# frozen_string_literal: true

require "dry-transformer"
require "json"

module DjiMqttConnect
  module Thing::Product
    class OsdMarshal < MessageMarshal
      include Utils::MessageParsing

      # Make a copy of the raw data
      class AttributeTransformer < Dry::Transformer::Pipe
        import Dry::Transformer::Conditional
        import Dry::Transformer::HashTransformations

        define! do
          # Ensure there is a data element
          map_value "data", ->(data) { data || {} }

          # Create a backup for unsupported attributes
          copy_keys "data" => "_data"

          map_value "data" do
            # Rename the invalid (for Ruby) wireless link attributes
            guard ->(data) { data.key?("wireless_link") } do
              # Translate wireless_link 4g keys (from remote payload)
              map_value "wireless_link" do
                rename_keys "4g_freq_band" => "_4g_freq_band",
                  "4g_gnd_quality" => "_4g_gnd_quality",
                  "4g_link_state" => "_4g_link_state",
                  "4g_quality" => "_4g_quality",
                  "4g_uav_quality" => "_4g_uav_quality"
              end
            end
          end
        end
      end

      # Parse message from Device > Cloud Server
      def load(raw_message)
        parsed_message = parse_json(raw_message)

        message_data = parsed_message.fetch("data", {})

        message_class = if drone_osd_data_attributes.all? { |attribute| message_data.key?(attribute.to_s) }
          DroneOsdMessage
        elsif required_remote_osd_data_attributes.all? { |attribute| message_data.key?(attribute.to_s) } &&
            optional_remote_osd_data_attributes.any? { |attribute| message_data.key?(attribute.to_s) }
          RemoteOsdMessage
        elsif dock_osd_data_attributes.any? { |attribute| message_data.key?(attribute.to_s) }
          DockOsdMessage
        else
          OsdMessage
        end

        transformed_message = attribute_transformer.call(parsed_message)

        build_message(message_class, transformed_message)
      end

      private

      def attribute_transformer
        @attribute_transformer ||= AttributeTransformer.new
      end

      def dock_osd_data_attributes
        @dock_osd_data_attributes ||= DockOsdMessage::STABLE_DATA_ATTRIBUTES.map(&:to_s)
      end

      def drone_osd_data_attributes
        @drone_osd_data_attributes ||= DroneOsdMessage::STABLE_DATA_ATTRIBUTES.map(&:to_s)
      end

      def required_remote_osd_data_attributes
        @required_remote_osd_data_attributes ||= begin
          data_keys = DjiMqttConnect::Thing::Product::RemoteOsdMessage::Data.schema.keys
          data_keys.select(&:required?).map(&:name)
        end
      end

      def optional_remote_osd_data_attributes
        @optional_remote_osd_data_attributes ||= begin
          data_keys = DjiMqttConnect::Thing::Product::RemoteOsdMessage::Data.schema.keys
          data_keys.reject(&:required?).map(&:name)
        end
      end
    end
  end
end