;(function ($) {
  /**
   * Generate an indented list of links from a nav. Meant for use with panel().
   * @return {jQuery} jQuery object.
   */
  $.fn.navList = function () {
    var $this = $(this)
    ;($a = $this.find('a')), (b = [])

    $a.each(function () {
      var $this = $(this),
        indent = Math.max(0, $this.parents('li').length - 1),
        href = $this.attr('href'),
        target = $this.attr('target')

      b.push(
        '<a ' +
          'class="link depth-' +
          indent +
          '"' +
          (typeof target !== 'undefined' && target != '' ? ' target="' + target + '"' : '') +
          (typeof href !== 'undefined' && href != '' ? ' href="' + href + '"' : '') +
          '>' +
          '<span class="indent-' +
          indent +
          '"></span>' +
          $this.text() +
          '</a>'
      )
    })

    return b.join('')
  }

  /**
   * Panel-ify an element.
   * @param {object} userConfig User config.
   * @return {jQuery} jQuery object.
   */
  $.fn.panel = function (userConfig) {
    // No elements?
    if (this.length == 0) return $this

    // Multiple elements?
    if (this.length > 1) {
      for (var i = 0; i < this.length; i++) $(this[i]).panel(userConfig)

      return $this
    }

    // Vars.
    var $this = $(this),
      $body = $('body'),
      $window = $(window),
      id = $this.attr('id'),
      config

    // Config.
    config = $.extend(
      {
        // Delay.
        delay: 0,

        // Hide panel on link click.
        hideOnClick: false,

        // Hide panel on escape keypress.
        hideOnEscape: false,

        // Hide panel on swipe.
        hideOnSwipe: false,

        // Reset scroll position on hide.
        resetScroll: false,

        // Reset forms on hide.
        resetForms: false,

        // Side of viewport the panel will appear.
        side: null,

        // Target element for "class".
        target: $this,

        // Class to toggle.
        visibleClass: 'visible',
      },
      userConfig
    )

    // Expand "target" if it's not a jQuery object already.
    if (typeof config.target != 'jQuery') config.target = $(config.target)

    // Panel.

    // Methods.
    $this._hide = function (event) {
      // Already hidden? Bail.
      if (!config.target.hasClass(config.visibleClass)) return

      // If an event was provided, cancel it.
      if (event) {
        event.preventDefault()
        event.stopPropagation()
      }

      // Hide.
      config.target.removeClass(config.visibleClass)

      // Post-hide stuff.
      window.setTimeout(function () {
        // Reset scroll position.
        if (config.resetScroll) $this.scrollTop(0)

        // Reset forms.
        if (config.resetForms)
          $this.find('form').each(function () {
            this.reset()
          })
      }, config.delay)
    }

    // Vendor fixes.
    $this.css('-ms-overflow-style', '-ms-autohiding-scrollbar').css('-webkit-overflow-scrolling', 'touch')

    // Hide on click.
    if (config.hideOnClick) {
      $this.find('a').css('-webkit-tap-highlight-color', 'rgba(0,0,0,0)')

      $this.on('click', 'a', function (event) {
        var $a = $(this),
          href = $a.attr('href'),
          target = $a.attr('target')

        if (!href || href == '#' || href == '' || href == '#' + id) return

        // Cancel original event.
        event.preventDefault()
        event.stopPropagation()

        // Hide panel.
        $this._hide()

        // Redirect to href.
        window.setTimeout(function () {
          if (target == '_blank') window.open(href)
          else window.location.href = href
        }, config.delay + 10)
      })
    }

    // Event: Touch stuff.
    $this.on('touchstart', function (event) {
      $this.touchPosX = event.originalEvent.touches[0].pageX
      $this.touchPosY = event.originalEvent.touches[0].pageY
    })

    $this.on('touchmove', function (event) {
      if ($this.touchPosX === null || $this.touchPosY === null) return

      var diffX = $this.touchPosX - event.originalEvent.touches[0].pageX,
        diffY = $this.touchPosY - event.originalEvent.touches[0].pageY,
        th = $this.outerHeight(),
        ts = $this.get(0).scrollHeight - $this.scrollTop()

      // Hide on swipe?
      if (config.hideOnSwipe) {
        var result = false,
          boundary = 20,
          delta = 50

        switch (config.side) {
          case 'left':
            result = diffY < boundary && diffY > -1 * boundary && diffX > delta
            break

          case 'right':
            result = diffY < boundary && diffY > -1 * boundary && diffX < -1 * delta
            break

          case 'top':
            result = diffX < boundary && diffX > -1 * boundary && diffY > delta
            break

          case 'bottom':
            result = diffX < boundary && diffX > -1 * boundary && diffY < -1 * delta
            break

          default:
            break
        }

        if (result) {
          $this.touchPosX = null
          $this.touchPosY = null
          $this._hide()

          return false
        }
      }

      // Prevent vertical scrolling past the top or bottom.
      if (($this.scrollTop() < 0 && diffY < 0) || (ts > th - 2 && ts < th + 2 && diffY > 0)) {
        event.preventDefault()
        event.stopPropagation()
      }
    })

    // Event: Prevent certain events inside the panel from bubbling.
    $this.on('click touchend touchstart touchmove', function (event) {
      event.stopPropagation()
    })

    // Event: Hide panel if a child anchor tag pointing to its ID is clicked.
    $this.on('click', 'a[href="#' + id + '"]', function (event) {
      event.preventDefault()
      event.stopPropagation()

      config.target.removeClass(config.visibleClass)
    })

    // Body.

    // Event: Hide panel on body click/tap.
    $body.on('click touchend', function (event) {
      $this._hide(event)
    })

    // Event: Toggle.
    $body.on('click', 'a[href="#' + id + '"]', function (event) {
      event.preventDefault()
      event.stopPropagation()

      config.target.toggleClass(config.visibleClass)
    })

    // Window.

    // Event: Hide on ESC.
    if (config.hideOnEscape)
      $window.on('keydown', function (event) {
        if (event.keyCode == 27) $this._hide(event)
      })

    return $this
  }

  /**
   * Apply "placeholder" attribute polyfill to one or more forms.
   * @return {jQuery} jQuery object.
   */
  $.fn.placeholder = function () {
    // Browser natively supports placeholders? Bail.
    if (typeof document.createElement('input').placeholder != 'undefined') return $(this)

    // No elements?
    if (this.length == 0) return $this

    // Multiple elements?
    if (this.length > 1) {
      for (var i = 0; i < this.length; i++) $(this[i]).placeholder()

      return $this
    }

    // Vars.
    var $this = $(this)

    // Text, TextArea.
    $this
      .find('input[type=text],textarea')
      .each(function () {
        var i = $(this)

        if (i.val() == '' || i.val() == i.attr('placeholder')) i.addClass('polyfill-placeholder').val(i.attr('placeholder'))
      })
      .on('blur', function () {
        var i = $(this)

        if (i.attr('name').match(/-polyfill-field$/)) return

        if (i.val() == '') i.addClass('polyfill-placeholder').val(i.attr('placeholder'))
      })
      .on('focus', function () {
        var i = $(this)

        if (i.attr('name').match(/-polyfill-field$/)) return

        if (i.val() == i.attr('placeholder')) i.removeClass('polyfill-placeholder').val('')
      })

    // Password.
    $this.find('input[type=password]').each(function () {
      var i = $(this)
      var x = $(
        $('<div>')
          .append(i.clone())
          .remove()
          .html()
          .replace(/type="password"/i, 'type="text"')
          .replace(/type=password/i, 'type=text')
      )

      if (i.attr('id') != '') x.attr('id', i.attr('id') + '-polyfill-field')

      if (i.attr('name') != '') x.attr('name', i.attr('name') + '-polyfill-field')

      x.addClass('polyfill-placeholder').val(x.attr('placeholder')).insertAfter(i)

      if (i.val() == '') i.hide()
      else x.hide()

      i.on('blur', function (event) {
        event.preventDefault()

        var x = i.parent().find('input[name=' + i.attr('name') + '-polyfill-field]')

        if (i.val() == '') {
          i.hide()
          x.show()
        }
      })

      x.on('focus', function (event) {
        event.preventDefault()

        var i = x.parent().find('input[name=' + x.attr('name').replace('-polyfill-field', '') + ']')

        x.hide()

        i.show().focus()
      }).on('keypress', function (event) {
        event.preventDefault()
        x.val('')
      })
    })

    // Events.
    $this
      .on('submit', function () {
        $this.find('input[type=text],input[type=password],textarea').each(function (event) {
          var i = $(this)

          if (i.attr('name').match(/-polyfill-field$/)) i.attr('name', '')

          if (i.val() == i.attr('placeholder')) {
            i.removeClass('polyfill-placeholder')
            i.val('')
          }
        })
      })
      .on('reset', function (event) {
        event.preventDefault()

        $this.find('select').val($('option:first').val())

        $this.find('input,textarea').each(function () {
          var i = $(this),
            x

          i.removeClass('polyfill-placeholder')

          switch (this.type) {
            case 'submit':
            case 'reset':
              break

            case 'password':
              i.val(i.attr('defaultValue'))

              x = i.parent().find('input[name=' + i.attr('name') + '-polyfill-field]')

              if (i.val() == '') {
                i.hide()
                x.show()
              } else {
                i.show()
                x.hide()
              }

              break

            case 'checkbox':
            case 'radio':
              i.attr('checked', i.attr('defaultValue'))
              break

            case 'text':
            case 'textarea':
              i.val(i.attr('defaultValue'))

              if (i.val() == '') {
                i.addClass('polyfill-placeholder')
                i.val(i.attr('placeholder'))
              }

              break

            default:
              i.val(i.attr('defaultValue'))
              break
          }
        })
      })

    return $this
  }

  /**
   * Moves elements to/from the first positions of their respective parents.
   * @param {jQuery} $elements Elements (or selector) to move.
   * @param {bool} condition If true, moves elements to the top. Otherwise, moves elements back to their original locations.
   */
  $.prioritize = function ($elements, condition) {
    var key = '__prioritize'

    // Expand $elements if it's not already a jQuery object.
    if (typeof $elements != 'jQuery') $elements = $($elements)

    // Step through elements.
    $elements.each(function () {
      var $e = $(this),
        $p,
        $parent = $e.parent()

      // No parent? Bail.
      if ($parent.length == 0) return

      // Not moved? Move it.
      if (!$e.data(key)) {
        // Condition is false? Bail.
        if (!condition) return

        // Get placeholder (which will serve as our point of reference for when this element needs to move back).
        $p = $e.prev()

        // Couldn't find anything? Means this element's already at the top, so bail.
        if ($p.length == 0) return

        // Move element to top of parent.
        $e.prependTo($parent)

        // Mark element as moved.
        $e.data(key, $p)
      }

      // Moved already?
      else {
        // Condition is true? Bail.
        if (condition) return

        $p = $e.data(key)

        // Move element back to its original location (using our placeholder).
        $e.insertAfter($p)

        // Unmark element as moved.
        $e.removeData(key)
      }
    })
  }
})(jQuery)