- set_fact:
    matrix_systemd_services_list: "{{ matrix_systemd_services_list + ['matrix-registration'] }}"
  when: matrix_registration_enabled|bool

- block:
  - name: Fail if matrix-nginx-proxy role already executed
    fail:
      msg: >-
        Trying to append matrix-registration's reverse-proxying configuration to matrix-nginx-proxy,
        but it's pointless since the matrix-nginx-proxy role had already executed.
        To fix this, please change the order of roles in your plabook,
        so that the matrix-nginx-proxy role would run after the matrix-registration role.
    when: matrix_nginx_proxy_role_executed|default(False)|bool

  - name: Generate matrix-registration proxying configuration for matrix-nginx-proxy
    set_fact:
      matrix_registration_matrix_nginx_proxy_configuration: |
        rewrite ^{{ matrix_registration_public_endpoint }}$ $scheme://$server_name{{ matrix_registration_public_endpoint }}/ permanent;
        rewrite ^{{ matrix_registration_public_endpoint }}/$ $scheme://$server_name{{ matrix_registration_public_endpoint }}/register redirect;

        location ~ ^{{ matrix_registration_public_endpoint }}/(.*) {
        {% if matrix_nginx_proxy_enabled|default(False) %}
          {# Use the embedded DNS resolver in Docker containers to discover the service #}
          resolver 127.0.0.11 valid=5s;
          set $backend "matrix-registration:5000";
          proxy_pass http://$backend/$1;
        {% else %}
          {# Generic configuration for use outside of our container setup #}
          proxy_pass http://127.0.0.1:8767/$1;
        {% endif %}

          {#
            Workaround matrix-registration serving the background image at /static
            (see https://github.com/ZerataX/matrix-registration/issues/47)
          #}
          sub_filter_once off;
          sub_filter_types text/css;
          sub_filter "/static/" "{{ matrix_registration_public_endpoint }}/static/";
        }

  - name: Register matrix-registration proxying configuration with matrix-nginx-proxy
    set_fact:
      matrix_nginx_proxy_proxy_matrix_additional_server_configuration_blocks: |
        {{
          matrix_nginx_proxy_proxy_matrix_additional_server_configuration_blocks|default([])
          +
          [matrix_registration_matrix_nginx_proxy_configuration]
        }}
  tags:
    - always
  when: matrix_registration_enabled|bool

- name: Warn about reverse-proxying if matrix-nginx-proxy not used
  debug:
    msg: >-
      NOTE: You've enabled the matrix-registration tool but are not using the matrix-nginx-proxy
      reverse proxy.
      Please make sure that you're proxying the `{{ matrix_registration_public_endpoint }}`
      URL endpoint to the matrix-registration container.
      You can expose the container's port using the `matrix_registration_container_http_host_bind_port` variable.
  when: "matrix_registration_enabled|bool and matrix_nginx_proxy_enabled is not defined"