# frozen_string_literal: true

require 'hs/loaders/xml_parser'

module HS
  module CourseLoader
    include HS::XMLParser

    KNOWN_LOADERS = %i[title chapters].freeze

    def load_course(xml, &block)
      create_course(parse_xml(xml), &block)
    end

    private

    def create_course(data, &block)
      course = HS::Course.new(data.slice(:slug))
      data[:_children].each { |child| load_a_part(course, child, &block) }
      course
    end

    def load_a_part(course, child, &block)
      return unless KNOWN_LOADERS.include?(child[:_name])
      send("load_#{child[:_name]}", course, child, &block)
    end

    def load_title(course, child)
      course.title = get_text(child)
    end

    def load_chapters(course, child)
      return unless block_given?
      files = child[:_children].map { |c| c[:file] }.compact
      files.each { |file| yield course, file }
    end
  end
end