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

let cfg = config.eb.boot;
in {
  options.eb.boot = {
    type = mkOption {
      description = "Type of boot. Default bios.";
      default = null;
      type = types.enum [ "bios" "uefi" ];
    };

    qemu = mkOption {
      description = "Set to true if running in qemu";
      default = false;
      type = types.bool;
    };

    grubInstallDevice = mkOption {
      description = "The disk to install Grub to";
      type = types.nullOr types.str;
      default = null;
    };
  };

  config = mkMerge [
    {

      fileSystems."/" = {
        device = "/dev/disk/by-label/nixos";
        fsType = "ext4";
      };

      swapDevices = [{ device = "/dev/disk/by-label/swap"; }];
    }
    (mkIf (cfg.type == "bios") {
      boot.loader = {
        grub = {
          enable = true;
          version = 2;
          device = cfg.grubInstallDevice;
          efiSupport = false;
          useOSProber = true;
          extraEntries = ''
            menuentry "Reboot" {
              reboot
            }
            menuentry "Power off" {
              halt
            }
          '';
        };
      };

    })
    (mkIf (cfg.type == "uefi") {
      boot.loader = {
        systemd-boot = {
          enable = true;
          editor = false;
          configurationLimit = 10;
        };

        efi.canTouchEfiVariables = true;
      };

      fileSystems."/boot" = {
        device = "/dev/disk/by-label/boot";
        fsType = "vfat";
      };
    })
    (mkIf (cfg.qemu) {
      boot.initrd.postDeviceCommands = ''
        # Set the system time from the hardware clock to work around a
        # bug in qemu-kvm > 1.5.2 where the VM clock is initialized
        # to the *boot time* of the host.
        hwclock -s
      '';

      services.qemuGuest.enable = true;
    })
  ];
}