#/usr/bin/bash
if [ ! -d $1 ]; then
  echo "  usage: flip dir-name"
  echo "    will flip a t-dirme to xt-dirname and back"
  exit
fi

if [[ $1 =~ ^xt-(.*)$ ]]; then
  filename="t-${BASH_REMATCH[1]}"
  echo "  swich broken dir $1 back to normal dir $filename"
fi
if [[ $1 =~ ^t-(.*)$ ]]; then
  filename="xt-${BASH_REMATCH[1]}"
  echo "  swich normal dir $1 to broken dir $filename"
fi

if [ -d $filename ]; then
  echo "  target dir $filename already exist, abort"
  exit
fi

echo "  mv $1 $filename"
mv $1 $filename