"""Lambda function module."""

from src.config import logger
from constants import general
from constants import errors
from src import buffers_utils
from src import image_validation_logic
from src import lambda_exceptions
from src import s3
from src import status


def handler(event, context):
    """Lambda entry point."""
    allocated_buffers = None
    bucket = event['bucket']
    key = event['key']
    asset_upload_type = event['asset_upload_type']
    input_params = {
        'key': key,
        'bucket': bucket,
        'asset_upload_type': asset_upload_type
    }

    head_object_response = s3.head_object(bucket, key)

    if not head_object_response:
        lambda_exceptions.notify_and_raise(
            general.LAMBDA_NAME, general.IMAGE_VALIDATION_ERROR_STATUS,
            errors.S3_FILE_NOT_FOUND_CODE, key, bucket, {
                'key': key, 'bucket': bucket}, input_params.copy())
    try:
        if asset_upload_type != general.ASSET_UPLOAD_STATIC_ARTWORK:
            lambda_exceptions.notify_and_raise(
                general.LAMBDA_NAME, general.IMAGE_VALIDATION_ERROR_STATUS,
                errors.IMAGE_WRONG_ASSET_UPLOAD_TYPE_ERROR_CODE, key, bucket, {
                    'key': key, 'bucket': bucket, 'type': asset_upload_type},
                input_params.copy())

        allocated_buffers = buffers_utils.allocate_buffers(1)
        buffer = allocated_buffers[0]
        s3.download_file_object(bucket, key, buffer)

        image_validation_logic.validate_image(
            file_contents=buffer
        )

        status.send_general_status(
            general.LAMBDA_NAME, general.IMAGE_VALIDATION_COMPLETE_STATUS, key,
            input_params=input_params.copy(), bucket=bucket)

        return {
            **input_params,
            'is_valid': True,
        }

    except lambda_exceptions.LoggedException:
        raise
    except image_validation_logic.InvalidImageError as iie:
        status.send_general_status(
            function=general.LAMBDA_NAME,
            status=general.IMAGE_VALIDATION_ERROR_STATUS,
            filename=key,
            error_code=iie.code,
            description=str(iie),
            input_params=input_params.copy()
        )
        return {'is_valid': False}
    except Exception as e:
        logger.exception(str(e))
        lambda_exceptions.notify_and_raise(
            general.LAMBDA_NAME, general.IMAGE_VALIDATION_ERROR_STATUS,
            errors.IMAGE_VALIDATION_ERROR_CODE, key, bucket, {
                'message': str(e)},
            input_params)
    finally:
        if allocated_buffers:
            buffers_utils.release_allocated_buffers(allocated_buffers)