'use strict'

var tap = require('tap')
var test = tap.test
var sinon = require('sinon')
var shimmer = require('../index.js')

var outsider = 0
function counter () { return ++outsider }

var generator = {
  inc: counter
}

test('should wrap safely', function (t) {
  t.plan(9)

  t.equal(counter, generator.inc, 'method is mapped to function')
  t.doesNotThrow(function () { generator.inc() }, 'original function works')
  t.equal(1, outsider, 'calls have side effects')

  var count = 0
  function wrapper (original, name) {
    t.equal(name, 'inc')
    return function () {
      count++
      var returned = original.apply(this, arguments)
      count++
      return returned
    }
  }
  shimmer.wrap(generator, 'inc', wrapper)

  t.ok(generator.inc.__wrapped, "function tells us it's wrapped")
  t.equal(generator.inc.__original, counter, 'original function is available')
  t.doesNotThrow(function () { generator.inc() }, 'wrapping works')
  t.equal(2, count, 'both pre and post increments should have happened')
  t.equal(2, outsider, 'original function has still been called')
})

test('wrap called with no arguments', function (t) {
  t.plan(2)

  var mock = sinon.expectation
    .create('logger')
    .withExactArgs('no original function undefined to wrap')
    .once()
  shimmer({logger: mock})

  t.doesNotThrow(function () {
    shimmer.wrap()
  }, "wrapping with no arguments doesn't throw")

  t.doesNotThrow(function () {
    mock.verify()
  }, 'logger was called with the expected message')
})

test('wrap called with module but nothing else', function (t) {
  t.plan(2)

  var mock = sinon.expectation
    .create('logger')
    .withExactArgs('no original function undefined to wrap')
    .once()
  shimmer({logger: mock})

  t.doesNotThrow(function () {
    shimmer.wrap(generator)
  }, "wrapping with only 1 argument doesn't throw")

  t.doesNotThrow(function () {
    mock.verify()
  }, 'logger was called with the expected message')
})

test('wrap called with original but no wrapper', function (t) {
  t.plan(2)

  var mock = sinon.expectation
    .create('logger')
    .twice()
  shimmer({logger: mock})

  t.doesNotThrow(function () {
    shimmer.wrap(generator, 'inc')
  }, "wrapping with only original method doesn't throw")

  t.doesNotThrow(function () {
    mock.verify()
  }, 'logger was called with the expected message')
})

test('wrap called with non-function original', function (t) {
  t.plan(2)

  var mock = sinon.expectation
    .create('logger')
    .withExactArgs('original object and wrapper must be functions')
    .once()
  shimmer({logger: mock})

  t.doesNotThrow(function () {
    shimmer.wrap({orange: 'slices'}, 'orange', function () {})
  }, "wrapping non-function original doesn't throw")

  t.doesNotThrow(function () {
    mock.verify()
  }, 'logger was called with the expected message')
})

test('wrap called with non-function wrapper', function (t) {
  t.plan(2)

  var mock = sinon.expectation
    .create('logger')
    .withArgs('original object and wrapper must be functions')
    .once()
  shimmer({logger: mock})

  t.doesNotThrow(function () {
    shimmer.wrap({orange: function () {}}, 'orange', 'hamchunx')
  }, "wrapping with non-function wrapper doesn't throw")

  t.doesNotThrow(function () {
    mock.verify()
  }, 'logger was called with the expected message')
})
