---
- name: Check if Redis is installed
  stat:
    path: /usr/local/bin/redis-server
  register: redis_server

- name: Download and install Redis
  when: not redis_server.stat.exists
  block:
    - name: Download Redis from GitHub
      get_url:
        dest: /tmp/redis-{{ redis_version }}.tar.gz
        url: https://github.com/redis/redis/archive/{{ redis_version }}.tar.gz
        checksum: sha256:d53bb1f3e31c8893cbeda20195fa64132e35354d633231939c47b640fd401098

    - name: Create temp directory to extract Redis to
      file:
        path: /tmp/redis-{{ redis_version }}
        state: directory

    - name: Extract Redis
      unarchive:
        remote_src: true
        src: /tmp/redis-{{ redis_version }}.tar.gz
        dest: /tmp/redis-{{ redis_version }}
        extra_opts:
          - --strip-components=1

    - name: Install build dependencies for Redis
      apt:
        name: build-essential

    - name: Install Redis
      shell:
        chdir: /tmp/redis-{{ redis_version }}
        cmd: |
          make
          make install

- name: Create group for redis user
  group:
    name: redis

- name: Create redis user
  user:
    name: redis
    group: redis
    create_home: false

- name: Create /run/redis
  file:
    path: /run/redis
    state: directory
    owner: redis
    group: redis
    mode: 0755

- name: Create /var/lib/redis
  file:
    path: /var/lib/redis
    state: directory
    owner: redis
    group: redis
    mode: 0700

- name: Create /var/log/redis
  file:
    path: /var/log/redis
    state: directory
    owner: redis
    group: redis
    mode: 0744

- name: Create Redis configuration file
  template:
    src: redis.conf.jinja2
    dest: /etc/redis.conf
    owner: redis
    group: redis
    mode: 0600

- name: Create Redis service file
  copy:
    src: redis.service
    dest: /etc/systemd/system/redis.service
    owner: root
    group: root
    mode: 0644

- name: Add service file for disabling transparent hugepage
  copy:
    src: transparent_hugepage.service
    dest: /etc/systemd/system/transparent_hugepage.service
    owner: root
    group: root
    mode: 0644

- name: Check if transparent hugepage is currently enabled
  command:
    cmd: cat /sys/kernel/mm/transparent_hugepage/enabled
  register: transparent_hugepage
  changed_when: false

- name: Start and enable "disable transparent hugepage" service
  service:
    name: transparent_hugepage.service
    state: started
    enabled: true
  when: "'[never]' not in transparent_hugepage.stdout"

- name: Check if kernel overcommit mode is already set
  command:
    cmd: sysctl -n vm.overcommit_memory
  register: overcommit_memory
  changed_when: false

- name: Set kernel overcommit mode temporarily (recommended by Redis)
  command:
    cmd: sysctl vm.overcommit_memory=1
  when: overcommit_memory.stdout == "0"

- name: Make kernel overcommit mode permanent (recommended by Redis, requires restart)
  lineinfile:
    path: /etc/sysctl.conf
    line: vm.overcommit_memory = 1

- name: Start and enable redis service
  service:
    name: redis
    state: started
    enabled: true