require 'fiona7/attribute_readers/binary_as_binary'
require 'fiona7/attribute_readers/binary_as_linklist'
require 'fiona7/attribute_readers/date_as_date'
require 'fiona7/attribute_readers/html_as_html'
require 'fiona7/attribute_readers/link_as_linklist'
require 'fiona7/attribute_readers/linklist_as_linklist'
require 'fiona7/attribute_readers/multienum_as_multienum'
require 'fiona7/attribute_readers/multienum_as_text'
require 'fiona7/attribute_readers/number_as_string'
require 'fiona7/attribute_readers/reference_as_linklist'
require 'fiona7/attribute_readers/reference_as_string'
require 'fiona7/attribute_readers/referencelist_as_linklist'
require 'fiona7/attribute_readers/referencelist_as_text'
require 'fiona7/attribute_readers/simple'
require 'fiona7/attribute_readers/stringlist_as_text'
require 'fiona7/attribute_readers/widgetlist_as_linklist'

module Fiona7
  module AttributeReaders
    class Factory
      def initialize(obj, type_def, widget_resolver)
        self.obj             = obj
        self.type_def        = type_def
        self.widget_resolver = widget_resolver
      end

      def call(attribute, virtual_type, real_type)
        virtual = virtual_type.to_sym
        real    = real_type.to_sym

        worker = case [virtual, real]
                 when [:linklist, :linklist]
                   Fiona7::AttributeReaders::LinklistAsLinklist
                 when [:link, :linklist]
                   Fiona7::AttributeReaders::LinkAsLinklist
                 when [:reference, :linklist]
                   Fiona7::AttributeReaders::ReferenceAsLinklist
                 when [:reference, :string], [:reference, :text]
                   Fiona7::AttributeReaders::ReferenceAsString
                 when [:referencelist, :linklist]
                   Fiona7::AttributeReaders::ReferencelistAsLinklist
                 when [:referencelist, :text], [:referencelist, :string]
                   Fiona7::AttributeReaders::ReferencelistAsText
                 when [:widgetlist, :linklist]
                   Fiona7::AttributeReaders::WidgetlistAsLinklist
                 when [:multienum, :text], [:multienum, :string]
                   Fiona7::AttributeReaders::MultienumAsText
                 when [:multienum, :multienum]
                   Fiona7::AttributeReaders::MultienumAsMultienum
                 when [:number, :string], [:number, :text]
                   Fiona7::AttributeReaders::NumberAsString
                 when [:html, :html]
                   Fiona7::AttributeReaders::HtmlAsHtml
                 when [:binary, :linklist]
                   Fiona7::AttributeReaders::BinaryAsLinklist
                 when [:binary, :binary]
                   Fiona7::AttributeReaders::BinaryAsBinary
                 when [:stringlist, :text], [:stringlist, :string]
                   Fiona7::AttributeReaders::StringlistAsText
                 when [:stringlist, :multienum]
                   Fiona7::AttributeReaders::Simple
                 when [:stringlist, :stringlist]
                   # NOTE: this is practically only used for "channels"
                   Fiona7::AttributeReaders::Simple
                 else
                   case virtual
                   when :text, :string, :enum, :markdown
                     Fiona7::AttributeReaders::Simple
                   when :date
                     Fiona7::AttributeReaders::DateAsDate
                   else
                     # It would perhaps be practical to raise this error here
                     # but also risky: broken configurations may surface
                     # (attributes which had their attribute types changed).
                     # This would break some pages
                     #
                     # raise(Fiona7::TypeSystemError.new("Unable to read #{attribute} in #{self.type_def.name} with typing #{virtual}:#{real}"))
                     #
                     # So instead, it is better to "lose" some information.
                     return nil
                   end
                 end

        worker.new(self.obj, attribute, self.widget_resolver)
      end

      protected
      attr_accessor :obj, :obj_class, :type_def, :widget_resolver
    end
  end
end