i3/tmux unified navigation

winnav.sh

#!/usr/bin/env bash

nav() {
  win_name="$(xdotool getactivewindow getwindowname)"
  if [[ "$win_name" =~ ^tmux: ]]; then
    target="$(echo "$win_name" | sed -E 's/^tmux:(.+)/\1:/')"
    pane_at_edge="$(tmux display -t "$target" -p "#{pane_at_$3}")"
    if [[ "$pane_at_edge" =~ "0" ]]; then
      tmux select-pane -t "$target" "-$1"
      return
    fi
  fi
  i3-msg focus "$2"
}

case "$1" in
  down) nav D down bottom ;;
  up) nav U up top ;;
  left) nav L left left ;;
  right) nav R right right ;;
  *) exit 1 ;;
esac