# frozen_string_literal: true

##
# Usage:
#
#   ConvenientService::Examples::Rails::Gemfile::Services::StripComments.result(content: "abc")
#
module ConvenientService
  module Examples
    module Rails
      class Gemfile
        module Services
          class StripComments
            include RailsService::Config

            attribute :content, :string

            validates :content, presence: true if ConvenientService::Dependencies.support_has_j_send_result_params_validations_using_active_model_validations?

            alias_method :content_with_comments, :content

            step Services::AssertNpmPackageAvailable, in: {name: -> { "strip-comments" }}
            step Services::RunShellCommand, in: {command: -> { "node -e '#{js_script}' #{file_with_comments.path} #{file_without_comments.path}" }}
            step :result, in: :file_without_comments, out: :content_without_comments

            def result
              success(data: {content_without_comments: file_without_comments.read})
            end

            ##
            # NOTE: When you have no time to do something well, delegate that task to someone who already works with it all the time.
            # That is why `strip-comments` npm package is used to remove comments.
            #
            def js_script
              ##
              # NOTE: `main` function is created in order to have an ability to use early returns.
              #
              # IMPORTANT: Use only double quotes inside this JS script, since it is later consumed by `node -e` option wrapped by single quoutes.
              #
              # TODO: Consider to use WeakRef if memory is a concern.
              # https://ruby-doc.org/stdlib-2.5.1/libdoc/weakref/rdoc/WeakRef.html
              #
              # TODO: Jest tests for JS script.
              #
              @js_script ||= <<~JAVASCRIPT.gsub(/\n\s*/, " ")
                const main = () => {
                  const process = require("process");
                  const fs = require("fs");

                  /**
                   * TODO: try/catch when "strip-comments" is not available.
                   */
                  const strip = require("strip-comments");

                  const fileWithCommentsPath = process.argv[1];
                  const fileWithoutCommentsPath = process.argv[2];
                  const language = process.argv[3] || "ruby";

                  if (!fileWithCommentsPath) {
                    console.log("Error: Input file path is NOT passed.");

                    process.exit(1);
                  }

                  if (!fileWithoutCommentsPath) {
                    console.log("Error: Output file path is NOT passed.");

                    process.exit(1);
                  }

                  if (!["ruby", "javascript"].includes(language)) {
                    console.log("Error: Language " + language + " is NOT supported.");

                    process.exit(1);
                  }

                  const fileWithCommentsContent = fs.readFileSync(fileWithCommentsPath, { encoding: "utf8" });
                  const fileWithoutCommentsContent = strip(fileWithCommentsContent, { language });

                  fs.writeFileSync(fileWithoutCommentsPath, fileWithoutCommentsContent, { encoding: "utf8" });

                  process.exit(0);
                };

                main();
              JAVASCRIPT
            end

            def file_with_comments
              ##
              # NOTE: Tempfile is used to avoid issues with escaping of quotes inside JS script.
              #
              @file_with_comments ||= ::Tempfile.new.tap { |tempfile| tempfile.write(content_with_comments) }.tap(&:close)
            end

            def file_without_comments
              ##
              # NOTE: JS script tries to fill content of the file without comments.
              #
              @file_without_comments ||= ::Tempfile.new
            end
          end
        end
      end
    end
  end
end