const test = require('node:test');
const assert = require('node:assert/strict');
const { initialState, evaluate } = require('../src/alertState');

const opts = { alertThreshold: 3, realertIntervalMs: 30 * 60 * 1000 };

test('連続失敗がしきい値未満なら通知しない', () => {
  let state = initialState();
  let r = evaluate(state, false, 1000, opts);
  assert.equal(r.action, 'none');
  assert.equal(r.newState.consecutiveFailures, 1);

  r = evaluate(r.newState, false, 2000, opts);
  assert.equal(r.action, 'none');
  assert.equal(r.newState.consecutiveFailures, 2);
});

test('しきい値到達で最初のアラートを1回だけ出す', () => {
  let state = initialState();
  state = evaluate(state, false, 1000, opts).newState;
  state = evaluate(state, false, 2000, opts).newState;
  const r = evaluate(state, false, 3000, opts);
  assert.equal(r.action, 'alert-down');
  assert.equal(r.newState.alerted, true);
  assert.equal(r.newState.lastAlertAt, 3000);
});

test('アラート後、再通知間隔内は沈黙する', () => {
  let state = { consecutiveFailures: 3, alerted: true, lastAlertAt: 1000 };
  const r = evaluate(state, false, 1000 + 10 * 60 * 1000, opts); // 10分後
  assert.equal(r.action, 'none');
});

test('再通知間隔を過ぎたら再度アラートする', () => {
  let state = { consecutiveFailures: 3, alerted: true, lastAlertAt: 1000 };
  const r = evaluate(state, false, 1000 + 31 * 60 * 1000, opts); // 31分後
  assert.equal(r.action, 'alert-still-down');
  assert.equal(r.newState.lastAlertAt, 1000 + 31 * 60 * 1000);
});

test('アラート中に復旧したら復旧通知を1回出し状態をリセットする', () => {
  const state = { consecutiveFailures: 5, alerted: true, lastAlertAt: 1000 };
  const r = evaluate(state, true, 5000, opts);
  assert.equal(r.action, 'alert-recovered');
  assert.deepEqual(r.newState, initialState());
});

test('アラート未発生のまま復旧した場合は通知しない', () => {
  const state = { consecutiveFailures: 1, alerted: false, lastAlertAt: null };
  const r = evaluate(state, true, 5000, opts);
  assert.equal(r.action, 'none');
  assert.deepEqual(r.newState, initialState());
});