modularize git

modules/options/accounts/default.nix

@@ -4,6 +4,24 @@
   ...
 }: let
   inherit (lib) mkOption types;
+
+  sshKeys = {
+    cnixpad = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIXCjkKouZrsMoswMIeueO8X/c3kuY3Gb0E9emvkqwUv cnst@cnixpad";
+    cnixlab = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAICiNcNex+/hrEQJYJJTj89uPXocSfChU38E5TujWdxaM cnstlab@cnixlab";
+    cnixtop = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIEUub8vbzUn2f39ILhAJ2QeH8xxLSjiyUuo8xvHGx/VB adam@cnst.dev";
+    toothpc = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGu5vZbb5ExampleKeyHereGfDF9c5 toothpick@toothpc";
+  };
+
+  keyName = config.accounts.sshUser or null;
+
+  selectedKey =
+    if keyName != null
+    then
+      lib.attrByPath [keyName] (
+        builtins.abort "No SSH key defined for hostname/key '${toString keyName}'"
+      )
+      sshKeys
+    else builtins.abort "No accounts.sshUser provided, cannot select SSH key.";
 in {
   options.accounts = {
     username = mkOption {
@@ -11,10 +29,21 @@ in {
       default = "cnst";
       description = "Set the desired username";
     };
-    hostname = mkOption {
+    mail = mkOption {
       type = types.str;
-      default = "cnix";
-      description = "Set the desired hostname";
+      default = "adam@cnst.dev";
+      description = "Set the desired email";
+    };
+    sshKey = lib.mkOption {
+      type = lib.types.str;
+      default = selectedKey;
+      description = "Host-specific SSH key";
+      readOnly = true;
+    };
+    sshUser = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      description = "Optional override for selecting an SSH key by name";
     };
   };
 }