Use the name of the remote host for tmux window when running ssh

ssh() {
    # ssh wrapper function to set tmux window (pane?) title

    # bypass this function if stdout is not a terminal, to avoid messing up
    # the output with our printf() calls.
    [[ -t 1 ]] || exec command ssh $@

    local prev_window_name=$(tmux display-message -p "#{window_name}")
    local prev_pane_title=$(tmux display-message -p "#{pane_title}")
    local hostname=$(perl -e 'if (length(@ARGV) == 1) { print $ARGV[0]; exit; } else { foreach $h (@ARGV) { if ($h =~ /[a-z\._-]+\.[a-z]{2,}/) { print $h; exit; } } }' -- $@)

    if [[ -z $hostname ]]; then
        command ssh $@
    else
        # Set window name and pane title when there's only 1 pane (i.e. the whole window),
        # otherwise set just the pane title.
        if [[ $(tmux display-message -p "#{window_panes}") == 1 ]]; then
            printf "\033k${hostname}\033\\"
            printf "\033]2;${hostname}\033\\"
        else
            printf "\033]2;${hostname}\033\\"
        fi
        command ssh $@
        if [[ $(tmux display-message -p "#{window_panes}") == 1 ]]; then
            printf "\033k${prev_window_name}\033\\"
        fi
        printf "\033]2;${prev_pane_title}\033\\"
    fi
}