"""Utils for make ready flask response values."""
from ows_accounting.constants import pagination


def add_pagination(items, limit=0, offset=0,
                   pagination_type=pagination.TYPE_NONE):
    """Add pagination to the list of items objects.
    Paginate items if necessary depend on pagination_type.

    Args:
        items (list):  list of items objects.
        limit (int):  limit number of result records.
        offset (int):  offset start of result records.
        pagination_type (string): all variants are in
            pagination.TYPE_TO_RETURN_MAPPING

    Returns:
        response: Paginated list of objects.
    """
    total_records = len(items)
    return_pagination_type = pagination.TYPE_TO_RETURN_MAPPING[
        pagination_type]
    pagination_dict = {
        'items': items,
        'pagination': {
            'type': return_pagination_type,
            'offset': offset,
            'limit': limit,
            'total_records': total_records
        }
    }
    if pagination_type == pagination.TYPE_STANDARD_WITH_CALCULATION:
        pagination_dict['items'] = items[
            offset:(limit + offset if limit is not None else None)]
    if pagination_type == pagination.TYPE_NONE:
        pagination_dict['pagination'] = {
            'type': return_pagination_type,
            'total_records': total_records
        }
    return pagination_dict