# SPDX-FileCopyrightText: 2024 Tom Hubrecht <tom.hubrecht@dgnum.eu>
#
# SPDX-License-Identifier: EUPL-1.2

{ lib, config, ... }:

let
  inherit (lib)
    attrValues
    genAttrs
    mkDefault
    mkIf
    mkMerge
    mkOption
    optional
    ;

  inherit (lib.types)
    attrs
    attrsOf
    bool
    ints
    listOf
    nullOr
    submodule
    str
    ;

  cfg = config.isp;
in

{
  options.isp = {
    vlans = mkOption {
      type = attrsOf (
        submodule (
          { config, ... }:
          {
            options = {
              flags = mkOption {
                type = listOf str;
                default = optional config.userOnly "users";
                defaultText = ''optional config.userOnly "users"'';
                description = ''
                  Groups of VLANs this VLAN belong to.
                '';
              };

              id = mkOption {
                type = ints.between 0 (4096 - 1);
                description = ''
                  The VLAN id to use.
                '';
              };

              settings = mkOption {
                type = attrs;
                default = { };
                description = ''
                  Settings for the configuration of networkd.
                '';
              };

              internal = {
                network = mkOption {
                  type = nullOr str;
                  description = ''
                    The internal network address of this VLAN.
                  '';
                };

                prefix = mkOption {
                  type = nullOr (ints.between 0 32);
                  default = if config.userOnly then 27 else null;
                  description = ''
                    The prefix length of the network associated to this VLAN.
                  '';
                };

                address = mkOption {
                  type = nullOr str;
                  description = ''
                    The router address in the VLAN. It should be the first ipv4 in the network.
                  '';
                };

                cidr = mkOption {
                  type = nullOr str;
                  default =
                    with config.internal;
                    if (prefix != null && network != null) then "${network}/${builtins.toString prefix}" else null;
                  description = ''
                    The CIDR notation of the network associated to the VLAN.
                  '';
                };
              };

              userOnly = mkOption {
                type = bool;
                default = false;
                description = ''
                  Whether this VLAN is only used by a user in the context of the IPS.
                  I.e. this is not an administration VLAN.
                '';
              };
            };

            # The address is null by default when not on a user VLAN
            config.internal = mkIf (!config.userOnly) {
              address = mkDefault null;
              network = mkDefault null;
            };
          }
        )
      );
      default = { };
      description = ''
        The list of VLANs known to our ISP.
      '';
    };

    vlans-groups = mkOption {
      type = attrsOf (submodule {
        options.id-list = mkOption {
          type = listOf (ints.between 0 (4096 - 1));
          description = ''
            List of VLANs IDs inside this group.
          '';
        };
      });
      default = { };
      description = ''
        The list of groups of VLANs known to our ISP.
      '';
    };
  };
  config.isp.vlans-groups = mkMerge (
    map (
      { flags, id, ... }:
      genAttrs flags (_: {
        id-list = [ id ];
      })
    ) (attrValues cfg.vlans)
  );
}