/*
    jQuery placeholder plugin
    by Andrey Kuzmin, @unsoundscapes
  
    Based on existing plugin http://mths.be/placeholder by @mathias
    and this demo http://robertnyman.com/2011/05/02/ by @robertnyman
  
    Adopted to toggle placeholder on user input instead of focus
  
    Released under the MIT license
  */
  
  (function (factory) {
    'use strict';
  
    if (typeof define === 'function' && define.amd) {
      // AMD. Register as anonymous module.
      define(['jquery'], factory)
    } else {
      // Browser globals.
      factory(jQuery)
    }
  }(function ($) {
    'use strict';
  
    var isInputSupported = 'placeholder' in document.createElement('input')
      , isTextareaSupported = 'placeholder' in document.createElement('textarea')
      , $placeholders = $()
  
    function getAttributes (element) {
      // Return an object of element attributes
      var newAttrs = {}
        , rinlinejQuery = /^jQuery\d+$/
  
      $.each(element.attributes, function () {
        if (this.specified && !rinlinejQuery.test(this.name)) {
          newAttrs[this.name] = this.value
        }
      })
      return newAttrs
    }
  
    function setCaretTo (element, index) {
      // Set caret to specified @index
      if (element.createTextRange) {
        var range = element.createTextRange()
        range.move('character', index)
        range.select()
      } else if (element.selectionStart !== null) {
        element.focus()
        element.setSelectionRange(index, index)
      }
    }
  
  
    function Placeholder (element, options) {
      this.options = options || {}
      this.$replacement = this.$element = $(element)
      this.initialize.apply(this, arguments)
      // Cache all elements with placeholders
      $placeholders = $placeholders.add(element)
    }
  
    Placeholder.prototype = {
  
      initialize: function () {
        this.isHidden = true
        this.placeholderAttr = this.$element.attr('placeholder')
        // do not mess with default behavior
        this.$element.removeAttr('placeholder')
        this.isPassword = this.$element.is('[type=password]')
        if (this.isPassword) this.makeReplacement()
        this.$replacement.on({
          'keydown.placeholder': $.proxy(this.hide, this)
        , 'focus.placeholder drop.placeholder click.placeholder': $.proxy(this.setCaret, this)
        })
        this.$element.on({
          'blur.placeholder keyup.placeholder': $.proxy(this.show, this)
        })
        this.show()
      }
  
      // Set or get input value
      // Setting value toggles placeholder
    , val: function (value) {
        if (value === undefined) {
          return this.isHidden ? this.$element[0].value : '';
        }
        if (value === '') {
          if (this.isHidden) {
            this.$element[0].value = value
            this.show()
          }
        } else {
          if (!this.isHidden) this.hide()
          this.$element[0].value = value
        }
        return this
      }
  
      // Hide placeholder at user input
    , hide: function (e) {
        var isActiveElement = this.$replacement.is(':focus')
        if (this.isHidden) return;
        if (!e || !(e.shiftKey && e.keyCode === 16) && e.keyCode !== 9) {
          this.isHidden = true
          if (this.isPassword) {
            this.$replacement.before(this.$element.show()).hide()
            if (isActiveElement) this.$element.focus()
          } else {
            this.$element[0].value = ''
            this.$element.removeClass(this.options.className)
          }
        }
      }
  
      // Show placeholder on blur and keyup
    , show: function (e) {
        var isActiveElement = this.$element.is(':focus')
        if (!this.isHidden) return;
        if (this.$element[0].value === '') {
          this.isHidden = false
          if (this.isPassword) {
            this.$element.before(this.$replacement.show()).hide()
            if (isActiveElement) this.$replacement.focus()
          } else {
            this.$element[0].value = this.placeholderAttr
            this.$element.addClass(this.options.className)
            if (isActiveElement) this.setCaret(e)
          }
        }
      }
  
      // Set caret at the beginning of the input
    , setCaret: function (e) {
        if (e && !this.isHidden) {
          setCaretTo(this.$replacement[0], 0)
          e.preventDefault()
        }
      }
  
      // Make and return replacement element
    , makeReplacement: function () {
        // we can't use $.fn.clone because ie <= 8 doesn't allow type change
        var replacementAttributes =
          $.extend(
            getAttributes(this.$element[0])
          , { 'type': 'text'
            , 'value': this.placeholderAttr
            }
          )
  
        // replacement should not have input name
        delete replacementAttributes.name
  
        this.$replacement = $('<input>', replacementAttributes)
          .data('placeholder', this)
          .addClass(this.options.className)
  
        return this.$replacement;
      }
  
    }
  
  
    // Override jQuery val and prop hooks
    $.valHooks.input = $.valHooks.textarea = $.propHooks.value = {
      get: function (element) {
        var placeholder = $(element).data('placeholder')
        return placeholder ? placeholder.val() : element.value;
      }
    , set: function (element, value) {
        var placeholder = $(element).data('placeholder')
        return placeholder ? placeholder.val(value) : element.value = value;
      }
    }
  
  
    // Plugin definition
    $.fn.placeholder = function (option) {
      return this.each(function () {
        var $this = $(this)
          , data = $this.data('placeholder')
          , options = $.extend({}, $.fn.placeholder.defaults, typeof option === 'object' && option)
  
        if (!data && $this.is('[placeholder]') && (options.force ||
            !isInputSupported && $this.is('input') ||
            !isTextareaSupported && $this.is('textarea'))) {
          $this.data('placeholder', data = new Placeholder(this, options))
        }
  
        if (data && typeof option === 'string') data[option]()
      })
    }
    $.fn.placeholder.defaults = {
      force: false
    , className: 'placeholder'
    }
    $.fn.placeholder.Constructor = Placeholder
  
  
    // Events
    $(document).on('submit.placeholder', 'form', function () {
      // Clear the placeholder values so they don't get submitted
      $placeholders.placeholder('hide')
      // And then restore them back
      setTimeout(function () { $placeholders.placeholder('show') }, 10)
    })
    $(window).on('beforeunload.placeholder', function () {
      // Clear placeholders upon page reload
      $placeholders.placeholder('hide')
    })
  
    return Placeholder
  
  }));