# frozen_string_literal: true

module TemplateFolders
  module_function

  def filter_by_full_name(template_folders, name)
    parent_name, name = name.split(' / ', 2).map(&:squish)

    if name.present?
      parent_folder = template_folders.where(parent_folder_id: nil).find_by(name: parent_name)
    else
      name = parent_name
    end

    template_folders.where(name:, parent_folder:)
  end

  def search(folders, keyword)
    return folders if keyword.blank?

    folders.where(TemplateFolder.arel_table[:name].lower.matches("%#{keyword.downcase}%"))
  end

  def filter_active_folders(template_folders, templates)
    folder_exists =
      templates.active.where(TemplateFolder.arel_table[:id].eq(Template.arel_table[:folder_id]))
               .select(1).limit(1).arel.exists

    subfolders_arel = TemplateFolder.arel_table.alias('subfolders')

    subfolder_exists =
      TemplateFolder.from(subfolders_arel)
                    .where(subfolders_arel[:parent_folder_id].eq(TemplateFolder.arel_table[:id]))
                    .where(
                      templates.active.where(Template.arel_table[:folder_id].eq(subfolders_arel[:id])).arel.exists
                    ).select(1).limit(1).arel.exists

    template_folders.where(folder_exists).or(template_folders.where(subfolder_exists))
  end

  def sort(template_folders, current_user, order)
    case order
    when 'used_at'
      subquery =
        Template.left_joins(:submissions)
                .group(:folder_id)
                .where(account_id: current_user.account_id)
                .select(
                  :folder_id,
                  Template.arel_table[:updated_at].maximum.as('updated_at_max'),
                  Submission.arel_table[:created_at].maximum.as('submission_created_at_max')
                )

      template_folders = template_folders.joins(
        Template.arel_table
                .join(subquery.arel.as('templates'), Arel::Nodes::OuterJoin)
                .on(TemplateFolder.arel_table[:id].eq(Template.arel_table[:folder_id]))
                .join_sources
      )

      template_folders.order(
        Arel::Nodes::Case.new
                         .when(Template.arel_table[:submission_created_at_max].gt(Template.arel_table[:updated_at_max]))
                         .then(Template.arel_table[:submission_created_at_max])
                         .else(Template.arel_table[:updated_at_max])
                         .desc
      )
    when 'name'
      template_folders.order(name: :asc)
    else
      template_folders.order(id: :desc)
    end
  end

  def find_or_create_by_name(author, name)
    return author.account.default_template_folder if name.blank? || name == TemplateFolder::DEFAULT_NAME

    parent_name, name = name.split(' / ', 2).map(&:squish)

    if name.present?
      parent_folder = author.account.template_folders.create_with(author:)
                            .find_or_create_by(name: parent_name, parent_folder_id: nil)
    else
      name = parent_name
    end

    author.account.template_folders.create_with(author:).find_or_create_by(name:, parent_folder:)
  end
end