action:
  - variables:
      time_left: >
        {% set event_start = as_timestamp(trigger.calendar_event.start) %} {%
        set time_diff = (event_start - as_timestamp(now())) / 60 %} {% if
        time_diff > 59 %}
          1 hour
        {% elif 29 <= time_diff < 59 %}
          30 minutes
        {% elif 14 <= time_diff < 29 %}
          15 minutes
        {% elif 4 <= time_diff < 14 %}
          5 minutes
        {% else %}
          0 minutes
        {% endif %}
      calendar_message: "Hey you've got {{ time_left }} until {{ trigger.calendar_event.summary }}."