src/derails/action_dispatch/system_testing/test_helpers/screenshot_helper.rb
# frozen_string_literal: true

# :markup: markdown

module ActionDispatch
  module SystemTesting
    module TestHelpers
      # Screenshot helper for system testing.
      module ScreenshotHelper
        # Takes a screenshot of the current page in the browser.
        #
        # `take_screenshot` can be used at any point in your system tests to take a
        # screenshot of the current state. This can be useful for debugging or
        # automating visual testing. You can take multiple screenshots per test to
        # investigate changes at different points during your test. These will be named
        # with a sequential prefix (or 'failed' for failing tests)
        #
        # The default screenshots directory is `tmp/screenshots` but you can set a
        # different one with `Capybara.save_path`
        #
        # You can use the `html` argument or set the
        # `RAILS_SYSTEM_TESTING_SCREENSHOT_HTML` environment variable to save the HTML
        # from the page that is being screenshotted so you can investigate the elements
        # on the page at the time of the screenshot
        #
        # You can use the `screenshot` argument or set the
        # `RAILS_SYSTEM_TESTING_SCREENSHOT` environment variable to control the output.
        # Possible values are:
        #     `simple` (default)
        # :       Only displays the screenshot path. This is the default value.
        #
        #     `inline`
        # :       Display the screenshot in the terminal using the iTerm image protocol
        #         (https://iterm2.com/documentation-images.html).
        #
        #     `artifact`
        # :       Display the screenshot in the terminal, using the terminal artifact
        #         format (https://buildkite.github.io/terminal-to-html/inline-images/).
        #
        #
        def take_screenshot(html: false, screenshot: nil)
          showing_html = html || html_from_env?

          increment_unique
          save_html if showing_html
          save_image
          show display_image(html: showing_html, screenshot_output: screenshot)
        end

        # Takes a screenshot of the current page in the browser if the test failed.
        #
        # `take_failed_screenshot` is called during system test teardown.
        def take_failed_screenshot
          return unless failed? && supports_screenshot? && Capybara::Session.instance_created?

          take_screenshot
          metadata[:failure_screenshot_path] = relative_image_path if Minitest::Runnable.method_defined?(:metadata)
        end

        private
          attr_accessor :_screenshot_counter

          def html_from_env?
            ENV["RAILS_SYSTEM_TESTING_SCREENSHOT_HTML"] == "1"
          end

          def increment_unique
            @_screenshot_counter ||= 0
            @_screenshot_counter += 1
          end

          def unique
            failed? ? "failures" : (_screenshot_counter || 0).to_s
          end

          def image_name
            sanitized_method_name = method_name.gsub(/[^\w]+/, "-")
            name = "#{unique}_#{sanitized_method_name}"
            name[0...225]
          end

          def image_path
            absolute_image_path.to_s
          end

          def html_path
            absolute_html_path.to_s
          end

          def absolute_path
            Rails.root.join(screenshots_dir, image_name)
          end

          def screenshots_dir
            Capybara.save_path.presence || "tmp/screenshots"
          end

          def absolute_image_path
            "#{absolute_path}.png"
          end

          def relative_image_path
            "#{absolute_path.relative_path_from(Rails.root)}.png"
          end

          def absolute_html_path
            "#{absolute_path}.html"
          end

          # rubocop:disable Lint/Debugger
          def save_html
            page.save_page(absolute_html_path)
          end

          def save_image
            page.save_screenshot(absolute_image_path)
          end
          # rubocop:enable Lint/Debugger

          def output_type
            # Environment variables have priority
            output_type = ENV["RAILS_SYSTEM_TESTING_SCREENSHOT"] || ENV["CAPYBARA_INLINE_SCREENSHOT"]

            # Default to outputting a path to the screenshot
            output_type ||= "simple"

            output_type
          end

          def show(img)
            puts img
          end

          def display_image(html:, screenshot_output:)
            message = +"[Screenshot Image]: #{image_path} \n"
            message << +"[Screenshot HTML]: #{html_path} \n" if html

            case screenshot_output || output_type
            when "artifact"
              message << "\e]1338;url=artifact://#{absolute_image_path}\a\n"
            when "inline"
              name = inline_base64(File.basename(absolute_image_path))
              image = inline_base64(File.read(absolute_image_path))
              message << "\e]1337;File=name=#{name};height=400px;inline=1:#{image}\a\n"
            end

            message
          end

          def inline_base64(path)
            Base64.strict_encode64(path)
          end

          def failed?
            !passed? && !skipped?
          end

          def supports_screenshot?
            Capybara.current_driver != :rack_test
          end
      end
    end
  end
end
