#!/usr/bin/env bash

function run_installer()
{
	####### Init vars

	HOMEBREW_PREFIX=/usr/local
	HOMEBREW_CACHE=/Library/Caches/Homebrew
	HOMEBREW_REPO=https://github.com/Homebrew/homebrew
	OSX_REQUIERED_VERSION="10.7.0"


	declare OS_TYPE
	declare OSX_VERSION
	declare GIT_PATH
	declare RUBY_PATH
	declare BREW_PATH
	declare INSTALL_FILES=""

	errorMessages=""
	isOsVersion=false
	isGit=false
	isRuby=false
	isBrew=false
	canContinue=true
	depCount=0
	depFound=0



	####### Setup colors

	red=`tput setaf 1`
	green=`tput setaf 2`
	yellow=`tput setaf 3`
	blue=`tput setaf 4`
	magenta=`tput setaf 5`
	cyan=`tput setaf 6`
	white=`tput setaf 7`
	b=`tput bold`
	u=`tput sgr 0 1`
	ul=`tput smul`
	xl=`tput rmul`
	stou=`tput smso`
	xtou=`tput rmso`
	dim=`tput dim`
	reverse=`tput rev`
	reset=`tput sgr0`


	function head() {
		echo "${blue}${b}==>${white} $1${reset}"
	}

	function info() {
		echo "${blue}${b}==>${reset} $1"
	}

	function successHeading() {
		echo "${green}${b}==> $1${reset}"
	}

	function success() {
		echo "${green}${b}==>${reset}${green} $1${reset}"
	}

	function error() {
		echo "${red}==> ${u}${b}${red}$1${reset}"
	}

	function smallError() {
		echo "${red}==>${reset} $1"
	}

	function green() {
		echo "${green}$1${reset}"
	}

	function red() {
		echo "${red}$1${reset}"
	}

	function check() {
		echo "${green}${bold} ✓${reset}  $1${reset}"
	}

	function uncheck() {
		echo "${red}${bold} ✘${reset}  $1${reset}"
	}



	####### Setup methods

	function wait_for_user() {
		while :
		do
			read -p "${blue}==>${reset} $1 (y/N) " imp
			case $imp in
				[yY] ) echo; break ;;
				* ) abortInstall "${red}==>${reset} Process stopped by user. To resume the install run the one-liner command again." ;;
			esac
		done
	}

	function exe() {
		echo "\$ $@"; "$@"
	}

	function detectGeth() {
		find_geth
		echo ""

		if [[ $isGeth == true ]]
		then
			wait_for_user "Do you want to update geth?"
		fi
	}

	function detectOS() {
		if [[ "$OSTYPE" == "linux-gnu" ]]
		then
			OS_TYPE="linux"
			get_linux_dependencies
		elif [[ "$OSTYPE" == "darwin"* ]]
		then
			OS_TYPE="osx"
			get_osx_dependencies
		else
			OS_TYPE="win"
			abortInstall "${red}==>${reset} ${b}OS not supported:${reset} geth one-liner currently support OS X, Ubuntu and Debian.\nFor instructions on installing ethereum on other platforms please visit ${u}${blue}http://ethereum.org/${reset}"
		fi

		echo

		if [[ $depCount == $depFound ]]
		then
			green "Found all dependencies ($depFound/$depCount)"
		else
			if [[ $canContinue == true ]]
			then
				red "Some dependencies are missing ($depFound/$depCount)"
			elif [[ $canContinue == false && $depFound == 0 ]]
			then
				red "All dependencies are missing and cannot be auto-installed ($depFound/$depCount)"
				abortInstall "$errorMessages";
			elif [[ $canContinue == false ]]
			then
				red "Some dependencies which cannot be auto-installed are missing ($depFound/$depCount)"
				abortInstall "$errorMessages";
			fi
		fi
	}

	function get_osx_dependencies()
	{
		macos_version
		find_git
		find_ruby
		find_brew

		INSTALL_FILES+="${blue}${dim}==> Ethereum:${reset}\n"
		INSTALL_FILES+=" ${blue}${dim}➜${reset}  $GOPATH/src/github.com/ethereum/go-ethereum\n"
		INSTALL_FILES+=" ${blue}${dim}➜${reset}  $HOMEBREW_PREFIX/Cellar/ethereum\n"
		INSTALL_FILES+=" ${blue}${dim}➜${reset}  $HOMEBREW_CACHE/ethereum--git\n"
	}

	function macos_version()
	{
		declare -a reqVersion
		declare -a localVersion

		depCount=$((depCount+1))
		OSX_VERSION=`/usr/bin/sw_vers -productVersion 2>/dev/null`

		if [ -z "$OSX_VERSION" ]
		then
			uncheck "OS X version not supported 🔥"
			isOsVersion=false
			canContinue=false
		else
			IFS='.' read -a localVersion <<< "$OSX_VERSION"
			IFS='.' read -a reqVersion <<< "$OSX_REQUIERED_VERSION"

			if (( ${reqVersion[0]} <= ${localVersion[0]} )) && (( ${reqVersion[1]} <= ${localVersion[1]} ))
			then
				check "OS X Version ${OSX_VERSION}"
				isOsVersion=true
				depFound=$((depFound+1))
				return
			else
				uncheck "OS X version not supported"
				isOsVersion=false
				canContinue=false
			fi
		fi

		errorMessages+="${red}==>${reset} ${b}Mac OS version too old:${reset} geth requires OS X version ${red}$OSX_REQUIERED_VERSION${reset} at least in order to run.\n"
		errorMessages+="    Please update the OS and reload the install process.\n"
	}

	function find_geth()
	{
		GETH_PATH=`which geth 2>/dev/null`

		if [[ -f $GETH_PATH ]]
		then
			check "Found geth: $GETH_PATH"
			echo "$($GETH_PATH version)"
			isGeth=true
		else
			uncheck "Geth is missing"
			isGeth=false
		fi
	}

	function find_git()
	{
		depCount=$((depCount+1))

		GIT_PATH=`which git 2>/dev/null`

		if [[ -f $GIT_PATH ]]
		then
			check "$($GIT_PATH --version)"
			isGit=true
			depFound=$((depFound+1))
		else
			uncheck "Git is missing"
			isGit=false
		fi
	}

	function find_ruby()
	{
		depCount=$((depCount+1))

		RUBY_PATH=`which ruby 2>/dev/null`

		if [[ -f $RUBY_PATH ]]
		then
			RUBY_VERSION=`ruby -e "print RUBY_VERSION"`
			check "Ruby ${RUBY_VERSION}"
			isRuby=true
			depFound=$((depFound+1))
		else
			uncheck "Ruby is missing 🔥"
			isRuby=false
			canContinue=false
			errorMessages+="${red}==>${reset} ${b}Couldn't find Ruby:${reset} Brew requires Ruby which could not be found.\n"
			errorMessages+="    Please install Ruby using these instructions ${u}${blue}https://www.ruby-lang.org/en/documentation/installation/${reset}.\n"
		fi
	}

	function find_brew()
	{
		BREW_PATH=`which brew 2>/dev/null`

		if [[ -f $BREW_PATH ]]
		then
			check "$($BREW_PATH -v)"
			isBrew=true
			depFound=$((depFound+1))
		else
			uncheck "Homebrew is missing"
			isBrew=false

			INSTALL_FILES+="${blue}${dim}==> Homebrew:${reset}\n"
			INSTALL_FILES+=" ${blue}${dim}➜${reset}  $HOMEBREW_PREFIX/bin/brew\n"
			INSTALL_FILES+=" ${blue}${dim}➜${reset}  $HOMEBREW_PREFIX/Library\n"
			INSTALL_FILES+=" ${blue}${dim}➜${reset}  $HOMEBREW_PREFIX/share/man/man1/brew.1\n"
		fi

		depCount=$((depCount+1))
	}

	function install_brew()
	{
		if [[ $isBrew == false ]]
		then
			head "Installing Homebrew"

			if [[ $isRuby == true ]]
			then
				ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
			else
				cd /usr

				if [[ ! -d $HOMEBREW_PREFIX ]]
				then
					sudo mkdir $HOMEBREW_PREFIX
					sudo chmod g+rwx $HOMEBREW_PREFIX
				fi

				if [[ ! -d $HOMEBREW_CACHE ]]
				then
					sudo mkdir $HOMEBREW_CACHE
					sudo chmod g+rwx $HOMEBREW_CACHE
				fi

				DEVELOPER_DIR=`/usr/bin/xcode-select -print-path 2>/dev/null`

				if [[ ! $(ls -A $DEVELOPER_DIR) || ! -f $DEVELOPER_DIR/usr/bin/git ]]
				then
					info "Installing the Command Line Tools (expect a GUI popup):"
					sudo /usr/bin/xcode-select --install

					echo "Press any key when the installation has completed"
				fi

				cd $HOMEBREW_PREFIX

				bash -o pipefail -c "curl -fsSL ${HOMEBREW_REPO}/tarball/master | tar xz -m --strip 1"
			fi

			find_brew
			echo

			if [[ $isBrew == false ]]
			then
				abortInstall "Couldn't install brew"
			fi
		fi
	}

	function osx_installer()
	{
		osx_dependency_installer

		echo
		head "Installing ethereum"

		info "Adding ethereum repository"
		exe brew tap ethereum/ethereum
		echo

		info "Updating brew"
		exe brew update
		echo

		info "Installing geth"
		if [[ $isGeth == true ]]
		then
			exe brew reinstall ethereum
		else
			exe brew install ethereum
			exe brew linkapps ethereum
		fi
		echo
	}

	function osx_dependency_installer()
	{
		if [[ $isGit == false ]];
		then
			echo "Installing Git"
		fi


		if [[ $isRuby == false ]];
		then
			echo "Installing Ruby"
		fi

		if [[ $isBrew == false ]];
		then
			install_brew
		fi
	}


	function get_linux_dependencies()
	{
		find_apt

		INSTALL_FILES+="${blue}${dim}==> Ethereum:${reset}\n"
		INSTALL_FILES+=" ${blue}${dim}➜${reset}  /usr/bin/geth\n"
	}

	function find_apt()
	{
		APT_PATH=`which apt-get 2>/dev/null`

		if [[ -f $APT_PATH ]]
		then
			check "apt-get"
			echo "$($APT_PATH -v)"
			isApt=true
		else
			uncheck "apt-get is missing"
			isApt=false
			abortInstall "${red}==>${reset} ${b}OS not supported:${reset} geth one-liner currently support OS X, Ubuntu and Debian.\nFor instructions on installing ethereum on other platforms please visit ${u}${blue}http://ethereum.org/${reset}"
		fi
	}

	function linux_installer()
	{
		echo
		head "Installing ethereum"

		info "Installing common software properties"
		exe sudo apt-get install -q -y software-properties-common
		echo

		if [[ $isGeth == true ]]
		then
			info "Uninstalling previous geth version"
			exe sudo apt-get remove -y
			exe sudo apt-get clean
		fi

		info "Adding ethereum repository"
		exe sudo add-apt-repository -y ppa:ethereum/ethereum
		echo

		info "Updating packages"
		exe sudo apt-get update -q -y
		echo

		info "Installing geth"
		exe sudo apt-get install -q -y geth
		echo
	}

	function install()
	{
		if [[ $OS_TYPE == "osx" ]]
		then
			osx_installer
		elif [[ $OS_TYPE == "linux" ]]
		then
			linux_installer
		fi
	}

	function verify_installation()
	{
		info "Verifying installation"
		find_geth

		if [[ $isGeth == false ]]
		then
			abortInstall
		fi
	}

	function abortInstall()
	{
		echo
		error "Installation failed"
		echo -e "$1"
		echo
		exit 0
	}

	function finish()
	{
		echo
		successHeading "Installation successful!"
		head "Next steps"
		info "Run ${cyan}\`geth help\`${reset} to get started.${reset}"
		echo
		exit 0
	}

	####### Run the script
	tput clear
	echo
	echo
	echo " ${blue}∷ ${b}${green} WELCOME TO THE FRONTIER ${reset} ${blue}∷${reset}"
	echo
	echo

	# Check dependencies
	head "Looking for geth"
	detectGeth

	# Check dependencies
	head "Checking dependencies"
	detectOS

	echo
	head "This script will install:"
	echo "$INSTALL_FILES"
	echo

	# Display disclaimer
	error "Before installing Geth (ethereum CLI) read this:"
	echo
	echo " ${red}${dim}➜${reset}  ${b}${cyan}Frontier${reset} is a ${red}live testnet${reset}, it is not the 'main release' of Ethereum, but rather an ${red}initial beta prerelease;${reset}"
	echo " ${red}${dim}➜${reset}  You'd be ${b}mad${reset} to use this for anything approaching ${u}${red}${b}"important" or "valuable"${reset}. ${red}Expect dragons;${reset}"
	echo " ${red}${dim}➜${reset}  If you're in any doubt, stand back and enjoy the show. It's so ${red}unstable${reset}, even Chuck Norris would run away and hide from it;"
	echo " ${red}${dim}➜${reset}  We fully expect ${red}instability and consensus flaws${reset} in the client, some of which may be exploitable;"
	echo

	# Prompt user to continue or abort
	wait_for_user "${b}I understand,${reset} I want to install Geth (ethereum CLI)"

	# Install dependencies and geth
	install

	# Check installation
	verify_installation

	# Display goodby message
	finish
}

run_installer