"""User based helpers methods."""

from contextvars import ContextVar

from fastapi import Request

from moneyhub.constants.constants import APPLICATION_PROFILE_TYPE
from moneyhub.constants.constants import DEFAULT_USER_ID
from moneyhub.constants.constants import DEFAULT_USER_TYPE
from moneyhub.constants.constants import IDENTITY_HEADER
from moneyhub.constants.constants import USER_HEADER_DELIMITER
from moneyhub.constants.constants import USER_HEADER_LENGTH
from moneyhub.constants.constants import USER_HEADER_NAME

request_header = ContextVar('request_header', default=None)


def get_user_details_from_headers(request: Request) -> dict:
    """Parse user information in the headers.

    Args:
        request (Request): Request object
    Returns:
        dict: dict of user id and user type
    """
    orchard_identity_id = request.headers.get(IDENTITY_HEADER, None)
    grass_user_details = request.headers.get(USER_HEADER_NAME, None)

    user_type = DEFAULT_USER_TYPE
    user_id = DEFAULT_USER_ID
    if orchard_identity_id:
        user_type = APPLICATION_PROFILE_TYPE
        user_id = orchard_identity_id
    elif grass_user_details:
        user_type, user_id = get_user_details_from_string(grass_user_details)

    return {'type': user_type, 'id': user_id}


def get_user_details_from_string(grass_user_details: str) -> tuple:
    """Parse the pattern 'user_type:user_id' into a tuple.

    Args:
        grass_user_details (str): header parameter having user_type and user_id
    Returns:
        tuple: tuple of user id and user type
    """
    user_type = DEFAULT_USER_TYPE
    user_id = DEFAULT_USER_ID
    if grass_user_details:
        header_pieces = grass_user_details.split(USER_HEADER_DELIMITER)
        if len(header_pieces) == USER_HEADER_LENGTH:
            user_id = header_pieces.pop() or user_id
            user_type = header_pieces.pop() or user_type
    return user_type, user_id


def get_user_id() -> str:
    """Return application level user id."""
    if request_header and (user := request_header.get()):
        return user['id']
    return DEFAULT_USER_ID