@class up.browser

###

up.browser = (->

u = up.util

loadPage = (url, options = {}) ->

window.console.groupEnd ||= noop

canPushState = u.memoize ->

u.isDefined(history.pushState)

# We cannot use pushState if the initial request method is a POST for two reasons:

#

# 1. Up.js replaces the initial state so it can handle the pop event when the

# user goes back to the initial URL later. If the initial request was a POST,

# Up.js will wrongly assumed that it can restore the state by reloading with GET.

#

# 2. Some browsers have a bug where the initial request method is used for all

# subsequently pushed states. That means if the user reloads the page on a later

# GET state, the browser will wrongly attempt a POST request.

# Modern Firefoxes, Chromes and IE10+ don't seem to be affected by this,

# but we saw this behavior with Safari 8 and IE9 (IE9 can't do pushState anyway).

#

# The way that we work around this is that we don't support pushState if the

# initial request method was anything other than GET (but allow the rest of the

# Up.js framework to work). This way Up.js will fall back to full page loads until

# the framework was booted from a GET request.

u.isDefined(history.pushState) && initialRequestMethod == 'get'

canCssAnimation = u.memoize ->

'transition' of document.documentElement.style

minor = parseInt(parts[1])

compatible = major >= 2 || (major == 1 && minor >= 9)

compatible or u.error("jQuery %o found, but Up.js requires 1.9+", version)

# Returns and deletes a cookie with the given name

# Inspired by Turbolinks: https://github.com/rails/turbolinks/blob/83d4b3d2c52a681f07900c28adb28bc8da604733/lib/assets/javascripts/turbolinks.coffee#L292

popCookie = (name) ->

value = document.cookie.match(new RegExp(name+"=(\\w+)"))?[1]

if u.isPresent(value)

document.cookie = name + '=; expires=Thu, 01-Jan-70 00:00:01 GMT; path=/'

value

# Server-side companion libraries like upjs-rails set this cookie so we

# have a way to detect the request method of the initial page load.

# There is no Javascript API for this.

initialRequestMethod = (popCookie('_up_request_method') || 'get').toLowerCase()

isSupported = u.memoize ->

# This is the most concise way to exclude IE8 and lower

# while keeping all relevant desktop and mobile browsers.

canInputEvent: canInputEvent

isSupported: isSupported

ensureRecentJquery: ensureRecentJquery

)()

)()