require "open-uri"
require "singleton"
require "timeout"
require "tempfile"

module RSpec
  class VaultServer
    include Singleton

    def self.method_missing(m, *args, &block)
      self.instance.public_send(m, *args, &block)
    end

    attr_reader :token

    def initialize
      io = Tempfile.new("vault-server")
      pid = Process.spawn({}, "vault server -dev", out: io.to_i, err: io.to_i)

      at_exit do
        Process.kill("INT", pid)
        Process.waitpid2(pid)

        io.close
        io.unlink
      end

      wait_for_ready do
        output = ""

        while
          io.rewind
          output = io.read
          break if !output.empty?
        end

        if output.match(/Root Token: (.+)/)
          @token = $1.strip
        else
          raise "Vault did not return a token!"
        end
      end
    end

    def address
      "http://127.0.0.1:8200"
    end

    def wait_for_ready(&block)
      Timeout.timeout(5) do
        while
          begin
            open(address)
          rescue SocketError, Errno::ECONNREFUSED, EOFError
          rescue OpenURI::HTTPError => e
            break if e.message =~ /404/
          end

          sleep(0.25)
        end
      end

      yield
    rescue Timeout::Error
      raise "Vault did not start in 5 seconds!"
    end
  end
end