# frozen_string_literal: true

module LicenseFinder
  class Yarn
    INCOMPATIBLE_PACKAGE_REGEX = /(?<name>[\w,\-]+)@(?<version>(\d+\.?)+)/.freeze
    PHANTOM_PACKAGE_REGEX = /workspace-aggregator-[a-zA-Z0-9]{8}-[a-zA-Z0-9]{4}-[a-zA-Z0-9]{4}-[a-zA-Z0-9]{4}-[a-zA-Z0-9]{12}/.freeze

    def possible_package_paths
      [project_path.join('yarn.lock')]
    end

    def prepare
      within_project_path do
        tool_box.install(tool: :nodejs, version: nodejs_version, env: default_env)
        shell.execute([
          :yarn, :install,
          '--ignore-engines', '--ignore-scripts',
          '--production'
        ], env: default_env, capture: false)
      end
    end

    def current_packages
      stdout, _stderr, status = within_project_path do
        shell.execute(list_licenses_command)
      end
      return [] unless status.success?

      stdout.each_line.flat_map do |line|
        dependencies_from(JSON.parse(line))
      end
    end

    private

    def list_licenses_command
      [
        :yarn,
        :licenses,
        :list,
        '--no-progress',
        '--json',
        '--production',
        '--cwd',
        project_path || Pathname.pwd
      ]
    end

    def install_path_for(name)
      if project_path
        project_path.join('node_modules', name)
      else
        Pathname.pwd.join('node_modules', name)
      end
    end

    def map_from(hash)
      build(
        hash['Name'],
        hash['Version'],
        spec_licenses: [hash['License']],
        install_path: install_path_for(hash['Name']).to_s,
        homepage: hash['VendorUrl']
      )
    end

    def dependencies_from(json)
      case json['type']
      when 'table'
        from_json_table(json)
      when 'info'
        from_json_info(json)
      else
        []
      end
    end

    def from_json_table(json)
      head = json['data']['head']
      json['data']['body'].map do |array|
        hash = Hash[head.zip(array)]
        map_from(hash) unless PHANTOM_PACKAGE_REGEX.match(hash['Name'])
      end.compact
    end

    def from_json_info(json)
      matches = json['data'].to_s.match(INCOMPATIBLE_PACKAGE_REGEX)
      return [] unless matches

      [build(matches['name'], matches['version'], spec_licenses: ['unknown'])]
    end

    def build(name, version, options = {})
      Dependency.new('Yarn', name, version, options.merge(detection_path: detected_package_path))
    end

    def default_env
      {
        'NPM_CONFIG_CAFILE' => ENV.fetch('NPM_CONFIG_CAFILE', shell.default_certificate_path).to_s
      }
    end

    def nodejs_version
      @nodejs_version ||= tool_box.version_of(:nodejs)
    end
  end
end