"""S3 common functions."""

import boto3
import botocore

from config import logger

client = boto3.client('s3')
resource = boto3.resource('s3')


def put_object(bucket, key, data, **kwargs):
    """Put object to S3.

    Args:
        bucket (str): target S3 bucket.
        key (str): target S3 key.
        data (bytes): file data.
        kwargs (dict): extra arguments.
    """
    return client.put_object(Bucket=bucket, Key=key, Body=data, **kwargs)


def get_object(bucket, key):
    """Get S3 object.

    Args:
        bucket (str): target S3 bucket.
        key (str): target S3 key.
    """
    return client.get_object(Bucket=bucket, Key=key)


def object_exists(bucket, key):
    """Check if S3 object exists.

    Args:
        bucket (str): target S3 bucket.
        key (str): target S3 key.
    """
    try:
        client.head_object(Bucket=bucket, Key=key)
    except botocore.exceptions.ClientError as e:
        if e.response['Error']['Code'] == '404':
            return False
        else:
            raise
    else:
        return True


def head_object(bucket, key):
    """Retrieve object metadata without object downloading.

    Args:
        bucket (str): target S3 bucket.
        key (str): target object key.

    Returns:
        dict: Response from S3.

    """
    return client.head_object(Bucket=bucket, Key=key)


def download_file_object(bucket, key, file_object, **kwargs):
    """Download s3 object to file-like buffer.

    Args:
        bucket (str): target S3 bucket.
        key (str): target S3 key.
        file_object (io.BytesIO): file data.
        kwargs (dict): extra arguments.
    """
    return client.download_fileobj(
        Bucket=bucket, Key=key, Fileobj=file_object, **kwargs)


def upload_file_objects(file_descriptors, bucket,
                        content_type='binary/octet'):
    """Upload file objects to s3.

    Args:
        file_descriptors (list): List of file descriptors.
        bucket (str): target S3 bucket.
        content_type (str): Content Type
    """
    try:
        for descriptor in file_descriptors:
            descriptor['output_image_buffer'].seek(0)
            put_object(
                bucket=bucket, key=descriptor['key'],
                data=descriptor['output_image_buffer'],
                ContentType=content_type
            )
    except Exception as e:
        logger.exception(str(e))
        raise
    return True


def create_presigned_url(
        bucket, key, client_method='get_object', expires_in=86400):
    """Generate a presigned url.

    Args:
        bucket (str): Bucket name.
        key (str): Existing S3 object key.
        client_method (str): Client method for operation by result URL.
        expires_in (int):  The number of seconds the presigned url is valid
            for. By default it expires in 24 hours (86400 seconds).

    Returns:
        str: Presigned url.

    """
    return client.generate_presigned_url(
        ClientMethod=client_method,
        ExpiresIn=expires_in,
        Params={
            'Bucket': bucket,
            'Key': key
        }
    )


def copy_object(source_bucket, source_key, destination_bucket, destination_key,
                destination_metadata):
    """Copy S3 object from one bucket to another.

    Args:
        source_bucket (str): Bucket name for source S3 object.
        source_key (str): Key name of the source S3 object.
        destination_bucket (str):Bucket name for destination S3 object.
        destination_key (str):  Key name of the destination S3 object.
        destination_metadata (dict): Metadata for destination object.

    Returns:
        dict: Response from S3.

    """
    return client.copy_object(
        Bucket=destination_bucket, Key=destination_key,
        CopySource={'Bucket': source_bucket, 'Key': source_key},
        Metadata=destination_metadata)