bootstrap.js

      doAnimate ?
        this.$backdrop
          .one($.support.transition.end, callback)
          .emulateTransitionEnd(150) :
        callback()

    } else if (!this.isShown && this.$backdrop) {
      this.$backdrop.removeClass('in')

      $.support.transition && this.$element.hasClass('fade')?
        this.$backdrop
          .one($.support.transition.end, callback)
          .emulateTransitionEnd(150) :
        callback()

    } else if (callback) {
      callback()
    }
  }


  // MODAL PLUGIN DEFINITION
  // =======================

  var old = $.fn.modal

  $.fn.modal = function (option, _relatedTarget) {
    return this.each(function () {
      var $this   = $(this)
      var data    = $this.data('bs.modal')
      var options = $.extend({}, Modal.DEFAULTS, $this.data(), typeof option == 'object' && option)

      if (!data) $this.data('bs.modal', (data = new Modal(this, options)))
      if (typeof option == 'string') data[option](_relatedTarget)
      else if (options.show) data.show(_relatedTarget)
    })
  }

  $.fn.modal.Constructor = Modal


  // MODAL NO CONFLICT
  // =================

  $.fn.modal.noConflict = function () {
    $.fn.modal = old
    return this
  }


  // MODAL DATA-API
  // ==============

  $(document).on('click.bs.modal.data-api', '[data-toggle="modal"]', function (e) {
    var $this   = $(this)
    var href    = $this.attr('href')
    var $target = $($this.attr('data-target') || (href && href.replace(/.*(?=#[^\s]+$)/, ''))) //strip for ie7
    var option  = $target.data('modal') ? 'toggle' : $.extend({ remote: !/#/.test(href) && href }, $target.data(), $this.data())

    e.preventDefault()

    $target
      .modal(option, this)
      .one('hide', function () {
        $this.is(':visible') && $this.focus()
      })
  })

  $(document)
    .on('show.bs.modal',  '.modal', function () { $(document.body).addClass('modal-open') })
    .on('hidden.bs.modal', '.modal', function () { $(document.body).removeClass('modal-open') })

}(window.jQuery);

/* ========================================================================
 * Bootstrap: tooltip.js v3.0.0
 * http://twbs.github.com/bootstrap/javascript.html#tooltip
 * Inspired by the original jQuery.tipsy by Jason Frame
 * ========================================================================
 * Copyright 2012 Twitter, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ======================================================================== */


+function ($) { "use strict";

  // TOOLTIP PUBLIC CLASS DEFINITION
  // ===============================

  var Tooltip = function (element, options) {
    this.type       =
    this.options    =
    this.enabled    =
    this.timeout    =
    this.hoverState =
    this.$element   = null

    this.init('tooltip', element, options)
  }

  Tooltip.DEFAULTS = {
    animation: true
  , placement: 'top'
  , selector: false
  , template: '<div class="tooltip"><div class="tooltip-arrow"></div><div class="tooltip-inner"></div></div>'
  , trigger: 'hover focus'
  , title: ''
  , delay: 0
  , html: false
  , container: false
  }

  Tooltip.prototype.init = function (type, element, options) {
    this.enabled  = true
    this.type     = type
    this.$element = $(element)
    this.options  = this.getOptions(options)

    var triggers = this.options.trigger.split(' ')

    for (var i = triggers.length; i--;) {
      var trigger = triggers[i]

      if (trigger == 'click') {
        this.$element.on('click.' + this.type, this.options.selector, $.proxy(this.toggle, this))
      } else if (trigger != 'manual') {
        var eventIn  = trigger == 'hover' ? 'mouseenter' : 'focus'
        var eventOut = trigger == 'hover' ? 'mouseleave' : 'blur'

        this.$element.on(eventIn  + '.' + this.type, this.options.selector, $.proxy(this.enter, this))
        this.$element.on(eventOut + '.' + this.type, this.options.selector, $.proxy(this.leave, this))
      }
    }

    this.options.selector ?
      (this._options = $.extend({}, this.options, { trigger: 'manual', selector: '' })) :
      this.fixTitle()
  }

  Tooltip.prototype.getDefaults = function () {
    return Tooltip.DEFAULTS
  }

  Tooltip.prototype.getOptions = function (options) {
    options = $.extend({}, this.getDefaults(), this.$element.data(), options)

    if (options.delay && typeof options.delay == 'number') {
      options.delay = {
        show: options.delay
      , hide: options.delay
      }
    }

    return options
  }

  Tooltip.prototype.getDelegateOptions = function () {
    var options  = {}
    var defaults = this.getDefaults()

    this._options && $.each(this._options, function (key, value) {
      if (defaults[key] != value) options[key] = value
    })

    return options
  }

  Tooltip.prototype.enter = function (obj) {
    var self = obj instanceof this.constructor ?
      obj : $(obj.currentTarget)[this.type](this.getDelegateOptions()).data('bs.' + this.type)

    clearTimeout(self.timeout)

    self.hoverState = 'in'

    if (!self.options.delay || !self.options.delay.show) return self.show()

    self.timeout = setTimeout(function () {
      if (self.hoverState == 'in') self.show()
    }, self.options.delay.show)
  }

  Tooltip.prototype.leave = function (obj) {
    var self = obj instanceof this.constructor ?
      obj : $(obj.currentTarget)[this.type](this.getDelegateOptions()).data('bs.' + this.type)

    clearTimeout(self.timeout)

    self.hoverState = 'out'

    if (!self.options.delay || !self.options.delay.hide) return self.hide()

    self.timeout = setTimeout(function () {
      if (self.hoverState == 'out') self.hide()
    }, self.options.delay.hide)
  }

  Tooltip.prototype.show = function () {
    var e = $.Event('show.bs.'+ this.type)

    if (this.hasContent() && this.enabled) {
      this.$element.trigger(e)

      if (e.isDefaultPrevented()) return

      var $tip = this.tip()

      this.setContent()

      if (this.options.animation) $tip.addClass('fade')

      var placement = typeof this.options.placement == 'function' ?
        this.options.placement.call(this, $tip[0], this.$element[0]) :
        this.options.placement

      var autoToken = /\s?auto?\s?/i
      var autoPlace = autoToken.test(placement)
      if (autoPlace) placement = placement.replace(autoToken, '') || 'top'

      $tip
        .detach()
        .css({ top: 0, left: 0, display: 'block' })
        .addClass(placement)

      this.options.container ? $tip.appendTo(this.options.container) : $tip.insertAfter(this.$element)

      var pos          = this.getPosition()
      var actualWidth  = $tip[0].offsetWidth
      var actualHeight = $tip[0].offsetHeight

      if (autoPlace) {
        var $parent = this.$element.parent()

        var orgPlacement = placement
        var docScroll    = document.documentElement.scrollTop || document.body.scrollTop
        var parentWidth  = this.options.container == 'body' ? window.innerWidth  : $parent.outerWidth()
        var parentHeight = this.options.container == 'body' ? window.innerHeight : $parent.outerHeight()
        var parentLeft   = this.options.container == 'body' ? 0 : $parent.offset().left

        placement = placement == 'bottom' && pos.top   + pos.height  + actualHeight - docScroll > parentHeight  ? 'top'    :
                    placement == 'top'    && pos.top   - docScroll   - actualHeight < 0                         ? 'bottom' :
                    placement == 'right'  && pos.right + actualWidth > parentWidth                              ? 'left'   :
                    placement == 'left'   && pos.left  - actualWidth < parentLeft                               ? 'right'  :
                    placement

        $tip
          .removeClass(orgPlacement)
          .addClass(placement)
      }

      var calculatedOffset = this.getCalculatedOffset(placement, pos, actualWidth, actualHeight)

      this.applyPlacement(calculatedOffset, placement)
      this.$element.trigger('shown.bs.' + this.type)
    }
  }

  Tooltip.prototype.applyPlacement = function(offset, placement) {
    var replace
    var $tip   = this.tip()
    var width  = $tip[0].offsetWidth
    var height = $tip[0].offsetHeight

    // manually read margins because getBoundingClientRect includes difference
    var marginTop = parseInt($tip.css('margin-top'), 10)
    var marginLeft = parseInt($tip.css('margin-left'), 10)

    // we must check for NaN for ie 8/9
    if (isNaN(marginTop))  marginTop  = 0
    if (isNaN(marginLeft)) marginLeft = 0

    offset.top  = offset.top  + marginTop
    offset.left = offset.left + marginLeft

    $tip
      .offset(offset)
      .addClass('in')

    // check to see if placing tip in new offset caused the tip to resize itself
    var actualWidth  = $tip[0].offsetWidth
    var actualHeight = $tip[0].offsetHeight

    if (placement == 'top' && actualHeight != height) {
      replace = true
      offset.top = offset.top + height - actualHeight
    }

    if (/bottom|top/.test(placement)) {
      var delta = 0

      if (offset.left < 0) {
        delta       = offset.left * -2
        offset.left = 0

        $tip.offset(offset)

        actualWidth  = $tip[0].offsetWidth
        actualHeight = $tip[0].offsetHeight
      }

      this.replaceArrow(delta - width + actualWidth, actualWidth, 'left')
    } else {
      this.replaceArrow(actualHeight - height, actualHeight, 'top')
    }

    if (replace) $tip.offset(offset)
  }

  Tooltip.prototype.replaceArrow = function(delta, dimension, position) {
    this.arrow().css(position, delta ? (50 * (1 - delta / dimension) + "%") : '')
  }

  Tooltip.prototype.setContent = function () {
    var $tip  = this.tip()
    var title = this.getTitle()

    $tip.find('.tooltip-inner')[this.options.html ? 'html' : 'text'](title)
    $tip.removeClass('fade in top bottom left right')
  }

  Tooltip.prototype.hide = function () {
    var that = this
    var $tip = this.tip()
    var e    = $.Event('hide.bs.' + this.type)

    function complete() {
      if (that.hoverState != 'in') $tip.detach()
    }

    this.$element.trigger(e)

    if (e.isDefaultPrevented()) return

    $tip.removeClass('in')

    $.support.transition && this.$tip.hasClass('fade') ?
      $tip
        .one($.support.transition.end, complete)
        .emulateTransitionEnd(150) :
      complete()

    this.$element.trigger('hidden.bs.' + this.type)

    return this
  }

  Tooltip.prototype.fixTitle = function () {
    var $e = this.$element
    if ($e.attr('title') || typeof($e.attr('data-original-title')) != 'string') {
      $e.attr('data-original-title', $e.attr('title') || '').attr('title', '')
    }
  }

  Tooltip.prototype.hasContent = function () {
    return this.getTitle()
  }

  Tooltip.prototype.getPosition = function () {
    var el = this.$element[0]
    return $.extend({}, (typeof el.getBoundingClientRect == 'function') ? el.getBoundingClientRect() : {
      width: el.offsetWidth
    , height: el.offsetHeight
    }, this.$element.offset())
  }

  Tooltip.prototype.getCalculatedOffset = function (placement, pos, actualWidth, actualHeight) {
    return placement == 'bottom' ? { top: pos.top + pos.height,   left: pos.left + pos.width / 2 - actualWidth / 2  } :
           placement == 'top'    ? { top: pos.top - actualHeight, left: pos.left + pos.width / 2 - actualWidth / 2  } :
           placement == 'left'   ? { top: pos.top + pos.height / 2 - actualHeight / 2, left: pos.left - actualWidth } :
        /* placement == 'right' */ { top: pos.top + pos.height / 2 - actualHeight / 2, left: pos.left + pos.width   }
  }

  Tooltip.prototype.getTitle = function () {
    var title
    var $e = this.$element
    var o  = this.options

    title = $e.attr('data-original-title')
      || (typeof o.title == 'function' ? o.title.call($e[0]) :  o.title)

    return title
  }

  Tooltip.prototype.tip = function () {
    return this.$tip = this.$tip || $(this.options.template)
  }

  Tooltip.prototype.arrow = function () {
    return this.$arrow = this.$arrow || this.tip().find('.tooltip-arrow')
  }

  Tooltip.prototype.validate = function () {
    if (!this.$element[0].parentNode) {
      this.hide()
      this.$element = null
      this.options  = null
    }
  }

  Tooltip.prototype.enable = function () {
    this.enabled = true
  }

  Tooltip.prototype.disable = function () {
    this.enabled = false
  }

  Tooltip.prototype.toggleEnabled = function () {
    this.enabled = !this.enabled
  }

  Tooltip.prototype.toggle = function (e) {
    var self = e ? $(e.currentTarget)[this.type](this.getDelegateOptions()).data('bs.' + this.type) : this
    self.tip().hasClass('in') ? self.leave(self) : self.enter(self)
  }

  Tooltip.prototype.destroy = function () {
    this.hide().$element.off('.' + this.type).removeData('bs.' + this.type)
  }


  // TOOLTIP PLUGIN DEFINITION
  // =========================

  var old = $.fn.tooltip

  $.fn.tooltip = function (option) {
    return this.each(function () {
      var $this   = $(this)
      var data    = $this.data('bs.tooltip')
      var options = typeof option == 'object' && option

      if (!data) $this.data('bs.tooltip', (data = new Tooltip(this, options)))
      if (typeof option == 'string') data[option]()
    })
  }

  $.fn.tooltip.Constructor = Tooltip


  // TOOLTIP NO CONFLICT
  // ===================

  $.fn.tooltip.noConflict = function () {
    $.fn.tooltip = old
    return this
  }

}(window.jQuery);

/* ========================================================================
 * Bootstrap: popover.js v3.0.0
 * http://twbs.github.com/bootstrap/javascript.html#popovers
 * ========================================================================
 * Copyright 2012 Twitter, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ======================================================================== */


+function ($) { "use strict";

  // POPOVER PUBLIC CLASS DEFINITION
  // ===============================

  var Popover = function (element, options) {
    this.init('popover', element, options)
  }

  if (!$.fn.tooltip) throw new Error('Popover requires tooltip.js')

  Popover.DEFAULTS = $.extend({} , $.fn.tooltip.Constructor.DEFAULTS, {
    placement: 'right'
  , trigger: 'click'
  , content: ''
  , template: '<div class="popover"><div class="arrow"></div><h3 class="popover-title"></h3><div class="popover-content"></div></div>'
  })


  // NOTE: POPOVER EXTENDS tooltip.js
  // ================================

  Popover.prototype = $.extend({}, $.fn.tooltip.Constructor.prototype)

  Popover.prototype.constructor = Popover

  Popover.prototype.getDefaults = function () {
    return Popover.DEFAULTS
  }

  Popover.prototype.setContent = function () {
    var $tip    = this.tip()
    var title   = this.getTitle()
    var content = this.getContent()

    $tip.find('.popover-title')[this.options.html ? 'html' : 'text'](title)
    $tip.find('.popover-content')[this.options.html ? 'html' : 'text'](content)

    $tip.removeClass('fade top bottom left right in')

    // IE8 doesn't accept hiding via the `:empty` pseudo selector, we have to do
    // this manually by checking the contents.
    if (!$tip.find('.popover-title').html()) $tip.find('.popover-title').hide()
  }

  Popover.prototype.hasContent = function () {
    return this.getTitle() || this.getContent()
  }

  Popover.prototype.getContent = function () {
    var $e = this.$element
    var o  = this.options

    return $e.attr('data-content')
      || (typeof o.content == 'function' ?
            o.content.call($e[0]) :
            o.content)
  }

  Popover.prototype.arrow = function () {
    return this.$arrow = this.$arrow || this.tip().find('.arrow')
  }

  Popover.prototype.tip = function () {
    if (!this.$tip) this.$tip = $(this.options.template)
    return this.$tip
  }


  // POPOVER PLUGIN DEFINITION
  // =========================

  var old = $.fn.popover

  $.fn.popover = function (option) {
    return this.each(function () {
      var $this   = $(this)
      var data    = $this.data('bs.popover')
      var options = typeof option == 'object' && option

      if (!data) $this.data('bs.popover', (data = new Popover(this, options)))
      if (typeof option == 'string') data[option]()
    })
  }

  $.fn.popover.Constructor = Popover


  // POPOVER NO CONFLICT
  // ===================

  $.fn.popover.noConflict = function () {
    $.fn.popover = old
    return this
  }

}(window.jQuery);

/* ========================================================================
 * Bootstrap: scrollspy.js v3.0.0
 * http://twbs.github.com/bootstrap/javascript.html#scrollspy
 * ========================================================================
 * Copyright 2012 Twitter, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ======================================================================== */


+function ($) { "use strict";

  // SCROLLSPY CLASS DEFINITION
  // ==========================

  function ScrollSpy(element, options) {
    var href
    var process  = $.proxy(this.process, this)

    this.$element       = $(element).is('body') ? $(window) : $(element)
    this.$body          = $('body')
    this.$scrollElement = this.$element.on('scroll.bs.scroll-spy.data-api', process)
    this.options        = $.extend({}, ScrollSpy.DEFAULTS, options)
    this.selector       = (this.options.target
      || ((href = $(element).attr('href')) && href.replace(/.*(?=#[^\s]+$)/, '')) //strip for ie7
      || '') + ' .nav li > a'
    this.offsets        = $([])
    this.targets        = $([])
    this.activeTarget   = null

    this.refresh()
    this.process()
  }

  ScrollSpy.DEFAULTS = {
    offset: 10
  }

  ScrollSpy.prototype.refresh = function () {
    var offsetMethod = this.$element[0] == window ? 'offset' : 'position'

    this.offsets = $([])
    this.targets = $([])

    var self     = this
    var $targets = this.$body
      .find(this.selector)
      .map(function () {
        var $el   = $(this)
        var href  = $el.data('target') || $el.attr('href')
        var $href = /^#\w/.test(href) && $(href)

        return ($href
          && $href.length
          && [[ $href[offsetMethod]().top + (!$.isWindow(self.$scrollElement.get(0)) && self.$scrollElement.scrollTop()), href ]]) || null
      })
      .sort(function (a, b) { return a[0] - b[0] })
      .each(function () {
        self.offsets.push(this[0])
        self.targets.push(this[1])
      })
  }

  ScrollSpy.prototype.process = function () {
    var scrollTop    = this.$scrollElement.scrollTop() + this.options.offset
    var scrollHeight = this.$scrollElement[0].scrollHeight || this.$body[0].scrollHeight
    var maxScroll    = scrollHeight - this.$scrollElement.height()
    var offsets      = this.offsets
    var targets      = this.targets
    var activeTarget = this.activeTarget
    var i

    if (scrollTop >= maxScroll) {
      return activeTarget != (i = targets.last()[0]) && this.activate(i)
    }

    for (i = offsets.length; i--;) {
      activeTarget != targets[i]
        && scrollTop >= offsets[i]
        && (!offsets[i + 1] || scrollTop <= offsets[i + 1])
        && this.activate( targets[i] )
    }
  }

  ScrollSpy.prototype.activate = function (target) {
    this.activeTarget = target

    $(this.selector)
      .parents('.active')
      .removeClass('active')

    var selector = this.selector
      + '[data-target="' + target + '"],'
      + this.selector + '[href="' + target + '"]'

    var active = $(selector)
      .parents('li')
      .addClass('active')

    if (active.parent('.dropdown-menu').length)  {
      active = active
        .closest('li.dropdown')
        .addClass('active')
    }

    active.trigger('activate')
  }


  // SCROLLSPY PLUGIN DEFINITION
  // ===========================

  var old = $.fn.scrollspy

  $.fn.scrollspy = function (option) {
    return this.each(function () {
      var $this   = $(this)
      var data    = $this.data('bs.scrollspy')
      var options = typeof option == 'object' && option

      if (!data) $this.data('bs.scrollspy', (data = new ScrollSpy(this, options)))
      if (typeof option == 'string') data[option]()
    })
  }

  $.fn.scrollspy.Constructor = ScrollSpy


  // SCROLLSPY NO CONFLICT
  // =====================

  $.fn.scrollspy.noConflict = function () {
    $.fn.scrollspy = old
    return this
  }


  // SCROLLSPY DATA-API
  // ==================

  $(window).on('load', function () {
    $('[data-spy="scroll"]').each(function () {
      var $spy = $(this)
      $spy.scrollspy($spy.data())
    })
  })

}(window.jQuery);

/* ========================================================================
 * Bootstrap: tab.js v3.0.0
 * http://twbs.github.com/bootstrap/javascript.html#tabs
 * ========================================================================
 * Copyright 2012 Twitter, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ======================================================================== */


+function ($) { "use strict";

  // TAB CLASS DEFINITION
  // ====================

  var Tab = function (element) {
    this.element = $(element)
  }

  Tab.prototype.show = function () {
    var $this    = this.element
    var $ul      = $this.closest('ul:not(.dropdown-menu)')
    var selector = $this.data('target')

    if (!selector) {
      selector = $this.attr('href')
      selector = selector && selector.replace(/.*(?=#[^\s]*$)/, '') //strip for ie7
    }

    if ($this.parent('li').hasClass('active')) return

    var previous = $ul.find('.active:last a')[0]
    var e        = $.Event('show.bs.tab', {
      relatedTarget: previous
    })

    $this.trigger(e)

    if (e.isDefaultPrevented()) return

    var $target = $(selector)

    this.activate($this.parent('li'), $ul)
    this.activate($target, $target.parent(), function () {
      $this.trigger({
        type: 'shown.bs.tab'
      , relatedTarget: previous
      })
    })
  }

  Tab.prototype.activate = function (element, container, callback) {
    var $active    = container.find('> .active')
    var transition = callback
      && $.support.transition
      && $active.hasClass('fade')

    function next() {
      $active
        .removeClass('active')
        .find('> .dropdown-menu > .active')
        .removeClass('active')

      element.addClass('active')

      if (transition) {
        element[0].offsetWidth // reflow for transition
        element.addClass('in')
      } else {
        element.removeClass('fade')
      }

      if (element.parent('.dropdown-menu')) {
        element.closest('li.dropdown').addClass('active')
      }

      callback && callback()
    }

    transition ?
      $active
        .one($.support.transition.end, next)
        .emulateTransitionEnd(150) :
      next()

    $active.removeClass('in')
  }


  // TAB PLUGIN DEFINITION
  // =====================

  var old = $.fn.tab

  $.fn.tab = function ( option ) {
    return this.each(function () {
      var $this = $(this)
      var data  = $this.data('bs.tab')

      if (!data) $this.data('bs.tab', (data = new Tab(this)))
      if (typeof option == 'string') data[option]()
    })
  }

  $.fn.tab.Constructor = Tab


  // TAB NO CONFLICT
  // ===============

  $.fn.tab.noConflict = function () {
    $.fn.tab = old
    return this
  }


  // TAB DATA-API
  // ============

  $(document).on('click.bs.tab.data-api', '[data-toggle="tab"], [data-toggle="pill"]', function (e) {
    e.preventDefault()
    $(this).tab('show')
  })

}(window.jQuery);

/* ========================================================================
 * Bootstrap: affix.js v3.0.0
 * http://twbs.github.com/bootstrap/javascript.html#affix
 * ========================================================================
 * Copyright 2012 Twitter, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ======================================================================== */


+function ($) { "use strict";

  // AFFIX CLASS DEFINITION
  // ======================

  var Affix = function (element, options) {
    this.options = $.extend({}, Affix.DEFAULTS, options)
    this.$window = $(window)
      .on('scroll.bs.affix.data-api', $.proxy(this.checkPosition, this))
      .on('click.bs.affix.data-api',  $.proxy(this.checkPositionWithEventLoop, this))

    this.$element = $(element)
    this.affixed  =
    this.unpin    = null

    this.checkPosition()
  }

  Affix.RESET = 'affix affix-top affix-bottom'

  Affix.DEFAULTS = {
    offset: 0
  }

  Affix.prototype.checkPositionWithEventLoop = function () {
    setTimeout($.proxy(this.checkPosition, this), 1)
  }

  Affix.prototype.checkPosition = function () {
    if (!this.$element.is(':visible')) return

    var scrollHeight = $(document).height()
    var scrollTop    = this.$window.scrollTop()
    var position     = this.$element.offset()
    var offset       = this.options.offset
    var offsetTop    = offset.top
    var offsetBottom = offset.bottom

    if (typeof offset != 'object')         offsetBottom = offsetTop = offset
    if (typeof offsetTop == 'function')    offsetTop    = offset.top()
    if (typeof offsetBottom == 'function') offsetBottom = offset.bottom()

    var affix = this.unpin   != null && (scrollTop + this.unpin <= position.top) ? false :
                offsetBottom != null && (position.top + this.$element.height() >= scrollHeight - offsetBottom) ? 'bottom' :
                offsetTop    != null && (scrollTop <= offsetTop) ? 'top' : false

    if (this.affixed === affix) return
    if (this.unpin) this.$element.css('top', '')

    this.affixed = affix
    this.unpin   = affix == 'bottom' ? position.top - scrollTop : null

    this.$element.removeClass(Affix.RESET).addClass('affix' + (affix ? '-' + affix : ''))

    if (affix == 'bottom') {
      this.$element.offset({ top: document.body.offsetHeight - offsetBottom - this.$element.height() })
    }
  }


  // AFFIX PLUGIN DEFINITION
  // =======================

  var old = $.fn.affix

  $.fn.affix = function (option) {
    return this.each(function () {
      var $this   = $(this)
      var data    = $this.data('bs.affix')
      var options = typeof option == 'object' && option

      if (!data) $this.data('bs.affix', (data = new Affix(this, options)))
      if (typeof option == 'string') data[option]()
    })
  }

  $.fn.affix.Constructor = Affix


  // AFFIX NO CONFLICT
  // =================

  $.fn.affix.noConflict = function () {
    $.fn.affix = old
    return this
  }


  // AFFIX DATA-API
  // ==============

  $(window).on('load', function () {
    $('[data-spy="affix"]').each(function () {
      var $spy = $(this)
      var data = $spy.data()

      data.offset = data.offset || {}

      if (data.offsetBottom) data.offset.bottom = data.offsetBottom
      if (data.offsetTop)    data.offset.top    = data.offsetTop

      $spy.affix(data)
    })
  })