import http from 'k6/http';
import { check, sleep } from 'k6';
import { Rate, Trend } from 'k6/metrics';

const BASE_URL = __ENV.BASE_URL;
const SCENARIO = __ENV.SCENARIO || 'mixed';
const MODE = __ENV.MODE || 'duration';
const OUTLOOK_PAYLOAD = __ENV.OUTLOOK_PAYLOAD || '../payloads/outlook.json';
const ACHIEVEMENT_PAYLOAD = __ENV.ACHIEVEMENT_PAYLOAD || '../payloads/achievement.json';
const REQUEST_TIMEOUT = __ENV.REQUEST_TIMEOUT || '120s';

const outlookPayload = open(OUTLOOK_PAYLOAD);
const achievementPayload = open(ACHIEVEMENT_PAYLOAD);

const businessSuccess = new Rate('business_success');
const outlookDuration = new Trend('outlook_sync_duration');
const achievementDuration = new Trend('achievement_sync_duration');

function scenarioOptions() {
  if (MODE === 'burst') {
    return {
      scenarios: {
        burst_once: {
          executor: 'per-vu-iterations',
          vus: Number(__ENV.VUS || 20),
          iterations: Number(__ENV.ITERATIONS_PER_VU || 1),
          maxDuration: __ENV.MAX_DURATION || '2m',
        },
      },
    };
  }

  return {
    vus: Number(__ENV.VUS || 20),
    duration: __ENV.DURATION || '3m',
  };
}

export const options = {
  ...scenarioOptions(),
  thresholds: {
    http_req_failed: ['rate==0'],
    business_success: ['rate==1'],
  },
};

function requireBaseUrl() {
  if (!BASE_URL) {
    throw new Error('BASE_URL is required, for example: BASE_URL=https://test-host k6 run loadtest/k6/report-sync.js');
  }
}

function postSync(path, payload, apiName) {
  const response = http.post(`${BASE_URL}${path}`, payload, {
    headers: {
      'Content-Type': 'application/json',
      ...( __ENV.TOKEN ? { Authorization: `Bearer ${__ENV.TOKEN}` } : {} ),
    },
    tags: { api: apiName },
    timeout: REQUEST_TIMEOUT,
  });

  const ok = check(response, {
    [`${apiName} status is 200`]: (res) => res.status === 200,
    [`${apiName} has downloadUrl`]: (res) => {
      try {
        return Boolean(res.json('data.downloadUrl'));
      } catch (error) {
        return false;
      }
    },
  });

  businessSuccess.add(ok, { api: apiName });

  if (apiName === 'outlook_sync') {
    outlookDuration.add(response.timings.duration);
  }

  if (apiName === 'achievement_sync') {
    achievementDuration.add(response.timings.duration);
  }
}

export default function () {
  requireBaseUrl();

  if (SCENARIO === 'outlook') {
    postSync('/api/exam-sprint/outlook-reports/sync', outlookPayload, 'outlook_sync');
  } else if (SCENARIO === 'achievement') {
    postSync('/api/exam-sprint/achievement-reports/sync', achievementPayload, 'achievement_sync');
  } else {
    if ((__VU + __ITER) % 2 === 0) {
      postSync('/api/exam-sprint/outlook-reports/sync', outlookPayload, 'outlook_sync');
    } else {
      postSync('/api/exam-sprint/achievement-reports/sync', achievementPayload, 'achievement_sync');
    }
  }

  sleep(Number(__ENV.SLEEP_SECONDS || 0.2));
}