import re

TEMPLATE_NAME_PATTERN = re.compile(r"^[A-Z0-9_]{3,40}$")
DLT_TEMPLATE_ID_PATTERN = re.compile(r"^\d{12,25}$")
VARIABLE_TOKEN = "{#var#}"


def normalize_template_name(value: str) -> str:
    return value.strip().upper().replace(" ", "_")


def validate_template_name(value: str) -> str:
    name = normalize_template_name(value)
    if not TEMPLATE_NAME_PATTERN.match(name):
        raise ValueError("Template name must be 3–40 uppercase letters, numbers, or underscores")
    return name


def validate_template_text(value: str) -> str:
    text = value.strip()
    if len(text) < 10:
        raise ValueError("Template must be at least 10 characters")
    if len(text) > 1000:
        raise ValueError("Template must be 1000 characters or fewer")
    return text


def validate_dlt_template_id(value: str) -> str:
    template_id = value.strip()
    if not DLT_TEMPLATE_ID_PATTERN.match(template_id):
        raise ValueError("DLT Template ID must be 12–25 digits")
    return template_id