Rails service objects for business logic

module Posts
  class CreateService
    def initialize(author:, params:)
      @author = author
      @params = params
    end

    def call
      ActiveRecord::Base.transaction do
        create_post
        attach_images if @params[:images].present?
        notify_followers
        schedule_publication if @post.scheduled?

        Result.success(post: @post)
      end
    rescue ActiveRecord::RecordInvalid => e
      Result.failure(errors: e.record.errors.full_messages)
    rescue => e
      Rails.logger.error "Failed to create post: #{e.message}"
      Result.failure(errors: ['An unexpected error occurred'])
    end

    private

    def create_post
      @post = @author.posts.create!(
        title: @params[:title],
        body: @params[:body],
        status: @params[:status] || 'draft'
      )
    end

    def attach_images
      @params[:images].each do |blob_id|
        @post.images.attach(blob_id)
      end
    end

    def notify_followers
      return unless @post.published?

      NotifyFollowersJob.perform_later(@post.id)
    end

    def schedule_publication
      PublishPostJob.set(wait_until: @post.publish_at).perform_later(@post.id)
    end
  end

  class Result
    attr_reader :data, :errors

    def self.success(data = {})
      new(success: true, data: data)
    end

    def self.failure(errors:)
      new(success: false, errors: errors)
    end

    def initialize(success:, data: {}, errors: [])
      @success = success
      @data = data
      @errors = errors
    end

    def success?
      @success
    end

    def failure?
      !@success
    end
  end
end