- name: Configure swap file for PostgreSQL node
  hosts: dev
  become: true
  vars:
    swap_file_path: /swapfile
    swap_file_size_mb: 4096  # 4 GB
  
  tasks:
    - name: Check if swap file already exists
      stat:
        path: "{{ swap_file_path }}"
      register: swap_file_check

    - name: Create swap file
      command: dd if=/dev/zero of={{ swap_file_path }} bs=1M count={{ swap_file_size_mb }}
      when: not swap_file_check.stat.exists
      register: swap_created

    - name: Set correct permissions on swap file
      file:
        path: "{{ swap_file_path }}"
        owner: root
        group: root
        mode: '0600'
      when: swap_created is changed

    - name: Format swap file
      command: mkswap {{ swap_file_path }}
      when: swap_created is changed
      register: swap_formatted

    - name: Enable swap file
      command: swapon {{ swap_file_path }}
      when: swap_formatted is changed

    - name: Check if swap is already in fstab
      lineinfile:
        path: /etc/fstab
        regexp: '^{{ swap_file_path }}'
        state: absent
      check_mode: true
      register: fstab_check
      changed_when: false

    - name: Add swap to fstab for persistence
      lineinfile:
        path: /etc/fstab
        line: '{{ swap_file_path }} none swap sw 0 0'
        state: present
      when: fstab_check.found == 0

    - name: Verify swap is active
      command: swapon --show
      register: swap_status
      changed_when: false

    - name: Display swap status
      debug:
        var: swap_status.stdout_lines