conver_date_params_to_string.rb

# This code just takes multiparamter inputs from a form and strings them together to 
# create dash separated date string.  The purpose behind this is because sometimes if
# a user doesn't fill in all the date drop downs in a form, you might get an invalid date
# The folowing code was repurposed from ActiveRecord::Base from a few of the mutliparamter 
# assignment methods

module ConverDateParamsToString
  
  def convert_date_params_to_string!(params, date_attr_name)
    date_params = params.reject {| key, value | !(key =~ /^#{date_attr_name}/) }
    params = params.reject {| key, value | (key =~ /^#{date_attr_name}/) }
    date_attributes=[]
    date_params.each do |date_param|
      name, value = date_param
      date_attributes << [name.scan(/\(([0-9]*).*\)/).first.first, value]
    end
    params[date_attr_name] = date_attributes.sort_by{|x| x.first}.collect{|x| x[1]}.join("-")
  end

end


class ControllerMock
  include ConverDateParamsToString
  
  def params 
    {
      "happy" => "joy",
      "date(3i)" => "20",
      "date(2i)" => "1",
      "date(1i)" => "2003"
    }
  end
end

controller = ControllerMock.new

puts controller.convert_date_params_to_string!(controller.params, "date")