#!/bin/bash

GVM_SERVICE="http://get.gvmtool.net"
PLATFORM=$(uname)

echo '                                                                     '
echo 'Thanks for using                                                     '
echo '                                                                     '
echo '_____/\\\\\\\\\\\\__/\\\________/\\\__/\\\\____________/\\\\_        '
echo ' ___/\\\//////////__\/\\\_______\/\\\_\/\\\\\\________/\\\\\\_       '
echo '  __/\\\_____________\//\\\______/\\\__\/\\\//\\\____/\\\//\\\_      '
echo '   _\/\\\____/\\\\\\\__\//\\\____/\\\___\/\\\\///\\\/\\\/_\/\\\_     '
echo '    _\/\\\___\/////\\\___\//\\\__/\\\____\/\\\__\///\\\/___\/\\\_    '
echo '     _\/\\\_______\/\\\____\//\\\/\\\_____\/\\\____\///_____\/\\\_   '
echo '      _\/\\\_______\/\\\_____\//\\\\\______\/\\\_____________\/\\\_  '
echo '       _\//\\\\\\\\\\\\/_______\//\\\_______\/\\\_____________\/\\\_ '
echo '        __\////////////__________\///________\///______________\///__'
echo '                                                                     '
echo '                                       Will now attempt installing...'
echo '                                                                     '

echo "Looking for a previous installation of GVM..."
if [ -d "$HOME/.gvm" ]; then
	echo "GVM found."
	echo ""
	echo "======================================================================================================"
	echo " You already have GVM installed."
	echo " GVM was found at:"
	echo ""
	echo "    $HOME/.gvm"
	echo ""
	echo " Please consider running the following if you need to upgrade."
	echo ""
	echo "    $ gvm selfupdate"
	echo ""
	echo "======================================================================================================"
	echo ""
	exit 0
fi

echo "Looking for JAVA_HOME..."
if [ -z "$JAVA_HOME" ]; then
	echo "Not found."
	echo ""
	echo "======================================================================================================"
	echo " Please ensure that you have a Java SDK installed and that JAVA_HOME environment variable is set."
	echo " accordingly."
	echo ""
	echo " Java can be found here:"
	echo "     http://www.oracle.com/technetwork/java/javase/downloads/index.html"
	echo ""
	echo " Set JAVA_HOME by editing your ~/.profile file and adding:"
	echo "     export JAVA_HOME=\"/path/to/my/jdk\""
	echo "======================================================================================================"
	echo ""
	exit 0
fi

echo "Validating JAVA_HOME..."
if [ ! -f "$JAVA_HOME/bin/java" ]; then
	echo "Invalid."
	echo ""
	echo "======================================================================================================"
	echo " Please ensure that your JAVA_HOME points to a valid Java SDK."
	echo " You are currently pointing to:"
	echo ""
	echo "  $JAVA_HOME"
	echo ""
	echo " This does not seem to be valid. Please rectify and restart."
	echo "======================================================================================================"
	echo ""
	exit 0	
fi

echo "Looking for zip..."
if [ -z $(which zip) ]; then
	echo "Not found."
	echo "======================================================================================================"
	echo " Please install zip on your system using your favourite package manager."
	echo ""
	echo " Restart after installing zip."
	echo "======================================================================================================"
	echo ""
	exit 0
fi

echo "Looking for unzip..."
if [ -z $(which unzip) ]; then
	echo "Not found."
	echo "======================================================================================================"
	echo " Please install unzip on your system using your favourite package manager."
	echo ""
	echo " Restart after installing unzip."
	echo "======================================================================================================"
	echo ""
	exit 0
fi

echo "Looking for curl..."
if [ -z $(which curl) ]; then
	echo "Not found."
	echo ""
	echo "======================================================================================================"
	echo " Please install curl on your system using your favourite package manager."
	echo ""
	echo " GVM uses curl for crucial interactions with it's backend server."
	echo ""
	echo " Restart after installing curl."
	echo "======================================================================================================"
	echo ""
	exit 0
fi

echo "Installing gvm scripts..."
mkdir -p "$HOME/.gvm/bin"
curl -s "$GVM_SERVICE/res/init?platform=$PLATFORM" > "$HOME/.gvm/bin/gvm-init.sh"
curl -s "$GVM_SERVICE/res/gvm" > "$HOME/.gvm/bin/gvm"
chmod +x "$HOME/.gvm/bin/gvm-init.sh"
chmod +x "$HOME/.gvm/bin/gvm"

echo "Creating candidate directories..."
mkdir -p "$HOME/.gvm/groovy"
mkdir -p "$HOME/.gvm/grails"
mkdir -p "$HOME/.gvm/griffon"
mkdir -p "$HOME/.gvm/gradle"

echo "Attempting to update bash profile..."


SNIPPET=$( cat << EOF
#THIS MUST BE AT THE END OF THE FILE FOR GVM TO WORK!!!
[[ -s "$HOME/.gvm/bin/gvm-init.sh" ]] && source "$HOME/.gvm/bin/gvm-init.sh"
EOF
)

BASH_PROFILE="$HOME/.bash_profile"
PROFILE="$HOME/.profile"
BASHRC="$HOME/.bashrc"
ZSHRC="$HOME/.zshrc"

if [ ! -f "$BASH_PROFILE" -a ! -f "$PROFILE" ]; then
	echo "#!/bin/bash" > "$BASH_PROFILE"
	echo "$SNIPPET" >> "$BASH_PROFILE"
	echo "Created and initialised $BASH_PROFILE"
else
	if [ -f "$BASH_PROFILE" ]; then
		if [[ -z `grep 'gvm-init.sh' "$BASH_PROFILE"` ]]; then
			echo -e "\n$SNIPPET" >> "$BASH_PROFILE"
			echo "Updated existing $BASH_PROFILE"
		fi
	fi

	if [ -f "$PROFILE" ]; then
		if [[ -z `grep 'gvm-init.sh' "$PROFILE"` ]]; then
			echo -e "\n$SNIPPET" >> "$PROFILE"
			echo "Updated existing $PROFILE"
		fi
	fi
fi

if [ ! -f "$BASHRC" ]; then
	echo "#!/bin/bash" > "$BASHRC"
	echo "$SNIPPET" >> "$BASHRC"
	echo "Created and initialised $BASHRC"
else
	if [[ -z `grep 'gvm-init.sh' "$BASHRC"` ]]; then
		echo -e "\n$SNIPPET" >> "$BASHRC"
		echo "Updated existing $BASHRC"
	fi
fi

if [ ! -f "$ZSHRC" ]; then
	echo "$SNIPPET" >> "$ZSHRC"
	echo "Created and initialised $ZSHRC"
else
	if [[ -z `grep 'gvm-init.sh' "$ZSHRC"` ]]; then
		echo -e "\n$SNIPPET" >> "$ZSHRC"
		echo "Updated existing $ZSHRC"
	fi
fi

echo "All done!"

echo ""
echo ""
echo "Please open a new terminal, or run the following in the existing one:"
echo ""
echo "    source \"$HOME/.gvm/bin/gvm-init.sh\""
echo ""
echo "Then issue the following command:"
echo ""
echo "    gvm help"
echo ""
echo "Enjoy!!!"