"""
Tests for the status worker background task and aggregated stats endpoint.
"""

from datetime import datetime
from unittest import mock

import pytest


class TestCollectAllStatus:
    """Tests for collect_all_status function."""

    @pytest.mark.asyncio
    async def test_collects_all_stats_and_iso_timestamp(self):
        """Should collect every status type and include a parseable ISO timestamp."""
        from controller.lib.status_worker import collect_all_status

        status = await collect_all_status()

        for key in (
            "cpu_stats", "memory_stats", "load_stats", "drives_stats",
            "nic_bandwidth_stats", "power_stats", "smart_stats", "last_status",
        ):
            assert key in status
        datetime.fromisoformat(status["last_status"])

    @pytest.mark.asyncio
    async def test_smart_stats_passed_through(self):
        """The smart_stats kwarg should land in the cached payload verbatim."""
        from controller.lib.status_worker import collect_all_status

        smart = {"drives": [{"device": "sda", "temperature": 52}],
                 "high_temperature": 55, "critical_temperature": 65}
        status = await collect_all_status(smart_stats=smart)
        assert status["smart_stats"] is smart

    @pytest.mark.asyncio
    async def test_smart_stats_defaults_to_none(self):
        """Without the kwarg, smart_stats is None (worker fills it in)."""
        from controller.lib.status_worker import collect_all_status

        status = await collect_all_status()
        assert status["smart_stats"] is None

    @pytest.mark.asyncio
    @pytest.mark.parametrize("collector,result_key,failure_value", [
        ("get_cpu_status", "cpu_stats", None),
        ("get_memory_status", "memory_stats", None),
        ("get_drive_status", "drives_stats", []),
        ("get_network_status", "nic_bandwidth_stats", {}),
    ])
    async def test_individual_collector_failure(self, collector, result_key, failure_value):
        """A single collector raising should leave the failed key at its fallback value
        and let the other collectors still populate the result."""
        from controller.lib.status_worker import collect_all_status

        with mock.patch(
            f"controller.lib.status_worker.{collector}",
            side_effect=Exception(f"{collector} error"),
        ):
            status = await collect_all_status()
        assert status[result_key] == failure_value
        # At least one other collector should still have produced real data.
        other_keys = [k for k in ("cpu_stats", "memory_stats") if k != result_key]
        assert any(status[k] is not None for k in other_keys)


class TestRefreshSmartStats:
    """SMART must be collected on a slow cadence, not every status cycle."""

    def _fake_app(self):
        app = mock.Mock()
        app.state = mock.Mock(spec=[])  # no smart_cache / smart_last_collected yet
        return app

    @pytest.mark.asyncio
    async def test_collects_on_first_call(self):
        from controller.lib.status_worker import refresh_smart_stats

        sentinel = {"drives": [], "high_temperature": 55, "critical_temperature": 65}
        with mock.patch("controller.lib.status_worker.build_smart_stats",
                        return_value=sentinel) as build:
            app = self._fake_app()
            now = datetime(2026, 6, 3, 12, 0, 0)
            result = await refresh_smart_stats(app, now)

        build.assert_called_once()
        assert result is sentinel
        assert app.state.smart_cache is sentinel
        assert app.state.smart_last_collected == now

    @pytest.mark.asyncio
    async def test_reuses_cache_before_interval(self):
        """A second call a few seconds later must NOT re-read SMART."""
        from controller.lib.status_worker import refresh_smart_stats

        with mock.patch("controller.lib.status_worker.build_smart_stats",
                        side_effect=[{"n": 1}, {"n": 2}]) as build:
            app = self._fake_app()
            t0 = datetime(2026, 6, 3, 12, 0, 0)
            first = await refresh_smart_stats(app, t0)
            # 5s later — well within the 60s window.
            second = await refresh_smart_stats(app, datetime(2026, 6, 3, 12, 0, 5))

        assert build.call_count == 1
        assert first == {"n": 1}
        assert second == {"n": 1}

    @pytest.mark.asyncio
    async def test_refreshes_after_interval(self):
        """After >= 60s, SMART is re-read and the prior result is passed in."""
        from controller.lib.status_worker import refresh_smart_stats

        with mock.patch("controller.lib.status_worker.build_smart_stats",
                        side_effect=[{"n": 1}, {"n": 2}]) as build:
            app = self._fake_app()
            t0 = datetime(2026, 6, 3, 12, 0, 0)
            await refresh_smart_stats(app, t0)
            result = await refresh_smart_stats(app, datetime(2026, 6, 3, 12, 1, 0))

        assert build.call_count == 2
        # The prior cache is handed to build_smart_stats for spin-down reuse.
        assert build.call_args_list[1].args[0] == {"n": 1}
        assert result == {"n": 2}


class TestGetAdaptiveSleep:
    """Tests for adaptive sleep calculation."""

    def test_returns_base_sleep_when_load_is_low(self):
        """Should return base sleep when load is below CPU count."""
        from controller.lib.status_worker import get_adaptive_sleep

        with mock.patch("multiprocessing.cpu_count", return_value=4):
            load_stats = {"minute_1": "0.5"}
            sleep = get_adaptive_sleep(load_stats, base_sleep=5.0)
            assert sleep == 5.0

    def test_returns_base_sleep_when_load_equals_cpu_count(self):
        """Should return base sleep when load equals CPU count."""
        from controller.lib.status_worker import get_adaptive_sleep

        with mock.patch("multiprocessing.cpu_count", return_value=4):
            load_stats = {"minute_1": "4.0"}
            sleep = get_adaptive_sleep(load_stats, base_sleep=5.0)
            assert sleep == 5.0

    def test_increases_sleep_when_load_exceeds_cpu_count(self):
        """Should increase sleep when load exceeds CPU count."""
        from controller.lib.status_worker import get_adaptive_sleep

        with mock.patch("multiprocessing.cpu_count", return_value=4):
            load_stats = {"minute_1": "8.0"}  # 2x CPU count
            sleep = get_adaptive_sleep(load_stats, base_sleep=5.0)
            # Expected: (5.0 * 8.0) / 4 = 10.0
            assert sleep == 10.0

    def test_handles_none_load_stats(self):
        """Should return base sleep when load_stats is None."""
        from controller.lib.status_worker import get_adaptive_sleep

        sleep = get_adaptive_sleep(None, base_sleep=5.0)
        assert sleep == 5.0

    def test_handles_empty_load_stats(self):
        """Should return base sleep when load_stats is empty dict."""
        from controller.lib.status_worker import get_adaptive_sleep

        sleep = get_adaptive_sleep({}, base_sleep=5.0)
        assert sleep == 5.0

    def test_handles_invalid_load_value(self):
        """Should return base sleep when load value is invalid."""
        from controller.lib.status_worker import get_adaptive_sleep

        load_stats = {"minute_1": "invalid"}
        sleep = get_adaptive_sleep(load_stats, base_sleep=5.0)
        assert sleep == 5.0

    def test_handles_missing_minute_1_key(self):
        """Should return base sleep when minute_1 key is missing."""
        from controller.lib.status_worker import get_adaptive_sleep

        load_stats = {"minute_5": "2.0"}
        sleep = get_adaptive_sleep(load_stats, base_sleep=5.0)
        assert sleep == 5.0


class TestAggregatedStatsEndpoint:
    """Tests for the /api/stats aggregated endpoint."""

    def test_aggregated_stats_payload(self, test_client):
        """Endpoint should return 200 with every status key and the expected sub-shapes."""
        response = test_client.get("/api/stats")
        assert response.status_code == 200
        data = response.json()

        for key in (
            "cpu_stats", "memory_stats", "load_stats", "drives_stats",
            "nic_bandwidth_stats", "power_stats", "smart_stats", "last_status",
        ):
            assert key in data
        # last_status is an ISO timestamp.
        datetime.fromisoformat(data["last_status"])
        # SMART carries its thresholds for the frontend warning.
        for field in ("drives", "high_temperature", "critical_temperature"):
            assert field in data["smart_stats"]
        # Sub-field shape spot-checks.
        for field in ("percent", "cores"):
            assert field in data["cpu_stats"]
        for field in ("total", "used", "free"):
            assert field in data["memory_stats"]
        for field in ("minute_1", "minute_5", "minute_15"):
            assert field in data["load_stats"]
        assert isinstance(data["drives_stats"], list)
        assert isinstance(data["nic_bandwidth_stats"], dict)

    def test_aggregated_stats_trailing_slash(self, test_client):
        """Aggregated stats should work with trailing slash."""
        response = test_client.get("/api/stats/")
        assert response.status_code == 200