{ pkgs, lib, config, ... }:
let
  capitalizeFirstLetter = str: (lib.strings.toUpper (builtins.substring 0 1 str)) + (builtins.substring 1 (builtins.stringLength str) str);
in
{
  options.frogeye = {
    name = lib.mkOption {
      description = "Name of the system";
      type = lib.types.str;
    };
    toplevel = lib.mkOption {
      description = "top-level flake";
      type = lib.types.attrs;
    };
    cuda = lib.mkEnableOption "Use CUDA for some libraries";
    extra = lib.mkEnableOption "Big software";
    gaming = lib.mkEnableOption "Games";
    polarity = lib.mkOption {
      default = "light";
      description = "Whether to use light theme or dark theme.";
      type = lib.types.enum [ "light" "dark" ];
    };
    desktop = {
      xorg = lib.mkEnableOption "Enable X11 support";
      # TODO Use appropriate OS/HM option(s) instead
      numlock = lib.mkEnableOption "Auto-enable numlock";
      x11_screens = lib.mkOption {
        default = [ "UNSET1" ];
        description = "A list of xrandr screen names from left to right.";
        type = lib.types.listOf lib.types.str;
      };
      maxVideoHeight = lib.mkOption {
        type = lib.types.int;
        description = "Maximum video height in pixel the machine can reasonably watch";
        default = 1080;
      };
      phasesCommands = {
        jour = lib.mkOption { type = lib.types.lines; default = ""; description = "Command to execute for phase: jour"; };
        crepuscule = lib.mkOption { type = lib.types.lines; default = ""; description = "Command to execute for phase: crepuscule"; };
        nuit = lib.mkOption { type = lib.types.lines; default = ""; description = "Command to execute for phase: nuit"; };
      };
    };
    dev = {
      ansible = lib.mkEnableOption "Ansible dev stuff";
      c = lib.mkEnableOption "C/C++ dev stuff";
      docker = lib.mkEnableOption "Docker dev stuff";
      fpga = lib.mkEnableOption "FPGA dev stuff";
      go = lib.mkEnableOption "Go dev stuff";
      node = lib.mkEnableOption "NodeJS dev stuff";
      perl = lib.mkEnableOption "Perl dev stuff";
      php = lib.mkEnableOption "PHP dev stuff";
      prose = lib.mkEnableOption "Writing stuff";
      python = lib.mkEnableOption "Python dev stuff";
      vm = lib.mkEnableOption "Virtual machines";
    };
    storageSize = lib.mkOption {
      default = "small";
      type = lib.types.enum [ "small" "big" "phone" ];
      description = "Type of storage for the device. Used to determine which folder to include.";
    };
    folders = lib.mkOption {
      default = { };
      description = "Folders used by users";
      # Top-level so Syncthing can work for all users. Also there's no real home-manager syncthing module.
      type = lib.types.attrsOf (lib.types.submodule ({ config, name, ... }: {
        options = {
          name = lib.mkOption {
            type = lib.types.str;
            default = name;
            readOnly = true;
            internal = true;
            description = "Name accessing this entry";
          };
          enable = lib.mkOption {
            type = lib.types.bool;
            default = true;
            description = "Whether to use this folder.";
          };
          path = lib.mkOption {
            type = lib.types.str;
            description = "Path relative to HOME. Prefer French names which has more varied initials, easing navigation.";
          };
          label = lib.mkOption {
            type = lib.types.str;
            description = "Friendly name";
            default = capitalizeFirstLetter config.path;
          };
          user = lib.mkOption {
            type = lib.types.str;
            default = "geoffrey";
            description = "User using this directory.";
          };
          fullPath = lib.mkOption {
            type = lib.types.str;
            default = "/home/${config.user}/${config.path}";
            # Hardcoded due to outside of any user context
            description = "Absolute path.";
          };
          xdgUserDirVariable = lib.mkOption {
            type = lib.types.nullOr lib.types.str;
            default = if config.enable then "XDG_${lib.strings.toUpper name}_DIR" else null;
            description = "Name for the XDG user dir variable. If set, will automatically create the directory.";
          };
          syncthing = lib.mkOption {
            default = { };
            description = "Syncthing configuration for the folder";
            type = lib.types.submodule ({ ... }: {
              freeformType = (pkgs.formats.json { }).type;
              options = {
                enable = lib.mkOption {
                  type = lib.types.bool;
                  default = config.enable && config.syncthing.id != null;
                  description = "Whether to sync.";
                };
                id = lib.mkOption {
                  type = lib.types.nullOr lib.types.str;
                  default = null;
                  description = "Syncthing folder id";
                };
              };
            });
          };
          versionsMaxDays = lib.mkOption {
            type = lib.types.nullOr lib.types.int;
            default = 365;
            description = "For big systems, how many days of staggered versions should be kept";
          };
        };
      }));
    };
    hooks.lock = lib.mkOption {
      type = lib.types.lines;
      default = "";
      description = "Bash commands to execute on locking the session.";
    };
    syncthing = {
      id = lib.mkOption {
        type = lib.types.nullOr lib.types.str;
        default = null;
        description = "Full syncthing id";
      };
      name = lib.mkOption {
        type = lib.types.nullOr lib.types.str;
        default = "Geoffrey ${capitalizeFirstLetter config.frogeye.name}";
        description = "Syncthing name";
      };
    };
  };

  config = {
    frogeye = {
      dev = {
        prose = lib.mkDefault true;
        python = lib.mkDefault true;
      };
      folders.download.path = "Téléchargements";
    };
  };
}