# frozen_string_literal: true

require 'English'

module SewingKit
  module Webpack
    class Dev
      class NodeSewingKitNotInstalled < StandardError
        def initialize
          super(
            "sewing-kit is not installed.  " \
            "Try `yarn add @shopify/sewing-kit`"
          )
        end
      end

      attr_accessor :pid

      def start
        @pid = spawn
        at_exit { handle_exit }
        detach
      end

      private

      def spawn
        sewing_kit_bin = 'node_modules/.bin/sewing-kit'
        raise NodeSewingKitNotInstalled unless File.exist?(sewing_kit_bin)

        Kernel.spawn(
          {
            'NODE_ENV' => 'development',
            'BLUEBIRD_DEBUG' => '0',
            'BLUEBIRD_LONG_STACK_TRACES' => '0',
          },
          sewing_kit_bin,
          'dev',
          chdir: Rails.root.to_s,
          out: $stdout,
          err: $stderr,
        ) || exit(1)
      end

      def handle_exit
        return if $ERROR_INFO.nil?
        Process.kill 'SIGTERM', pid
      rescue Errno::ESRCH
        nil
      end

      def detach
        Process.detach pid
      end
    end
  end
end