#!/usr/bin/env bash
#
# Auto attach to tmux
#

CONF_FILE=$HOME/.autoattach.conf

###########################

function write_setting
{
    if ! sed -i -E "s/^$1=.*/$1=$2/" $CONF_FILE 2> /dev/null; then
        echo "$1=$2" >> $CONF_FILE
    fi
}

function is_tmux_running
{
  if [ -n "${TMUX}" ]; then
		return 0
	fi
  return 1
}

function debug
{
  if ! is_tmux_running; then
    echo $1
  fi
}

function attach_session
{
  if is_tmux_running; then
    exit 0
  fi

	tmux attach -t $1 2> /dev/null

	# Check for exit status
	if [ $? -gt 0 ]; then
		echo "There is no tmux session '$1'"
		if [ -z "${AUTO_CREATE}" ]; then
      read -p "Do you want me to auto create sessions by default? [Y/n]: "
      # convert to lowercase, then match
      if [ "${REPLY,,}" = "y" -o -z "${REPLY}" ]; then
        write_setting 'AUTO_CREATE' '1'
        AUTO_CREATE=1
      else
        write_setting 'AUTO_CREATE' '0'
      fi
    fi

    if [ "${AUTO_CREATE}" = "1" ]; then
      tmux new-session -s $1 2> /dev/null
      exit 0
    fi

    echo 'Nothing to do, exiting...'
    exit 1

	fi
}

function usage
{
	echo "Usage: ${0}"
	echo "    -c | --clear"
	echo "        Delete configuration file"
	echo "    -s | --set auto_create on"
	echo "        Set configuration variable"
	echo "          auto_create on/off"
	echo "            Auto create session on start if session is missing"
	echo "    -h | --help"
	echo "        Show this usage"

	exit 0
}

# Load configuration file
test -f $CONF_FILE && . $CONF_FILE

# Detect platform
PLATFORM='unknown'
unamestr=$(uname)
case "$unamestr" in
	OpenBSD* )
		debug "*BSD OS detected!!"
		debug "Long options is disabled!!"
		OPTS=`getopt	chgs: $*`
		set_opts_exit_status=$?
		PLATFORM=$unamestr ;;
		#if [	$? -ne 0 ]; then
		 #  echo	'Usage:	...'
		  # exit	2
	   	#fi
	* )
		OPTS=$(getopt -o chgs: -l clear,help,set:,get: -n 'autoattach' -- "$@")
		set_opts_exit_status=$?
		PLATFORM='Linux' ;;
esac

if [ "$set_opts_exit_status" -gt '0' ]; then
    echo 'Failed to set command line arguments'
    exit 1;
fi

eval set -- "$OPTS"

CLEAR=false
SET=false
while true; do
	case "$1" in
		-c | --clear ) CLEAR=true; shift ;;
		-s | --set )
            case "$2" in
                'auto_create' )
                    case "$4" in
                        'on' )
                            echo 'Setting auto_create to 1'
                            write_setting 'AUTO_CREATE' '1'
                            shift;;
                        'off' )
                            echo 'Setting auto_create to 0'
                            write_setting 'AUTO_CREATE' '0'
                            shift;;
                    esac

                    shift;;
                *)
                    echo "Failed to set configuration $2 $4"
                    exit 1
            esac
            exit 0
            shift ;;
		-h | --help ) usage; shift ;;
		-- ) shift; break ;;
		* ) break ;;
	esac
done

# Clear default window
if [ $CLEAR = true ]; then
	echo "Deleting configuration..."
	rm -f $CONF_FILE
	exit 0
fi

if [ -n "${SET}" -a $SET != false ]; then
    echo "Updating configuration..."
	write_setting $SET
	exit 0
fi

# Check if this a drop down terminal from env
if [ -n "${DROP_DOWN_TERMINAL}" ]; then
    attach_session drop_down
else
    attach_session regular
fi