refactoring to more granular flakes and modules

flakes/common/nix_modules/tmux/default.nix

@@ -0,0 +1,19 @@
+{
+  lib,
+  pkgs,
+  ...
+}:
+{
+  environment.systemPackages = [
+    pkgs.tmux
+  ];
+
+  environment.shellAliases = {
+    tat = "tmux attach-session";
+    t = "tmux";
+  };
+
+  environment.shellInit = lib.concatStringsSep "\n\n" [
+    (builtins.readFile ./tmux_helpers.sh)
+  ];
+}

flakes/common/nix_modules/tmux/tmux_helpers.sh

@@ -0,0 +1,34 @@
+tmux_window () {
+  cmd=${1:-}
+  case "${cmd}" in
+    rename)
+      if [ -z "${2:-}" ]; then
+        tmux setw automatic-rename
+      else
+        tmux rename-window "$2"
+      fi
+      ;;
+    get)
+      printf '%s' "$(tmux display-message -p '#W')"
+      ;;
+    status)
+      out="$(tmux show-window-options automatic-rename 2>/dev/null || true)"
+      if printf '%s' "$out" | grep -q 'automatic-rename on'; then
+        printf 'auto'
+      elif printf '%s' "$out" | grep -q 'automatic-rename off'; then
+        printf 'manual'
+      else
+        # If tmux returns nothing (option not set), default to auto
+        if [ -z "$out" ]; then
+          printf 'auto'
+        else
+          return 1
+        fi
+      fi
+      ;;
+    *)
+      printf 'Usage: tmux_window {rename [NAME]|get|status}\n' >&2
+      return 2
+      ;;
+  esac
+}