"""
Tests for PipelineMetricsSensor.
"""

from engine.sensors.pipeline_metrics import PipelineMetricsSensor


class MockPipeline:
    """Mock pipeline for testing."""

    def __init__(self, metrics=None):
        self._metrics = metrics or {}

    def get_metrics_summary(self):
        return self._metrics


class TestPipelineMetricsSensor:
    """Tests for PipelineMetricsSensor."""

    def test_basic_init(self):
        """Sensor initializes with defaults."""
        sensor = PipelineMetricsSensor()
        assert sensor.name == "pipeline"
        assert sensor.available is False

    def test_init_with_pipeline(self):
        """Sensor initializes with pipeline."""
        mock = MockPipeline()
        sensor = PipelineMetricsSensor(mock)
        assert sensor.available is True

    def test_set_pipeline(self):
        """set_pipeline() updates pipeline."""
        sensor = PipelineMetricsSensor()
        assert sensor.available is False
        sensor.set_pipeline(MockPipeline())
        assert sensor.available is True

    def test_read_no_pipeline(self):
        """read() returns None when no pipeline."""
        sensor = PipelineMetricsSensor()
        assert sensor.read() is None

    def test_read_with_metrics(self):
        """read() returns sensor value with metrics."""
        mock = MockPipeline(
            {
                "total_ms": 18.5,
                "fps": 54.0,
                "avg_ms": 18.5,
                "min_ms": 15.0,
                "max_ms": 22.0,
                "stages": {"render": {"avg_ms": 12.0}, "noise": {"avg_ms": 3.0}},
            }
        )
        sensor = PipelineMetricsSensor(mock)
        val = sensor.read()
        assert val is not None
        assert val.sensor_name == "pipeline"
        assert val.value == 18.5

    def test_read_with_error(self):
        """read() returns None when metrics have error."""
        mock = MockPipeline({"error": "No metrics collected"})
        sensor = PipelineMetricsSensor(mock)
        assert sensor.read() is None

    def test_get_stage_timing(self):
        """get_stage_timing() returns stage timing."""
        mock = MockPipeline(
            {
                "stages": {"render": {"avg_ms": 12.0}, "noise": {"avg_ms": 3.0}},
            }
        )
        sensor = PipelineMetricsSensor(mock)
        assert sensor.get_stage_timing("render") == 12.0
        assert sensor.get_stage_timing("noise") == 3.0
        assert sensor.get_stage_timing("nonexistent") == 0.0

    def test_get_stage_timing_no_pipeline(self):
        """get_stage_timing() returns 0 when no pipeline."""
        sensor = PipelineMetricsSensor()
        assert sensor.get_stage_timing("test") == 0.0

    def test_get_all_timings(self):
        """get_all_timings() returns all stage timings."""
        mock = MockPipeline(
            {
                "stages": {"render": {"avg_ms": 12.0}, "noise": {"avg_ms": 3.0}},
            }
        )
        sensor = PipelineMetricsSensor(mock)
        timings = sensor.get_all_timings()
        assert timings == {"render": {"avg_ms": 12.0}, "noise": {"avg_ms": 3.0}}

    def test_get_frame_history(self):
        """get_frame_history() returns frame times."""
        MockPipeline()

        class MockPipelineWithFrames:
            def get_frame_times(self):
                return [1.0, 2.0, 3.0]

        sensor = PipelineMetricsSensor(MockPipelineWithFrames())
        history = sensor.get_frame_history()
        assert history == [1.0, 2.0, 3.0]

    def test_start_stop(self):
        """start() and stop() work."""
        sensor = PipelineMetricsSensor()
        assert sensor.start() is True
        sensor.stop()  # Should not raise