"""
cache.py — import this before anything else in a test file to enable
file-based caching of fetch_json and fetch_soup calls.

Cache is stored in tests/cache/ keyed by a hash of the URL + params.
Delete the cache directory to bust it.
"""

import hashlib
import json
import pickle
from pathlib import Path

CACHE_DIR = Path(__file__).parent / "cache"
CACHE_DIR.mkdir(exist_ok=True)


def _key(url: str, params: dict[str,str] | None) -> str:
    raw = json.dumps({"url": url, "params": params or {}}, sort_keys=True)
    return hashlib.sha256(raw.encode()).hexdigest()


def _patch():
    import adapters.api as api_mod
    import adapters.ssr as ssr_mod

    _orig_fetch_json = api_mod.fetch_json
    _orig_fetch_soup = ssr_mod.fetch_soup

    def cached_fetch_json(url, *, params: dict[str,str]|None=None, headers=None):
        path = CACHE_DIR / (_key(url, params) + ".json")
        if path.exists():
            print(f"[cache hit] {url}")
            return json.loads(path.read_text())
        result = _orig_fetch_json(url, params=params, headers=headers)
        path.write_text(json.dumps(result))
        return result

    def cached_fetch_soup(url, *, params=None):
        path = CACHE_DIR / (_key(url, params) + ".pickle")
        if path.exists():
            print(f"[cache hit] {url}")
            return pickle.loads(path.read_bytes())
        result = _orig_fetch_soup(url, params=params)
        path.write_bytes(pickle.dumps(result))
        return result

    api_mod.fetch_json = cached_fetch_json
    ssr_mod.fetch_soup = cached_fetch_soup
    print("[cache] fetch_json and fetch_soup patched")


_patch()