---
# description: Reclaim disk on Docker / Swarm nodes — prune stopped containers, unused images, or a full system prune.
# steward:category: maintenance
# steward:confirm: true
# Reclaim disk on Docker / Docker Swarm nodes by removing unused data.
# `prune_target` selects the scope (default `system` preserves the original
# behavior for existing manual/scheduled callers that don't set it):
#   prune_target=containers   remove stopped containers only (docker container prune)
#   prune_target=images       remove unused images (docker image prune;
#                             + prune_all_images=true → -a, i.e. ALL unused, not just dangling)
#   prune_target=system       docker system prune (dangling images, stopped
#                             containers, unused networks, build cache). Widen with:
#                               prune_all_images=true   also ALL unused images
#                               prune_volumes=true       also unused named volumes (data loss risk)
- name: Docker prune
  hosts: all
  gather_facts: false
  become: true
  vars:
    prune_target: system
    prune_all_images: false
    prune_volumes: false
  tasks:
    - name: Validate prune_target
      ansible.builtin.assert:
        that: prune_target in ['containers', 'images', 'system']
        fail_msg: "prune_target must be one of: containers, images, system (got '{{ prune_target }}')"
        quiet: true

    # ── Stopped containers only ───────────────────────────────────────────────
    - name: Prune stopped containers
      ansible.builtin.command:
        argv: ['docker', 'container', 'prune', '-f']
      register: container_prune
      changed_when: "'Total reclaimed space: 0B' not in container_prune.stdout"
      when: prune_target == 'containers'

    # ── Unused images (dangling, or all unused with -a) ───────────────────────
    - name: Prune unused images
      ansible.builtin.command:
        argv: >-
          {{ ['docker', 'image', 'prune', '-f']
             + (['-a'] if prune_all_images | bool else []) }}
      register: image_prune
      changed_when: "'Total reclaimed space: 0B' not in image_prune.stdout"
      when: prune_target == 'images'

    # ── Full system prune (default) ───────────────────────────────────────────
    - name: Run docker system prune
      ansible.builtin.command:
        argv: >-
          {{ ['docker', 'system', 'prune', '-f']
             + (['-a'] if prune_all_images | bool else [])
             + (['--volumes'] if prune_volumes | bool else []) }}
      register: system_prune
      changed_when: "'Total reclaimed space: 0B' not in system_prune.stdout"
      when: prune_target == 'system'

    - name: Report reclaimed space
      ansible.builtin.debug:
        msg: >-
          {{ ((container_prune.stdout_lines | default([]))
              + (image_prune.stdout_lines | default([]))
              + (system_prune.stdout_lines | default([]))) | select | list }}