"""Sliding-window rate limiter. Redis if configured, otherwise in-process memory."""

from __future__ import annotations

import time
from collections import defaultdict, deque

from fastapi import HTTPException, status


class MemoryRateLimiter:
    def __init__(self) -> None:
        self._hits: dict[str, deque[float]] = defaultdict(deque)

    def check(self, key: str, limit: int, window_s: int, message_fr: str) -> None:
        now = time.time()
        q = self._hits[key]
        while q and q[0] < now - window_s:
            q.popleft()
        if len(q) >= limit:
            raise HTTPException(status.HTTP_429_TOO_MANY_REQUESTS, detail=message_fr)
        q.append(now)

    def count(self, key: str, window_s: int) -> int:
        now = time.time()
        q = self._hits[key]
        while q and q[0] < now - window_s:
            q.popleft()
        return len(q)


limiter = MemoryRateLimiter()

MSG_MESSAGES = "Tu as atteint la limite de messages pour l'instant. Réessaie un peu plus tard."
MSG_SANDBOX = "Limite d'exécutions Python atteinte pour cette heure."
MSG_WEB = "Limite de recherches web atteinte pour aujourd'hui."
MSG_UPLOAD = "Limite de téléversements atteinte pour aujourd'hui."