{ user ? throw "user argument is required" }: { config, pkgs, ... }:

let
  hmConfig = config.home-manager.users."${user.name}";
in {
  home-manager.users."${user.name}" = {
    programs.git = {
      enable = true;
      lfs.enable = true;
      userName = user.fullName;
      userEmail = user.email;
      signing = {
        signByDefault = true;
        key = null;
      };
      extraConfig.credential.helper = "store";
      hooks = let
        commit-msg-hook = pkgs.writeShellScriptBin "git-commit-msg" ''
          ${pkgs.git}/bin/git interpret-trailers --if-exists doNothing --trailer \
            "Signed-off-by: $(git config user.name) <$(git config user.email)>" \
            --in-place "$1"
        '';
      in {
        commit-msg = "${commit-msg-hook}/bin/git-commit-msg";
      };
    };

    sops.secrets."git".path = "${hmConfig.xdg.configHome}/git/credentials";
  };
}