module ActiveAdmin::ViewHelpers::DisplayHelper

def association_methods_for(resource) 

def association_methods_for(resource)
  return [] unless resource.class.respond_to? :reflect_on_all_associations
  resource.class.reflect_on_all_associations.map(&:name)
end

def boolean_attr?(resource, attr, value) 

def boolean_attr?(resource, attr, value)
  case value
  when TrueClass, FalseClass
    true
  else
    if resource.class.respond_to? :columns_hash
      column = resource.class.columns_hash[attr.to_s] and column.type == :boolean
    end
  end
end

def display_name(resource)

See the setting in `application.rb` for the list of methods and their priority.
Attempts to call any known display name methods on the resource. 
def display_name(resource)
  ERB::Util.html_escape(render_in_context(resource, display_name_method_for(resource))) unless resource.nil?
end

def display_name_method_for(resource)

If no methods are available and we're about to use the Kernel's `to_s`, provide our own.
To prevent conflicts, we exclude any methods that happen to be associations.
Looks up and caches the first available display name method. 
def display_name_method_for(resource)
  @@display_name_methods_cache ||= {}
  @@display_name_methods_cache[resource.class] ||= begin
    methods = active_admin_application.display_name_methods - association_methods_for(resource)
    method = methods.detect { |method| resource.respond_to? method }
    if method != :to_s || resource.method(method).source_location
      method
    else
      DISPLAY_NAME_FALLBACK
    end
  end
end

def find_value(resource, attr) 

def find_value(resource, attr)
  if attr.is_a? Proc
    attr.call resource
  elsif resource.respond_to? attr
    resource.public_send attr
  elsif resource.respond_to? :[]
    resource[attr]
  end
end

def format_attribute(resource, attr) 

def format_attribute(resource, attr)
  value = find_value resource, attr
  if value.is_a?(Arbre::Element)
    value
  elsif boolean_attr?(resource, attr, value)
    Arbre::Context.new { status_tag value }
  else
    pretty_format value
  end
end

def format_collection(collection) 

def format_collection(collection)
  safe_join(collection.map { |item| pretty_format(item) }, ", ")
end

def pretty_format(object)

Attempts to create a human-readable string for any object 
def pretty_format(object)
  case object
  when String, Numeric, Symbol, Arbre::Element
    object.to_s
  when Date, Time
    I18n.localize object, format: active_admin_application.localize_format
  when Array
    format_collection(object)
  else
    if defined?(::ActiveRecord) && object.is_a?(ActiveRecord::Base) ||
       defined?(::Mongoid) && object.class.include?(Mongoid::Document)
      auto_link object
    elsif defined?(::ActiveRecord) && object.is_a?(ActiveRecord::Relation)
      format_collection(object)
    else
      display_name object
    end
  end
end