import {sleep} from 'k6';
import {SharedArray} from 'k6/data';
import exec from 'k6/execution';
import logging from 'k6/x/frostfs/logging';
import registry from 'k6/x/frostfs/registry';
import s3 from 'k6/x/frostfs/s3';
import stats from 'k6/x/frostfs/stats';

import {generateS3Key} from './libs/keygen.js';
import {parseEnv} from './libs/env-parser.js';
import {textSummary} from './libs/k6-summary-0.0.2.js';
import {newGenerator} from './libs/datagen.js';

parseEnv();

const obj_list = new SharedArray(
    'obj_list',
    function() { return JSON.parse(open(__ENV.PREGEN_JSON)).objects; });

const bucket_list = new SharedArray(
    'bucket_list',
    function() { return JSON.parse(open(__ENV.PREGEN_JSON)).buckets; });

const read_size = JSON.parse(open(__ENV.PREGEN_JSON)).obj_size;
const summary_json = __ENV.SUMMARY_JSON || '/tmp/summary.json';

const no_verify_ssl = __ENV.NO_VERIFY_SSL || 'true';
const connection_args = {
  no_verify_ssl : no_verify_ssl
}
// Select random S3 endpoint for current VU
const s3_endpoints = __ENV.S3_ENDPOINTS.split(',');
const s3_endpoint =
    s3_endpoints[Math.floor(Math.random() * s3_endpoints.length)];
const s3_client = s3.connect(s3_endpoint, connection_args);
const log = logging.new().withField('endpoint', s3_endpoint);

const registry_enabled = !!__ENV.REGISTRY_FILE;
const obj_registry =
    registry_enabled ? registry.open(__ENV.REGISTRY_FILE) : undefined;

const duration = __ENV.DURATION;

if (!!__ENV.METRIC_TAGS) {
  stats.setTags(__ENV.METRIC_TAGS)
}

const read_age = __ENV.READ_AGE ? parseInt(__ENV.READ_AGE) : 10;
let obj_to_read_selector = undefined;
if (registry_enabled) {
  obj_to_read_selector = registry.getLoopedSelector(
      __ENV.REGISTRY_FILE, 'obj_to_read',
      __ENV.SELECTION_SIZE ? parseInt(__ENV.SELECTION_SIZE) : 0, {
        status : 'created',
        age : read_age,
      })
}

const scenarios = {};

const write_vu_count = parseInt(__ENV.WRITERS || '0');
const generator = newGenerator(write_vu_count > 0);
if (write_vu_count > 0) {
  scenarios.write = {
    executor : 'constant-vus',
    vus : write_vu_count,
    duration : `${duration}s`,
    exec : 'obj_write',
    gracefulStop : '5s',
  };
}

const delete_age = __ENV.DELETE_AGE ? parseInt(__ENV.DELETE_AGE) : undefined;
let obj_to_delete_selector = undefined;
let obj_to_delete_exit_on_null = undefined;
if (registry_enabled && delete_age) {
  obj_to_delete_exit_on_null = write_vu_count == 0;

  let constructor = obj_to_delete_exit_on_null ? registry.getOneshotSelector
                                               : registry.getSelector;

  obj_to_delete_selector =
      constructor(__ENV.REGISTRY_FILE, 'obj_to_delete',
                  __ENV.SELECTION_SIZE ? parseInt(__ENV.SELECTION_SIZE) : 0, {
                    status : 'created',
                    age : delete_age,
                  });
}

const read_vu_count = parseInt(__ENV.READERS || '0');
if (read_vu_count > 0) {
  scenarios.read = {
    executor : 'constant-vus',
    vus : read_vu_count,
    duration : `${duration}s`,
    exec : 'obj_read',
    gracefulStop : '5s',
  };
}

const delete_vu_count = parseInt(__ENV.DELETERS || '0');
if (delete_vu_count > 0) {
  if (!obj_to_delete_selector) {
    throw 'Positive DELETE worker number without a proper object selector';
  }

  scenarios.delete = {
    executor : 'constant-vus',
    vus : delete_vu_count,
    duration : `${duration}s`,
    exec : 'obj_delete',
    gracefulStop : '5s',
  };
}

export const options = {
  scenarios,
  setupTimeout : '5s',
};

export function setup() {
  const total_vu_count = write_vu_count + read_vu_count + delete_vu_count;

  console.log(`Pregenerated buckets:          ${bucket_list.length}`);
  console.log(`Pregenerated read object size: ${read_size}`);
  console.log(`Pregenerated total objects:    ${obj_list.length}`);
  console.log(`Reading VUs:                   ${read_vu_count}`);
  console.log(`Writing VUs:                   ${write_vu_count}`);
  console.log(`Deleting VUs:                  ${delete_vu_count}`);
  console.log(`Total VUs:                     ${total_vu_count}`);

  const start_timestamp = Date.now()
  console.log(
      `Load started at:               ${Date(start_timestamp).toString()}`)

  if (delete_vu_count > 0){
    obj_to_delete_selector.sync.add(delete_vu_count)
  }
}

export function teardown(data) {
  if (obj_registry) {
    obj_registry.close();
  }
  const end_timestamp = Date.now()
  console.log(
      `Load finished at:              ${Date(end_timestamp).toString()}`)
}

export function handleSummary(data) {
  return {
    'stdout' : textSummary(data, {indent : ' ', enableColors : false}),
    [summary_json] : JSON.stringify(data),
  };
}

export function obj_write() {
  if (__ENV.SLEEP_WRITE) {
    sleep(__ENV.SLEEP_WRITE);
  }

  const key = generateS3Key();
  const bucket = bucket_list[Math.floor(Math.random() * bucket_list.length)];

  const payload = generator.genPayload();
  const resp = s3_client.put(bucket, key, payload);
  if (!resp.success) {
    log.withFields({bucket : bucket, key : key}).error(resp.error);
    return;
  }

  if (obj_registry) {
    obj_registry.addObject('', '', bucket, key, payload.hash());
  }
}

export function obj_read() {
  if (__ENV.SLEEP_READ) {
    sleep(__ENV.SLEEP_READ);
  }

  if (obj_to_read_selector) {
    const obj = obj_to_read_selector.nextObject();
    if (!obj) {
      return;
    }
    const resp = s3_client.get(obj.s3_bucket, obj.s3_key)
    if (!resp.success) {
      log.withFields({bucket : obj.s3_bucket, key : obj.s3_key})
          .error(resp.error);
    }
    return
  }

  const obj = obj_list[Math.floor(Math.random() * obj_list.length)];

  const resp = s3_client.get(obj.bucket, obj.object);
  if (!resp.success) {
    log.withFields({bucket : obj.bucket, key : obj.object}).error(resp.error);
  }
}

export function obj_delete() {
  if (__ENV.SLEEP_DELETE) {
    sleep(__ENV.SLEEP_DELETE);
  }

  const obj = obj_to_delete_selector.nextObject();
  if (!obj) {
    if (obj_to_delete_exit_on_null) {
      obj_to_delete_selector.sync.done()
      obj_to_delete_selector.sync.wait()
      exec.test.abort("No more objects to select");
    }
    return;
  }

  const resp = s3_client.delete(obj.s3_bucket, obj.s3_key);
  if (!resp.success) {
    log.withFields({bucket : obj.s3_bucket, key : obj.s3_key, op : 'DELETE'})
        .error(resp.error);
    return;
  }

  obj_registry.deleteObject(obj.id);
}