feat: nixos module is configurable now

assets/pkg/nix/make-cfg.nix

@@ -0,0 +1,70 @@
+{ lib, keys-h-file }:
+
+let
+    double-match-to-nameval = dmatch: { name = builtins.elemAt dmatch 0; value = builtins.elemAt dmatch 1; };
+
+    keys-enum = let
+        key-names = builtins.replaceStrings ["\n" " "] ["" ""] (
+            builtins.elemAt (
+                builtins.match
+                    ".*KEY_NAMES\\[][[:blank:]]*=[[:blank:]]*\\{([^}]*)}.*"
+                    keys-h-file
+            ) 0
+        );
+
+        keys-2d-list = builtins.map
+            (builtins.match "\\[(.*)]=\"(.*)\"")
+            (builtins.filter
+                (s: builtins.isString s && s != "")
+                (builtins.split "," key-names)
+            );
+
+    in builtins.listToAttrs (
+        builtins.map
+            (k: k // { value = { __enum_key = k.value; }; })
+            (builtins.map double-match-to-nameval keys-2d-list)
+    );
+in {
+    inherit keys-enum;
+    make = let
+        name-val-to-attrs = (name: value: { inherit name value; } );
+        map-attrs = attrset: fn: lib.map fn
+            (lib.attrsets.mapAttrsToList name-val-to-attrs attrset);
+
+        try-foldl' = op: nul: list:
+            if (builtins.length list) == 0 then ""
+            else builtins.foldl' op nul list;
+        concat-with = sepr: list: try-foldl'
+            (x: y: if x == null then y else x + sepr + y)
+            null
+            list;
+
+        ser-bool = bool: if bool then "true" else "false";
+        ser-str = str: "\"${builtins.replaceStrings ["\n" "\""] ["\\n" "\\\""] str}\"";
+        ser-kvs = { name, value }: if builtins.isList value then
+            concat-with "\n" (
+                builtins.map
+                    (value: ser-kvs { inherit name value; })
+                    value
+            )
+        else "${name} = ${
+            if builtins.isString value then
+                ser-str value
+            else if builtins.isInt value then
+                builtins.toString value
+            else if builtins.isBool value then
+                ser-bool value
+            else if builtins.isAttrs value then
+                value.__enum_key
+            else builtins.throw "type not supported"
+        }";
+
+        ser-table = table': let
+            tname = table'.name;
+            table = table'.value;
+        in
+        "[${tname}]\n" + (
+            concat-with "\n" (map-attrs table ser-kvs)
+        );
+    in cfg: concat-with "\n\n" (map-attrs cfg ser-table);
+}