Rails 3 custom form builder implementing a simple color picker based on JQuery and CaryonBox plugin

README

     INSTALLATION

the rails application must have support for JQuery
get JQuery.Crayonbox.js at http://gelform.com/crayonbox-jquery-plugin/

add the plugin JQuery.Crayonbox.js to /public/javascript folder 
add the crayonbox css to /public/stylesheets folder
add color_picker_form_builder.rb to the /lib folder

add to the view or layout file:
   <%= javascript_include_tag "jquery.crayonbox.js" %>
   <%= stylesheet_link_tag jquery.crayonbox.css %>

Use in form builder
   - builder.color_picker :color
   - builder.color_picker :color, :available => [ "#ff6600", "#785f4b", "#56bb98", "#786575", "#000000" ]

color_picker_form_builder.rb

class ColorPickerFormBuilder < ActionView::Helpers::FormBuilder    
  def color_picker(method, options={})
    
    default_colors = [ "#C0C0C0", "#FF6347", "#FFA500", "#FFFF00", "#7FFF00", "#00BFFF", "#C71585" ].freeze
    
    selected_color = @object.send(method)
    
    options[:available] ||= default_colors
    sanitized_object_name ||= @object_name.gsub(/\]\[|[^-a-zA-Z0-9:.]/, "_").sub(/_$/, "")
    sanitized_method_name ||= method.to_s.sub(/\?$/,"")
    c_picker = "<input type=\"hidden\" id=\"id_#{sanitized_object_name}_#{sanitized_method_name}\" name=\"#{@object_name.to_s}[#{method.to_s}]\"/>"
    c_picker << "<script type=\"text/javascript\">"
    c_picker <<   "$('#id_#{sanitized_object_name}_#{sanitized_method_name}').crayonbox("
    c_picker <<     "{" 
    c_picker <<       "colors: new Array(#{options[:available].to_s.gsub(/^\[|\]$/, "")})"
    c_picker <<       ",selected: '#{selected_color}'" if selected_color 
    c_picker <<     "}"
    c_picker <<   "); "
    c_picker << "</script>"
    c_picker.html_safe
  end
end