# frozen_string_literal: true

require 'googleauth'
require 'googleauth/stores/file_token_store'

module Faculty
  module Google
    module Auth
      # Class for handing OAuth logins in local development instances
      class OAuth
        def initialize(path: Dir.pwd, scopes: [], user_id: 'default')
          @path = path
          @scopes = scopes
          @user_id = user_id
        end

        def authorization
          credentials = authorizer.get_credentials(@user_id)
          raise 'No Credentials. Check `rake` for a command to setup OAuth2.' if credentials.nil? && !$stdout.isatty

          credentials = fetch_credentials if credentials.nil?
          credentials
        end

        BASE_URL = 'http://localhost'

        private

        def authorizer
          @authorizer ||= begin
            FileUtils.mkdir_p(File.dirname(credentials_path))
            client_id = ::Google::Auth::ClientId.from_file(client_secrets_path)
            token_store = ::Google::Auth::Stores::FileTokenStore.new(file: credentials_path)
            ::Google::Auth::UserAuthorizer.new(client_id, @scopes, token_store)
          end
        end

        def client_secrets_path
          "#{@path}/google-client-secrets.json"
        end

        def credentials_path
          "#{@path}/google-oauth.yaml"
        end

        def fetch_credentials
          url = authorizer.get_authorization_url(base_url: BASE_URL)
          puts "Open this URL in a browser and enter the auth code back here:\n\n#{url}\n\nCode:"
          code = $stdin.gets.chomp
          authorizer.get_and_store_credentials_from_code(user_id: @user_id, code:, base_url: BASE_URL)
        end
      end
    end
  end
end