# This module generates nixos-install, nixos-rebuild,
# nixos-hardware-scan, etc.

{config, pkgs, modulesPath, ...}:

let
  ### implementation
  cfg = config.installer;

  makeProg = args: pkgs.substituteAll (args // {
    dir = "bin";
    isExecutable = true;
  });

  nixosBuildVMS = makeProg {
    name = "nixos-build-vms";
    src = ./nixos-build-vms/nixos-build-vms.sh;
  };

  nixosInstall = makeProg {
    name = "nixos-install";
    src = ./nixos-install.sh;

    inherit (pkgs) perl pathsFromGraph;
    nix = config.environment.nix;
    nixpkgsURL = cfg.nixpkgsURL;

    nixClosure = pkgs.runCommand "closure"
      {exportReferencesGraph = ["refs" config.environment.nix];}
      "cp refs $out";
  };

  nixosRebuild = makeProg {
    name = "nixos-rebuild";
    src = ./nixos-rebuild.sh;
  };

  nixosGenSeccureKeys = makeProg {
    name = "nixos-gen-seccure-keys";
    src = ./nixos-gen-seccure-keys.sh;
  };

  nixosHardwareScan = makeProg {
    name = "nixos-hardware-scan";
    src = ./nixos-hardware-scan.pl;
    inherit (pkgs) perl dmidecode;
  };

  nixosOption = makeProg {
    name = "nixos-option";
    src = ./nixos-option.sh;
  };

  nixosGui = pkgs.xulrunnerWrapper {
    launcher = "nixos-gui";
    application = pkgs.stdenv.mkDerivation {
      name = "nixos-gui";
      buildCommand = ''
        cp -r "$gui" "$out"

        # Do not force the copy if the file exists in the sources (this
        # happens for developpers)
        test -e "$out/chrome/content/jquery-1.5.2.js" ||
          cp -f "$jquery" "$out/chrome/content/jquery-1.5.2.js"
      '';
      gui = pkgs.lib.cleanSource "${modulesPath}/../gui";
      jquery = pkgs.fetchurl {
        url = http://code.jquery.com/jquery-1.5.2.min.js;
        sha256 = "8f0a19ee8c606b35a10904951e0a27da1896eafe33c6e88cb7bcbe455f05a24a";
      };
    };
  };

in

{
  options = {

    installer.nixpkgsURL = pkgs.lib.mkOption {
      default = "";
      example = http://nixos.org/releases/nix/nixpkgs-0.11pre7577;
      description = ''
        URL of the Nixpkgs distribution to use when building the
        installation CD.
      '';
    };

    installer.manifests = pkgs.lib.mkOption {
      default = [http://nixos.org/releases/nixpkgs/channels/nixpkgs-unstable/MANIFEST];
      example =
        [ http://nixos.org/releases/nixpkgs/channels/nixpkgs-unstable/MANIFEST
          http://nixos.org/releases/nixpkgs/channels/nixpkgs-stable/MANIFEST
        ];
      description = ''
        URLs of manifests to be downloaded when you run
        <command>nixos-rebuild</command> to speed up builds.
      '';
    };

    installer.enableGraphicalTools = pkgs.lib.mkOption {
      default = false;
      type = with pkgs.lib.types; bool;
      example = true;
      description = ''
        Enable the installation of graphical tools.
      '';
    };

  };

  config = {
    environment.systemPackages =
      [ nixosBuildVMS
        nixosInstall
        nixosRebuild
        nixosHardwareScan
        nixosGenSeccureKeys
        nixosOption
      ] ++ pkgs.lib.optional cfg.enableGraphicalTools nixosGui;

    system.build = {
      inherit nixosInstall nixosHardwareScan nixosOption;
    };
  };
}