# frozen_string_literal: true

module Karafka
  module Contracts
    # Contract for validating correctness of the server cli command options.
    class ServerCliOptions < Base
      configure do |config|
        config.error_messages = YAML.safe_load(
          File.read(
            File.join(Karafka.gem_root, 'config', 'locales', 'errors.yml')
          )
        ).fetch('en').fetch('validations').fetch('server_cli_options')
      end

      optional(:consumer_groups) { |cg| cg.is_a?(Array) }
      optional(:subscription_groups) { |sg| sg.is_a?(Array) }
      optional(:topics) { |topics| topics.is_a?(Array) }

      virtual do |data, errors|
        next unless errors.empty?
        next unless data.key?(:consumer_groups)

        value = data.fetch(:consumer_groups)

        # If there were no consumer_groups declared in the server cli, it means that we will
        # run all of them and no need to validate them here at all
        next if value.empty?
        next if (value - Karafka::App.consumer_groups.map(&:name)).empty?

        # Found unknown consumer groups
        [[%i[consumer_groups], :consumer_groups_inclusion]]
      end

      virtual do |data, errors|
        next unless errors.empty?
        next unless data.key?(:subscription_groups)

        value = data.fetch(:subscription_groups)

        # If there were no subscription_groups declared in the server cli, it means that we will
        # run all of them and no need to validate them here at all
        next if value.empty?

        subscription_groups = Karafka::App
                              .consumer_groups
                              .map(&:subscription_groups)
                              .flatten
                              .map(&:name)

        next if (value - subscription_groups).empty?

        # Found unknown subscription groups
        [[%i[subscription_groups], :subscription_groups_inclusion]]
      end

      virtual do |data, errors|
        next unless errors.empty?
        next unless data.key?(:topics)

        value = data.fetch(:topics)

        # If there were no topics declared in the server cli, it means that we will
        # run all of them and no need to validate them here at all
        next if value.empty?

        topics = Karafka::App
                 .consumer_groups
                 .map(&:subscription_groups)
                 .flatten
                 .map(&:topics)
                 .map { |gtopics| gtopics.map(&:name) }
                 .flatten

        next if (value - topics).empty?

        # Found unknown topics
        [[%i[topics], :topics_inclusion]]
      end

      # Makes sure we have anything to subscribe to when we start the server
      virtual do |_, errors|
        next unless errors.empty?
        next unless Karafka::App.subscription_groups.empty?

        [[%i[topics], :topics_missing]]
      end
    end
  end
end