"""AWS client configuration with environment variable support."""

import os
from typing import Optional, Dict, Any

import boto3
from botocore.config import Config
from botocore.exceptions import ClientError, NoCredentialsError


def get_aws_config(
    region_name: Optional[str] = None,
    max_attempts: int = 3,
    mode: str = "adaptive",
) -> Config:
    """
    Get AWS client configuration.
    
    Args:
        region_name: AWS region (defaults to env var or us-east-2)
        max_attempts: Maximum retry attempts
        mode: Retry mode (standard, legacy, adaptive)
    
    Returns:
        boto3 Config object
    """
    return Config(
        region_name=region_name or os.environ.get("AWS_REGION", "us-east-2"),
        retries={"max_attempts": max_attempts, "mode": mode},
    )


def get_glue_client(
    region_name: Optional[str] = None,
    aws_access_key_id: Optional[str] = None,
    aws_secret_access_key: Optional[str] = None,
):
    """
    Create and return an AWS Glue client with environment variable support.
    
    Args:
        region_name: AWS region (defaults to AWS_REGION env var or us-east-2)
        aws_access_key_id: AWS access key (defaults to AWS_ACCESS_KEY_ID env var)
        aws_secret_access_key: AWS secret key (defaults to AWS_SECRET_ACCESS_KEY env var)
    
    Returns:
        boto3 Glue client
    
    Environment Variables:
        - AWS_REGION: AWS region (default: us-east-2)
        - AWS_ACCESS_KEY_ID: AWS access key
        - AWS_SECRET_ACCESS_KEY: AWS secret access key
    
    Example:
        >>> client = get_glue_client()
        >>> # Or with explicit credentials
        >>> client = get_glue_client(region_name="us-west-2")
    """
    config = get_aws_config(region_name=region_name)
    
    client_params = {"config": config}
   
    # Use provided credentials or fall back to environment variables
    # If neither is provided, boto3 will use default credential chain
    # (env vars, credentials file, IAM role, etc.)
    if aws_access_key_id or os.environ.get("AWS_ACCESS_KEY_ID"):
        client_params["aws_access_key_id"] = aws_access_key_id or os.environ.get("AWS_ACCESS_KEY_ID")
    
    if aws_secret_access_key or os.environ.get("AWS_SECRET_ACCESS_KEY"):
        client_params["aws_secret_access_key"] = aws_secret_access_key or os.environ.get("AWS_SECRET_ACCESS_KEY")
    
    return boto3.client("glue", **client_params)


def get_s3_client(
    region_name: Optional[str] = None,
    aws_access_key_id: Optional[str] = None,
    aws_secret_access_key: Optional[str] = None,
):
    """
    Create and return an AWS S3 client with environment variable support.
    
    Args:
        region_name: AWS region (defaults to AWS_REGION env var or us-east-2)
        aws_access_key_id: AWS access key (defaults to AWS_ACCESS_KEY_ID env var)
        aws_secret_access_key: AWS secret key (defaults to AWS_SECRET_ACCESS_KEY env var)
    
    Returns:
        boto3 S3 client
    """
    config = get_aws_config(region_name=region_name)
    
    client_params = {"config": config}
    
    if aws_access_key_id or os.environ.get("AWS_ACCESS_KEY_ID"):
        client_params["aws_access_key_id"] = aws_access_key_id or os.environ.get("AWS_ACCESS_KEY_ID")
    
    if aws_secret_access_key or os.environ.get("AWS_SECRET_ACCESS_KEY"):
        client_params["aws_secret_access_key"] = aws_secret_access_key or os.environ.get("AWS_SECRET_ACCESS_KEY")
    
    return boto3.client("s3", **client_params)


def get_lambda_client(
    region_name: Optional[str] = None,
    aws_access_key_id: Optional[str] = None,
    aws_secret_access_key: Optional[str] = None,
):
    """
    Create and return an AWS Lambda client with environment variable support.
    
    Args:
        region_name: AWS region (defaults to AWS_REGION env var or us-east-2)
        aws_access_key_id: AWS access key (defaults to AWS_ACCESS_KEY_ID env var)
        aws_secret_access_key: AWS secret key (defaults to AWS_SECRET_ACCESS_KEY env var)
    
    Returns:
        boto3 Lambda client
    """
    config = get_aws_config(region_name=region_name)
    
    client_params = {"config": config}
    
    if aws_access_key_id or os.environ.get("AWS_ACCESS_KEY_ID"):
        client_params["aws_access_key_id"] = aws_access_key_id or os.environ.get("AWS_ACCESS_KEY_ID")
    
    if aws_secret_access_key or os.environ.get("AWS_SECRET_ACCESS_KEY"):
        client_params["aws_secret_access_key"] = aws_secret_access_key or os.environ.get("AWS_SECRET_ACCESS_KEY")
    
    return boto3.client("lambda", **client_params)


    """
    Test AWS Glue client connection.
    
    Args:
        client: Optional Glue client to test (defaults to creating a new one)
    
    Returns:
        Dictionary with connection status and details
    
    Example:
        >>> result = test_glue_connection()
        >>> if result["connected"]:
        >>>     print(f"Connected to Glue in {result['region']}")
    """
    if client is None:
        client = get_glue_client()
    
    try:
        # Try to list jobs (with limit 1 to minimize API calls)
        response = client.list_jobs(MaxResults=1)
        
        return {
            "connected": True,
            "service": "glue",
            "region": client.meta.region_name,
            "message": "Successfully connected to AWS Glue",
            "jobs_found": len(response.get("JobNames", [])),
        }
    except NoCredentialsError:
        return {
            "connected": False,
            "service": "glue",
            "error": "No AWS credentials found",
            "message": "Please set AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables",
        }
    except ClientError as e:
        return {
            "connected": False,
            "service": "glue",
            "error": str(e),
            "error_code": e.response.get("Error", {}).get("Code"),
            "message": f"Failed to connect to AWS Glue: {e}",
        }
    except Exception as e:
        return {
            "connected": False,
            "service": "glue",
            "error": str(e),
            "message": f"Unexpected error connecting to AWS Glue: {e}",
        }


    """
    Test AWS S3 client connection.
    
    Args:
        client: Optional S3 client to test (defaults to creating a new one)
    
    Returns:
        Dictionary with connection status and details
    
    Example:
        >>> result = test_s3_connection()
        >>> if result["connected"]:
        >>>     print(f"Connected to S3 in {result['region']}")
    """
    if client is None:
        client = get_s3_client()
    
    try:
        # Try to list buckets
        response = client.list_buckets()
        
        return {
            "connected": True,
            "service": "s3",
            "region": client.meta.region_name,
            "message": "Successfully connected to AWS S3",
            "buckets_found": len(response.get("Buckets", [])),
        }
    except NoCredentialsError:
        return {
            "connected": False,
            "service": "s3",
            "error": "No AWS credentials found",
            "message": "Please set AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables",
        }
    except ClientError as e:
        return {
            "connected": False,
            "service": "s3",
            "error": str(e),
            "error_code": e.response.get("Error", {}).get("Code"),
            "message": f"Failed to connect to AWS S3: {e}",
        }
    except Exception as e:
        return {
            "connected": False,
            "service": "s3",
            "error": str(e),
            "message": f"Unexpected error connecting to AWS S3: {e}",
        }


    """
    Test all AWS client connections.
    
    Returns:
        Dictionary with connection status for all services
    
    Example:
        >>> results = test_all_connections()
        >>> for service, result in results.items():
        >>>     print(f"{service}: {'✓' if result['connected'] else '✗'}")
    """
    return {
        "glue": test_glue_connection(),
        "s3": test_s3_connection(),
    }


# Default clients using environment variables
# These maintain backward compatibility with existing code
glue_client = get_glue_client(region_name="us-east-2")
s3_client = get_s3_client()
lambda_client = get_lambda_client()


__all__ = [
    "glue_client",
    "s3_client", 
    "lambda_client",
    "get_glue_client",
    "get_s3_client",
    "get_lambda_client",
    "get_aws_config",
]