from pydantic import EmailStr, TypeAdapter

_email_adapter = TypeAdapter(EmailStr)


def parse_recipient_list(raw: str) -> list[str]:
    recipients: list[str] = []
    for part in raw.split(","):
        addr = part.strip()
        if not addr:
            continue
        if any(ch in addr for ch in ("\n", "\r", "\0")):
            raise ValueError(f"Ungültige E-Mail-Adresse: {addr!r}")
        _email_adapter.validate_python(addr)
        recipients.append(addr)
    return recipients