# 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
        Kernel.spawn(
          {
            'NODE_ENV' => 'development',
            'BLUEBIRD_DEBUG' => '0',
            'BLUEBIRD_LONG_STACK_TRACES' => '0',
          },
          command,
          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

      def command
        command_list = [
          sewing_kit_bin,
          'dev',
          '--logLevel',
          log_level,
        ].concat(options)

        if debug_mode?
          command_list.push(['--debug'])
        end

        command_list.join(' ')
      end

      def sewing_kit_bin
        heap_size = SewingKit.configuration.development_options[:heap]
        heap_config = if heap_size
          "node --max-old-space-size=#{heap_size} "
        end

        bin = "#{heap_config}#{SewingKit.configuration.dev_server_sewing_kit_bin}"
        raise NodeSewingKitNotInstalled unless File.exist?(bin)
        bin
      end

      def log_level
        if SewingKit.configuration.log_level == :inherit
          log_level_from_rails
        else
          SewingKit.configuration.log_level.to_s
        end
      end

      def options
        development_options = SewingKit.configuration.development_options || {}
        focus = focus_sections

        development_options
          .reject { |key| key == :heap }
          .map { |key, value| ["--#{key.to_s.tr('_', '-')}", value] }.flatten + focus.flatten
      end

      def log_level_from_rails
        case Rails.logger.level
        when 0
          :debug
        when 1
          :info
        when 2
          :warn
        else
          :error
        end
      end

      def debug_mode?
        !ENV['SK_DEBUG'].nil?
      end

      def focus_sections
        return [] if ENV['SK_FOCUS'].nil?

        ENV['SK_FOCUS']
          .split(',')
          .map { |section| ["--focus", section] }
      end
    end
  end
end