#!/usr/bin/env bash

installDocker() {
	local continue
	local distribution
	local codename

	echo "Installing prerequisites for Docker"
	sudo apt update && sudo apt install -y apt-transport-https ca-certificates curl software-properties-common

	echo "Fetching GPG key"
	curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

	echo "Verify the fingerprint is correct:"
	sudo apt-key fingerprint 0EBFCD88

	echo "Does the fingerprint match [9DC8 5822 9FC7 DD38 854A  E2D8 8D81 803C 0EBF CD88] ? [y]/n"
	read continue

	[[ "${continue}" != "" ]] && [[ "${continue}" = "y" ]] && [[ "${continue}" = "Y" ]] && return 137

	distribution=$(lsb_release -is | tr '[:upper:]' '[:lower:]')
	codename=$(lsb_release -cs)
   	sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/${distribution} ${codename} stable"

   	sudo apt update && sudo apt install -y docker-ce

   	[[ $? -ne 0 ]] && return 137

   	echo "Do you want to run docker commands without sudo? This will make your system less secure, effectively granting your user root privileges through the use of docker"
   	echo "y/[n]"
	read continue

	[[ "${continue}" != "" ]] && [[ "${continue}" = "y" ]] && [[ "${continue}" = "Y" ]] && return 0

	sudo usermod -aG docker ${USER}

	return 0
}

installGo() {
	echo "Installing golang"
	echo "Fetching latest tags from github..."
	local tags=$(curl -s https://github.com/golang/go/tags | awk '/golang\/go\/releases\/tag/{print $7}' FS='["/]')

	local latest=""

	if [[ ${tags} = "" ]]; then
		echo "Could not fetch the tags"
		return 2
	fi

	echo "Fetched the latest tags, deciding which one to use..."

	for tag in ${tags}[@]; do
		tag=${tag//go}
		if [[ ${tag} = *"rc"* ]]; then
		  continue
		elif [[ ${tag} = *"beta"* ]]; then
		  continue
		elif [[ ${tag} = *"alpha"* ]]; then
		  continue
		fi

		echo "Found the latest tag: ${tag}"
		latest=${tag}

		break
	done

	if [[ "${latest}" = "" ]]; then
		__err "Could not fetch the latest release"
		return 2
	fi

	echo "Downloading golang ${latest}"
	sudo curl -L --output "go.tar.gz" "https://storage.googleapis.com/golang/go${latest}.linux-amd64.tar.gz"

	echo "Installing golang in /usr/local/go"
	sudo tar -C /usr/local -xzf "go.tar.gz"

	[[ ! -e /usr/local/go/bin ]] && echo "Did not install go properly" && return 137

	grep -q /usr/local/go/bin ~/.bashrc

	if [[ $? -ne 0 ]]; then
		echo "Adding PATH export to .bashrc to include golang binary location"
		echo "export PATH=\$PATH:/usr/local/go/bin" | tee -a ~/.bashrc
	fi

	echo "Removing the downloaded file"
	sudo rm -f "go.tar.gz"

	return 0
}

installRelay() {
	echo "Installing npiperelay"
	echo "Fetching the relay from github"
	/usr/local/go/bin/go get -d github.com/jstarks/npiperelay
	[[ $? -ne 0 ]] && echo "Could not fetch the relay" && return 137

	echo "Building the relay binary for windows"
	export GOOS=windows
	/usr/local/go/bin/go build -o /mnt/c/Users/${USER}/go/bin/npiperelay.exe github.com/jstarks/npiperelay
	[[ $? -ne 0 ]] && echo "Could not build the binary" && return 137

	echo "Linking the relay binary"
	sudo ln -s /mnt/c/Users/${USER}/go/bin/npiperelay.exe /usr/local/bin/npiperelay.exe
	[[ $? -ne 0 ]] && echo "Could not link the binary" && return 137

	echo "Installing socat"
	sudo apt update
	sudo apt install -y socat
	[[ $? -ne 0 ]] && echo "Could not install the requirements" && return 137

	return 0
}

addStartupScript() {
	echo "Creating the docker relay startup script"
	local relayLocation=~/.docker-relay

	touch "${relayLocation}"
	chmod +x "${relayLocation}"

	cat << "EOF" | tee -a "${relayLocation}" > /dev/null
#!/usr/bin/env bash

isRelayRunning() {
	[[ $(ps aux | grep -v grep | grep "socat UNIX-LISTEN:/var/run/docker.sock,fork,group=docker,umask=007 EXEC" | wc -l) -eq 0 ]] && return 0

	return 1
}

isRelayRunning
RUNNING=$?

if [[ ${RUNNING} -eq 0 ]]; then
	echo "Starting docker relay"
	sudo ls > /dev/null
	exec sudo socat UNIX-LISTEN:/var/run/docker.sock,fork,group=docker,umask=007 EXEC:"npiperelay.exe -ep -s //./pipe/docker_engine",nofork &
fi

RETRIES=20
until [[ ${RUNNING} -eq 1 ]] || [[ ${RETRIES} -eq 0 ]]; do
	isRelayRunning
	RUNNING=$?
	sleep 1
	RETRIES=$((RETRIES-1))
done

if [[ ${RUNNING} -ne 1 ]] && [[ ${RETRIES} -eq 0 ]]; then
	echo "Could not initialize the docker relay!"
	echo "Exiting..."
	exit 137
fi

exit 0
EOF

	echo "Aliasing docker to run the relay script first in ~/.bash_aliases"

	cat << EOF | tee -a ~/.bash_aliases > /dev/null
alias docker="${relayLocation} && docker"
EOF

	echo "Done, try running 'docker ps'"
	return 0
}

installDockerCompose() {
	echo "Installing docker-compose"
	echo "Fetching latest tags from github..."
	local tags=$(curl -s https://github.com/docker/compose/tags | awk '/docker\/compose\/releases\/tag/{print $7}' FS='["/]')

	local latest=""

	if [[ ${tags} = "" ]]; then
		echo "Could not fetch the tags"
		return 2
	fi

	echo "Fetched the latest tags, deciding which one to use..."

	for tag in ${tags}[@]; do
		tag=${tag//go}
		if [[ ${tag} = *"rc"* ]]; then
		  continue
		elif [[ ${tag} = *"beta"* ]]; then
		  continue
		elif [[ ${tag} = *"alpha"* ]]; then
		  continue
		fi

		echo "Found the latest tag: ${tag}"
		latest=${tag}

		break
	done

	if [[ "${latest}" = "" ]]; then
		__err "Could not fetch the latest release"
		return 2
	fi

	local compose_path=$(which docker-compose)

	which docker-compose > /dev/null 2>&1
	if [[ $? -ne 0 ]]; then
		compose_path=/usr/local/bin/docker-compose
		__warn "You do not seem to have docker compose installed, installing to ${compose_path}"
	fi

	__msg "Installing docker-compose ${latest}"
	sudo curl -L https://github.com/docker/compose/releases/download/${latest}/docker-compose-`uname -s`-`uname -m` --output "${compose_path}" &&
	sudo chmod +x "${compose_path}"

	[[ $? -ne 0 ]] && echo "Docker compose might be running, please close all processes before installing this version" && return 2

	return 0
}

initialize() {
	installDocker
	[[ $? -ne 0 ]] && echo "Could not install Docker" && return 137

	installGo
	[[ $? -ne 0 ]] && echo "Could not install Go" && return 137

	installRelay
	[[ $? -ne 0 ]] && echo "Could not install relay" && return 137

	addStartupScript
	[[ $? -ne 0 ]] && echo "Could not add the startup script" && return 137

	installDockerCompose
	[[ $? -ne 0 ]] && echo "Could not install docker compose" && return 137

	return 0
}


[[ ${1} = "" ]] && initialize || "$@"

exit $?