#!/bin/bash

SDS_VERSION="0.0.1"

DEFAULT_VERSION="latest"
DEFAULT_PLATFORM="linux"
DEFAULT_ARCH="amd64"

SYNC_VERSION=$DEFAULT_VERSION
SYNC_PLATFORM=$DEFAULT_PLATFORM
SYNC_ARCH=$DEFAULT_ARCH

PKG_NAME="syncthing-$SYNC_PLATFORM-$SYNC_ARCH-v$SYNC_VERSION"

SDS_DIR_TMP="$HOME/.cache/steamdecksync"
SDS_DIR_BIN="$HOME/.local/bin"
SDS_DIR_SYS="$HOME/.config/systemd/user"


sds_extract_local_files () {
	tar -xf $SDS_DIR_TMP/syncthing-files.tar.gz -C $SDS_DIR_TMP
}

sds_fetch_remote_files () {
	echo "Pulling Syncthing package $PKG_NAME"

	local REPO_URL="https://github.com/syncthing/syncthing/"
	local RELEASE_URL="$REPO_URL/releases/download/v$SYNC_VERSION/$PKG_NAME.tar.gz"

	curl --silent -L $RELEASE_URL > $SDS_DIR_TMP/syncthing-files.tar.gz
}

sds_install () {
	cp $SDS_DIR_TMP/$PKB_NAME/syncthing $SDS_DIR_BIN/syncthing

	systemctl --user daemon-reload
	systemctl --user enable syncthing.service
	systemctl --user start syncthing.service
}

sds_make_syncthing_service () {
	cat > $HOME/.config/systemd/user/syncthing.service <<- EOM
[Unit]
Description=Syncthing - Open Source Continuous File Synchronization
Documentation=man:syncthing(1)
StartLimitIntervalSec=60
StartLimitBurst=4

[Service]
ExecStart=/home/deck/.local/bin/syncthing serve --no-browser --no-restart --logflags=0
Restart=on-failure
RestartSec=1
SuccessExitStatus=3 4
RestartForceExitStatus=3 4

# Hardening
SystemCallArchitectures=native
MemoryDenyWriteExecute=true
NoNewPrivileges=true

[Install]
WantedBy=default.target
EOM
}

sds_set_package_name () {
	if [ $SYNC_VERSION == "latest" ]; then
	local TAG_URL="https://api.github.com/repos/syncthing/syncthing/tags?per_page=1"
	local SYNC_VERSION=$(\
		curl --silent $TAG_URL | \
		grep '"name":' | \
		sed -r 's/.*v(.*)\".*/\1/'
	)
	fi

	PKG_NAME="syncthing-$SYNC_PLATFORM-$SYNC_ARCH-v$SYNC_VERSION"
}

sds_setup () {
	mkdir -p $SDS_DIR_TMP
	mkdir -p $SDS_DIR_BIN
	mkdir -p $SDS_DIR_SYS
}

sds_uninstall () {
	echo "Stopping/Disabling Systemd User Service"
	systemctl --user disable syncthing.service
	systemctl --user stop syncthing.service

	echo "Removing SDS directories and files"
	rm -rf $SDS_DIR_TMP
	rm $SDS_DIR_BIN/syntching
	rm $SDS_DIR_SYS/syncthing.service

	echo "SDS uninstalled"
}

sds_usage () {
	echo -e "Usage: syncthing-deck-setup [<options>]"
	
	printf "\n%17s   %s" "-V, --version"        "Specify a Syncthing Version. Default is latest."
	printf "\n%17s   %s" "-P, --platform"       "Specify an OS/Platform. Default is linux."
	printf "\n%17s   %s" "-A, --arch"           "Specify an architecture. Default is amd64."
	printf "\n%17s   %s" "-U, --uninstall"      "Remove files setup with this script."
	printf "\n%17s   %s" "-v"							      "Show version"
	printf "\n%17s   %s" "-h"							      "Show this usage"
	echo -e "\n"
}


while [[ $# -gt 0 ]]; do
	case $1 in
		-V|--version)
			SYNC_VERSION="$2"
			shift
			shift
			;;
		-P|--platform)
			SYNC_PLATFORM="$2"
			shift
			shift
			;;
		-A|--arch)
			SYNC_ARCH="$2"
			shift
			shift
			;;
		-U|--uninstall)
			sds_uninstall
			exit 0
			;;
		-v)
			echo "Syncthing Deck Setup version $SDS_VERSION"
			exit 0
			;;
		*)
			sds_usage
			exit 0
			;;
	esac
done


sds_setup
sds_set_package_name
sds_fetch_remote_files
sds_make_syncthing_service
sds_extract_local_files
sds_install