nix-git/modules/gnome-profile-image.nix

{ config, pkgs, ... }:
let
  iconsDir =  "/var/lib/AccountsService/icons";
  usersDir = "/var/lib/AccountsService/users";
  user = "yoda";
in
{
  # https://discourse.nixos.org/t/setting-the-user-profile-image-under-gnome/36233/4

  # Important: File permissions and file format
  # https://discourse.nixos.org/t/setting-the-user-profile-image-under-gnome/36233/7

  # https://github.com/tolgaerok/nixos-kde/blob/3c4b55f2b0345facc5bc5157750dfaecef9d4d6c/machines/LAPTOPS/HP-i5-ProBook-6460b/user/user-profile-pic/default.nix
  # https://github.com/tolgaerok/nixos-kde/blob/3c4b55f2b0345facc5bc5157750dfaecef9d4d6c/user/user-home-settings/create-user-profile-pics.nix

  # After changing my profile image in KDE Plasma 6, this file was created:
  #   /var/lib/AccountsService/users/yoda
  # With content:
  #   [User]
  #   Icon=/var/lib/AccountsService/icons/yoda
  #   SystemAccount=false
  # Permissions: root:root 0600
  # This file is required, thus we create it manually in this nix config.

  # `system.activationScripts`:
  # - Since these are executed every time you boot the system or run `nixos-rebuild`, it’s important that they are idempotent and fast.
  system.activationScripts.setGnomeProfilePicture = ''
    mkdir -p ${iconsDir}
    cp ${(pkgs.callPackage ./profile-image.nix { })}/img.png ${iconsDir}/${user}

    mkdir -p ${usersDir}
    rm -f ${usersDir}/${user}
    echo "[User]" >> ${usersDir}/${user}
    echo "Icon=${iconsDir}/${user}" >> ${usersDir}/${user}
    echo "SystemAccount=false" >> ${usersDir}/${user}
  '';
}