#!/bin/bash

TOTAL_COUNT=`tmux list-sessions | wc -l`
ATTACHED_COUNT=`tmux list-sessions | grep attached | wc -l`

# keep tmux alive after logout
alias tmux="systemd-run --scope --user tmux"

if [ $TOTAL_COUNT -eq $ATTACHED_COUNT ]; then
    tmux
else
    DETACHED_SESSION=`tmux list-sessions -F "#{session_name} #{session_attached}" | grep " 0" | awk '{print $1}' | head -n 1`
    tmux a -t $DETACHED_SESSION
fi