"""Unit tests for the SQLite web cache (backend.tools.webcache, #92)."""

import pytest

from backend.tools import webcache


@pytest.fixture
def cache_enabled(tmp_path, monkeypatch):
    """Enable the cache against an isolated file with a short TTL."""
    monkeypatch.setenv("OBSIGATE_WEB_CACHE_PATH", str(tmp_path / "cache.sqlite3"))
    monkeypatch.setenv("OBSIGATE_WEB_CACHE_TTL", "60")
    webcache._schema_ready = False
    yield
    webcache._schema_ready = False


class TestCacheKey:
    def test_deterministic_and_payload_sensitive(self):
        a = webcache.cache_key("search", {"q": "pizza", "page": 1})
        b = webcache.cache_key("search", {"page": 1, "q": "pizza"})
        c = webcache.cache_key("search", {"q": "pasta", "page": 1})
        d = webcache.cache_key("fetch", {"q": "pizza", "page": 1})
        assert a == b
        assert a != c
        assert a != d


class TestCacheRoundTrip:
    def test_set_get_roundtrip(self, cache_enabled):
        key = webcache.cache_key("search", {"q": "x"})
        webcache.cache_set(key, {"results": [1, 2, 3], "provider": "tavily"})
        assert webcache.cache_get(key) == {"results": [1, 2, 3], "provider": "tavily"}

    def test_miss_returns_none(self, cache_enabled):
        assert webcache.cache_get("search:unknown") is None

    def test_overwrite_updates_value(self, cache_enabled):
        key = webcache.cache_key("search", {"q": "x"})
        webcache.cache_set(key, {"v": 1})
        webcache.cache_set(key, {"v": 2})
        assert webcache.cache_get(key) == {"v": 2}

    def test_ttl_expiry(self, tmp_path, monkeypatch):
        monkeypatch.setenv("OBSIGATE_WEB_CACHE_PATH", str(tmp_path / "cache.sqlite3"))
        monkeypatch.setenv("OBSIGATE_WEB_CACHE_TTL", "0.05")
        webcache._schema_ready = False
        key = webcache.cache_key("search", {"q": "x"})
        webcache.cache_set(key, {"v": 1})
        assert webcache.cache_get(key) == {"v": 1}
        import time

        time.sleep(0.15)
        assert webcache.cache_get(key) is None

    def test_disabled_when_ttl_zero(self, cache_enabled, monkeypatch):
        monkeypatch.setenv("OBSIGATE_WEB_CACHE_TTL", "0")
        key = webcache.cache_key("search", {"q": "x"})
        webcache.cache_set(key, {"v": 1})
        assert webcache.cache_get(key) is None

    def test_purge_expired(self, cache_enabled, monkeypatch):
        key = webcache.cache_key("search", {"q": "x"})
        webcache.cache_set(key, {"v": 1})
        monkeypatch.setenv("OBSIGATE_WEB_CACHE_TTL", "0.05")
        import time

        time.sleep(0.15)
        assert webcache.purge_expired() >= 1
        assert webcache.cache_get(key) is None

    def test_corrupt_db_degrades_silently(self, tmp_path, monkeypatch):
        # A directory as cache file breaks sqlite3.connect: the cache must
        # disable itself instead of breaking the tools.
        monkeypatch.setenv("OBSIGATE_WEB_CACHE_PATH", str(tmp_path))
        monkeypatch.setenv("OBSIGATE_WEB_CACHE_TTL", "60")
        webcache._schema_ready = False
        try:
            assert webcache.cache_get("search:x") is None
            webcache.cache_set("search:x", {"v": 1})
        finally:
            webcache._schema_ready = False