# frozen_string_literal: true

module GitlabQuality
  module TestTooling
    module TestMeta
      module Processor
        class AddToBlockingProcessor < MetaProcessor
          BLOCKING_METADATA = ", :blocking%{suffix}"
          BRANCH_PREFIX = 'blocking-promotion'

          class << self
            # Creates the merge requests for promoting E2E tests to :blocking
            #
            # @param [TestMetaUpdater] context instance of TestMetaUpdater
            def create_merge_requests(context)
              @context = context

              context.processed_commits.each_value do |record|
                branch, devops_stage, product_group, file, reviewer_id, assignee_handle = extract_data_from_record(record)

                mr_title = format("%{prefix} %{file}", prefix: '[E2E] PROMOTE TO BLOCKING:', file: file).truncate(72, omission: '')

                merge_request = context.create_merge_request(mr_title, branch, gitlab_bot_user_id, [reviewer_id]) do
                  merge_request_description(record, devops_stage, product_group)
                end

                context.post_note_on_merge_request(maintainer_note_on_merge_request(assignee_handle), merge_request.iid)

                if merge_request
                  Runtime::Logger.info("  Created MR for promotion to blocking: #{merge_request.web_url}")
                  record[:merge_request] = merge_request
                end
              end
            end

            # Performs post processing. Posts a list of MRs in a note on report_issue
            #
            # @param [TestMetaUpdater] context instance of TestMetaUpdater
            def post_process(context)
              web_urls = context.processed_commits.values.map { |value| "- #{value[:merge_request].web_url}\n" }.join

              return if web_urls.empty?

              context.post_note_on_issue(<<~ISSUE_NOTE, context.report_issue)
                The following merge requests have been created to promote stable specs to blocking:

                #{web_urls}
              ISSUE_NOTE
            end

            private

            attr_reader :context, :file_path, :file, :file_contents, :example_name, :mr_title, :changed_line_no, :matched_lines

            # Checks if there is already an MR open
            #
            # @return [Boolean]
            def proceed_with_commit? # rubocop:disable Metrics/AbcSize
              if changed_line_no.negative?
                Runtime::Logger.info("  No lines were changed in #{file_path}. Will not proceed with creating MR.")
                return false
              elsif context.commit_processed?(file_path, changed_line_no)
                Runtime::Logger.info("  Record already processed for #{file_path}:#{changed_line_no}. Will not proceed with creating MR.")
                return false
              elsif context.quarantined?(matched_lines, file_contents)
                Runtime::Logger.info("  This test is in quarantine: #{file_path}:#{changed_line_no}. Will not proceed with creating MR.")
                return false
              end

              true
            end

            def commit_message
              <<~COMMIT_MESSAGE
                Promote end-to-end test to blocking

                #{"Promote to blocking: #{example_name}".truncate(72)}
              COMMIT_MESSAGE
            end

            def maintainer_note_on_merge_request(assignee_handle)
              <<~MARKDOWN
                @#{assignee_handle} Please review this MR, approve and assign it to a maintainer.

                If you think this MR should not be merged, please close it and add a note of the reason to the blocking report: #{context.report_issue}
              MARKDOWN
            end

            def merge_request_description(record, devops_stage, product_group)
              <<~MARKDOWN
                  ## What does this MR do?

                  Promotes the following e2e tests to the blocking bucket:

                  #{spec_details_from_commits(record[:commits])}

                  This MR was created based on data from reliable e2e test report: #{context.report_issue}

                  /label ~"Quality" ~"QA" ~"type::maintenance"
                  /label ~"devops::#{devops_stage}"
                  #{context.label_from_product_group(product_group)}

                  <div align="center">
                  (This MR was automatically generated by [`gitlab_quality-test_tooling`](https://gitlab.com/gitlab-org/ruby/gems/gitlab_quality-test_tooling) at #{Time.now.utc})
                  </div>
              MARKDOWN
            end

            def extract_data_from_record(record)
              first_spec = record[:commits].values.first
              product_group = first_spec["product_group"]
              devops_stage = first_spec["stage"]
              reviewer_id, assignee_handle = context.fetch_dri_id(product_group, devops_stage, first_spec["section"])

              [record[:branch], devops_stage, product_group, first_spec["file"], reviewer_id, assignee_handle]
            end

            def gitlab_bot_user_id
              context.user_id_for_username(Runtime::Env.gitlab_bot_username)
            end

            # Add blocking metadata to the file content and replace it
            #
            # @return [Array<String, Integer>] first value holds the new content, the second value holds the line number of the test
            def add_metadata # rubocop:disable Metrics/AbcSize
              @matched_lines = context.find_example_match_lines(file_contents, example_name)

              if matched_lines.any? { |line| line[0].include?(':blocking') }
                Runtime::Logger.info("Example '#{example_name}' is already blocking")
                return [file_contents, -1]
              end

              context.update_matched_line(matched_lines.last, file_contents.dup) do |line|
                if line.sub(DESCRIPTION_REGEX, '').include?(',')
                  line[line.index(',', end_of_description_index(line))] = format(BLOCKING_METADATA, suffix: ',')
                else
                  line[line.rindex(' ')] = format(BLOCKING_METADATA, suffix: ' ')
                end

                line
              end
            end
          end
        end
      end
    end
  end
end