"""
Tests for utils/cache.py - file-ID deduplication cache.

Each test gets an isolated cache file via the `isolated_cache` fixture
so tests never touch data/cache.json.
"""

import pytest
import utils.cache as cache_module


@pytest.fixture(autouse=True)
def isolated_cache(tmp_path, monkeypatch):
    monkeypatch.setattr(cache_module, "CACHE_FILE", tmp_path / "cache.json")


def test_unseen_id_returns_false():
    assert cache_module.is_seen(12345) is False


def test_mark_seen_makes_id_seen():
    cache_module.mark_seen(12345)
    assert cache_module.is_seen(12345) is True


def test_multiple_ids_stored_independently():
    cache_module.mark_seen(1)
    cache_module.mark_seen(2)
    cache_module.mark_seen(3)
    assert cache_module.is_seen(1)
    assert cache_module.is_seen(2)
    assert cache_module.is_seen(3)
    assert not cache_module.is_seen(4)


def test_persists_to_disk_between_calls():
    """
    is_seen() and mark_seen() each load from disk independently.
    This verifies the persist-on-write / load-on-read contract
    (simulating what happens across separate function calls in the bot loop).
    """
    cache_module.mark_seen(999)
    assert cache_module.is_seen(999) is True


def test_missing_cache_file_handled_gracefully(tmp_path, monkeypatch):
    monkeypatch.setattr(cache_module, "CACHE_FILE", tmp_path / "nonexistent.json")
    assert cache_module.is_seen(42) is False


def test_mark_seen_is_idempotent():
    cache_module.mark_seen(7)
    cache_module.mark_seen(7)
    cache_module.mark_seen(7)
    assert cache_module.is_seen(7) is True