import pgpy
from email_validator import validate_email


def import_key_from_attachment(file_path: str) -> (str, str, str):
    """Import a PGP public key from an attachment.

    :param file_path: the path to the attachment
    :return: a tuple with the public key, the email address, and a displayname
    """
    try:
        key = pgpy.PGPKey.from_file(file_path)[0]
    except ValueError:
        return "", "", ""
    except AttributeError:
        return "", "", ""
    except pgpy.errors.PGPError:
        return "", "", ""
    ascii_key = str(key)
    keyparts = []
    for line in ascii_key.splitlines():
        if line != "" and not ": " in line and not line.startswith("=") and not line.startswith("-----"):
            keyparts.append(line)
    uid = key.get_uid("").userid
    email = validate_email(uid, allow_display_name=True).ascii_email
    display_name = validate_email(uid, allow_display_name=True).display_name
    return "".join(keyparts), email, display_name