/*jshint browser:true */
"use strict";

var open = require("../event")
var reduced = require("reducible/reduced")
var fold = require("reducers/fold")
var filter = require("reducers/filter")
var into = require("reducers/into")

function click(target) {
  var event = document.createEvent("MouseEvents")
  event.initMouseEvent("click", true, true, window, 0, 0, 0, 0, 0,
                       false, false, false, false, 0, null)
  target.dispatchEvent(event)
}

exports["test the dom events are reduced"] = function(assert) {
  var element = document.createElement("div")
  document.body.appendChild(element)


  var clicks = open(element, "click")
  var count = 0
  var result = fold(clicks, function(event, state) {
    assert.equal(event.target, element, "event target is element")
    count = count + 1
  }, 0)

  click(element)
  click(element)

  assert.equal(count, 2, "reducer was called twice")
  document.body.removeChild(element)
}

exports["test listeners removal"] = function(assert) {
  var element = document.createElement("div")
  document.body.appendChild(element)


  var clicks = open(element, "click")
  var count = 0
  var result = fold(clicks, function(event, state) {
    count = count + 1
    assert.equal(event.target, element, "event target is element")
    return reduced("stop!")
  }, 0)

  click(element)
  click(element)
  click(element)

  assert.equal(count, 1, "reducer stopped reduction early")
  assert.deepEqual(into(result), ["stop!"], "reducer accumulates value")
  document.body.removeChild(element)
}


exports["test multiple reducers"] = function(assert) {
  var element = document.createElement("div")
  document.body.appendChild(element)


  var clicks = open(element, "click")
  var profile = []

  var r1 = fold(clicks, function(event, state) {
    profile.push(1)
    assert.equal(event.target, element, "event target is element #1")
    if (profile.length === 3) return reduced("stop!")
  }, 0)

  var r2 = fold(clicks, function(event, state) {
    profile.push(2)
    assert.equal(event.target, element, "event target is element #2")
  })

  click(element)
  click(element)
  click(element)
  click(element)
  click(element)
  click(element)

  assert.deepEqual(profile, [1, 2, 1, 2, 2, 2, 2, 2],
                   "events were delivered in expected order")
  assert.deepEqual(into(r1), ["stop!"], "first reduce was stopped early")
  document.body.removeChild(element)
}

require("test").run(exports)