MatchLiveTv/backend/app/services/streams/dns_providers/hetzner.rb

# frozen_string_literal: true

require "faraday"
require "cgi"

module Streams
  module DnsProviders
    # Hetzner Cloud DNS (Console) — zone mltv-stream.net.
    #
    # ENV:
    #   HCLOUD_TOKEN (stesso del Cloud)
    #   STREAM_DNS_ZONE (default mltv-stream.net)
    #   STREAM_DNS_TTL (default 60)
    class Hetzner < Base
      # Trailing slash obbligatorio: path assoluti altrimenti droppano /v1.
      API = "https://api.hetzner.cloud/v1/"

      def initialize(token: ENV.fetch("HCLOUD_TOKEN"), zone: nil, conn: nil)
        @token = token
        @zone = zone || ENV.fetch("STREAM_DNS_ZONE", "mltv-stream.net")
        @ttl = ENV.fetch("STREAM_DNS_TTL", "60").to_i
        @conn = conn
      end

      def upsert_a(name, ip)
        rr_name = relative_name(name)
        delete_a(name)
        post("zones/#{CGI.escape(@zone)}/rrsets", {
          name: rr_name,
          type: "A",
          ttl: @ttl,
          records: [{ value: ip.to_s, comment: "matchlivetv stream-node" }],
          labels: { "matchlivetv" => "true", "role" => "stream-node" }
        })
        true
      end

      def delete_a(name)
        rr_name = relative_name(name)
        encoded = CGI.escape(rr_name)
        response = conn.delete("zones/#{CGI.escape(@zone)}/rrsets/#{encoded}/A") do |req|
          req.headers.update(auth_headers)
        end
        return true if response.status == 404 || response.status == 204 || response.success?

        raise Error, "Hetzner DNS API #{response.status}: #{response.body.inspect}"
      end

      def resolve(name)
        rr_name = relative_name(name)
        data = get("zones/#{CGI.escape(@zone)}/rrsets", name: rr_name, type: "A")
        rrset = Array(data["rrsets"]).first
        Array(rrset&.dig("records")).first&.dig("value")
      rescue Error
        nil
      end

      private

      def relative_name(name)
        host = name.to_s.strip.downcase.delete_suffix(".")
        suffix = ".#{@zone}"
        return "@" if host == @zone
        return host.delete_suffix(suffix) if host.end_with?(suffix)

        host
      end

      def conn
        @conn ||= Faraday.new(url: API) do |f|
          f.request :json
          f.response :json, content_type: /\bjson$/
          f.adapter Faraday.default_adapter
        end
      end

      def auth_headers
        { "Authorization" => "Bearer #{@token}" }
      end

      def get(path, params = {})
        response = conn.get(path) do |req|
          req.headers.update(auth_headers)
          req.params.update(params)
        end
        unwrap!(response)
      end

      def post(path, body)
        response = conn.post(path) do |req|
          req.headers.update(auth_headers)
          req.body = body
        end
        unwrap!(response)
      end

      def unwrap!(response)
        unless response.success?
          raise Error, "Hetzner DNS API #{response.status}: #{response.body.inspect}"
        end

        response.body.is_a?(Hash) ? response.body : {}
      end
    end
  end
end