pageCache = {} cacheSize = 10 transitionCacheEnabled = false progressBar = null

currentState = null loadedAssets = null

referer = null

xhr = null

EVENTS =

BEFORE_CHANGE:  'page:before-change'
FETCH:          'page:fetch'
RECEIVE:        'page:receive'
CHANGE:         'page:change'
UPDATE:         'page:update'
LOAD:           'page:load'
RESTORE:        'page:restore'
BEFORE_UNLOAD:  'page:before-unload'
EXPIRE:         'page:expire'

fetch = (url) ->

url = new ComponentUrl url

rememberReferer()
cacheCurrentPage()
progressBar?.start()

if transitionCacheEnabled and cachedPage = transitionCacheFor(url.absolute)
  fetchHistory cachedPage
  fetchReplacement url, null, false
else
  fetchReplacement url, resetScrollPosition

transitionCacheFor = (url) ->

cachedPage = pageCache[url]
cachedPage if cachedPage and !cachedPage.transitionCacheDisabled

enableTransitionCache = (enable = true) ->

transitionCacheEnabled = enable

enableProgressBar = (enable = true) ->

return unless browserSupportsTurbolinks
if enable
  progressBar ?= new ProgressBar 'html'
else
  progressBar?.uninstall()
  progressBar = null

fetchReplacement = (url, onLoadFunction, showProgressBar = true) ->

triggerEvent EVENTS.FETCH, url: url.absolute

xhr?.abort()
xhr = new XMLHttpRequest
xhr.open 'GET', url.withoutHashForIE10compatibility(), true
xhr.setRequestHeader 'Accept', 'text/html, application/xhtml+xml, application/xml'
xhr.setRequestHeader 'X-XHR-Referer', referer

xhr.onload = ->
  triggerEvent EVENTS.RECEIVE, url: url.absolute

  if doc = processResponse()
    reflectNewUrl url
    reflectRedirectedUrl()
    changePage extractTitleAndBody(doc)...
    if showProgressBar
      progressBar?.done()
    manuallyTriggerHashChangeForFirefox()
    onLoadFunction?()
    triggerEvent EVENTS.LOAD
  else
    progressBar?.done()
    document.location.href = crossOriginRedirect() or url.absolute

if progressBar and showProgressBar
  xhr.onprogress = (event) =>
    percent = if event.lengthComputable
      event.loaded / event.total * 100
    else
      progressBar.value + (100 - progressBar.value) / 10
    progressBar.advanceTo(percent)

xhr.onloadend = -> xhr = null
xhr.onerror   = -> document.location.href = url.absolute

xhr.send()

fetchHistory = (cachedPage) ->

xhr?.abort()
changePage cachedPage.title, cachedPage.body
progressBar?.done()
recallScrollPosition cachedPage
triggerEvent EVENTS.RESTORE

cacheCurrentPage = ->

currentStateUrl = new ComponentUrl currentState.url

pageCache[currentStateUrl.absolute] =
  url:                      currentStateUrl.relative,
  body:                     document.body,
  title:                    document.title,
  positionY:                window.pageYOffset,
  positionX:                window.pageXOffset,
  cachedAt:                 new Date().getTime(),
  transitionCacheDisabled:  document.querySelector('[data-no-transition-cache]')?

constrainPageCacheTo cacheSize

pagesCached = (size = cacheSize) ->

cacheSize = parseInt(size) if /^[\d]+$/.test size

constrainPageCacheTo = (limit) ->

pageCacheKeys = Object.keys pageCache

cacheTimesRecentFirst = pageCacheKeys.map (url) ->
  pageCache[url].cachedAt
.sort (a, b) -> b - a

for key in pageCacheKeys when pageCache[key].cachedAt <= cacheTimesRecentFirst[limit]
  triggerEvent EVENTS.EXPIRE, pageCache[key]
  delete pageCache[key]

changePage = (title, body, csrfToken, runScripts) ->

triggerEvent EVENTS.BEFORE_UNLOAD
document.title = title
document.documentElement.replaceChild body, document.body
CSRFToken.update csrfToken if csrfToken?
setAutofocusElement()
executeScriptTags() if runScripts
currentState = window.history.state
triggerEvent EVENTS.CHANGE
triggerEvent EVENTS.UPDATE

executeScriptTags = ->

scripts = Array::slice.call document.body.querySelectorAll 'script:not([data-turbolinks-eval="false"])'
for script in scripts when script.type in ['', 'text/javascript']
  copy = document.createElement 'script'
  copy.setAttribute attr.name, attr.value for attr in script.attributes
  copy.async = false unless script.hasAttribute 'async'
  copy.appendChild document.createTextNode script.innerHTML
  { parentNode, nextSibling } = script
  parentNode.removeChild script
  parentNode.insertBefore copy, nextSibling
return

removeNoscriptTags = (node) ->

node.innerHTML = node.innerHTML.replace /<noscript[\S\s]*?<\/noscript>/ig, ''
node

# Firefox bug: Doesn't autofocus fields that are inserted via JavaScript setAutofocusElement = ->

autofocusElement = (list = document.querySelectorAll 'input[autofocus], textarea[autofocus]')[list.length - 1]
if autofocusElement and document.activeElement isnt autofocusElement
  autofocusElement.focus()

reflectNewUrl = (url) ->

if (url = new ComponentUrl url).absolute isnt referer
  window.history.pushState { turbolinks: true, url: url.absolute }, '', url.absolute

reflectRedirectedUrl = ->

if location = xhr.getResponseHeader 'X-XHR-Redirected-To'
  location = new ComponentUrl location
  preservedHash = if location.hasNoHash() then document.location.hash else ''
  window.history.replaceState window.history.state, '', location.href + preservedHash

crossOriginRedirect = ->

redirect if (redirect = xhr.getResponseHeader('Location'))? and (new ComponentUrl(redirect)).crossOrigin()

rememberReferer = ->

referer = document.location.href

rememberCurrentUrl = ->

window.history.replaceState { turbolinks: true, url: document.location.href }, '', document.location.href

rememberCurrentState = ->

currentState = window.history.state

# Unlike other browsers, Firefox doesn't trigger hashchange after changing the # location (via pushState) to an anchor on a different page. For example: # # /pages/one => /pages/two#with-hash # # By forcing Firefox to trigger hashchange, the rest of the code can rely on more # consistent behavior across browsers. manuallyTriggerHashChangeForFirefox = ->

if navigator.userAgent.match(/Firefox/) and !(url = (new ComponentUrl)).hasNoHash()
  window.history.replaceState currentState, '', url.withoutHash()
  document.location.hash = url.hash

recallScrollPosition = (page) ->

window.scrollTo page.positionX, page.positionY

resetScrollPosition = ->

if document.location.hash
  document.location.href = document.location.href
else
  window.scrollTo 0, 0

clone = (original) ->

return original if not original? or typeof original isnt 'object'
copy = new original.constructor()
copy[key] = clone value for key, value of original
copy

popCookie = (name) ->

value = document.cookie.match(new RegExp(name+"=(\\w+)"))?[1].toUpperCase() or ''
document.cookie = name + '=; expires=Thu, 01-Jan-70 00:00:01 GMT; path=/'
value

triggerEvent = (name, data) ->

if typeof Prototype isnt 'undefined'
  Event.fire document, name, data, true

event = document.createEvent 'Events'
event.data = data if data
event.initEvent name, true, true
document.dispatchEvent event

pageChangePrevented = (url) ->

!triggerEvent EVENTS.BEFORE_CHANGE, url: url

processResponse = ->

clientOrServerError = ->
  400 <= xhr.status < 600

validContent = ->
  (contentType = xhr.getResponseHeader('Content-Type'))? and
    contentType.match /^(?:text\/html|application\/xhtml\+xml|application\/xml)(?:;|$)/

downloadingFile = ->
  (disposition = xhr.getResponseHeader('Content-Disposition'))? and
    disposition.match /^attachment/

extractTrackAssets = (doc) ->
  for node in doc.querySelector('head').childNodes when node.getAttribute?('data-turbolinks-track')?
    node.getAttribute('src') or node.getAttribute('href')

assetsChanged = (doc) ->
  loadedAssets ||= extractTrackAssets document
  fetchedAssets  = extractTrackAssets doc
  fetchedAssets.length isnt loadedAssets.length or intersection(fetchedAssets, loadedAssets).length isnt loadedAssets.length

intersection = (a, b) ->
  [a, b] = [b, a] if a.length > b.length
  value for value in a when value in b

if not clientOrServerError() and validContent() and not downloadingFile()
  doc = createDocument xhr.responseText
  if doc and !assetsChanged doc
    return doc

extractTitleAndBody = (doc) ->

title = doc.querySelector 'title'
[ title?.textContent, removeNoscriptTags(doc.querySelector('body')), CSRFToken.get(doc).token, 'runScripts' ]

CSRFToken =

get: (doc = document) ->
  node:   tag = doc.querySelector 'meta[name="csrf-token"]'
  token:  tag?.getAttribute? 'content'

update: (latest) ->
  current = @get()
  if current.token? and latest? and current.token isnt latest
    current.node.setAttribute 'content', latest

createDocument = (html) ->

doc = document.documentElement.cloneNode()
doc.innerHTML = html
doc.head = doc.querySelector 'head'
doc.body = doc.querySelector 'body'
doc

# The ComponentUrl class converts a basic URL string into an object # that behaves similarly to document.location. # # If an instance is created from a relative URL, the current document # is used to fill in the missing attributes (protocol, host, port). class ComponentUrl

constructor: (@original = document.location.href) ->
  return @original if @original.constructor is ComponentUrl
  @_parse()

withoutHash: -> @href.replace(@hash, '').replace('#', '')

# Intention revealing function alias
withoutHashForIE10compatibility: -> @withoutHash()

hasNoHash: -> @hash.length is 0

crossOrigin: ->
  @origin isnt (new ComponentUrl).origin

_parse: ->
  (@link ?= document.createElement 'a').href = @original
  { @href, @protocol, @host, @hostname, @port, @pathname, @search, @hash } = @link
  @origin = [@protocol, '//', @hostname].join ''
  @origin += ":#{@port}" unless @port.length is 0
  @relative = [@pathname, @search, @hash].join ''
  @absolute = @href

# The Link class derives from the ComponentUrl class, but is built from an # existing link element. Provides verification functionality for Turbolinks # to use in determining whether it should process the link when clicked. class Link extends ComponentUrl

@HTML_EXTENSIONS: ['html']

@allowExtensions: (extensions...) ->
  Link.HTML_EXTENSIONS.push extension for extension in extensions
  Link.HTML_EXTENSIONS

constructor: (@link) ->
  return @link if @link.constructor is Link
  @original = @link.href
  @originalElement = @link
  @link = @link.cloneNode false
  super

shouldIgnore: ->
  @crossOrigin() or
    @_anchored() or
    @_nonHtml() or
    @_optOut() or
    @_target()

_anchored: ->
  (@hash.length > 0 or @href.charAt(@href.length - 1) is '#') and
    (@withoutHash() is (new ComponentUrl).withoutHash())

_nonHtml: ->
  @pathname.match(/\.[a-z]+$/g) and not @pathname.match(new RegExp("\\.(?:#{Link.HTML_EXTENSIONS.join('|')})?$", 'g'))

_optOut: ->
  link = @originalElement
  until ignore or link is document
    ignore = link.getAttribute('data-no-turbolink')?
    link = link.parentNode
  ignore

_target: ->
  @link.target.length isnt 0

# The Click class handles clicked links, verifying if Turbolinks should # take control by inspecting both the event and the link. If it should, # the page change process is initiated. If not, control is passed back # to the browser for default functionality. class Click

@installHandlerLast: (event) ->
  unless event.defaultPrevented
    document.removeEventListener 'click', Click.handle, false
    document.addEventListener 'click', Click.handle, false

@handle: (event) ->
  new Click event

constructor: (@event) ->
  return if @event.defaultPrevented
  @_extractLink()
  if @_validForTurbolinks()
    visit @link.href unless pageChangePrevented(@link.absolute)
    @event.preventDefault()

_extractLink: ->
  link = @event.target
  link = link.parentNode until !link.parentNode or link.nodeName is 'A'
  @link = new Link(link) if link.nodeName is 'A' and link.href.length isnt 0

_validForTurbolinks: ->
  @link? and not (@link.shouldIgnore() or @_nonStandardClick())

_nonStandardClick: ->
  @event.which > 1 or
    @event.metaKey or
    @event.ctrlKey or
    @event.shiftKey or
    @event.altKey

class ProgressBar

className = 'turbolinks-progress-bar'
# Setting the opacity to a value < 1 fixes a display issue in Safari 6 and
# iOS 6 where the progress bar would fill the entire page.
originalOpacity = 0.99

constructor: (@elementSelector) ->
  @value = 0
  @content = ''
  @speed = 300
  @opacity = originalOpacity
  @install()

install: ->
  @element = document.querySelector(@elementSelector)
  @element.classList.add(className)
  @styleElement = document.createElement('style')
  document.head.appendChild(@styleElement)
  @_updateStyle()

uninstall: ->
  @element.classList.remove(className)
  document.head.removeChild(@styleElement)

start: ->
  if @value > 0
    @_reset()
    @_reflow()

  @advanceTo(5)

advanceTo: (value) ->
  if value > @value <= 100
    @value = value
    @_updateStyle()

    if @value is 100
      @_stopTrickle()
    else if @value > 0
      @_startTrickle()

done: ->
  if @value > 0
    @advanceTo(100)
    @_finish()

_finish: ->
  @fadeTimer = setTimeout =>
    @opacity = 0
    @_updateStyle()
  , @speed / 2

  @resetTimer = setTimeout(@_reset, @speed)

_reflow: ->
  @element.offsetHeight

_reset: =>
  @_stopTimers()
  @value = 0
  @opacity = originalOpacity
  @_withSpeed(0, => @_updateStyle(true))

_stopTimers: ->
  @_stopTrickle()
  clearTimeout(@fadeTimer)
  clearTimeout(@resetTimer)

_startTrickle: ->
  return if @trickleTimer
  @trickleTimer = setTimeout(@_trickle, @speed)

_stopTrickle: ->
  clearTimeout(@trickleTimer)
  delete @trickleTimer

_trickle: =>
  @advanceTo(@value + Math.random() / 2)
  @trickleTimer = setTimeout(@_trickle, @speed)

_withSpeed: (speed, fn) ->
  originalSpeed = @speed
  @speed = speed
  result = fn()
  @speed = originalSpeed
  result

_updateStyle: (forceRepaint = false) ->
  @_changeContentToForceRepaint() if forceRepaint
  @styleElement.textContent = @_createCSSRule()

_changeContentToForceRepaint: ->
  @content = if @content is '' then ' ' else ''

_createCSSRule: ->
  """
  #{@elementSelector}.#{className}::before {
    content: '#{@content}';
    position: fixed;
    top: 0;
    left: 0;
    z-index: 2000;
    background-color: #0076ff;
    height: 3px;
    opacity: #{@opacity};
    width: #{@value}%;
    transition: width #{@speed}ms ease-out, opacity #{@speed / 2}ms ease-in;
    transform: translate3d(0,0,0);
  }
  """

# Delay execution of function long enough to miss the popstate event # some browsers fire on the initial page load. bypassOnLoadPopstate = (fn) ->

setTimeout fn, 500

installDocumentReadyPageEventTriggers = ->

document.addEventListener 'DOMContentLoaded', ( ->
  triggerEvent EVENTS.CHANGE
  triggerEvent EVENTS.UPDATE
), true

installJqueryAjaxSuccessPageUpdateTrigger = ->

if typeof jQuery isnt 'undefined'
  jQuery(document).on 'ajaxSuccess', (event, xhr, settings) ->
    return unless jQuery.trim xhr.responseText
    triggerEvent EVENTS.UPDATE

installHistoryChangeHandler = (event) ->

if event.state?.turbolinks
  if cachedPage = pageCache[(new ComponentUrl(event.state.url)).absolute]
    cacheCurrentPage()
    fetchHistory cachedPage
  else
    visit event.target.location.href

initializeTurbolinks = ->

rememberCurrentUrl()
rememberCurrentState()

document.addEventListener 'click', Click.installHandlerLast, true

window.addEventListener 'hashchange', (event) ->
  rememberCurrentUrl()
  rememberCurrentState()
, false
bypassOnLoadPopstate ->
  window.addEventListener 'popstate', installHistoryChangeHandler, false

# Handle bug in Firefox 26/27 where history.state is initially undefined historyStateIsDefined =

window.history.state != undefined or navigator.userAgent.match /Firefox\/2[6|7]/

browserSupportsPushState =

window.history and window.history.pushState and window.history.replaceState and historyStateIsDefined

browserIsntBuggy =

!navigator.userAgent.match /CriOS\//

requestMethodIsSafe =

popCookie('request_method') in ['GET','']

browserSupportsTurbolinks = browserSupportsPushState and browserIsntBuggy and requestMethodIsSafe

browserSupportsCustomEvents =

document.addEventListener and document.createEvent

if browserSupportsCustomEvents

installDocumentReadyPageEventTriggers()
installJqueryAjaxSuccessPageUpdateTrigger()

if browserSupportsTurbolinks

visit = fetch
initializeTurbolinks()

else

visit = (url) -> document.location.href = url

# Public API # Turbolinks.visit(url) # Turbolinks.pagesCached() # Turbolinks.pagesCached(20) # Turbolinks.enableTransitionCache() # Turbolinks.cacheCurrentPage() # Turbolinks.allowLinkExtensions('md') # Turbolinks.supported # Turbolinks.EVENTS @Turbolinks = {

visit,
pagesCached,
cacheCurrentPage,
enableTransitionCache,
enableProgressBar,
allowLinkExtensions: Link.allowExtensions,
supported: browserSupportsTurbolinks,
EVENTS: clone(EVENTS)

}