gem "catch_box", "~> 0.1.0"

require "catch_box/fanout"

class Delivered
  def initialize(logger: Logger.new)
    @logger = logger
  end

  def call(payload)
    @logger.info(payload)
  end
end

class Fanout
  extend ::CatchBox::Fanout

  event "event-data.event"

  auth do |payload, env|
    # https://documentation.mailgun.com/en/latest/user_manual.html#webhooks
    payload["signature"]["signature"] == \
      ::OpenSSL::HMAC.hexdigest(
        ::OpenSSL::Digest::SHA256.new,
        ENV["MAILGUN_API_KEY"],
        [payload["signature"]["timestamp"], payload["signature"]["token"]].join
      )
  end

  on "delivered", Delivered.new

  all do |payload|
    ::Logger.new(::STDOUT).info(payload)
  end
end

require "sinatra/base"
require "catch_box/middleware"

class Application < Sinatra::Base
  use ::CatchBox::Middleware, fanout: Fanout, endpoint: "/mailgun"

  get "/" do
    "index"
  end
end