"""
Copyright 2022 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

  https://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 ssl
from typing import Any, TYPE_CHECKING

SERVER_PROXY_PORT = 3307

if TYPE_CHECKING:
    import asyncpg


async def connect(
    ip_address: str, ctx: ssl.SSLContext, **kwargs: Any
) -> "asyncpg.Connection":
    """Helper function to create an asyncpg DB-API connection object.

    Args:
        ip_address (str): A string containing an IP address for the Cloud SQL
            instance.
        ctx (ssl.SSLContext): An SSLContext object created from the Cloud SQL
            server CA cert and ephemeral cert.
            server CA cert and ephemeral cert.
        kwargs: Keyword arguments for establishing asyncpg connection
            object to Cloud SQL instance.

    Returns:
        asyncpg.Connection: An asyncpg connection to the Cloud SQL
            instance.
    Raises:
        ImportError: The asyncpg module cannot be imported.
    """

    try:
        import asyncpg
    except ImportError:
        raise ImportError(
            'Unable to import module "asyncpg." Please install and try again.'
        )
    user = kwargs.pop("user")
    db = kwargs.pop("db")
    passwd = kwargs.pop("password", None)

    return await asyncpg.connect(
        user=user,
        database=db,
        password=passwd,
        host=ip_address,
        port=SERVER_PROXY_PORT,
        ssl=ctx,
        direct_tls=True,
        **kwargs,
    )