require 'socket'
require 'open4'

module RackCheck

class ServerManager
  include RackCheck::Helpers

  attr_reader :context, :ru_file

  def initialize(context, ru_file)
    @ru_file = ru_file
    @stop_var = Concurrent::MVar.new
    @context = context
  end

  def run
    Thread.new do
      begin
        with_environment(ru_file) do |dir|
          Dir.chdir(dir) do
            @pid, @in, @out, @err = Open4.popen4 context.app_server_command
            @stop_var.take
            Process.kill 'TERM', @pid
            Process.wait @pid
            @pid = nil
          end
        end
      rescue => e
        $stderr.puts "App server thread exited: #{e.message}\n#{e.backtrace.join("\n")}"
      end
    end

    port = wait_for_port

    "http://localhost:#{port}"
  end

  def stop
    @stop_var.put true
    while check_port
      sleep 0.1
    end
  end

  def errors
    @err&.read.strip
  end

  def output
    @out&.read.strip
  end

  private

  def wait_for_port
    time = Time.now
    while Time.now - time < context.startup_timeout && !check_port
      sleep 0.1
    end

    if !check_port
      Process.kill 'TERM', @pid if @pid
      raise "Application server did not start up in time"
    end

    context.app_server_port
  end

  def check_port
    TCPSocket.new('localhost', context.app_server_port).close
    true
  rescue
    false
  end
end
end