---
- name: Assert usage of systemd as an init system
  ansible.builtin.assert:
    that: ansible_service_mgr == 'systemd'
    msg: "This module only works with systemd"

- name: Install package fact dependencies
  ansible.builtin.package:
    name: "{{ _pkg_fact_req }}"
    state: present
  when: (_pkg_fact_req)
  vars:
    _pkg_fact_req: "{% if (ansible_pkg_mgr == 'apt') %}\
                    {{ ('python-apt' if ansible_python_version is version('3', '<') else 'python3-apt') }}
                    {% else %}\
                    {% endif %}"

- name: Gather package facts
  ansible.builtin.package_facts:
  when: "not 'packages' in ansible_facts"

- name: Assert no duplicate config flags
  ansible.builtin.assert:
    that:
      - prometheus_config_flags_extra['config.file'] is not defined
      - prometheus_config_flags_extra['storage.tsdb.path'] is not defined
      - prometheus_config_flags_extra['storage.local.path'] is not defined
      - prometheus_config_flags_extra['web.listen-address'] is not defined
      - prometheus_config_flags_extra['web.external-url'] is not defined
    msg: "Detected duplicate configuration entry. Please check your ansible variables and role README.md."

- name: Assert external_labels aren't configured twice
  ansible.builtin.assert:
    that: prometheus_global.external_labels is not defined
    msg: "Use prometheus_external_labels to define external labels"

- name: Fail when prometheus_config_flags_extra duplicates parameters set by other variables
  ansible.builtin.fail:
    msg: >
      Whooops. You are duplicating configuration. Please look at your prometheus_config_flags_extra
      and check against other variables in defaults/main.yml
  with_items:
    - 'storage.tsdb.retention'
    - 'storage.tsdb.path'
    - 'storage.local.retention'
    - 'storage.local.path'
    - 'config.file'
    - 'web.listen-address'
    - 'web.external-url'
  when: item in prometheus_config_flags_extra.keys()

- name: Get all file_sd files from scrape_configs
  ansible.builtin.set_fact:
    file_sd_files: "{{ prometheus_scrape_configs | selectattr('file_sd_configs', 'defined') | map(attribute='file_sd_configs') |
                    flatten | map(attribute='files') | flatten }}"

- name: Fail when file_sd targets are not defined in scrape_configs
  ansible.builtin.fail:
    msg: >
      Oh, snap! `{{ item.key }}` couldn't be found in your scrape configs. Please ensure you provided
      all targets from prometheus_targets in prometheus_scrape_configs
  when: not prometheus_config_dir + "/file_sd/" + item.key + ".yml" in file_sd_files
  #  when: not item | basename | splitext | difference(['.yml']) | join('') in prometheus_targets.keys()
  with_dict: "{{ prometheus_targets }}"

- name: Alert when prometheus_alertmanager_config is empty, but prometheus_alert_rules is specified
  ansible.builtin.debug:
    msg: >
      No alertmanager configuration was specified. If you want your alerts to be sent make sure to
      specify a prometheus_alertmanager_config in defaults/main.yml.
  when:
    - prometheus_alertmanager_config == []
    - prometheus_alert_rules != []

- name: Discover latest version
  ansible.builtin.set_fact:
    prometheus_version: "{{ (lookup('url', 'https://api.github.com/repos/prometheus/prometheus/releases/latest', split_lines=False) |
                         from_json).get('tag_name') | replace('v', '') }}"
  run_once: true
  until: prometheus_version is version('0.0.0', '>=')
  retries: 10
  when:
    - prometheus_version == "latest"
    - prometheus_binary_local_dir | length == 0
    - not prometheus_skip_install

- name: Get prometheus binary checksum
  when:
    - prometheus_binary_local_dir | length == 0
    - not prometheus_skip_install
  block:
    - name: "Get checksum list"
      ansible.builtin.set_fact:
        __prometheus_checksums: "{{ lookup('url', prometheus_checksums_url, wantlist=True) | list }}"
      run_once: true
      until: __prometheus_checksums is search('linux-' + go_arch + '.tar.gz')
      retries: 10

    - name: "Get checksum for {{ go_arch }}"
      ansible.builtin.set_fact:
        __prometheus_checksum: "{{ item.split(' ')[0] }}"
      with_items: "{{ __prometheus_checksums }}"
      when:
        - "('linux-' + go_arch + '.tar.gz') in item"