"""Tests for the metrics collector."""

from fusionagi.api.metrics import MetricsCollector


class TestMetricsCollector:
    def test_counter(self) -> None:
        m = MetricsCollector()
        m.inc("requests")
        m.inc("requests")
        snap = m.snapshot()
        assert snap["counters"]["requests"] == 2

    def test_counter_with_labels(self) -> None:
        m = MetricsCollector()
        m.inc("http_requests", labels={"method": "GET"})
        m.inc("http_requests", labels={"method": "POST"})
        snap = m.snapshot()
        assert snap["counters"]["http_requests{method=GET}"] == 1
        assert snap["counters"]["http_requests{method=POST}"] == 1

    def test_histogram(self) -> None:
        m = MetricsCollector()
        for v in [0.1, 0.2, 0.3, 0.4, 0.5]:
            m.observe("latency", v)
        snap = m.snapshot()
        assert snap["histograms"]["latency"]["count"] == 5
        assert 0.2 < snap["histograms"]["latency"]["mean"] < 0.4

    def test_gauge(self) -> None:
        m = MetricsCollector()
        m.set_gauge("active_sessions", 5.0)
        snap = m.snapshot()
        assert snap["gauges"]["active_sessions"] == 5.0

    def test_uptime(self) -> None:
        m = MetricsCollector()
        snap = m.snapshot()
        assert snap["uptime_seconds"] >= 0