class ImportReport:
    def __init__(self):
        self.rows_seen = 0
        self.valid: List[dict] = []
        self.invalid: List[dict] = []
        self.duplicates: List[dict] = []
        self.suppressed: List[dict] = []
        self.bounced: List[dict] = []
        self.errors: List[str] = []

    def summary(self) -> dict:
        return {
            "total_imported": self.rows_seen,
            "valid_recipients": len(self.valid),
            "invalid_recipients": len(self.invalid),
            "duplicate_recipients": len(self.duplicates),
            "suppressed_recipients": len(self.suppressed),
            "bounced_recipients": len(self.bounced),
            "errors": self.errors,
        }


def is_valid_email(addr: str) -> bool:
    if not addr or len(addr) > 320:
        return False
    try:
        v = validate_email(addr, check_deliverability=False)
        return True
    except EmailNotValidError:
        return EMAIL_RE.match(addr) is not None


def parse_txt(content: str) -> List[str]:
    """One email per line (optionally 'email, First, Last' comma-separated)."""