require 'active_support/core_ext/object/to_param'

class Object
  # Converts an object into a string suitable for use as a URL query string, using the given <tt>key</tt> as the
  # param name.
  #
  # Note: This method is defined as a default implementation for all Objects for Hash#to_query to work.
  def to_query(key)
    require 'cgi' unless defined?(CGI) && defined?(CGI::escape)
    "#{CGI.escape(key.to_param)}=#{CGI.escape(to_param.to_s)}"
  end
end

class Array
  # Converts an array into a string suitable for use as a URL query string,
  # using the given +key+ as the param name.
  #
  #   ['Rails', 'coding'].to_query('hobbies') # => "hobbies%5B%5D=Rails&hobbies%5B%5D=coding"
  def to_query(key)
    prefix = "#{key}[]"

    if empty?
      nil.to_query(prefix)
    else
      collect { |value| value.to_query(prefix) }.join '&'
    end
  end
end

class Hash
  alias_method :to_query, :to_param
end
