Set focus of app running in a terminal.

focusterm.sh

#!/bin/bash

# Focus the window for the current terminal.

# Usage: focusterm

# Supports:
#   X11
#   tmux
#   kitty, westerm, alacrity, and most other terminals

# Requirements:
#   xdotool
#   ps

set -euo pipefail

# Focus the multiplexer pane the shell script is running in.
focus_pane() {
	if [[ -n "$TMUX_PANE" ]]; then
		tmux select-pane -t "$TMUX_PANE"
	fi

	# Focus the Kitty pane the shell script is running in.
	if [[ -n "$KITTY_PANE_ID" ]]; then
		kitty @ focus-window --match id:"$KITTY_WINDOW_ID"
		kitty @ goto-layout --match id:"$KITTY_PANE_ID"
	fi

	# Focus the wezterm pane the shell script is running in.
	if [[ -n "$WEZTERM_PANE" ]]; then
		wezterm cli activate-pane --pane-id "$WEZTERM_PANE"
	fi
}

get_ppid() {
	ps -o ppid= -p "$1" | xargs
}

# Traverse up process tree to find X11 Window
get_window_id() {
	local pid="$1"
	local window_id=""

	while [[ "$pid" != "1" ]] && [[ -z "$window_id" ]]; do
		# get parent pid
		pid="$(get_ppid "$pid")"
		window_id="$(xdotool search --onlyvisible --pid "$pid" 2>/dev/null || true)"
	done

	echo -n "$window_id"
}

# Get the pid of the shell process
get_shell_pid() {
	if [[ -n "$TMUX" ]]; then
		tmux_pid="$(tmux display -p '#{client_pid}')"
		get_ppid "$tmux_pid"
	else
		get_ppid "$$"
	fi
}

main() {
	focus_pane

	# Get the x11 window-id
	if [[ -n "$ALACRITTY_WINDOW_ID" ]]; then
		window_id="$ALACRITTY_WINDOW_ID"
	elif [[ -n "$WINDOW_ID" ]]; then
		window_id="$WINDOW_ID"
	else
		shell_pid="$(get_shell_pid)"
		window_id="$(get_window_id "$shell_pid")"
	fi

	if [[ -n "$window_id" ]]; then
		xdotool windowactivate "$window_id"
	fi
}

main

#TODO:
# WM:
#   WSLg
#   Wayland gdbus
#   Sway
#   Windows
#   Mac
# Multiplexers:
#   Ghostty
#   Terminator
#   Screen