# -*- coding: utf-8 -*-

# Copyright 2020 Google LLC
#
# 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.
#

import warnings
from typing import Callable, Dict, Optional, Sequence, Tuple

from google.api_core import grpc_helpers  # type: ignore
from google.api_core import gapic_v1  # type: ignore
from google import auth  # type: ignore
from google.auth import credentials  # type: ignore
from google.auth.transport.grpc import SslCredentials  # type: ignore

import grpc  # type: ignore

from google.cloud.bigquery_storage_v1beta2.types import storage
from google.cloud.bigquery_storage_v1beta2.types import stream

from .base import BigQueryWriteTransport, DEFAULT_CLIENT_INFO


class BigQueryWriteGrpcTransport(BigQueryWriteTransport):
    """gRPC backend transport for BigQueryWrite.

    BigQuery Write API.
    The Write API can be used to write data to BigQuery.

    This class defines the same methods as the primary client, so the
    primary client can load the underlying transport implementation
    and call it.

    It sends protocol buffers over the wire using gRPC (which is built on
    top of HTTP/2); the ``grpcio`` package must be installed.
    """

    _stubs: Dict[str, Callable]

    def __init__(
        self,
        *,
        host: str = "bigquerystorage.googleapis.com",
        credentials: credentials.Credentials = None,
        credentials_file: str = None,
        scopes: Sequence[str] = None,
        channel: grpc.Channel = None,
        api_mtls_endpoint: str = None,
        client_cert_source: Callable[[], Tuple[bytes, bytes]] = None,
        ssl_channel_credentials: grpc.ChannelCredentials = None,
        quota_project_id: Optional[str] = None,
        client_info: gapic_v1.client_info.ClientInfo = DEFAULT_CLIENT_INFO,
    ) -> None:
        """Instantiate the transport.

        Args:
            host (Optional[str]): The hostname to connect to.
            credentials (Optional[google.auth.credentials.Credentials]): The
                authorization credentials to attach to requests. These
                credentials identify the application to the service; if none
                are specified, the client will attempt to ascertain the
                credentials from the environment.
                This argument is ignored if ``channel`` is provided.
            credentials_file (Optional[str]): A file with credentials that can
                be loaded with :func:`google.auth.load_credentials_from_file`.
                This argument is ignored if ``channel`` is provided.
            scopes (Optional(Sequence[str])): A list of scopes. This argument is
                ignored if ``channel`` is provided.
            channel (Optional[grpc.Channel]): A ``Channel`` instance through
                which to make calls.
            api_mtls_endpoint (Optional[str]): Deprecated. The mutual TLS endpoint.
                If provided, it overrides the ``host`` argument and tries to create
                a mutual TLS channel with client SSL credentials from
                ``client_cert_source`` or applicatin default SSL credentials.
            client_cert_source (Optional[Callable[[], Tuple[bytes, bytes]]]):
                Deprecated. A callback to provide client SSL certificate bytes and
                private key bytes, both in PEM format. It is ignored if
                ``api_mtls_endpoint`` is None.
            ssl_channel_credentials (grpc.ChannelCredentials): SSL credentials
                for grpc channel. It is ignored if ``channel`` is provided.
            quota_project_id (Optional[str]): An optional project to use for billing
                and quota.
            client_info (google.api_core.gapic_v1.client_info.ClientInfo):
                The client info used to send a user-agent string along with
                API requests. If ``None``, then default info will be used.
                Generally, you only need to set this if you're developing
                your own client library.

        Raises:
          google.auth.exceptions.MutualTLSChannelError: If mutual TLS transport
              creation failed for any reason.
          google.api_core.exceptions.DuplicateCredentialArgs: If both ``credentials``
              and ``credentials_file`` are passed.
        """
        self._ssl_channel_credentials = ssl_channel_credentials

        if channel:
            # Sanity check: Ensure that channel and credentials are not both
            # provided.
            credentials = False

            # If a channel was explicitly provided, set it.
            self._grpc_channel = channel
            self._ssl_channel_credentials = None
        elif api_mtls_endpoint:
            warnings.warn(
                "api_mtls_endpoint and client_cert_source are deprecated",
                DeprecationWarning,
            )

            host = (
                api_mtls_endpoint
                if ":" in api_mtls_endpoint
                else api_mtls_endpoint + ":443"
            )

            if credentials is None:
                credentials, _ = auth.default(
                    scopes=self.AUTH_SCOPES, quota_project_id=quota_project_id
                )

            # Create SSL credentials with client_cert_source or application
            # default SSL credentials.
            if client_cert_source:
                cert, key = client_cert_source()
                ssl_credentials = grpc.ssl_channel_credentials(
                    certificate_chain=cert, private_key=key
                )
            else:
                ssl_credentials = SslCredentials().ssl_credentials

            # create a new channel. The provided one is ignored.
            self._grpc_channel = type(self).create_channel(
                host,
                credentials=credentials,
                credentials_file=credentials_file,
                ssl_credentials=ssl_credentials,
                scopes=scopes or self.AUTH_SCOPES,
                quota_project_id=quota_project_id,
                options=[
                    ("grpc.max_send_message_length", -1),
                    ("grpc.max_receive_message_length", -1),
                ],
            )
            self._ssl_channel_credentials = ssl_credentials
        else:
            host = host if ":" in host else host + ":443"

            if credentials is None:
                credentials, _ = auth.default(
                    scopes=self.AUTH_SCOPES, quota_project_id=quota_project_id
                )

            # create a new channel. The provided one is ignored.
            self._grpc_channel = type(self).create_channel(
                host,
                credentials=credentials,
                credentials_file=credentials_file,
                ssl_credentials=ssl_channel_credentials,
                scopes=scopes or self.AUTH_SCOPES,
                quota_project_id=quota_project_id,
                options=[
                    ("grpc.max_send_message_length", -1),
                    ("grpc.max_receive_message_length", -1),
                ],
            )

        self._stubs = {}  # type: Dict[str, Callable]

        # Run the base constructor.
        super().__init__(
            host=host,
            credentials=credentials,
            credentials_file=credentials_file,
            scopes=scopes or self.AUTH_SCOPES,
            quota_project_id=quota_project_id,
            client_info=client_info,
        )

    @classmethod
    def create_channel(
        cls,
        host: str = "bigquerystorage.googleapis.com",
        credentials: credentials.Credentials = None,
        credentials_file: str = None,
        scopes: Optional[Sequence[str]] = None,
        quota_project_id: Optional[str] = None,
        **kwargs,
    ) -> grpc.Channel:
        """Create and return a gRPC channel object.
        Args:
            address (Optional[str]): The host for the channel to use.
            credentials (Optional[~.Credentials]): The
                authorization credentials to attach to requests. These
                credentials identify this application to the service. If
                none are specified, the client will attempt to ascertain
                the credentials from the environment.
            credentials_file (Optional[str]): A file with credentials that can
                be loaded with :func:`google.auth.load_credentials_from_file`.
                This argument is mutually exclusive with credentials.
            scopes (Optional[Sequence[str]]): A optional list of scopes needed for this
                service. These are only used when credentials are not specified and
                are passed to :func:`google.auth.default`.
            quota_project_id (Optional[str]): An optional project to use for billing
                and quota.
            kwargs (Optional[dict]): Keyword arguments, which are passed to the
                channel creation.
        Returns:
            grpc.Channel: A gRPC channel object.

        Raises:
            google.api_core.exceptions.DuplicateCredentialArgs: If both ``credentials``
              and ``credentials_file`` are passed.
        """
        scopes = scopes or cls.AUTH_SCOPES
        return grpc_helpers.create_channel(
            host,
            credentials=credentials,
            credentials_file=credentials_file,
            scopes=scopes,
            quota_project_id=quota_project_id,
            **kwargs,
        )

    @property
    def grpc_channel(self) -> grpc.Channel:
        """Return the channel designed to connect to this service.
        """
        return self._grpc_channel

    @property
    def create_write_stream(
        self,
    ) -> Callable[[storage.CreateWriteStreamRequest], stream.WriteStream]:
        r"""Return a callable for the create write stream method over gRPC.

        Creates a write stream to the given table. Additionally, every
        table has a special COMMITTED stream named '_default' to which
        data can be written. This stream doesn't need to be created
        using CreateWriteStream. It is a stream that can be used
        simultaneously by any number of clients. Data written to this
        stream is considered committed as soon as an acknowledgement is
        received.

        Returns:
            Callable[[~.CreateWriteStreamRequest],
                    ~.WriteStream]:
                A function that, when called, will call the underlying RPC
                on the server.
        """
        # Generate a "stub function" on-the-fly which will actually make
        # the request.
        # gRPC handles serialization and deserialization, so we just need
        # to pass in the functions for each.
        if "create_write_stream" not in self._stubs:
            self._stubs["create_write_stream"] = self.grpc_channel.unary_unary(
                "/google.cloud.bigquery.storage.v1beta2.BigQueryWrite/CreateWriteStream",
                request_serializer=storage.CreateWriteStreamRequest.serialize,
                response_deserializer=stream.WriteStream.deserialize,
            )
        return self._stubs["create_write_stream"]

    @property
    def append_rows(
        self,
    ) -> Callable[[storage.AppendRowsRequest], storage.AppendRowsResponse]:
        r"""Return a callable for the append rows method over gRPC.

        Appends data to the given stream.

        If ``offset`` is specified, the ``offset`` is checked against
        the end of stream. The server returns ``OUT_OF_RANGE`` in
        ``AppendRowsResponse`` if an attempt is made to append to an
        offset beyond the current end of the stream or
        ``ALREADY_EXISTS`` if user provids an ``offset`` that has
        already been written to. User can retry with adjusted offset
        within the same RPC stream. If ``offset`` is not specified,
        append happens at the end of the stream.

        The response contains the offset at which the append happened.
        Responses are received in the same order in which requests are
        sent. There will be one response for each successful request. If
        the ``offset`` is not set in response, it means append didn't
        happen due to some errors. If one request fails, all the
        subsequent requests will also fail until a success request is
        made again.

        If the stream is of ``PENDING`` type, data will only be
        available for read operations after the stream is committed.

        Returns:
            Callable[[~.AppendRowsRequest],
                    ~.AppendRowsResponse]:
                A function that, when called, will call the underlying RPC
                on the server.
        """
        # Generate a "stub function" on-the-fly which will actually make
        # the request.
        # gRPC handles serialization and deserialization, so we just need
        # to pass in the functions for each.
        if "append_rows" not in self._stubs:
            self._stubs["append_rows"] = self.grpc_channel.stream_stream(
                "/google.cloud.bigquery.storage.v1beta2.BigQueryWrite/AppendRows",
                request_serializer=storage.AppendRowsRequest.serialize,
                response_deserializer=storage.AppendRowsResponse.deserialize,
            )
        return self._stubs["append_rows"]

    @property
    def get_write_stream(
        self,
    ) -> Callable[[storage.GetWriteStreamRequest], stream.WriteStream]:
        r"""Return a callable for the get write stream method over gRPC.

        Gets a write stream.

        Returns:
            Callable[[~.GetWriteStreamRequest],
                    ~.WriteStream]:
                A function that, when called, will call the underlying RPC
                on the server.
        """
        # Generate a "stub function" on-the-fly which will actually make
        # the request.
        # gRPC handles serialization and deserialization, so we just need
        # to pass in the functions for each.
        if "get_write_stream" not in self._stubs:
            self._stubs["get_write_stream"] = self.grpc_channel.unary_unary(
                "/google.cloud.bigquery.storage.v1beta2.BigQueryWrite/GetWriteStream",
                request_serializer=storage.GetWriteStreamRequest.serialize,
                response_deserializer=stream.WriteStream.deserialize,
            )
        return self._stubs["get_write_stream"]

    @property
    def finalize_write_stream(
        self,
    ) -> Callable[
        [storage.FinalizeWriteStreamRequest], storage.FinalizeWriteStreamResponse
    ]:
        r"""Return a callable for the finalize write stream method over gRPC.

        Finalize a write stream so that no new data can be appended to
        the stream. Finalize is not supported on the '_default' stream.

        Returns:
            Callable[[~.FinalizeWriteStreamRequest],
                    ~.FinalizeWriteStreamResponse]:
                A function that, when called, will call the underlying RPC
                on the server.
        """
        # Generate a "stub function" on-the-fly which will actually make
        # the request.
        # gRPC handles serialization and deserialization, so we just need
        # to pass in the functions for each.
        if "finalize_write_stream" not in self._stubs:
            self._stubs["finalize_write_stream"] = self.grpc_channel.unary_unary(
                "/google.cloud.bigquery.storage.v1beta2.BigQueryWrite/FinalizeWriteStream",
                request_serializer=storage.FinalizeWriteStreamRequest.serialize,
                response_deserializer=storage.FinalizeWriteStreamResponse.deserialize,
            )
        return self._stubs["finalize_write_stream"]

    @property
    def batch_commit_write_streams(
        self,
    ) -> Callable[
        [storage.BatchCommitWriteStreamsRequest],
        storage.BatchCommitWriteStreamsResponse,
    ]:
        r"""Return a callable for the batch commit write streams method over gRPC.

        Atomically commits a group of ``PENDING`` streams that belong to
        the same ``parent`` table. Streams must be finalized before
        commit and cannot be committed multiple times. Once a stream is
        committed, data in the stream becomes available for read
        operations.

        Returns:
            Callable[[~.BatchCommitWriteStreamsRequest],
                    ~.BatchCommitWriteStreamsResponse]:
                A function that, when called, will call the underlying RPC
                on the server.
        """
        # Generate a "stub function" on-the-fly which will actually make
        # the request.
        # gRPC handles serialization and deserialization, so we just need
        # to pass in the functions for each.
        if "batch_commit_write_streams" not in self._stubs:
            self._stubs["batch_commit_write_streams"] = self.grpc_channel.unary_unary(
                "/google.cloud.bigquery.storage.v1beta2.BigQueryWrite/BatchCommitWriteStreams",
                request_serializer=storage.BatchCommitWriteStreamsRequest.serialize,
                response_deserializer=storage.BatchCommitWriteStreamsResponse.deserialize,
            )
        return self._stubs["batch_commit_write_streams"]

    @property
    def flush_rows(
        self,
    ) -> Callable[[storage.FlushRowsRequest], storage.FlushRowsResponse]:
        r"""Return a callable for the flush rows method over gRPC.

        Flushes rows to a BUFFERED stream. If users are appending rows
        to BUFFERED stream, flush operation is required in order for the
        rows to become available for reading. A Flush operation flushes
        up to any previously flushed offset in a BUFFERED stream, to the
        offset specified in the request. Flush is not supported on the
        \_default stream, since it is not BUFFERED.

        Returns:
            Callable[[~.FlushRowsRequest],
                    ~.FlushRowsResponse]:
                A function that, when called, will call the underlying RPC
                on the server.
        """
        # Generate a "stub function" on-the-fly which will actually make
        # the request.
        # gRPC handles serialization and deserialization, so we just need
        # to pass in the functions for each.
        if "flush_rows" not in self._stubs:
            self._stubs["flush_rows"] = self.grpc_channel.unary_unary(
                "/google.cloud.bigquery.storage.v1beta2.BigQueryWrite/FlushRows",
                request_serializer=storage.FlushRowsRequest.serialize,
                response_deserializer=storage.FlushRowsResponse.deserialize,
            )
        return self._stubs["flush_rows"]


__all__ = ("BigQueryWriteGrpcTransport",)
