cache.py

"""
cache.py — In-memory TTL cache keyed by (repo_url, day-string).

Same repo queried within 24h returns the cached result. Skips:
  - GitHub API call
  - Gemini API call (~$0.0001 saved)
  - GPU function invocation (saves Zero-GPU quota)
  - PR body generation

Storage: small dict in process memory. Sufficient for Spaces traffic
(small cardinality). Cleared on container restart.

For production scale: swap to redis with a TTL key.
"""
from __future__ import annotations

import time
from typing import Any

_TTL_SECONDS = 24 * 3600
_cache: dict[str, tuple[float, Any]] = {}


def _key(repo_url: str) -> str:
    return repo_url.strip().lower().rstrip("/")


def get(repo_url: str) -> Any | None:
    entry = _cache.get(_key(repo_url))
    if entry is None:
        return None
    ts, value = entry
    if time.time() - ts > _TTL_SECONDS:
        _cache.pop(_key(repo_url), None)
        return None
    return value


def put(repo_url: str, value: Any) -> None:
    _cache[_key(repo_url)] = (time.time(), value)


def size() -> int:
    return len(_cache)