---
# Docker Setup Playbook
# Ensures Docker and Docker Compose are installed and configured
#
# Usage:
#   ansible-playbook -i inventories/production/hosts.yml playbooks/setup-docker.yml

- name: Setup Docker for Production
  hosts: web_servers
  become: true

  vars:
    app_user: deploy
    docker_compose_version: "2.24.0"

  tasks:
    # ==========================================
    # 1. Verify Docker Installation
    # ==========================================

    - name: Check if Docker is installed
      command: docker --version
      register: docker_check
      changed_when: false
      failed_when: false

    - name: Display Docker version
      debug:
        msg: "Docker is already installed: {{ docker_check.stdout }}"
      when: docker_check.rc == 0

    - name: Install Docker if not present
      block:
        - name: Update apt cache
          apt:
            update_cache: yes

        - name: Install prerequisites
          apt:
            name:
              - apt-transport-https
              - ca-certificates
              - curl
              - gnupg
              - lsb-release
            state: present

        - name: Add Docker GPG key
          apt_key:
            url: https://download.docker.com/linux/ubuntu/gpg
            state: present

        - name: Add Docker repository
          apt_repository:
            repo: "deb [arch=amd64] https://download.docker.com/linux/ubuntu {{ ansible_distribution_release }} stable"
            state: present

        - name: Install Docker
          apt:
            name:
              - docker-ce
              - docker-ce-cli
              - containerd.io
            state: present
            update_cache: yes
      when: docker_check.rc != 0

    # ==========================================
    # 2. Configure Docker
    # ==========================================

    - name: Add deploy user to docker group
      user:
        name: "{{ app_user }}"
        groups: docker
        append: yes

    - name: Ensure Docker service is enabled and started
      systemd:
        name: docker
        enabled: yes
        state: started

    # ==========================================
    # 3. Install Docker Compose Plugin
    # ==========================================

    - name: Check if Docker Compose plugin is installed
      command: docker compose version
      register: compose_check
      changed_when: false
      failed_when: false

    - name: Display Docker Compose version
      debug:
        msg: "Docker Compose is already installed: {{ compose_check.stdout }}"
      when: compose_check.rc == 0

    # ==========================================
    # 4. Configure Docker Daemon
    # ==========================================

    - name: Create Docker daemon configuration
      copy:
        dest: /etc/docker/daemon.json
        content: |
          {
            "log-driver": "json-file",
            "log-opts": {
              "max-size": "10m",
              "max-file": "3"
            },
            "live-restore": true
          }
        owner: root
        group: root
        mode: '0644'
      notify: Restart Docker

    # ==========================================
    # 5. Firewall Configuration
    # ==========================================

    - name: Allow HTTP traffic
      ufw:
        rule: allow
        port: '80'
        proto: tcp

    - name: Allow HTTPS traffic
      ufw:
        rule: allow
        port: '443'
        proto: tcp

    # ==========================================
    # 6. Verification
    # ==========================================

    - name: Get Docker info
      command: docker info
      register: docker_info
      changed_when: false

    - name: Get Docker Compose version
      command: docker compose version
      register: compose_version
      changed_when: false

    - name: Display setup summary
      debug:
        msg:
          - "=========================================="
          - "Docker Setup Complete"
          - "=========================================="
          - "Docker Version: {{ docker_check.stdout }}"
          - "Docker Compose: {{ compose_version.stdout }}"
          - "User '{{ app_user }}' added to docker group"
          - "Firewall: HTTP (80) and HTTPS (443) allowed"
          - "=========================================="
          - ""
          - "Next Steps:"
          - "1. Log out and back in for docker group to take effect"
          - "2. Run deployment playbook to start containers"

  handlers:
    - name: Restart Docker
      systemd:
        name: docker
        state: restarted