"""Validation of project code."""

from folding_studio.config import FOLDING_PROJECT_CODE
from folding_studio.utils.exceptions import ProjectCodeNotFound


def define_project_code_or_raise(project_code: str | None) -> str:
    """
    Args:
        project_code (str|None): Project code under which the jobs are billed.

    Return:
        The project code.
    """
    # Look into env var if None was passed
    project_code = project_code or FOLDING_PROJECT_CODE
    if project_code is None:
        msg = (
            "Project code is not set. Please either:\n"
            "set the env var FOLDING_PROJECT_CODE."
        )
        raise ProjectCodeNotFound(msg)
    return project_code