html5 multiple file uploader js

pet_form.html.haml

.control-group.required.upload-photos
    = f.label 'Upload files', required: false
    .controls
      .file-upload-wrapper
        = link_to '#', class: 'file-upload red-btn' do
          %i.icons.upload
          Upload
        = f.input :attachment,
          as: :file,
          wrapper_html: { class: 'hidden-upload' },
          input_html: { multiple: 'multiple' }
        .file-text
          .file
          = link_to 'Delete', '#', class: 'red delete-upload-file'
      .file-upload-wrapper.frame-to-copy.hidden
        = link_to '#', class: 'file-upload red-btn' do
          %i.icons.upload
          Upload
        = f.input :attachment,
          as: :file,
          wrapper_html: { class: 'hidden-upload' },
          input_html: { multiple: 'multiple' }
        .file-text
          .file
          = link_to 'Delete', '#', class: 'red delete-upload-file'

ppm.js.coffee

# pet creation photo uploader
  $('.add-a-pet .upload-photos a.file-upload').on('click', (e)->
    e.preventDefault()
    clicked = $(this)
    parent_wrapper = clicked.closest('.file-upload-wrapper')
    hidden_upload = parent_wrapper.find('.hidden-upload').find('input')
    file_text = parent_wrapper.find('.file-text')
    delete_file = parent_wrapper.find('.delete-upload-file')

    hidden_upload.trigger('click')

    hidden_upload.change ->
      if Modernizr.input.multiple
        $uploads = this.files
        file_val = '<p>You uploaded ' + this.files.length + ' files: <br/><br/>'
        # loop thru multiple files
        for f in $uploads
          file_val = file_val + f.name + ',<br/> '
        if this.files.length > 6
          file_val = file_val + '<br/> Only the first 6 will be uploaded'
        else
          parent = parent_wrapper.closest('.controls')
          cloned = parent.find('.frame-to-copy').clone()
          parent_wrapper.after(cloned.removeClass('frame-to-copy').removeClass('hidden'))
          file_val = file_val + '</p>'
      else
        file_val = $(this).val()
        file_val = if file_val.length then file_val.split('\\').pop() else ''
      file_text.find('.file').html(file_val)
      file_text.show()
      clicked.hide()

      # if html5 multiple attribute not supported
      if not Modernizr.input.multiple
        # count num of uploaders, max = 6, add new upload button
        parent = parent_wrapper.closest('.controls')
        uploader_count = parent.find('.file-upload-wrapper').not('.frame-to-copy').length
        if uploader_count < 6
          cloned = parent.find('.frame-to-copy').clone()
          parent_wrapper.after(cloned.removeClass('frame-to-copy').removeClass('hidden'))

    delete_file.on('click', (e) ->
      e.preventDefault()
      file_text.hide()
      clicked.show()
      alert('This will remove said uploaded file')
    )
  )