"""Real storage/cache behavior; runnable with stdlib unittest and no API keys."""
import asyncio
import json
from pathlib import Path
import tempfile
import unittest
from unittest.mock import patch

from src.services.cache_service import CacheService
from src.services.metrics_service import MetricsService


class RuntimeRegressionTests(unittest.TestCase):
    def setUp(self):
        self.tmp = tempfile.TemporaryDirectory()
        self.addCleanup(self.tmp.cleanup)
        self.path = Path(self.tmp.name) / "metrics.json"
        self.metrics = MetricsService(self.path)

    def test_failed_write_retains_counts_for_retry(self):
        self.metrics.incr("agent_requests", 3)
        with patch("src.services.metrics_service.os.replace", side_effect=OSError("disk unavailable")):
            asyncio.run(self.metrics.flush())
        self.assertEqual(self.metrics.snapshot()["agent_requests"], 3)
        asyncio.run(self.metrics.flush())
        self.assertEqual(json.loads(self.path.read_text())["agent_requests"], 3)
        asyncio.run(self.metrics.flush())
        self.assertEqual(self.metrics.snapshot()["agent_requests"], 3)

    def test_invalid_json_shapes_recover_and_flush(self):
        for raw in ('[]', 'null', '{"agent_requests": {}, "intents": 1, "errors":{"x":"bad"}}'):
            self.path.write_text(raw)
            self.metrics.incr("agent_requests")
            self.metrics.incr_bucket("intents", "hours")
            asyncio.run(self.metrics.flush())
            state = self.metrics.snapshot()
            self.assertEqual(state["agent_requests"], 1)
            self.assertEqual(state["intents"], {"hours": 1})

    def test_missing_file_defaults_do_not_share_nested_counters(self):
        self.path.unlink()
        self.metrics.incr_bucket("intents", "hours")
        self.assertEqual(self.metrics.snapshot()["intents"], {"hours": 1})
        self.assertEqual(self.metrics.snapshot()["intents"], {"hours": 1})

    def test_zero_recent_queries_returns_empty(self):
        self.metrics.log_query("library hours")
        self.assertEqual(self.metrics.recent_queries(0), [])

    def test_cache_enforces_bound_immediately(self):
        cache = CacheService(max_size=2)
        for i in range(10):
            cache.set(str(i), i)
            self.assertLessEqual(len(cache._cache), 2)

    def test_cache_expires_values(self):
        cache = CacheService()
        cache.set("expired", "value", ttl=-1)
        self.assertIsNone(cache.get("expired"))
        cache.set("live", "value", ttl=30)
        self.assertEqual(cache.get("live"), "value")


if __name__ == "__main__":
    unittest.main()