def normalize_target_input(raw: str) -> str:
    if not raw:
        return ""
    cleaned = raw.strip()
    if ":" in cleaned:
        prefix, rest = cleaned.split(":", 1)
        return f"{prefix.lower().strip()}:{rest.strip()}"
    return cleaned


def detect_target_kind(raw: str, channel_chat_types: list[str] | None = None) -> str:
    trimmed = raw.strip()

    if trimmed.startswith("@") or trimmed.lower().startswith("user:"):
        return "user"
    if trimmed.startswith("#") or trimmed.lower().startswith("channel:"):
        return "group"
    if trimmed.lower().startswith("thread:"):
        return "channel"

    if channel_chat_types:
        if "direct" in channel_chat_types and "group" not in channel_chat_types:
            return "user"

    return "group"


def looks_like_target_id(raw: str) -> bool:
    trimmed = raw.strip()
    core = trimmed
    for prefix in ("user:", "channel:", "group:", "thread:", "@", "#"):
        if core.lower().startswith(prefix):
            core = core[len(prefix) :].strip()
            break

    if not core:
        return False

    if core.isdigit():
        return True

    if any("\u4e00" <= c <= "\u9fff" for c in core):
        return False
    if " " in core:
        return False

    if "-" in core and len(core) > 20:
        return True

    return False