var debounce = require('./index.js')
var test = require('tape')

test('debauce', function (t) {
  t.plan(3)

  var fn = debounce(function (a, b) {
    t.deepEqual(this, {call: 3}, 'context should be preserved')
    t.equal(a, 30, 'should preserve args')
    t.equal(b, 300, 'should preserve args')
  }, 10)

  fn.call({call: 1}, 10, 100)
  fn.call({call: 2}, 20, 200)

  setTimeout(function () {
    fn.call({call: 3}, 30, 300)
  }, 3)
})

test('multiple calls should extend delay', function (t) {
  t.plan(4)

  var wasDelayed = false

  var fn = debounce(function (a, b) {
    t.deepEqual(this, {call: 3}, 'context should be preserved')
    t.equal(a, 30, 'should preserve args')
    t.equal(b, 300, 'should preserve args')
    t.ok(wasDelayed, 'should have waited longer than debounce period')
  }, 6)

  setTimeout(function longer () {
    wasDelayed = true
  }, 9)

  fn.call({call: 1}, 10, 100)

  setTimeout(function () {
    fn.call({call: 2}, 20, 200)

    setTimeout(function () {
      fn.call({call: 3}, 30, 300)
    }, 5)
  }, 3)
})

test('multiple calls should not extend delay when guarantee is true', function (t) {
  t.plan(8)

  var first = true
  var wasDelayed = false

  var fn = debounce(function (a, b) {
    if (first) {
      t.deepEqual(this, {call: 2}, '1st context should be preserved')
      t.equal(a, 20, '1st should preserve 1st args')
      t.equal(b, 200, '1st should preserve 2nd args')
      t.notOk(wasDelayed, 'should not have waited longer than debounce period')
      first = false
    } else {
      t.deepEqual(this, {call: 3}, 'context should be preserved')
      t.equal(a, 30, 'should preserve args')
      t.equal(b, 300, 'should preserve args')
      t.ok(wasDelayed, 'should have waited longer than debounce period')
    }
  }, 6, false, true)

  setTimeout(function longer () {
    wasDelayed = true
  }, 7)

  fn.call({call: 1}, 10, 100)

  setTimeout(function () {
    fn.call({call: 2}, 20, 200)

    setTimeout(function () {
      fn.call({call: 3}, 30, 300)
    }, 5)
  }, 3)
})

test('at start', function (t) {
  t.plan(9)

  var callCount = 0

  var fn = debounce(function (a, b) {
    if (callCount === 0) {
      t.deepEqual(this, {call: 1}, '1st context should be preserved')
      t.equal(a, 10, '1st should preserve 1st args')
      t.equal(b, 100, '1st should preserve 2nd args')
    } else if (callCount === 1) {
      t.deepEqual(this, {call: 3}, 'context should be preserved')
      t.equal(a, 30, 'should preserve args')
      t.equal(b, 300, 'should preserve args')
    } else {
      t.deepEqual(this, {call: 4}, 'context should be preserved')
      t.equal(a, 40, 'should preserve 1st args')
      t.equal(b, 400, 'should preserve 2nd args')
    }

    callCount += 1
  }, 6, true)

  fn.call({call: 1}, 10, 100)
  fn.call({call: 2}, 20, 200)

  setTimeout(function () {
    fn.call({call: 3}, 30, 300)

    setTimeout(function () {
      fn.call({call: 4}, 40, 400)
    }, 10)

    setTimeout(function () {
      fn.call({call: 5}, 50, 500)
    }, 3)
  }, 10)
})