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

with lib;

let
  cfg = config.hardware.uconsole-cm5-aio-v2;

  # GPIO pin map matching the AIO v2 board hardware
  #   SDR  (RTL-SDR):  GPIO 7
  #   LoRa (SX1262) :  GPIO 16
  #   USB Hub Interne: GPIO 23
  #   GPS (GNSS)    :  GPIO 27
  gpioMap = {
    GPS  = 27;
    LORA = 16;
    SDR  = 7;
    USB  = 23;
  };

  # Generate a script that applies boot rail states via pinctrl
  applyRailsScript = pkgs.writeShellScript "apply-aio-v2-rails" (
    ''
      set -e
      PINCTRL=${pkgs.libraspberrypi}/bin/pinctrl
    ''
    + concatStringsSep "" (mapAttrsToList (name: pin: ''
      if [ "${if cfg.bootRails.${name} then "1" else "0"}" = "1" ]; then
        echo "AIO v2: ${name} (GPIO${toString pin}) → ON"
        $PINCTRL set ${toString pin} op dh
      else
        echo "AIO v2: ${name} (GPIO${toString pin}) → OFF"
        $PINCTRL set ${toString pin} op dl
      fi
    '') gpioMap)
  );

  # aiov2_ctl CLI tool — fetched from GitHub, available as `aiov2_ctl`
  aiov2CtlPkg = pkgs.stdenv.mkDerivation rec {
    pname = "aiov2_ctl";
    version = "0-unstable-2026-06-16";

    src = pkgs.fetchFromGitHub {
      owner = "hackergadgets";
      repo = "aiov2_ctl";
      rev = "main";
      hash = "sha256-ddffc50568fb082340283ab4acb58d22ddbf429985a71f1804a6ca1deb455289";
    };

    dontUnpack = true;

    installPhase = ''
      mkdir -p $out/bin $out/share/aiov2_ctl/img
      cp $src/aiov2_ctl.py $out/bin/aiov2_ctl
      chmod +x $out/bin/aiov2_ctl
      patchShebangs $out/bin/aiov2_ctl
      substituteInPlace $out/bin/aiov2_ctl \
        --replace-fail '"/usr/local/share/aiov2_ctl/img/' '"'$out'/share/aiov2_ctl/img/'
      cp -r $src/img/* $out/share/aiov2_ctl/img/
    '';

    meta = {
      description = "HackerGadgets uConsole AIO v2 GPIO control and telemetry tool";
      homepage = "https://github.com/hackergadgets/aiov2_ctl";
      license = lib.licenses.mit;
      maintainers = with lib.maintainers; [ ];
      platforms = [ "aarch64-linux" ];
    };
  };
in {
  options.hardware.uconsole-cm5-aio-v2 = {
    enable = mkEnableOption "HackerGadgets uConsole AIO v2 board support";

    bootRails = {
      GPS = mkOption {
        type = types.bool;
        default = false;
        description = "Enable GPS module at boot (GPIO 27)";
      };
      LORA = mkOption {
        type = types.bool;
        default = false;
        description = "Enable LoRa module at boot (GPIO 16)";
      };
      SDR = mkOption {
        type = types.bool;
        default = false;
        description = "Enable SDR module at boot (GPIO 7)";
      };
      USB = mkOption {
        type = types.bool;
        default = false;
        description = "Enable internal USB hub at boot (GPIO 23)";
      };
    };

    package = mkOption {
      type = types.package;
      default = aiov2CtlPkg;
      defaultText = literalExpression "aiov2CtlPkg";
      description = "aiov2_ctl package to use";
    };

    enableGPS = mkOption {
      type = types.bool;
      default = false;
      description = ''
        Enable GPS UART (/dev/ttyAMA0 at 9600 baud).
        Requires enabling UART on the CM5 via boot.kernelParams.
      '';
    };

    enableGUI = mkOption {
      type = types.bool;
      default = false;
      description = ''
        Enable the system tray GUI for aiov2_ctl.
        Requires a desktop environment with system tray support.
      '';
    };
  };

  config = mkIf cfg.enable {
    # Package the aiov2_ctl tool + pinctrl
    environment.systemPackages = with pkgs; [
      cfg.package
      libraspberrypi      # provides pinctrl
    ];

    # Boot rail systemd oneshot service
    systemd.services.aiov2-rails-boot = {
      description = "Apply AIO v2 GPIO rail boot states";
      after = [ "local-fs.target" ];
      wants = [ "local-fs.target" ];
      before = [ "multi-user.target" ];
      wantedBy = [ "multi-user.target" ];
      serviceConfig = {
        Type = "oneshot";
        ExecStart = "${applyRailsScript}";
        RemainAfterExit = true;
      };
    };

    # GPS configuration
    boot.kernelParams = mkIf cfg.enableGPS [ "uart0=on" ];

    users.users = mkIf cfg.enableGPS {
      gortium = {
        extraGroups = [ "dialout" ];
      };
    };

    # GUI autostart (XDG)
    systemd.user.services.aiov2-ctl-gui = mkIf cfg.enableGUI {
      description = "AIO v2 System Tray Controller";
      after = [ "graphical-session.target" ];
      wants = [ "graphical-session.target" ];
      wantedBy = [ "graphical-session.target" ];
      serviceConfig = {
        Type = "simple";
        ExecStart = "${cfg.package}/bin/aiov2_ctl --gui";
        Restart = "on-failure";
        RestartSec = 5;
      };
      environment = {
        AIOV2_CTL_DEBUG = "0";
      };
    };
  };
}