---
# Przywrócenie primary z pg2 (replica)
# Używany w przypadku awarii pg1

# --- Auto-detect PostgreSQL version na replica ---
- name: Detect PostgreSQL version on replica
  shell: "ls -d /etc/postgresql/*/ | head -1 | xargs basename"
  register: pg_version_detect
  changed_when: false
  delegate_to: pg2
  run_once: true

- name: Set PostgreSQL variables from detection
  set_fact:
    pg_version: "{{ pg_version_detect.stdout | trim }}"
    pg_cluster: "main"
    pg_data: "/var/lib/postgresql/{{ pg_version_detect.stdout | trim }}/main"
    pg_bin_path: "/usr/lib/postgresql/{{ pg_version_detect.stdout | trim }}/bin"

- name: Wait for replica to be accessible
  wait_for:
    host: pg2
    port: 5432
    timeout: 300

# --- Promowanie replica ---
- name: Promote replica to primary
  shell: "{{ pg_bin_path }}/pg_ctl promote -D {{ pg_data }}"
  become: true
  become_user: postgres
  delegate_to: pg2
  register: promote_result

- name: Wait for promoted replica to be ready
  wait_for:
    host: pg2
    port: 5432
    timeout: 60

# --- Przywrócenie na pg1 ---
- name: Stop PostgreSQL on primary (pg1)
  systemd:
    name: postgresql
    state: stopped
  ignore_errors: true

- name: Remove old cluster data on primary
  file:
    path: "{{ pg_data }}"
    state: absent
  become: true

# --- Base backup z nowego primary (pg2) ---
- name: Perform base backup from new primary (pg2)
  shell: |
    pg_basebackup \
      -h pg2 \
      -D {{ pg_data }} \
      -U replicator \
      -Fp \
      -Xs \
      -P \
      -R
  become: true
  become_user: postgres
  register: restore_basebackup

- name: Fix permissions on restored data directory
  file:
    path: "{{ pg_data }}"
    owner: postgres
    group: postgres
    mode: "0700"
    recurse: yes
  become: true

- name: Configure recovery settings
  lineinfile:
    path: "{{ pg_data }}/standby.signal"
    line: ""
    create: yes
    owner: postgres
    group: postgres
    mode: "0644"

# --- Uruchomienie pg1 ---
- name: Start PostgreSQL on primary
  systemd:
    name: postgresql
    state: started
    enabled: yes

- name: Wait for PostgreSQL to start
  wait_for:
    path: "/var/run/postgresql/.s.PGSQL.5432"
    timeout: 60

# --- Weryfikacja ---
- name: Verify primary is accessible
  postgresql_query:
    db: postgres
    query: "SELECT version()"
    login_unix_socket_directory: /var/run/postgresql
  become: true
  become_user: postgres
  register: version_check

- name: Display restoration result
  debug:
    msg: "Primary restored successfully. PostgreSQL: {{ version_check.query_result[0].version }}"

- name: Display manual failover instructions
  debug:
    msg: |
      Restoration complete!

      Next steps:
      1. Verify pg1 and pg2 connectivity
      2. Update application connection strings if needed
      3. Monitor replication status:
         SELECT * FROM pg_stat_replication;
      4. Schedule regular test restores