Add opt-in theme sync to herdr machines (#13430)

* Add a theme-set sample hook that mirrors themes to herdr machines

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Mirror theme changes to herdr machines by default

Replaces the sample hook with omarchy-theme-sync, which omarchy-theme-set
starts detached after every theme change, and a theme-sync-off toggle that
stops a machine from both sending and receiving.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Rename omarchy-theme-sync to omarchy-theme-set-herdr-machines

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Label the toggle Herdr Theme Sync and extract its menu guard

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Answer the Herdr Theme Sync menu guard from omarchy-theme-set-herdr-machines

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Sync herdr machines one at a time and drop the dry run

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Check the theme sync toggle under the lock and stop special-casing this machine

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Make herdr theme sync opt-in

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

bin/omarchy-theme-set

@@ -441,6 +441,9 @@ if [[ $THEME_HEADLESS != "1" ]]; then
   # Call hook on theme set
   omarchy-hook theme-set "$THEME_NAME" >/dev/null
 
+  # Mirror the theme to herdr machines. SSH can take a while, so this never holds up the theme change.
+  setsid omarchy-theme-set-herdr-machines >>"$HOME/.local/state/omarchy/theme-set-herdr-machines.log" 2>&1 </dev/null &
+
   # Warm the background selector's thumbnails. The theme picker keeps its own
   # rows in the shell and refreshes them each time it opens.
   omarchy-theme-bg-cache >/dev/null 2>&1 &

bin/omarchy-theme-set-herdr-machines

@@ -0,0 +1,75 @@
+#!/bin/bash
+
+# omarchy:summary=Mirror the current theme to your herdr machines that run Omarchy
+# omarchy:args=[--available]
+# omarchy:hidden=true
+
+# omarchy-theme-set runs this in the background after every theme change. Sync is off until
+# the herdr-theme-sync toggle is turned on, and a machine only accepts themes with it on too.
+
+# Columns: id, label, SSH target, session, state.
+# This machine may be listed too, and it is already on the theme, so it needs no special case.
+targets=$(herdr machine list 2>/dev/null | awk -F '\t' '$5 == "enabled" { print $3 }')
+
+# The menu offers the toggle whenever there is a machine to sync to, whether or not sync is on.
+if [[ $1 == "--available" ]]; then
+  [[ -n $targets ]]
+  exit
+fi
+
+# Serialize runs and send whichever theme is current once the lock is held,
+# so a slow earlier run can never overwrite a later theme change.
+exec 9>"${XDG_RUNTIME_DIR:-/tmp}/omarchy-theme-set-herdr-machines.lock"
+flock 9
+
+# A theme that arrived from another machine stops here, so machines never echo it back.
+# The toggle is checked once the lock is held, so turning sync off also stops a queued run.
+if [[ -n $OMARCHY_THEME_SYNC_FROM ]] || ! omarchy-toggle-enabled herdr-theme-sync; then
+  exit 0
+fi
+
+theme=$(cat "$HOME/.local/state/omarchy/current/theme.name" 2>/dev/null)
+
+# Runs on the remote machine under a login shell, so OMARCHY_PATH and PATH are set there.
+# SSH carries no desktop session, so the environment comes from the live Hyprland instance.
+# The flag is read directly, so an Omarchy that predates theme sync simply counts as off.
+# Braces make bash read the whole script before running it, so nothing it runs can consume the rest.
+read -r -d '' REMOTE_SCRIPT <<'EOF'
+{
+  if [[ ! -f ~/.local/state/omarchy/toggles/herdr-theme-sync ]]; then
+    echo "theme sync is off"
+    exit
+  fi
+
+  if [[ $(cat ~/.local/state/omarchy/current/theme.name 2>/dev/null) == "$theme" ]]; then
+    echo "already on $theme"
+    exit
+  fi
+
+  export XDG_RUNTIME_DIR="/run/user/$(id -u)"
+  instance=$(hyprctl instances -j 2>/dev/null | jq -r 'max_by(.time) // empty | "\(.instance) \(.wl_socket)"')
+  if [[ -z $instance ]]; then
+    echo "no Hyprland session"
+    exit
+  fi
+
+  read -r HYPRLAND_INSTANCE_SIGNATURE WAYLAND_DISPLAY <<<"$instance"
+  export HYPRLAND_INSTANCE_SIGNATURE WAYLAND_DISPLAY
+  export DBUS_SESSION_BUS_ADDRESS="unix:path=$XDG_RUNTIME_DIR/bus"
+  export OMARCHY_THEME_SYNC_FROM="$from"
+
+  if omarchy theme set "$theme" >/dev/null 2>&1; then
+    echo "set $theme"
+  else
+    echo "failed to set $theme"
+  fi
+} </dev/null
+EOF
+
+# One machine at a time, so an SSH agent like 1Password asks for approval at most once.
+# SSH joins its arguments into a shell command, so the theme travels on stdin as a quoted assignment.
+for target in $targets; do
+  result=$(printf 'theme=%q from=%q\n%s\n' "$theme" "$(hostname)" "$REMOTE_SCRIPT" |
+    timeout 60 ssh -o BatchMode=yes -o ConnectTimeout=5 "$target" bash -l -s 2>&1 | tail -n 1)
+  echo "$(date '+%F %T') $target: ${result:-unreachable}"
+done

bin/omarchy-toggle-theme-sync

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+# omarchy:summary=Toggle mirroring theme changes to and from your herdr machines
+
+omarchy-toggle herdr-theme-sync
+
+if omarchy-toggle-enabled herdr-theme-sync; then
+  omarchy-notification-send -g 󰸌 "Herdr theme sync enabled"
+else
+  omarchy-notification-send -g 󰸌 "Herdr theme sync disabled"
+fi