nixos/modules/services/webserver.nix

{ lib, config, ... }:
let
  cfg = config.services.webserver;

  types = {
    location = lib.types.submodule {
      options = {
        proxyPort = lib.mkOption {
          type = lib.types.nullOr lib.types.int;
          default = null;
        };
        root = lib.mkOption {
          type = lib.types.nullOr lib.types.path;
          default = null;
        };
        basicAuthFile = lib.mkOption {
          type = lib.types.nullOr lib.types.path;
          default = null;
        };
        extraConfig = lib.mkOption {
          type = lib.types.str;
          default = "";
        };
      };
    };

    vhost = lib.types.submodule {
      options = {
        proxyBuffering = lib.mkOption {
          type = lib.types.bool;
          default = true;
        };
        locations = lib.mkOption {
          type = lib.types.attrsOf types.location;
        };
        tailscaleAuth = lib.mkOption {
          type = lib.types.bool;
          default = false;
        };
        extraConfig = lib.mkOption {
          type = lib.types.lines;
          default = "";
        };
      };
    };
  };

  tailscaleAuthVhosts = lib.attrNames (
    lib.filterAttrs (name: { tailscaleAuth, ... }: tailscaleAuth) cfg.vHosts
  );
in
{
  options.services.webserver = {
    enable = lib.mkEnableOption "Enable nginx";
    acme = {
      dnsChallenge = lib.mkEnableOption "Enable DNS challenge";
      dnsProvider = lib.mkOption {
        type = lib.types.str;
        default = "hetzner";
      };
    };
    vHosts = lib.mkOption {
      type = lib.types.attrsOf types.vhost;
      default = { };
    };
    tailscaleAuth.expectedTailnet = lib.mkOption {
      type = lib.types.str;
      default = "";
    };
  };

  config = lib.mkIf cfg.enable {
    services = {
      nginx = {
        enable = lib.mkDefault true;
        recommendedProxySettings = true;
        recommendedTlsSettings = true;
        recommendedBrotliSettings = true;
        recommendedGzipSettings = true;
        recommendedOptimisation = true;

        tailscaleAuth = {
          enable = (lib.length tailscaleAuthVhosts) > 0;
          virtualHosts = tailscaleAuthVhosts;
          expectedTailnet = cfg.tailscaleAuth.expectedTailnet;
        };

        virtualHosts = lib.mapAttrs (
          _:
          {
            proxyBuffering,
            locations,
            extraConfig,
            ...
          }:
          {
            forceSSL = true;
            enableACME = true;
            http2 = true;
            acmeRoot = lib.mkIf cfg.acme.dnsChallenge null;
            extraConfig = lib.concatLines [
              (lib.optionalString (!proxyBuffering) "proxy_buffering off;")
              "charset utf-8;"
              extraConfig
            ];
            locations = lib.mapAttrs (
              _:
              {
                proxyPort,
                extraConfig,
                root,
                basicAuthFile,
              }:
              lib.mergeAttrsList [
                { inherit extraConfig root basicAuthFile; }
                (
                  if (lib.isInt proxyPort) then
                    {
                      proxyWebsockets = true;
                      proxyPass = "http://localhost:${toString proxyPort}";
                    }
                  else
                    { }
                )
              ]
            ) locations;
          }
        ) cfg.vHosts;
      };

      octodns.records = lib.filterAttrs (name: _: name != config.networking.domain) (
        lib.mapAttrs' (
          fqdn:
          { tailscaleAuth, ... }:
          {
            name = lib.removeSuffix ".${config.networking.domain}" fqdn;
            value = {
              CNAME =
                if tailscaleAuth then { target = "ts.${config.networking.domain}."; } else { toRoot = true; };
            };
          }
        ) cfg.vHosts
      );
    };

    security.acme = {
      acceptTerms = true;
      defaults = {
        email = "admin@j.repomaa.com";
        dnsProvider = lib.mkIf cfg.acme.dnsChallenge cfg.acme.dnsProvider;
      };
    };

    modules.firewall.allInterfaces = [ "web" ];
  };
}