#!/usr/bin/env ruby

require 'date'
require 'yaml'
require 'bundler/inline'

gemfile do
  source 'https://rubygems.org'
  gem 'builder'
end

class Feed
  attr_reader :catalogue

  def initialize(catalogue)
    @catalogue = catalogue
  end

  def to_xml
    builder = Builder::XmlMarkup.new(indent: 2)
    builder.instruct! :xml, version: "1.0", encoding: "UTF-8"
    builder.rss(version: '2.0', 'xmlns:itunes' => "http://www.itunes.com/dtds/podcast-1.0.dtd", "xmlns:atom" => "http://www.w3.org/2005/Atom") do
      builder.channel do
        builder.atom :link, rel: 'self', type: 'application/atom+xml', href: "#{catalogue[:url]}/feed.rss", title: catalogue[:title]
        builder.title catalogue[:title]
        builder.link catalogue[:url]
        builder.language catalogue[:language]
        builder.copyright catalogue[:copyright]
        builder.itunes :subtitle, catalogue[:subtitle]
        builder.itunes :author, catalogue[:author]
        builder.itunes :summary, catalogue[:summary]
        builder.description catalogue[:description]
        builder.itunes :owner do
          builder.itunes :name, catalogue[:author]
          builder.itunes :email, catalogue[:email]
        end
        builder.itunes :image, href: catalogue[:image]
        builder.itunes :category, text: "Technology"
        builder.itunes :explicit, "no"
        catalogue[:episodes].each do |episode|
          builder.item do
            builder.title episode[:name]
            builder.itunes :author, episode[:author]
            builder.itunes :subtitle, episode[:subtitle]
            builder.itunes :summary do
              builder.cdata! episode[:summary]
            end
            builder.itunes :image, href: catalogue[:image]
            builder.enclosure length: episode[:mp3_size_bytes], type: episode[:mime_type], url: episode[:mp3_url]
            builder.guid episode[:permalink]
            builder.pubDate episode[:date].rfc822
            builder.itunes :duration, episode[:duration]
            builder.itunes :explicit, 'no'
          end
        end
      end
    end
    builder.target!
  end
end

data = YAML.safe_load(
  IO.read('episodes.yml'),
  permitted_classes: [Date],
  symbolize_names: true
)
puts Feed.new(data).to_xml