#!/bin/sh

if [ -n "$SSH_CLIENT" ] || [ -n "$SSH_TTY" ]; then
	tmux_sock=$(tmux display -p "#{socket_path}")
	tmux -S "${tmux_sock}.control" run-shell "$(basename "$0") $*"
	exit 0
fi

HOST=$(tmux display -p '#h' 2>/dev/null)
ATTACHED=$(tmux display -p "#{?#{m:*ssh,#{socket_path}},#{s/_/./:session_name},#{host}}")

sessions() {
	{
		tmux -L ssh ls -F '#{?session_last_attached,#{session_last_attached},#{session_created}}:#{s/_/./:session_name}'
		tmux ls -F '#{?session_last_attached,#{session_last_attached},#{session_created}}:#{host}'
	} 2>/dev/null | sort -u | cut -d':' -f2
}

if [ "$#" -eq 0 ]; then
	set -- "$(
		sessions | sshr --resolve --port 22 --scan 0.0.0.0/24 --exclude "$ATTACHED" --include - |
			fzf-tmux -p20%,20% -- --print-query |
			tail -1
	)"
elif [ "$1" = "-1" ] 2>/dev/null; then
	set -- "$(sessions | sed "/$ATTACHED/d" | head -n1)"
fi

if [ -z "$1" ]; then
	exit 0
fi

while read -r k v; do
	case "$k" in
	"hostname")
		hostname=$v
		session=$(printf '%s' "$v" | tr '.' '_')
		break
		;;
	esac
done <<-EOF
	 $(ssh -G "$@")
EOF

if [ "${hostname##"$HOST"}" != "$hostname" ]; then
	tmux detach -E 'tmux new -A'
else
	if ! tmux -L ssh has-session -t "$session" 2>/dev/null; then
		tmux -L ssh new-session -ds "$session" -- \
			ssh -t "$@" \
			-R "/tmp/tmux-${HOST}.control:/tmp/tmux-%i/ssh" \
			-- "zsh -l -c 'tmux -S /tmp/tmux-${HOST} new -A'"
	fi

	if [ -z "$TMUX" ]; then
		tmux -L ssh attach -t "$session"
	else
		tmux detach -E "tmux -L ssh attach -t $session"
	fi

	exit 0
fi