ManageIQ/miq_bot

module GithubService
  module Commands
    class AddLabel < Base
      include IsTeamMember

      def unassignable_labels
        @unassignable_labels ||= Settings.labels.unassignable.to_h.stringify_keys
      end

      private

      def _execute(issuer:, value:)
        valid, invalid = extract_label_names(value)
        process_extracted_labels(issuer, valid, invalid)

        if invalid.any?
          issue.add_comment(invalid_label_message(issuer, invalid))
        end

        if valid.any?
          valid.reject! { |l| issue.applied_label?(l) }
          issue.add_labels(valid) if valid.any?
        end
      end

      def extract_label_names(value)
        label_names = value.split(",").map { |label| label.strip.downcase }
        validate_labels(label_names)
      end

      def validate_labels(label_names)
        # First reload the cache if there are any invalid labels
        GithubService.refresh_labels(issue.fq_repo_name) unless label_names.all? { |l| GithubService.valid_label?(issue.fq_repo_name, l) }

        # Then see if any are *still* invalid and split the list
        label_names.partition { |l| GithubService.valid_label?(issue.fq_repo_name, l) }
      end

      def process_extracted_labels(issuer, valid_labels, invalid_labels)
        correct_invalid_labels(valid_labels, invalid_labels)
        handle_unassignable_labels(valid_labels) unless triage_member?(issuer)

        [valid_labels, invalid_labels]
      end

      def correct_invalid_labels(valid_labels, invalid_labels)
        available_labels = GithubService.labels(issue.fq_repo_name)

        invalid_labels.reject! do |label|
          corrections = DidYouMean::SpellChecker.new(:dictionary => available_labels).correct(label)

          if corrections.count == 1
            valid_labels << corrections.first
          end
        end
      end

      def handle_unassignable_labels(valid_labels)
        valid_labels.map! do |label|
          unassignable_labels.key?(label) ? unassignable_labels[label] : label
        end
      end

      def invalid_label_message(issuer, invalid_labels)
        message  = issuer == GithubService.bot_name ? "" : "@#{issuer} "
        message << "Cannot apply the following label"
        message << "s" if invalid_labels.length > 1
        message << " because they are not recognized:\n"

        labels = GithubService.labels(issue.fq_repo_name)
        invalid_labels.each do |bad_label|
          corrections   = DidYouMean::SpellChecker.new(:dictionary => labels).correct(bad_label)
          possibilities = corrections.map { |l| "`#{l}`" }.join(", ")

          message << "* `#{bad_label}` "
          message << "(Did you mean? #{possibilities})" if corrections.any?
          message << "\n"
        end
        message << "\nAll labels for `#{issue.fq_repo_name}`:  https://github.com/#{issue.fq_repo_name}/labels"
      end
    end
  end
end

# HACK: CI / `bundle install --path ...` compat
begin
  retry_require_dym = false
  require 'did_you_mean'
rescue LoadError => error
  if retry_require_dym
    raise error
  else
    $LOAD_PATH.push(*Dir[File.join(Gem.default_dir, "gems", "did_you_mean*", "lib")])
    $LOAD_PATH.uniq!
    retry_require_dym = true
    retry
  end
end