{ config, pkgs, lib, ... }:
let
  cfg = config.my.services.cgit;

  # there's no need for web crawlers on that site
  robots-deny = pkgs.writeText "robots.txt" ''
    User-agent: *
    Disallow: /
  '';

  cgitrc = ''
    # Global configuration
    virtual-root=/

    enable-http-clone=1
    clone-url=https://git.fcuny.net/$CGIT_REPO_URL

    # I've fewer than 150 repos, all should be able to be listed on
    # the main page
    max-repo-count=150

    # limit to year for the stats
    max-stats=year

    snapshots=tar.gz

    source-filter=${pkgs.cgit}/lib/cgit/filters/syntax-highlighting.py
    about-filter=${pkgs.cgit}/lib/cgit/filters/about-formatting.sh

    enable-git-config=1
    enable-index-owner=0

    remove-suffix=1

    # sort repositories by section and branches by date
    repository-sort=age
    branch-sort=age

    readme=:README.md
    readme=:README.org
    readme=:readme.org

    # print the number of modified files
    enable-log-filecount=1
    # print the number of modified lines
    enable-log-linecount=1
    enable-follow-links=1
    enable-blame=1

    root-title=¯\_(°ペ)_/¯
    root-desc=source code of my various projects

    # don't index or follow
    robots="noindex, nofollow"

    project-list=/var/lib/gitolite/projects.list
    scan-path=/var/lib/gitolite/repositories
  '';
in
{
  options.my.services.cgit = with lib; {
    enable = mkEnableOption "git web viewer";
  };

  config = lib.mkIf cfg.enable {
    services.fcgiwrap = {
      enable = true;
      user = "git";
      group = "git";
    };

    services.nginx.virtualHosts."git.fcuny.net" = {
      # make cgit the default site: if a request goes through nginx
      # without a host header, this will be the default site we serve
      # for that request.
      default = true;
      forceSSL = true;
      enableACME = true;
      listen = [
        {
          addr = "192.168.6.40";
          port = 443;
          ssl = true;
        }
        {
          addr = "192.168.6.40";
          port = 80;
          ssl = false;
        }
      ];
      locations = {
        "~* ^.+.(css|png|ico)$" = { root = "${pkgs.cgit}/cgit"; };
        # as per https://github.com/yandex/gixy/blob/master/docs/en/plugins/aliastraversal.md
        # if you want to map a single file make sure the location starts with a =, e.g =/i.gif instead of /i.gif.
        "=/robots.txt".alias = robots-deny;
        "/".extraConfig = ''
          include ${pkgs.nginx}/conf/fastcgi_params;
          fastcgi_param CGIT_CONFIG ${pkgs.writeText "cgitrc" cgitrc};
          fastcgi_param SCRIPT_FILENAME ${pkgs.cgit}/cgit/cgit.cgi;
          fastcgi_split_path_info ^(/?)(.+)$;
          fastcgi_param PATH_INFO $fastcgi_path_info;
          fastcgi_param HTTP_HOST $server_name;
          fastcgi_param QUERY_STRING $args;
          fastcgi_pass unix:${config.services.fcgiwrap.socketAddress};
          if ($http_user_agent ~* "(Blackbox Exporter)" ) {
            access_log off;
          }
        '';
      };
    };
  };
}