// Load unmodified ES6 sort module (recommended for node environment).
  // In same way we can include any other library module e.g ('js-flock/toEnum', 'js-flock/deepFreeze'...)
  const sort = require('js-flock/sort');

  // Load transpiled/minified ES5 sort module (recommended for browser).
  const sort = require('js-flock/es5/sort');

  // Load whole unmodified ES6 library
  const jsFlock = require('js-flock');

  // Load whole transpiled/minified ES5 library
  // Note recommended in browser as bundle can be larger than we need
  const jsFlock = require('js-flock/es5');

const last = require('js-flock/last');

last([1, 4, 2]); // => 2

const persons = [{ id: 1, name: 'john'}, { id: 2, name: 'john'}, { id: 3, name: 'doe'}]

last(persons) // =>  { id: 3, name: 'doe'}
last(persons, (p) => p.name === 'john') // => { id: 2, name: 'john'}
last(persons, (p) => p.name === 'no-name') // => undefined

const empty = require('js-flock/empty');

const arr = [1, 2, 3];

// Shorthand for applying arr.splice(0, arr.length);
const emptyArr = empty(arr); // => arr ==== []
console.log(emptyArr === arr) // => true

// We can empty multiple arrays. Non array values will be ignored
empty(arr1, undefined, arr2, 3);

const single = require('js-flock/single');

// Without providing any condition
single([1]); // => 1
single([1, 2]); // => TypeError('More than one element satisfies the condition')
single([]); // => TypeError('No element satisfies the condition')

// With condition
const users = [
  { email: 'john@doe.com', fullName: 'John Doe 1' },
  { email: 'john@doe.com', fullName: 'John Doe 2' }, // NOTE same email as John Doe 1
  { email: 'mark@johnson.com', fullName: 'Mark Johnson' },
];

single(users, user => user.email === 'mark@johnson.com'); // { email: 'mark@johnson.com', fullName: 'Mark Johnson' }
single(users, user => user.email === 'john@doe.com'); // TypeError('More than one element satisfies the condition')
single(users, user => user.email === 'no@user.com'); // TypeError('No element satisfies the condition')

const NumberIterator = require('js-flock/NumberIterator');

const numberIterator = new NumberIterator();
numberIterator.current() // => 0
numberIterator.next() // => 1
numberIterator.next() // => 2
numberIterator.current() // => 2

// When instantiating iterator we can pass optional startFrom property
const numberIterator2 = new NumberIterator({ startFrom: 10 });
numberIterator2.current() // => 10
numberIterator2.next() // => 11

const castBoolean = require('js-flock/castBoolean');

castBoolean(true); // => true
castBoolean('true'); // => true

castBoolean(undefined) // => false
castBoolean('foo') // => false

const toEnum = require('js-flock/toEnum');

const vehicleType = toEnum({
  CAR: 'C',
  TRUCK: 'T',
  AIRPLANE: 'A',
  HELICOPTER: 'H',
  canFly(type) { // Define custom helper
    return type === this.AIRPLANE || type === this.HELICOPTER;
  }
});

const vehicle = getVehicle();

if (vehicle.type === vehicleType.TRUCK) {
  // Special behaviour only for truck vehicles
}

if (vehicleType.canFly(vehicle.type)) {
  // Special behaviour for vehicles that can fly
}

// enum is immutable
vehicleType.TRUCK = 'boat'; // vehicleType.TRUCK === 'T'

// Each enum have standard helpers

vehicleType.keys(); // ['CAR', 'TRUCK', 'AIRPLANE', 'HELICOPTER'] - helper functions are not included in keys
vehicleType.values(); // ['C', 'T', 'A', 'H']

vehicleType.exists('C'); // true
vehicleType.exists('something'); // false

vehicleType.haveKey('CAR'); // true
vehicleType.haveKey('something'); // false


// We can define enum with short notation. Limitation of short notation is that we can't define custom enum helpers.

const gender = toEnum(['MAN', 'WOMEN', 'OTHER']);

gender.keys(); // ['MAN', 'WOMEN', 'OTHER']
gender.values(); // [Symbol(MAN), Symbol(Women), Symbol(OTHER)]

const singular = require('js-flock/singular');

export default {
  methods: {
    save: singular(function(done) {
      // All subsequent calls to submit will be ignored until done is called
      UserService.save(this.user)
        .then(() => { /* Success handler */ })
        .catch(() => { /* Exception handler */ })
        .then(done);
    }
  };
}

const waitFor = require('js-flock/waitFor');

const options = {
  interval: Number, // [Default: 50ms] - How frequently will check be preformed.
  timeout: Number, // [Default: 5000ms] - Timeout if function is not resolved by then.
};

// Wait for DB connection
waitFor(() => Db.connection, options)
  .then((connection) => { /* connection to DB has been established */})
  .catch(() => { /* Waiting timed out, handle the error! */ });

// Wait for DOM element to become accessible
waitFor(() => document.getElementById('elId'))
  .then(($el) => { /* Element is available now we can do manipulation with $el */})
  .catch(() => { /* Waiting timed out, handle the error! */ });

// We can abort execution of waitFor at any moment by calling abort function that is
// injected to waitFor listener as shown in example.
// NOTE: Available from v3.6.0
waitFor((abort) => {
  if(componentIsDestroyed) {
    // waitFor will immediately stop checking for presence of element
    // than/catch will never be called after calling abort
    abort();
  } else {
    return document.getElementById('elId');
  }
})
  .then(($el) => { /* Element is available now we can do manipulation with $el */})
  .catch(() => { /* Waiting timed out, handle the error! */ });

  // Any user defined function.
  rerun(Function)
    // How frequently will rerun function be called
    .every(timeInMilliseconds)
    // [Optional] Execution is stopped if falsy value is returned from function. If falsy value is returned first time rerun will never be called.
    .asLongAs(Function)
    // Execute rerun function for first time and start execution cycle
    .start()
    // [Optional] -> Attach onStop listener
    .onStop(Function)
    // [Optional] Stop function execution. Function execution can also be stoped by returning falsy value from asLongAs or by returning `false` value from within rerun function
    .stop()

  // Example
  // refreshAuthToken and isUserLoggedIn are custom function implementations
  const tenMinutesInMs = 10 * 60 * 1000;
  const refreshTokenRunner = rerun(refreshAuthToken)
    .every(tenMinutesInMs)
    .asLongAs(isUserLoggedIn);

  // Function that will be called after user log in
  // Every call to start will execute function immediately and restart execution cycle
  eventBus.$on('login', refreshTokenRunner.start);

const delay = require('js-flock/delay');

async exampleFunction() {
  bar();

  // Wait for 100 milliseconds
  // If delay time not provided it defaults ot 0ms (next tick)
  await delay(100);

  // Executed 100 milliseconds later
  baz();
}

const promiseAll = require('js-flock/promiseAll');

const objectResponse = await promiseAll({
  users: db.fetchUsers(),
  schools: db.fetchSchools(),
});

/*
  objectResponse =>
    {
      users: [{...}, {...}], // value of fetchUsers promise resolve
      schools: [{...}, {...}], // value of fetchSchools promise resolve
    }
*/

const arrayResponse = await promiseAll([db.fetchUsers(), db.fetchSchools()]);

/*
  arrayResponse => [usersResponse, schoolsResponse]
*/

const promisify = require('js-flock/promisify');
const readFile = require("fs").readFile;
const readFileAsync = promisify(readFile);

// Native version of read file
readFile('test.txt', 'utf8', (err, data) => {
  if (err) {
    console.log(err);
    return;
  }
  console.log(data);
});

// Promisify version
readFileAsync('test.txt', 'utf8')
  .then((data) => console.log(data))
  .catch((err) => console.log(err));

const fun = (cb) => cb(undefined, 'res1', 'res2');
const funAsync = promisify(fun, { multiArgs: true });

funAsync().then(([r1, r2]) => { /* r1 === res1, r2 === res2 */ });

const promisify = require('js-flock/promisify');
const fs = promisify.all(require("fs"));

// New function appended by promisify.all
fs.readFileAsync('test.txt', 'utf8')
  .then((data) => console.log(data))
  .catch((err) => console.log(err));

const withOptions = promisify.all(test, {
  suffix: String, // [default: 'Async'] - Suffix will be appended to original method name
  multiArgs: Boolean, // [default: false] Promise will resolve with array of values if true
  proto: Boolean, // [default: false] Promisify object prototype chain if true
  exclude: [String], // [default: undefined] List of object keys not to promisify
  include: [String], // [default: undefined] Promisify only provided keys
});

const collar = require('js-flock/collar');

const MAX_WAITING_TIME = 500;

// Reject HTTP request if it's not resolved in 0.5 seconds
collar(Http.get('test-url'), MAX_WAITING_TIME)
.then((response) => { /* handle response */  })
.catch((err) => {
  // CollarError = { isStrangled: true, message: 'Promise have timed out' }
  if (typeof err === 'object' && err.isStrangled) {
    console.log(err.message);
  }
});

const deepFreeze = require('js-flock/deepFreeze');

const person = {
  fullName: 'test person',
  dob: new Date(),
  address: {
    country: 'testiland',
    city: 'this one'
  }
};

Object.freeze(person);

Object.isFrozen(person); // true
Object.isFrozen(person.address); // false UH OH

deepFreeze(person);

Object.isFrozen(person); // true
Object.isFrozen(person.address); // true WE HE

// We can modify deepFreeze behaviour by providing additional options

deepFreeze(object, {
  proto: Boolean, // [default: false] - Freeze object prototype chain
  exclude: Function, // Fine tune what will be frozen by providing exclude function. Available from version [3.3.2]
});

deepFreeze(person, {
  // address object will not be frozen
  exclude(key, context) {
    return key === 'address' && context === person;
  }
});

  const sort = require('js-flock/sort');

  sort([1, 4, 2]).asc(); // => [1, 2, 4]
  sort([1, 4, 2]).desc(); // => [4, 2, 1]

  sort(persons).asc(p => p.firstName);

  // Sort persons by multiple properties
  sort(persons).desc([
    p => p.firstName
    p => p.address.city
  ]);

  // Sort in multiple directions
  sort(persons).by([
    { asc: 'name' }
    { desc: 'age' }
    { asc: p => p.address.city }
  ]);