import { check, fail, sleep } from 'k6';
import http from 'k6/http';

// Parameters
const vus = __ENV.VUS || 1
const perVuIterations = parseInt(__ENV.PER_VU_ITERATIONS || 30)
const baseUrl = __ENV.BASE_URL
const username = __ENV.USERNAME
const password = __ENV.PASSWORD
const token = __ENV.TOKEN
const cluster = __ENV.CLUSTER || "local"
const resource = __ENV.RESOURCE || "management.cattle.io.setting"
const api = __ENV.API || "steve"
const paginationStyle = __ENV.PAGINATION_STYLE || "k8s"
const pageSize = parseInt(__ENV.PAGE_SIZE || 100)
const firstPageOnly = __ENV.FIRST_PAGE_ONLY === "true"
const urlSuffix = __ENV.URL_SUFFIX || ""
const pauseSeconds = parseFloat(__ENV.PAUSE_SECONDS || 0.0)

// Option setting
export const options = {
  insecureSkipTLSVerify: true,

  scenarios: {
    list: {
      executor: 'per-vu-iterations',
      exec: 'list',
      vus: vus,
      iterations: perVuIterations,
      maxDuration: '24h',
    }
  },
  thresholds: {
    checks: ['rate>0.99']
  }
}

// Test functions, in order of execution

export function setup() {
  // if session cookie was specified, save it
  if (token) {
    return { R_SESS: token }
  }

  // if credentials were specified, log in
  if (username && password) {
    const res = http.post(`${baseUrl}/v3-public/localProviders/local?action=login`, JSON.stringify({
      "description": "UI session",
      "responseType": "cookie",
      "username": username,
      "password": password
    }))

    check(res, {
      'logging in returns status 200': (r) => r.status === 200,
    })

    pause()

    return http.cookieJar().cookiesForURL(res.url)
  }

  return {}
}

// Simulate a pause after a click - on average pauseSeconds, +/- a random quantity up to 50%
function pause() {
  sleep(pauseSeconds + (Math.random() - 0.5) * 2 * pauseSeconds / 2)
}

export function list(cookies, filters = "") {
  if (api === "steve") {
    const url = cluster === "local" ?
      `${baseUrl}/v1/${resource}` :
      `${baseUrl}/k8s/clusters/${cluster}/v1/${resource}`

    if (paginationStyle === "k8s") {
      listWithK8sStylePagination(url, cookies, filters)
    }
    else if (paginationStyle === "steve") {
      listWithSteveStylePagination(url, cookies, filters)
    }
    else {
      fail("Invalid PAGINATION_STYLE value: " + paginationStyle)
    }
  }
  else if (api === "norman") {
    const url = `${baseUrl}/v3/${resource}`
    listWithNormanStylePagination(url, cookies)
  }
  else {
    fail("Invalid API value: " + api)
  }
}

function listWithK8sStylePagination(url, cookies, filters) {
  let revision = null
  let continueToken = null
  while (true) {
    const fullUrl = url + "?limit=" + pageSize +
      (filters != "" && filters != "" ? "&" + filters : "") +
      (revision != null ? "&revision=" + revision : "") +
      (continueToken != null ? "&continue=" + continueToken : "") +
      urlSuffix

    const res = http.get(fullUrl, { cookies: cookies })

    const criteria = {}
    criteria[`listing ${resource} from cluster ${cluster} (steve with k8s style pagination) succeeds`] = (r) => r.status === 200
    criteria[`no slow pagination errors (410 Gone) detected`] = (r) => r.status !== 410
    check(res, criteria)

    try {
      const body = JSON.parse(res.body)
      if (body === undefined || body.continue === undefined || firstPageOnly) {
        break
      }
      if (revision == null) {
        revision = body.revision
      }
      continueToken = body.continue
    } catch (e) {
      if (e instanceof SyntaxError) {
        fail("Response body does not parse as JSON: " + res.body)
      }
      throw e
    }

    pause()
  }
}

function listWithSteveStylePagination(url, cookies, filters) {
  let i = 1
  let revision = null
  while (true) {
    const fullUrl = url + "?pagesize=" + pageSize + "&page=" + i +
      (filters != "" && filters != "" ? "&" + filters : "") +
      (revision != null ? "&revision=" + revision : "") +
      urlSuffix

    const res = http.get(fullUrl, { cookies: cookies })

    const criteria = {}
    criteria[`listing ${resource} from cluster ${cluster} (steve style pagination) succeeds`] = (r) => r.status === 200
    criteria[`no slow pagination errors (410 Gone) detected`] = (r) => r.status !== 410
    check(res, criteria)

    try {
      const body = JSON.parse(res.body)
      if (body === undefined || body.data === undefined || body.data.length === 0 || firstPageOnly) {
        break
      }
      if (revision == null) {
        revision = body.revision
      }
      i = i + 1
    }
    catch (e) {
      if (e instanceof SyntaxError) {
        fail("Response body does not parse as JSON: " + res.body)
      }
      throw e
    }

    pause()
  }
}

function listWithNormanStylePagination(url, cookies) {
  let nextUrl = url + "?limit=" + pageSize
  while (true) {
    const res = http.get(nextUrl, { cookies: cookies })

    const criteria = {}
    criteria[`listing ${resource} from cluster ${cluster} (norman style pagination) succeeds`] = (r) => r.status === 200
    criteria[`no slow pagination errors (410 Gone) detected`] = (r) => r.status !== 410
    check(res, criteria)

    try {
      const body = JSON.parse(res.body)
      if (body === undefined || body.pagination === undefined || body.pagination.partial === undefined || body.pagination.next === undefined) {
        break
      }
      nextUrl = body.pagination.next
    } catch (e) {
      if (e instanceof SyntaxError) {
        fail("Response body does not parse as JSON: " + res.body)
      }
      throw e
    }

    pause()
  }
}