import assert from 'node:assert/strict';
import test from 'node:test';
import {
  clearDataSourceTelemetry,
  getDataSourceTelemetry,
  observeDataSource,
  recordDataSourceOutcome,
} from './source-telemetry.js';

test('reports unobserved sources without treating them as failures', () => {
  clearDataSourceTelemetry();
  const report = getDataSourceTelemetry(new Date('2026-08-07T08:00:00Z'));
  assert.ok(report.sources.every(source => source.state === 'unobserved'));
  assert.ok(report.sources.every(source => source.failureRate === null));
});

test('publishes rolling outcomes and last success/failure timestamps', () => {
  clearDataSourceTelemetry();
  recordDataSourceOutcome('oneOsMileage', true, 1_000);
  recordDataSourceOutcome('oneOsMileage', false, 2_000);
  const source = getDataSourceTelemetry().sources.find(item => item.source === 'oneOsMileage');
  assert.deepEqual(source && {
    state: source.state,
    attempts: source.attempts,
    failures: source.failures,
    failureRate: source.failureRate,
    lastSuccessAt: source.lastSuccessAt,
    lastFailureAt: source.lastFailureAt,
  }, {
    state: 'failing',
    attempts: 2,
    failures: 1,
    failureRate: 0.5,
    lastSuccessAt: '1970-01-01T00:00:01.000Z',
    lastFailureAt: '1970-01-01T00:00:02.000Z',
  });
});

test('observes final operation outcomes without retaining error details', async () => {
  clearDataSourceTelemetry();
  await assert.rejects(observeDataSource('hydrogenDatabase', async () => {
    throw new Error('sensitive connection detail');
  }));
  const serialized = JSON.stringify(getDataSourceTelemetry());
  assert.equal(serialized.includes('sensitive connection detail'), false);
});

test('keeps only the latest 100 outcomes', () => {
  clearDataSourceTelemetry();
  recordDataSourceOutcome('etcDatabase', false, 1);
  for (let index = 0; index < 100; index += 1) {
    recordDataSourceOutcome('etcDatabase', true, index + 2);
  }
  const source = getDataSourceTelemetry().sources.find(item => item.source === 'etcDatabase');
  assert.equal(source?.attempts, 100);
  assert.equal(source?.failures, 0);
  assert.equal(source?.failureRate, 0);
});