{ config, lib, pkgs, ... }:

with lib;

let

  cfg = config.custom.samba-share;

in {

  options.custom.samba-share = {
    enable = mkEnableOption "enable custom.samba-share";
    folders = mkOption {
      default = { };
      type = with types; attrsOf str;
      description = ''
        folders to share as readonly
      '';
      example = { public = "/srv/downloads/movies"; };
    };
    private = mkOption {
      default = { };
      type = with types;
        attrsOf (submodule {
          options = {
            users = mkOption {
              type = with types; str;
              description = ''
                System users allowed to access the folder.
                To set password:
                # nix-shell -p samba
                # smbpasswd -a <user>
              '';
            };
            folder = mkOption { type = with types; str; };
          };
        });
    };
  };

  config = mkMerge [

    (mkIf cfg.enable {

      networking.firewall.enable = true;
      networking.firewall.allowPing = true;
      networking.firewall.allowedTCPPorts = [ 445 139 ];
      networking.firewall.allowedUDPPorts = [ 137 138 ];

      services.samba = {
        enable = true;
        # services.samba.securityType = "share";
        extraConfig = ''
          guest account = smbguest
          map to guest = bad user

          # disable printing
          load printers = no
          printing = bsd
          printcap name = /dev/null
          disable spoolss = yes
        '';

        shares = mapAttrs' (name: path: {
          name = name;
          value = {
            browsable = "yes";
            comment = "read only share ${name}";
            path = path;
            "read only" = "yes";
            "guest ok" = "yes";
          };
        }) cfg.folders // (mapAttrs' (name:
          { users, folder, ... }: {
            name = name;
            value = {
              browsable = "yes";
              comment = "read only share ${name}";
              path = folder;
              "read only" = "no";
              "valid users" = users;
              "guest ok" = "false";
            };
          }) cfg.private);
      };

      users.users.smbguest = {
        name = "smbguest";
        uid = config.ids.uids.smbguest;
        description = "smb guest user";
        home = "/home/smbguest";
        createHome = true;
      };

    })
    # todo : maybe better to have a parameter for this
    (mkIf config.services.syncthing.enable {
      users.groups."syncthing".members = [ "smbguest" ];
    })
  ];
}