{ config, lib, pkgs, ... }:
with lib;
let
  cfg = config.services.rclone-serve;

  makeNameSafe = name: builtins.replaceStrings [ "/" ] [ "-" ] name;

  daemonService = serve_config: {
    enable = true;
    requires = [ "network.target" ];
    after = [ "network.target" ]
      ++ (if serve_config.after != null then serve_config.after else [ ]);
    wantedBy = [ "multi-user.target" ];
    serviceConfig = {
      Type = "simple";
      Restart = "on-failure";
      RestartSec = "5s";

      User =
        if serve_config.user != null then "${serve_config.user}" else "root";

      ExecStart =
        "${pkgs.rclone}/bin/rclone serve ${serve_config.type} ${serve_config.remote} ${
          lib.concatStrings serve_config.extraArgs
        }";
    };
  };
in {
  options = {
    services.rclone-serve = {
      enable = mkOption {
        type = types.bool;
        default = false;
      };

      remotes = mkOption {
        type = types.listOf (types.submodule {
          options = {
            remote = mkOption { type = types.str; };
            type = mkOption { type = types.str; };
            user = mkOption { type = types.str; };
            after = mkOption { type = types.listOf types.str; };

            extraArgs = mkOption { type = types.listOf types.str; };
          };
        });
        default = [ ];
      };
    };
  };

  config = mkMerge [
    (mkIf (cfg.enable && cfg.remotes != [ ]) {
      systemd.services = listToAttrs (map (remote: {
        name = "rclone-serve-${makeNameSafe remote.remote}-${
            makeNameSafe remote.type
          }";
        value = daemonService remote;
      }) cfg.remotes);
    })
  ];
}