from __future__ import annotations

from collections import OrderedDict


class EventDeduplicator:
    def __init__(self, max_size: int = 10000):
        self._seen: OrderedDict[str, None] = OrderedDict()
        self._max_size = max_size

    def is_duplicate(self, event_id: str) -> bool:
        if event_id in self._seen:
            self._seen.move_to_end(event_id)
            return True

        self._seen[event_id] = None
        if len(self._seen) > self._max_size:
            self._seen.popitem(last=False)
        return False

    def clear(self) -> None:
        self._seen.clear()

    def __len__(self) -> int:
        return len(self._seen)