{ config, lib, ... }:
with lib;
let
  cfg = config.nixfiles.modules.hydra;
in
{
  options.nixfiles.modules.hydra = {
    enable = mkEnableOption "Hydra";

    domain = mkOption {
      description = "Domain name sans protocol scheme.";
      type = with types; str;
      default = "hydra.${config.networking.domain}";
    };

    port = mkOption {
      description = "Port.";
      type = with types; port;
      default = 7754;
    };
  };

  config = mkIf cfg.enable {
    nixfiles.modules = {
      nginx = {
        enable = true;
        upstreams.hydra.servers."127.0.0.1:${toString cfg.port}" = { };
        virtualHosts.${cfg.domain}.locations."/".proxyPass = "http://hydra";
      };
      postgresql.enable = true;
    };

    services =
      let
        db = "hydra";
      in
      {
        hydra = {
          enable = true;
          listenHost = "127.0.0.1";
          inherit (cfg) port;
          dbi = "dbi:Pg:dbname=${db};user=${db}";
          hydraURL = cfg.domain;
        };

        postgresql = {
          ensureDatabases = [ db ];
          ensureUsers = [
            {
              name = db;
              ensureDBOwnership = true;
            }
          ];
        };
      };
  };
}