"""Tests for NCS metrics module."""
import sys
import os
import asyncio

sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "services", "node-capabilities"))

from metrics import (
    record_latency, get_latency_stats, get_cpu_load, get_mem_pressure,
    build_node_load, build_runtime_load, _latency_buffer,
)


def setup_function():
    _latency_buffer.clear()


def test_record_and_get_latency():
    record_latency("ollama", "llm", 500)
    record_latency("ollama", "llm", 300)
    record_latency("ollama", "llm", 700)
    stats = get_latency_stats("ollama", "llm")
    assert stats["samples"] == 3
    assert stats["p50_ms"] == 500
    assert stats["p95_ms"] == 700


def test_empty_latency_stats():
    stats = get_latency_stats("nonexistent", "llm")
    assert stats["p50_ms"] is None
    assert stats["samples"] == 0


def test_cpu_load_returns_float_or_none():
    result = get_cpu_load()
    assert result is None or isinstance(result, float)


def test_mem_pressure_returns_valid_or_none():
    result = get_mem_pressure()
    assert result is None or result in ("low", "medium", "high", "critical")


def test_build_node_load_defaults():
    result = asyncio.run(build_node_load(worker_metrics={
        "inflight_jobs": 0, "concurrency_limit": 2, "queue_depth": 0,
    }))
    assert result["inflight_jobs"] == 0
    assert result["estimated_wait_ms"] == 0
    assert result["concurrency_limit"] == 2
    assert "ts" in result


def test_build_node_load_wait_when_busy():
    record_latency("ollama", "llm", 1000)
    result = asyncio.run(build_node_load(worker_metrics={
        "inflight_jobs": 5, "concurrency_limit": 2, "queue_depth": 0,
    }))
    assert result["estimated_wait_ms"] == 4 * 1000


def test_build_runtime_load():
    runtimes = {"ollama": {"status": "ok"}, "swapper": {"status": "error: timeout"}}
    result = asyncio.run(build_runtime_load(runtimes))
    assert len(result) == 2
    ollama_rl = next(r for r in result if r["runtime"] == "ollama")
    assert ollama_rl["healthy"] is True
    swapper_rl = next(r for r in result if r["runtime"] == "swapper")
    assert swapper_rl["healthy"] is False