from __future__ import annotations

import asyncio
import time


class MatrixRateLimiter:
    def __init__(self, max_requests: int = 30, per_seconds: float = 1.0):
        self._tokens = float(max_requests)
        self._max = max_requests
        self._rate = per_seconds
        self._last_refill = time.monotonic()
        self._lock = asyncio.Lock()

    async def acquire(self) -> None:
        async with self._lock:
            now = time.monotonic()
            elapsed = now - self._last_refill
            refill = elapsed / self._rate * self._max
            self._tokens = min(self._max, self._tokens + refill)
            self._last_refill = now
            if self._tokens < 1:
                wait = self._rate / self._max
                await asyncio.sleep(wait)
                self._tokens = 1
            self._tokens -= 1