---
- name: Native MySQL delivery
  hosts: "{{ target_hosts }}"
  become: true
  gather_facts: true
  any_errors_fatal: true
  vars:
    # --- identity ---
    mysql_instance: "{{ instance_name }}"
    mysql_version_value: "{{ mysql_version | default('8.0') }}"
    mysql_package_map:
      "8.0": "mysql-server=8.0.46-0ubuntu0.24.04.3"
    mysql_package_name: "{{ mysql_package_map[mysql_version_value] }}"

    # --- platform-allocated inputs (safe fallbacks when not passed in) ---
    # 端口池 13306–13999：平台从池分配并传入；未传时兜底池首端口，占用探测在目标机执行。
    mysql_port_value: "{{ mysql_port | default(13306) | int }}"
    # GR 组通信端口：仅 mgr_3 使用，平台成对分配；兜底为 SQL 端口 +10000。
    mysql_gr_port_value: "{{ gr_port | default((mysql_port | default(13306) | int) + 10000) | int }}"
    # 数据盘挂载点：平台按白名单选定并传入；兜底 /data。
    mysql_data_disk: "{{ data_disk | default('/data') }}"

    # --- resource quota (Go→AWX 契约单位保持 MB/GB，不擅改) ---
    mysql_memory_mb_value: "{{ memory_mb | default(4096) | int }}"
    mysql_storage_gb_value: "{{ storage_gb | default(50) | int }}"

    # --- mount-point-agnostic layout: {data_disk}/mysql-delivery/{instance_id}/... ---
    mysql_base_dir: "{{ mysql_data_disk }}/mysql-delivery/{{ mysql_instance }}"
    mysql_install_dir: "/opt/mysql-delivery/{{ mysql_instance }}"
    mysql_data_dir: "{{ mysql_base_dir }}/data"
    mysql_log_dir: "{{ mysql_base_dir }}/logs"
    mysql_binlog_dir: "{{ mysql_base_dir }}/logs/binlog"
    mysql_redo_dir: "{{ mysql_base_dir }}/logs/redo"
    mysql_tmp_dir: "{{ mysql_base_dir }}/tmp"
    # socket/pid 走 /run tmpfs（重启自动清理），由 systemd RuntimeDirectory 创建。
    mysql_run_dir: "/run/mysql-delivery-{{ mysql_instance }}"
    mysql_config_file: "/etc/mysql/mysql-delivery/{{ mysql_instance }}.cnf"

    # --- database config (user form, with doc default baselines) ---
    mysql_timezone: "{{ timezone | default('+08:00') }}"
    mysql_lower_case_table_names: "{{ lower_case_table_names | default(1) | int }}"
    mysql_character_set: "{{ character_set | default('utf8mb4') }}"
    mysql_collation: "{{ collation | default('utf8mb4_general_ci') }}"

    # --- advanced params (overridable; default baseline assumes SSD for io_capacity) ---
    mysql_flush_log_at_trx_commit: "{{ innodb_flush_log_at_trx_commit | default(1) | int }}"
    mysql_sync_binlog: "{{ sync_binlog | default(1) | int }}"
    mysql_io_capacity: "{{ innodb_io_capacity | default(2000) | int }}"
    mysql_long_query_time: "{{ long_query_time | default(1) }}"
    mysql_binlog_expire_logs_seconds: "{{ binlog_expire_logs_seconds | default(604800) | int }}"
    mysql_max_binlog_size: "{{ max_binlog_size | default('256M') }}"
    mgr_group_name: "{{ group_replication_group_name | default('aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa') }}"

    # --- expected node count per topology ---
    mysql_expected_hosts: "{{ {'standalone': 1, 'primary_replica': 2, 'mgr_3': 3}[topology | default('standalone')] }}"

    # --- secrets (injected via environment) ---
    mysql_root_password_value: "{{ lookup('ansible.builtin.env', 'XINFRA_MYSQL_ROOT_PASSWORD') }}"
    mysql_admin_password_value: "{{ lookup('ansible.builtin.env', 'XINFRA_MYSQL_ADMIN_PASSWORD') }}"

  pre_tasks:
    - name: Validate delivery parameters
      ansible.builtin.assert:
        that:
          - topology in ['standalone', 'primary_replica', 'mgr_3']
          - mysql_instance is match('^[a-z0-9][a-z0-9-]{0,62}$')
          - mysql_version_value in mysql_package_map
          - mysql_data_disk is match('^/')
          - (mysql_port_value | int) >= 13306
          - (mysql_port_value | int) <= 13999
          - (mysql_memory_mb_value | int) >= 2048
          - (mysql_memory_mb_value | int) <= 65536
          - (mysql_storage_gb_value | int) >= 20
          - (mysql_storage_gb_value | int) <= 2000
          - (mysql_lower_case_table_names | int) in [0, 1]
          - mysql_root_password_value | length >= 16
          - mysql_admin_password_value | length >= 16
        fail_msg: >-
          Delivery parameters out of the supported target-state whitelist
          (topology / version-package-map / port pool 13306-13999 / memory 2-64G / storage 20-2000G).
        quiet: true
      no_log: true

    - name: Validate topology host count
      ansible.builtin.assert:
        that:
          - (ansible_play_hosts_all | length | int) == (mysql_expected_hosts | int)
        fail_msg: "topology={{ topology }} expects {{ mysql_expected_hosts }} host(s), got {{ ansible_play_hosts_all | length }}"
      run_once: true

    - name: Probe target-host port occupancy (SQL + GR)
      ansible.builtin.shell: |
        set -o pipefail
        for p in {{ mysql_probe_ports | join(' ') }}; do
          if ss -lntH "sport = :${p}" | grep -q .; then
            # already listening: only tolerated when owned by this instance service
            if ! systemctl is-active --quiet "mysql-delivery@{{ mysql_instance }}.service"; then
              echo "port ${p} already in use on target host" >&2
              exit 3
            fi
          fi
        done
      args:
        executable: /bin/bash
      vars:
        mysql_probe_ports: "{{ [mysql_port_value, mysql_gr_port_value] if topology == 'mgr_3' else [mysql_port_value] }}"
      changed_when: false

    - name: Read currently available memory (point-in-time guard)
      ansible.builtin.shell: awk '/^MemAvailable:/ { print int($2 / 1024) }' /proc/meminfo
      args:
        executable: /bin/bash
      register: mysql_available_memory
      changed_when: false

    - name: Resolve data-disk mountpoint available space
      ansible.builtin.set_fact:
        mysql_mount_avail: >-
          {{ (ansible_mounts | selectattr('mount', 'equalto', mysql_data_disk)
              | map(attribute='size_available') | first)
             | default(ansible_mounts | selectattr('mount', 'equalto', '/')
              | map(attribute='size_available') | first) }}

    - name: Check available memory and data-disk space
      ansible.builtin.assert:
        that:
          - (mysql_available_memory.stdout | int) >= (mysql_memory_mb_value | int)
          - (mysql_mount_avail | int) >= (mysql_storage_gb_value | int) * 1073741824
        fail_msg: >-
          Target host lacks memory or free space on {{ mysql_data_disk }};
          host-wide Σ-quota budgeting is the platform's responsibility, this is a last-resort guard.

  tasks:
    - name: Detect an existing Ubuntu MySQL package
      ansible.builtin.command: dpkg-query -W mysql-server
      register: mysql_package_before
      failed_when: false
      changed_when: false

    - name: Install Ubuntu MySQL package
      ansible.builtin.apt:
        name: "{{ mysql_package_name }}"
        state: present
        update_cache: true
        cache_valid_time: 3600

    - name: Stop the automatically created default instance on a clean host
      ansible.builtin.systemd_service:
        name: mysql.service
        state: stopped
        enabled: false
      when: mysql_package_before.rc != 0

    - name: Check for the bundled MySQL AppArmor profile
      ansible.builtin.stat:
        path: /etc/apparmor.d/usr.sbin.mysqld
      register: mysql_apparmor_profile

    - name: Authorize the delivery paths in the MySQL AppArmor profile
      ansible.builtin.copy:
        dest: /etc/apparmor.d/local/usr.sbin.mysqld
        owner: root
        group: root
        mode: '0644'
        content: |
          # Managed by XINFRA MySQL delivery - grant per-instance native paths
          {{ mysql_data_disk }}/mysql-delivery/ r,
          {{ mysql_data_disk }}/mysql-delivery/** rwk,
          /run/mysql-delivery-*/ rw,
          /run/mysql-delivery-*/** rwk,
      when: mysql_apparmor_profile.stat.exists
      register: mysql_apparmor_local

    - name: Reload the MySQL AppArmor profile
      ansible.builtin.command: apparmor_parser -r /etc/apparmor.d/usr.sbin.mysqld
      when: mysql_apparmor_profile.stat.exists and mysql_apparmor_local.changed
      changed_when: true

    - name: Create instance directories (mount-point-agnostic layout)
      ansible.builtin.file:
        path: "{{ item.path }}"
        state: directory
        owner: "{{ item.owner }}"
        group: "{{ item.group }}"
        mode: "{{ item.mode }}"
      loop:
        - { path: /etc/mysql/mysql-delivery, owner: root, group: mysql, mode: '0750' }
        - { path: "{{ mysql_install_dir }}", owner: root, group: root, mode: '0755' }
        - { path: "{{ mysql_base_dir }}", owner: mysql, group: mysql, mode: '0750' }
        - { path: "{{ mysql_data_dir }}", owner: mysql, group: mysql, mode: '0750' }
        - { path: "{{ mysql_log_dir }}", owner: mysql, group: mysql, mode: '0750' }
        - { path: "{{ mysql_binlog_dir }}", owner: mysql, group: mysql, mode: '0750' }
        - { path: "{{ mysql_redo_dir }}", owner: mysql, group: mysql, mode: '0750' }
        - { path: "{{ mysql_tmp_dir }}", owner: mysql, group: mysql, mode: '0750' }

    - name: Link native binaries into the instance directory
      ansible.builtin.file:
        src: "{{ item.src }}"
        dest: "{{ mysql_install_dir }}/{{ item.dest }}"
        state: link
      loop:
        - { src: /usr/sbin/mysqld, dest: mysqld }
        - { src: /usr/bin/mysql, dest: mysql }
        - { src: /usr/bin/mysqladmin, dest: mysqladmin }

    - name: Calculate host role and server id
      ansible.builtin.set_fact:
        mysql_node_index: "{{ ansible_play_hosts_all.index(inventory_hostname) }}"
        mysql_node_role: >-
          {{ 'standalone' if topology == 'standalone' else
             ('primary' if ansible_play_hosts_all.index(inventory_hostname) == 0 else
             ('replica' if topology == 'primary_replica' else 'mgr')) }}
        # host-wide unique: platform may pass explicit mysql_server_id; otherwise derive
        # port + node index (ports are unique per host in the pool model).
        mysql_server_id_value: >-
          {{ mysql_server_id | default((mysql_port_value | int)
             + (ansible_play_hosts_all.index(inventory_hostname))) | int }}

    - name: Resolve memory tier (GB)
      ansible.builtin.set_fact:
        mysql_memory_gb: "{{ ((mysql_memory_mb_value | int) // 1024) | int }}"

    - name: Resolve linkage-derived defaults (illustrative tiers, pending hardware calibration)
      ansible.builtin.set_fact:
        mysql_max_connections: >-
          {{ (max_connections | int) if (max_connections is defined and (max_connections | string) != 'auto')
             else (200 if (mysql_memory_gb | int) <= 2
             else 500 if (mysql_memory_gb | int) <= 4
             else 1000 if (mysql_memory_gb | int) <= 8
             else 2000 if (mysql_memory_gb | int) <= 16
             else 4000 if (mysql_memory_gb | int) <= 32
             else 8000 if (mysql_memory_gb | int) <= 64
             else 16000) }}
        mysql_redo_capacity: >-
          {{ innodb_redo_log_capacity if (innodb_redo_log_capacity is defined)
             else ('128M' if (mysql_memory_gb | int) <= 4
             else '256M' if (mysql_memory_gb | int) <= 16
             else '512M' if (mysql_memory_gb | int) <= 32
             else '1G') }}

    - name: Write instance configuration
      ansible.builtin.template:
        src: templates/mysql-instance.cnf.j2
        dest: "{{ mysql_config_file }}"
        owner: root
        group: mysql
        mode: '0640'
      notify: Restart MySQL delivery instance

    - name: Initialize the data directory once
      ansible.builtin.command:
        argv:
          - /usr/sbin/mysqld
          - "--defaults-file={{ mysql_config_file }}"
          - --initialize-insecure
          - --user=mysql
      args:
        creates: "{{ mysql_data_dir }}/auto.cnf"
      no_log: true

    - name: Install the delivery systemd template
      ansible.builtin.copy:
        src: files/mysql-delivery@.service
        dest: /etc/systemd/system/mysql-delivery@.service
        owner: root
        group: root
        mode: '0644'
      register: mysql_systemd_unit

    - name: Reload systemd units
      ansible.builtin.systemd_service:
        daemon_reload: true
      when: mysql_systemd_unit.changed

    - name: Start the MySQL delivery instance
      ansible.builtin.systemd_service:
        name: "mysql-delivery@{{ mysql_instance }}.service"
        state: started
        enabled: true

    - name: Wait for the local MySQL socket
      ansible.builtin.wait_for:
        path: "{{ mysql_run_dir }}/mysql.sock"
        timeout: 60

    - name: Configure local administrative accounts
      ansible.builtin.shell: |
        set -euo pipefail
        client_file="$(mktemp)"
        sql_file="$(mktemp)"
        trap 'rm -f "$client_file" "$sql_file"' EXIT
        chmod 600 "$client_file" "$sql_file"
        cat >"$client_file" <<'EOF'
        [client]
        user=root
        password={{ mysql_root_password_value }}
        socket={{ mysql_run_dir }}/mysql.sock
        EOF
        if ! /usr/bin/mysql --defaults-extra-file="$client_file" -e 'SELECT 1' >/dev/null 2>&1; then
          cat >"$sql_file" <<'EOF'
        ALTER USER 'root'@'localhost' IDENTIFIED BY '{{ mysql_root_password_value | replace("'", "''") }}';
        EOF
          /usr/bin/mysql --protocol=socket --socket={{ mysql_run_dir }}/mysql.sock -uroot <"$sql_file"
        fi
        cat >"$sql_file" <<'EOF'
        CREATE USER IF NOT EXISTS 'xinfra_admin'@'%' IDENTIFIED BY '{{ mysql_admin_password_value | replace("'", "''") }}';
        ALTER USER 'xinfra_admin'@'%' IDENTIFIED BY '{{ mysql_admin_password_value | replace("'", "''") }}';
        GRANT ALL PRIVILEGES ON *.* TO 'xinfra_admin'@'%' WITH GRANT OPTION;
        FLUSH PRIVILEGES;
        EOF
        /usr/bin/mysql --defaults-extra-file="$client_file" <"$sql_file"
      args:
        executable: /bin/bash
      changed_when: false
      no_log: true

    - name: Verify MySQL TCP health
      ansible.builtin.wait_for:
        host: "{{ ansible_host | default(inventory_hostname) }}"
        port: "{{ mysql_port_value }}"
        timeout: 30

    - name: Note pending HA runtime orchestration
      ansible.builtin.debug:
        msg: >-
          topology={{ topology }} deployed with HA-ready config (GTID/binlog/relay/GR settings in place),
          but replication wiring (CHANGE REPLICATION SOURCE) and Group Replication bootstrap
          (START GROUP_REPLICATION) are not yet automated — nodes start config-ready only.
      when: topology != 'standalone'
      run_once: true

  handlers:
    - name: Restart MySQL delivery instance
      ansible.builtin.systemd_service:
        name: "mysql-delivery@{{ mysql_instance }}.service"
        state: restarted