refactor some stuff

etcnixos/common.nix

@@ -198,8 +198,20 @@
     libmtp
   ];
 
-  #wayland with electron/chromium applications
+  # wayland with electron/chromium applications
   environment.sessionVariables.NIXOS_OZONE_WL = "1";
 
+  # https://nixos.wiki/wiki/Fish#Setting_fish_as_your_shell
+  programs.fish.enable = true;
+  programs.bash = {
+    interactiveShellInit = ''
+      if [[ $(${pkgs.procps}/bin/ps --no-header --pid=$PPID --format=comm) != "fish" && -z ''${BASH_EXECUTION_STRING} ]]
+      then
+        shopt -q login_shell && LOGIN_OPTION='--login' || LOGIN_OPTION=""
+        exec ${pkgs.fish}/bin/fish $LOGIN_OPTION
+      fi
+    '';
+  };
+
   system.stateVersion = "24.11";
 }