"""Rate limiting: per agent or per tool; log advisory or reject if exceeded.

In ADVISORY mode, rate limit violations are logged as advisories
but the action proceeds.  Growth requires freedom to push limits.
"""

import time
from collections import defaultdict

from fusionagi._logger import logger
from fusionagi.schemas.audit import GovernanceMode


class RateLimiter:
    """Simple in-memory rate limiter: max N calls per window_seconds per key.

    In ADVISORY mode (default), exceeded limits are logged but not enforced.
    """

    def __init__(
        self,
        max_calls: int = 60,
        window_seconds: float = 60.0,
        mode: GovernanceMode = GovernanceMode.ADVISORY,
    ) -> None:
        self._max_calls = max_calls
        self._window = window_seconds
        self._calls: dict[str, list[float]] = defaultdict(list)
        self._mode = mode

    def allow(self, key: str) -> tuple[bool, str]:
        """Record a call for key; return (True, "") or (False/True, reason)."""
        now = time.monotonic()
        cutoff = now - self._window
        self._calls[key] = [t for t in self._calls[key] if t > cutoff]
        if len(self._calls[key]) >= self._max_calls:
            reason = f"Rate limit exceeded for {key}"
            if self._mode == GovernanceMode.ADVISORY:
                logger.info(
                    "RateLimiter advisory: limit exceeded (proceeding)",
                    extra={"key": key, "reason": reason, "mode": "advisory"},
                )
                self._calls[key].append(now)
                return True, f"Advisory: {reason}"
            logger.info("Rate limiter rejected", extra={"key": key, "reason": reason})
            return False, reason
        self._calls[key].append(now)
        return True, ""

    def reset(self, key: str | None = None) -> None:
        """Reset counts for key or all."""
        if key is None:
            self._calls.clear()
        else:
            self._calls.pop(key, None)