import test from 'brittle'
import { MetricStore } from '../server/services/store.js'
import { AnomalyEngine } from '../server/services/anomaly.js'
import { stats, zScore, thresholdsFromStats, seriesFromStore } from '../server/services/zscore.js'

test('stats and zScore', (t) => {
  const s = stats([10, 12, 11, 13, 10])
  t.ok(s.n === 5)
  t.ok(Math.abs(s.mean - 11.2) < 0.01)
  t.ok(s.stdev > 0)
  t.ok(Math.abs(zScore(11.2, s.mean, s.stdev)) < 0.01)
  t.ok(zScore(20, s.mean, s.stdev) > 2)
})

test('thresholdsFromStats greater-than', (t) => {
  const thr = thresholdsFromStats({ mean: 10, stdev: 2 }, '>', { warnZ: 2, critZ: 3 })
  t.is(thr.warn, 14)
  t.is(thr.crit, 16)
})

test('retrainAnomaly updates thresholds from store', (t) => {
  const store = new MetricStore()
  const now = Date.now()
  for (let i = 0; i < 40; i++) {
    store.ingest([
      {
        chart: 'system.cpu',
        context: 'system.cpu',
        ts: now + i * 1000,
        values: {
          user: 20 + (i % 3),
          system: 5,
          nice: 0,
          iowait: 0,
          irq: 0,
          softirq: 0,
          idle: 70,
          steal: 0,
        },
      },
    ])
  }
  const eng = new AnomalyEngine({ cpuCount: 2 })
  const res = eng.retrain(store, { minPoints: 20, warnZ: 2, critZ: 3 })
  t.ok(res.ok)
  t.ok(res.updated.length >= 1)
  const cpu = eng.configs.get('cpu_user_high')
  t.ok(cpu.warn > 20)
  t.ok(cpu.crit >= cpu.warn)
  t.ok(seriesFromStore(store, 'system.cpu', 'user').length >= 20)
})