#!/bin/bash

if [[ $0 != "/bin/bash" ]]; then
  echo "Error: source the script!"
  exit 1
fi

if [[ ! -d $(pwd)/go/bin ]]; then
  echo "Error: go installtion not found in the current directory!"
  return
fi

if [[ -f ./deactivate ]]; then
  echo "Error: already in a vritual enviornment!"
  echo "delete ./deactivate and run again if you are sure!"
  return
fi

# assuming
GOROOT=$(pwd)/go/bin

# delete old deactivate file
rm -f deactivate

# set custom PATH
OLD_PATH=$PATH
export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:$GOROOT

# modify GOPATH
OLD_GOPATH=$GOPATH
export GOPATH=$(pwd)
mkdir -p $GOPATH/src $GOPATH/bin $GOPATH/pkg

echo "export PATH=$OLD_PATH
export GOPATH=$OLD_GOPATH
rm $(pwd)/deactivate" > deactivate
chmod +x deactivate

echo "run \". $(pwd)/deactivate\" to go back to original enviornment"