#!/bin/bash
#Upgrade go version to 1.7
#wget https://storage.googleapis.com/golang/go1.7.linux-amd64.tar.gz go1.7.tar.gz

function info() {
 echo -e "\033[1;34m$1 \033[0m"
}

function warn() {
 echo -e "\033[0;33m$1 \033[0m"
}

function error() {
 echo -e "\033[0;31m$1 \033[0m"
}

function usage() {
 info "Upgrade or install golang..."
 info "USAGE:"
 info " ./upgrade.sh tar_file gopath"
 info " tar_file specify where is the tar file of go binary file"
 info " gopath specify where is the go workspace, include src, bin, pkg folder"
}

function createGoPath() {
 if [ ! -d $1 ];
 then
 mkdir -p $1
 fi
 if [ ! -d "$1/src" ];
 then
 mkdir "$1/src"
 fi
 if [ ! -d "$1/bin" ];
 then
 mkdir "$1/bin"
 fi
 if [ ! -d "$1/pkg" ];
 then
 mkdir "$1/pkg"
 fi
}

if [ -z $1 ];
then
 usage
 exit 1
fi

file=$1
if [ ! -f $file ];
then
 error "${file} not exist..."
 exit 1
fi

unzipPath="`pwd`/tmp_unzip_path/"
info $unzipPath

if [ ! -d $unzipPath ];
then
 info "not exist"
 mkdir $unzipPath
fi

tar -zxf $file -C $unzipPath

goroot=$GOROOT
if [ ! -n $GOROOT ];
then
 warn "Use default go root /usr/local/go"
 goroot="/usr/local/go"
fi

gopath=$2
info "Create go workspace, include src,bin,pkg folder..."
if [ -z $2 ];
 then
 user=`whoami`
 gopath="/home/$user/workspace/golang"
 warn "Use $gopath as golang workspace..."
 if [ ! -d $gopath ];
 then
 mkdir -p $gopath
 fi
fi

createGoPath $gopath

info "Copy go unzip files to $goroot"
sudo cp -r "$unzipPath/go" $goroot
rm -rf $unzipPath

#etcProfile="/home/user/Desktop/etc"

etcProfile="/etc/profile"
exportGoroot="export GOROOT=$goroot"
if [ ! -z $GOROOT ];
then
 cat $etcProfile | sed 's/^export.GOROOT.*//' | sudo tee $etcProfile > /dev/null
fi
echo $exportGoroot | sudo tee -a $etcProfile

exportGopath="export GOROOT=$gopath"
if [ ! -z $GOPATH ];
then
 cat $etcProfile | sed 's/^export.GOPATH.*//' | sudo tee $etcProfile > /dev/null
fi
echo "export GOPATH=$gopath" | sudo tee -a $etcProfile

echo 'export PATH=$GOROOT/bin:$GOPATH/bin:$PATH' | sudo tee -a $etcProfile

# ## Replace multiple empty lines with one empty line
cat $etcProfile -s | sudo tee $etcProfile > /dev/null

info "To make configuration take effect, will reboot, pls enter[y/n]"
read -p "[y/n]" isReboot
if [ $isReboot = "y" ];
then
 sudo reboot
fi