niksos/modules/other/hardware.nix

{
    config,
    lib,
    ...
}: let
    cfg = config.poz.other.hardware;

    inherit (lib.attrsets) mapAttrsToList;
    inherit (lib.modules) mkIf;
    inherit (lib.options) mkOption;
    inherit (lib.types) attrsOf float int submodule;
    inherit (lib.types.ints) positive;
in {
    options.poz.other.hardware = {
        monitors = mkOption {
            description = "hostname for this system";
            type = attrsOf (submodule {
                options = {
                    resolution = mkOption {
                        description = "monitor resolution";
                        type = submodule {
                            options = {
                                w = mkOption {
                                    description = "monitor width";
                                    type = positive;
                                };
                                h = mkOption {
                                    description = "monitor height";
                                    type = positive;
                                };
                            };
                        };
                    };
                    refreshRate = mkOption {
                        description = "monitor refresh rate";
                        type = positive;
                    };
                    position = mkOption {
                        description = "monitor position";
                        type = submodule {
                            options = {
                                x = mkOption {
                                    description = "monitor x position";
                                    type = int;
                                };
                                y = mkOption {
                                    description = "monitor y position";
                                    type = int;
                                };
                            };
                        };
                    };
                    scale = mkOption {
                        description = "monitor scale";
                        type = float;
                    };
                };
            });
            default = {};
        };
    };

    config = mkIf (cfg.monitors != {}) {
        boot.kernelParams = mapAttrsToList (name: m: let
            xres = toString m.resolution.w;
            yres = toString m.resolution.h;
            refresh = toString m.refreshRate;
        in
            # https://www.kernel.org/doc/html/latest/fb/modedb.html
            "video=${name}:${xres}x${yres}@${refresh}"
        ) cfg.monitors;
    };
}