#!/usr/bin/env ruby
require_relative 'utils.rb'

class BgpRegistry < Registry
  def update_configs
    template_name = data["host"]["bird"]["template_name"] rescue nil
    template_name or die "bird.template_name not set for this host"

    peers = data["network"]
    v4_templ, v6_templ = generate_configs(template_name, peers)

    bird_path = Pathname.new(File.expand_path("../../bird/", __FILE__))
    atomic_write(bird_path.join("peers.conf"), v4_templ)
    atomic_write(bird_path.join("peers6.conf"), v6_templ)
  end

  def generate_configs(template_name, peers)
    template_path = Pathname.new(File.expand_path("../../templates", __FILE__))
    template = Template.new(template_path.join("bird.conf.erb"))
    v4_peers = collect_bgp_peers(peers, template_name, :v4)
    v6_peers = collect_bgp_peers(peers, template_name, :v6)
    return template.render(peers: v4_peers), template.render(peers: v6_peers)
  end

  private
  def collect_bgp_peers(peers, template_name, proto)
    peers.map do |name, peer|
      if peer["as"] && peer["#{proto}_tunnel"]
        context = {
          name: name,
          template: template_name,
          tunnel_ip: peer["#{proto}_tunnel"],
          as: peer["as"]
        }
        TemplateContext.new(context)
      end
    end.compact!
  end
end