module Admin::Resources::FormHelper

  def build_form(fields, form)
    String.new.tap do |html|
      fields.each do |key, value|
        value = :template if (template = @resource.typus_template(key))
        html << case value
                when :belongs_to
                  typus_belongs_to_field(key, form)
                when :tree
                  typus_tree_field(key, form)
                when :boolean, :date, :datetime, :text, :time, :password, :selector, :dragonfly, :paperclip
                  typus_template_field(key, value, form)
                when :template
                  typus_template_field(key, template, form)
                when :has_and_belongs_to_many
                  typus_has_and_belongs_to_many_field(key, form)
                else
                  typus_template_field(key, :string, form)
                end
      end
    end.html_safe
  end

  def typus_template_field(attribute, template, form)
    options = { :start_year => @resource.typus_options_for(:start_year),
                :end_year => @resource.typus_options_for(:end_year),
                :minute_step => @resource.typus_options_for(:minute_step),
                :disabled => attribute_disabled?(attribute),
                :include_blank => true }

    html_options = attribute_disabled?(attribute) ? { :disabled => 'disabled' } : {}

    label_text = @resource.human_attribute_name(attribute)

    if options[:disabled] == true
      label_text += "<small>#{Typus::I18n.t("Read only")}</small>"
    end

    locals = { :resource => @resource,
               :attribute => attribute,
               :attribute_id => "#{@resource.table_name}_#{attribute}",
               :options => options,
               :html_options => html_options,
               :form => form,
               :label_text => label_text.html_safe }

    render "admin/templates/#{template}", locals
  end

  def attribute_disabled?(attribute)
    if protected_attributes = @resource._protected_attributes
      protected_attributes[current_role].include?(attribute)
    end
  end

  def build_save_options
    save_options_for_user_class || save_options_for_headless_mode || save_options
  end

  def save_options
    options = {}
    options["_addanother"] = "Save and add another"
    if admin_user.can?('edit', @resource.model_name)
      options["_continue"] = "Save and continue editing"
    end
    options["_save"] = "Save"
    options
  end

  def save_options_for_headless_mode
    return unless headless_mode?
    { "_continue" => "Save" }
  end

  def save_options_for_user_class
    return unless !defined?(Typus.user_class) && Typus.user_class == @resource && admin_user.is_not_root?
    { "_continue" => "Save and continue editing" }
  end

end