Create home-manager module for packer

2024-04-12 12:51:08 +02:00
parent 08a823cb06
commit ffab35d8fb
4 changed files with 142 additions and 59 deletions
--- a/hm.module.nix
+++ b/hm.module.nix
@@ -0,0 +1,101 @@
+flake: {
+  config,
+  pkgs,
+  lib,
+  system,
+  ...
+}: let
+  cfg = config.programs.packer;
+  templatePath = "${config.home.homeDirectory}/.config/packer/template.clj";
+
+  app = pkgs.runCommand "packer" {buildInputs = [pkgs.makeWrapper];} ''
+    makeWrapper ${flake.outputs.packages.${system}.packer}/bin/packer $out/bin/packer --set PACKER_TEMPLATE_FILE "${templatePath}"
+  '';
+in {
+  options.programs.packer = with lib; {
+    enable = mkEnableOption "Packer application";
+
+    templateFile = mkOption {
+      type = types.nullOr types.path;
+      description = "The path to template file. If provided, the 'template' option will be ignored.";
+      default = null;
+      example = "./packer.template.clj";
+    };
+
+    template = mkOption {
+      type = types.str;
+      description = "The content of the template file written in Clojure language.";
+      default = ''
+        (use 'packer.model)
+        (require 'packer.util)
+
+        ; Define some useful function
+        ; to provide a constant number of items.
+        (defn x [n] (fn [_] n))
+
+        ; Define a store - the single source
+        ; of truth of all items from which
+        ; we are going to choose what we want to pack.
+        ; The items are grouped by categories.
+        (def store {
+          :cloths [
+            (->Item :t-shirt #(/ % 4))
+          ]
+
+          :electronics [
+            (->Item :smartphone (x 1))
+            (->Item :tablet (x 1))
+            (->Item :laptop (x 1))
+          ]
+        })
+
+        ; Define the display names for each
+        ; item, category and question.
+        (def i18n {
+          :nights? "How many nights?"
+          :tablet? "Do you need your tablet there?"
+          :laptop? "Do you need your laptop there?"
+          :electronics "Electronics"
+          :cloths "Cloths"
+          :t-shirt "T-shirt"
+          :smartphone "Smartphone"
+          :tablet "Tablet"
+          :laptop "Laptop"
+        })
+
+        ; Define some utility function
+        ; to generate preset basing on some question
+        (defn preset [question items seq]
+          (if (packer.util/ask-bool (get i18n question))
+            (concat seq items)
+            seq))
+
+        ; Define profile - a function which takes
+        ; a number of provided nights and produces
+        ; the sequence of all items which should
+        ; be in the target list. If the sequence is empty
+        ; no item will be produced on the target list.
+        (defn profile [nights]
+          (->> [:smartphone :t-shirt]
+              (preset :tablet? [:tablet])
+              (preset :laptop? [:laptop])))
+
+        ; Wrap it up together. It should be
+        ; the last expression in the file.
+        (->Template store i18n profile)
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    home.packages = [app];
+    home.file.${templatePath} =
+      if (cfg.templateFile != null)
+      then {
+        source = cfg.templateFile;
+      }
+      else {
+        text = cfg.template;
+      };
+  };
+}