{ pkgs, ... }:

{
  services.nginx.virtualHosts."sb.emile.space" = {
    forceSSL = true;
    enableACME = true;
    locations = {
      "/" = {
        proxyPass = "http://${config.services.silverbullet.listenSddress}:${toString config.services.silverbullet.listenPort}";
        extraConfig = ''
          ## Send a subrequest to Authelia to verify if the user is authenticated and has permission to access the resource.
          auth_request /internal/authelia/authz;

          ## Save the upstream metadata response headers from Authelia to variables.
          auth_request_set $user $upstream_http_remote_user;
          auth_request_set $groups $upstream_http_remote_groups;
          auth_request_set $name $upstream_http_remote_name;
          auth_request_set $email $upstream_http_remote_email;

          ## Inject the metadata response headers from the variables into the request made to the backend.
          proxy_set_header Remote-User $user;
          proxy_set_header Remote-Groups $groups;
          proxy_set_header Remote-Email $email;
          proxy_set_header Remote-Name $name;

          ## Configure the redirection when the authz failure occurs. Lines starting with 'Modern Method' and 'Legacy Method'
          ## should be commented / uncommented as pairs. The modern method uses the session cookies configuration's authelia_url
          ## value to determine the redirection URL here. It's much simpler and compatible with the mutli-cookie domain easily.

          ## Modern Method: Set the $redirection_url to the Location header of the response to the Authz endpoint.
          auth_request_set $redirection_url $upstream_http_location;

          ## Modern Method: When there is a 401 response code from the authz endpoint redirect to the $redirection_url.
          error_page 401 =302 $redirection_url;

          ## Legacy Method: Set $target_url to the original requested URL.
          ## This requires http_set_misc module, replace 'set_escape_uri' with 'set' if you don't have this module.
          # set $target_url $scheme://$http_host$request_uri;

          ## Legacy Method: When there is a 401 response code from the authz endpoint redirect to the portal with the 'rd'
          ## URL parameter set to $target_url. This requires users update 'auth.example.com/' with their external authelia URL.
          # error_page 401 =302 https://sso.emile.space/?rd=$target_url;
        '';
      };
      "/internal/authelia/authz" = {
        extraConfig = ''
          ## Essential Proxy Configuration
          internal;
          proxy_pass https://sso.emile.space/api/authz/auth-request;

          ## Headers
          ## The headers starting with X-* are required.
          proxy_set_header X-Original-Method $request_method;
          proxy_set_header X-Original-URL $scheme://$http_host$request_uri;
          proxy_set_header X-Forwarded-For $remote_addr;
          proxy_set_header Content-Length "";
          proxy_set_header Connection "";

          ## Basic Proxy Configuration
          proxy_pass_request_body off;
          proxy_next_upstream error timeout invalid_header http_500 http_502 http_503; # Timeout if the real server is dead
          proxy_redirect http:// $scheme://;
          proxy_http_version 1.1;
          proxy_cache_bypass $cookie_session;
          proxy_no_cache $cookie_session;
          proxy_buffers 4 32k;
          client_body_buffer_size 128k;

          ## Advanced Proxy Configuration
          send_timeout 5m;
          proxy_read_timeout 240;
          proxy_send_timeout 240;
          proxy_connect_timeout 240;
        '';
      };

  };

  # auth via authelia
  # services.authelia.instances.main.settings.identity_providers.oidc.clients = [
  #   {
  #     id = "silverbullet";

  #     # ; nix run nixpkgs#authelia -- crypto hash generate pbkdf2 --variant sha512 --random --random.length 72 --random.charset rfc3986
  #     secret = "$pbkdf2-sha512$310000$mxk7uITQOZNYEqeinigQnw$wsF2S6RPL2zVRg1X0bAuINh8Lu5PuA/2/FYJSy3i/Ig5vtCzaIFb0xYEcus4jkqTIgyp3aBxtgSzAKjQKC.QKg";
  #     public = false;
  #     authorization_policy = "two_factor";
  #     redirect_uris = [ "https://md.emile.space/auth/oauth2/callback" ];
  #     scopes = [
  #       "openid"
  #       "email"
  #       "profile"
  #     ];
  #     grant_types = [
  #       "refresh_token"
  #       "authorization_code"
  #     ];
  #     response_types = [ "code" ];
  #     response_modes = [
  #       "form_post"
  #       "query"
  #       "fragment"
  #     ];
  #     token_endpoint_auth_method = "client_secret_post";
  #   }
  # ];

  services.silverbullet = {
    enable = true;
    spaceDir = "/var/lib/silverbullet";
    listenPort = 3000;
    listenAddress = "[::1]";
  };
}