chore(home-manager/gpg-agent): template agent configuration from upstream dotfiles

users/transcaffeine/home-manager/gnupg.nix

@@ -1,10 +1,14 @@
-{ lib, ... }: {
-  programs.gpg = let
+{ lib, ... }:
+
+let
   repo = (builtins.fetchGit {
         url = "https://git.finally.coffee/transcaffeine/dotfiles.git";
         ref = "main";
         shallow = true;
   });
+  utils = import ../../../utils { inherit lib; };
+in {
+  programs.gpg = let
     gpgconf = builtins.listToAttrs (
       map (entry: {
           name = toString (lib.sublist 0 1 (lib.splitString " " entry));
@@ -21,4 +25,32 @@
     enable = true;
     settings = gpgconf;
   };
+  services.gpg-agent = let
+    gpg_agent_config = builtins.listToAttrs (
+      map (entry: let
+        val = toString (lib.sublist 1 100 (lib.splitString " " entry));
+        emptyStringToTrue = (x: if lib.isBool x then x else if x == "" then true else x);
+      in {
+        name = toString (lib.sublist 0 1 (lib.splitString " " entry));
+        value = emptyStringToTrue val;
+      }) (
+        builtins.filter (v: v != "") (
+          lib.splitString "\n" (
+            lib.readFile (repo.outPath + "/config/gnupg/gpg-agent.conf")
+          )
+        )
+      )
+    );
+  in {
+    enable = true;
+    enableSshSupport = gpg_agent_config."enable-ssh-support";
+    defaultCacheTtl = gpg_agent_config."default-cache-ttl";
+    maxCacheTtl = gpg_agent_config."max-cache-ttl";
+    defaultCacheTtlSsh = gpg_agent_config."default-cache-ttl-ssh";
+    maxCacheTtlSsh = gpg_agent_config."max-cache-ttl-ssh";
+    extraConfig = utils.attrsToConfig {
+      "ignore-cache-for-signing" = gpg_agent_config."ignore-cache-for-signing";
+      "no-allow-external-cache" = gpg_agent_config."no-allow-external-cache";
+    };
+  };
 }

utils/default.nix

@@ -0,0 +1,14 @@
+{ lib, ...}:
+
+rec {
+  _tupleToEntry = x: x.name + (if lib.isBool x.value then "" else (" " + x.value));
+  attrsToConfig = attrs: (
+    lib.concatStringsSep "\n" (
+      map (_tupleToEntry) (
+        builtins.filter (e: e.value != false) (
+          lib.attrsToList attrs
+        )
+      )
+    )
+  );
+}