from __future__ import annotations

import time
from collections import OrderedDict


class EventDeduplicator:
    def __init__(self, max_size: int = 10000, ttl_seconds: float = 300):
        self._seen: OrderedDict[str, float] = OrderedDict()
        self._max_size = max_size
        self._ttl = ttl_seconds

    def is_duplicate(self, event_id: str) -> bool:
        now = time.monotonic()
        while self._seen:
            oldest_id, oldest_ts = next(iter(self._seen.items()))
            if now - oldest_ts > self._ttl:
                self._seen.popitem(last=False)
            else:
                break

        if event_id in self._seen:
            self._seen.move_to_end(event_id)
            return True

        self._seen[event_id] = now
        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)