---
- name: Update all Docker hosts
  hosts: docker_hosts
  become: yes
  gather_facts: yes
  vars:
    reboot: false
  
  tasks:
    - name: Update apt cache
      apt:
        update_cache: yes
        cache_valid_time: 3600
      
    - name: Upgrade all packages
      apt:
        upgrade: dist
        autoremove: yes
        autoclean: yes
      register: upgrade_result
    
    - name: Check if reboot is required
      stat:
        path: /var/run/reboot-required
      register: reboot_required
    
    - name: Notify if reboot needed
      debug:
        msg: "{{ inventory_hostname }} requires a reboot"
      when: reboot_required.stat.exists
    
    - name: Reboot if required and allowed
      reboot:
        msg: "Ansible triggered reboot after updates"
        reboot_timeout: 300
      when: 
        - reboot_required.stat.exists
        - reboot | bool