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

with lib;

let
  cfg = config.services.naxos.shares.samba;
in {
  options.services.naxos.shares.samba = {
    enable = mkEnableOption "NaxOS Declarative Samba (SMB) Service";

    workgroup = mkOption {
      type = types.str;
      default = "WORKGROUP";
      description = "NetBIOS workgroup.";
    };

    serverString = mkOption {
      type = types.str;
      default = "NaxOS Storage Appliance";
      description = "Server announcement string.";
    };

    netbiosName = mkOption {
      type = types.str;
      default = "naxos";
      description = "NetBIOS hostname.";
    };

    allowedHosts = mkOption {
      type = types.listOf types.str;
      default = [ "10.0.0." "192.168." "172.16." "127.0.0.1" "localhost" ];
      description = "Allowed IP subnets or hosts for SMB access.";
    };

    shares = mkOption {
      type = types.attrsOf (types.submodule {
        options = {
          enable = mkOption {
            type = types.bool;
            default = true;
            description = "Whether to publish this share.";
          };
          path = mkOption {
            type = types.str;
            description = "Target local directory or ZFS mountpoint.";
          };
          comment = mkOption {
            type = types.str;
            default = "";
            description = "Share description.";
          };
          readOnly = mkOption {
            type = types.bool;
            default = false;
            description = "Whether the share is read-only.";
          };
          browseable = mkOption {
            type = types.bool;
            default = true;
            description = "Whether the share is visible in network browsing.";
          };
          guestOk = mkOption {
            type = types.bool;
            default = false;
            description = "Whether anonymous/guest access is allowed.";
          };
          validUsers = mkOption {
            type = types.listOf types.str;
            default = [];
            description = "List of valid users or @groups.";
          };
          forceUser = mkOption {
            type = types.nullOr types.str;
            default = null;
            description = "Force UNIX user for all connections.";
          };
          forceGroup = mkOption {
            type = types.nullOr types.str;
            default = null;
            description = "Force UNIX group for all connections.";
          };
          createMask = mkOption {
            type = types.str;
            default = "0664";
            description = "File creation permission mask.";
          };
          directoryMask = mkOption {
            type = types.str;
            default = "0775";
            description = "Directory creation permission mask.";
          };
          timeMachine = mkOption {
            type = types.bool;
            default = false;
            description = "Enable Apple Time Machine compatibility mode (vfs_fruit).";
          };
          timeMachineMaxSize = mkOption {
            type = types.nullOr types.str;
            default = null;
            example = "512G";
            description = "Quota size limit advertised to Time Machine.";
          };
        };
      });
      default = {};
      description = "Declaratively managed SMB shares.";
    };
  };

  config = mkIf cfg.enable {
    services.samba = {
      enable = true;
      openFirewall = true;
      settings = {
        global = {
          workgroup = cfg.workgroup;
          "server string" = cfg.serverString;
          "netbios name" = cfg.netbiosName;
          security = "user";
          "hosts allow" = concatStringsSep " " cfg.allowedHosts;
          "hosts deny" = "0.0.0.0/0";
          "guest account" = "nobody";
          "map to guest" = "bad user";

          # Apple & ZFS ACL compatibility
          "vfs objects" = "catia fruit streams_xattr acl_xattr";
          "fruit:aapl" = "yes";
          "fruit:metadata" = "stream";
          "fruit:model" = "Macmini";
          "fruit:posix_rename" = "yes";
          "fruit:zero_file_id" = "yes";

          # ACLs and inheritance
          "map acl inherit" = "yes";
          "inherit acls" = "yes";
          "ea support" = "yes";
        };
      } // (mapAttrs' (shareName: shareCfg:
        nameValuePair shareName (
          {
            path = shareCfg.path;
            comment = shareCfg.comment;
            browseable = if shareCfg.browseable then "yes" else "no";
            "read only" = if shareCfg.readOnly then "yes" else "no";
            "guest ok" = if shareCfg.guestOk then "yes" else "no";
            "create mask" = shareCfg.createMask;
            "directory mask" = shareCfg.directoryMask;
          }
          // optionalAttrs (shareCfg.validUsers != []) {
            "valid users" = concatStringsSep " " shareCfg.validUsers;
          }
          // optionalAttrs (shareCfg.forceUser != null) {
            "force user" = shareCfg.forceUser;
          }
          // optionalAttrs (shareCfg.forceGroup != null) {
            "force group" = shareCfg.forceGroup;
          }
          // optionalAttrs shareCfg.timeMachine {
            "vfs objects" = "catia fruit streams_xattr acl_xattr";
            "fruit:time machine" = "yes";
          }
          // optionalAttrs (shareCfg.timeMachine && shareCfg.timeMachineMaxSize != null) {
            "fruit:time machine max size" = shareCfg.timeMachineMaxSize;
          }
        )
      ) (filterAttrs (n: v: v.enable) cfg.shares));
    };

    # Enable Avahi (mDNS / Bonjour) for automatic SMB & Time Machine discovery on macOS/iOS/Windows
    services.avahi = {
      enable = true;
      nssmdns4 = true;
      publish = {
        enable = true;
        userServices = true;
      };
      extraServiceFiles = {
        smb = ''
          <?xml version="1.0" standalone='no'?><!--*-nxml-*-->
          <!DOCTYPE service-group SYSTEM "avahi-service.dtd">
          <service-group>
            <name replace-wildcards="yes">%h (NaxOS SMB)</name>
            <service>
              <type>_smb._tcp</type>
              <port>445</port>
            </service>
            <service>
              <type>_device-info._tcp</type>
              <port>0</port>
              <txt-record>model=RackMac</txt-record>
            </service>
          </service-group>
        '';
      };
    };
  };
}