cql_encode_object,
                UUID: self.cql_encode_object,
                datetime.datetime: self.cql_encode_datetime,
                datetime.date: self.cql_encode_date,
                datetime.time: self.cql_encode_time,
                Date: self.cql_encode_date_ext,
                Time: self.cql_encode_time,
                dict: self.cql_encode_map_collection,
                OrderedDict: self.cql_encode_map_collection,
                OrderedMap: self.cql_encode_map_collection,
                OrderedMapSerializedKey: self.cql_encode_map_collection,
                list: self.cql_encode_list_collection,
                tuple: self.cql_encode_list_collection,  # TODO: change to tuple in next major
                set: self.cql_encode_set_collection,
                sortedset: self.cql_encode_set_collection,
                frozenset: self.cql_encode_set_collection,
                types.GeneratorType: self.cql_encode_list_collection,
                ValueSequence: self.cql_encode_sequence,
                Point: self.cql_encode_str_quoted,
                LineString: self.cql_encode_str_quoted,
                Polygon: self.cql_encode_str_quoted
            }

            self.mapping.update({
                memoryview: self.cql_encode_bytes,
                bytes: self.cql_encode_bytes,
                type(None): self.cql_encode_none,
                ipaddress.IPv4Address: self.cql_encode_ipaddress,
                ipaddress.IPv6Address: self.cql_encode_ipaddress
            })

        def cql_encode_none(self, val):
            """
            Converts :const:`None` to the string 'NULL'.
            """
            return 'NULL'

        def cql_encode_unicode(self, val):
            """
            Converts :class:`unicode` objects to UTF-8 encoded strings with quote escaping.
            """
            return cql_quote(val.encode('utf-8'))

        def cql_encode_str(self, val):
            """
            Escapes quotes in :class:`str` objects.
            """
            return cql_quote(val)

        def cql_encode_str_quoted(self, val):
            return "'%s'" % val

        def cql_encode_bytes(self, val):
            return (b'0x' + hexlify(val)).decode('utf-8')

        def cql_encode_object(self, val):
            """
            Default encoder for all objects that do not have a specific encoder function
            registered. This function simply calls :meth:`str()` on the object.
            """
            return str(val)

        def cql_encode_float(self, val):
            """
            Encode floats using repr to preserve precision
            """
            if math.isinf(val):
                return 'Infinity' if val > 0 else '-Infinity'
            elif math.isnan(val):
                return 'NaN'
            else:
                return repr(val)

        def cql_encode_datetime(self, val):
            """
            Converts a :class:`datetime.datetime` object to a (string) integer timestamp
            with millisecond precision.
            """
            timestamp = calendar.timegm(val.utctimetuple())
            return str(int(timestamp * 1e3 + getattr(val, 'microsecond', 0) / 1e3))

        def cql_encode_date(self, val):
            """
            Converts a :class:`datetime.date` object to a string with format
            ``YYYY-MM-DD``.
            """
            return "'%s'" % val.strftime('%Y-%m-%d')

        def cql_encode_time(self, val):
            """
            Converts a :class:`cassandra.util.Time` object to a string with format
            ``HH:MM:SS.mmmuuunnn``.
            """
            return "'%s'" % val

        def cql_encode_date_ext(self, val):
            """
            Encodes a :class:`cassandra.util.Date` object as an integer
            """
            # using the int form in case the Date exceeds datetime.[MIN|MAX]YEAR
            return str(val.days_from_epoch + 2 ** 31)

        def cql_encode_sequence(self, val):
            """
            Converts a sequence to a string of the form ``(item1, item2, ...)``.  This
            is suitable for ``IN`` value lists.
            """
            return '(%s)' % ', '.join(self.mapping.get(type(v), self.cql_encode_object)(v)
                                         for v in val)

        cql_encode_tuple = cql_encode_sequence
        """
        Converts a sequence to a string of the form ``(item1, item2, ...)``.  This
        is suitable for ``tuple`` type columns.
        """

        def cql_encode_map_collection(self, val):
            """
            Converts a dict into a string of the form ``{key1: val1, key2: val2, ...}``.
            This is suitable for ``map`` type columns.
            """
            return '{%s}' % ', '.join('%s: %s' % (
                self.mapping.get(type(k), self.cql_encode_object)(k),
                self.mapping.get(type(v), self.cql_encode_object)(v)
            ) for k, v in val.items())

        def cql_encode_list_collection(self, val):
            """
            Converts a sequence to a string of the form ``[item1, item2, ...]``.  This
            is suitable for ``list`` type columns.
            """
            return '[%s]' % ', '.join(self.mapping.get(type(v), self.cql_encode_object)(v) for v in val)

        def cql_encode_set_collection(self, val):
            """
            Converts a sequence to a string of the form ``{item1, item2, ...}``.  This
            is suitable for ``set`` type columns.
            """
            return '{%s}' % ', '.join(self.mapping.get(type(v), self.cql_encode_object)(v) for v in val)

        def cql_encode_all_types(self, val, as_text_type=False):
            """
            Converts any type into a CQL string, defaulting to ``cql_encode_object``
            if :attr:`~Encoder.mapping` does not contain an entry for the type.
            """
            encoded = self.mapping.get(type(val), self.cql_encode_object)(val)
            if as_text_type and not isinstance(encoded, str):
                return encoded.decode('utf-8')
            return encoded

        def cql_encode_ipaddress(self, val):
            """
            Converts an ipaddress (IPV4Address, IPV6Address) to a CQL string. This
            is suitable for ``inet`` type columns.
            """
            return "'%s'" % val.compressed