openproject/app/cells/settings/time_zone_setting_cell.rb

module Settings
  ##
  # A text field to enter numeric values.
  class TimeZoneSettingCell < ::RailsCell
    include ActionView::Helpers::FormOptionsHelper
    include SettingsHelper

    options :form, :title
    options container_class: "-wide"
    options include_blank: true

    # name of setting and tag
    def name
      model
    end

    def render_select
      if form.nil?
        render_setting_select
      else
        render_form_select
      end
    end

    def render_form_select
      form.select(
        name,
        time_zone_entries,
        include_blank: include_blank,
        container_class: container_class,
        title: title
      )
    end

    def render_setting_select
      setting_select(
        name,
        time_zone_entries,
        include_blank: include_blank,
        container_class: container_class,
        title: title
      )
    end

    def time_zone_entries
      contract
        .assignable_time_zones
        .map do |tz|
        [tz.to_s, tz.tzinfo.canonical_identifier]
      end
    end

    private

    def contract
      @contract ||= UserPreferences::UpdateContract.new(form.object, User.current)
    end
  end
end