#!/bin/bash
set -euxo pipefail;

# Constants
readonly ARCHITECTURE={{ binary_architecture | quote }};
readonly BINARIES=( "cleanup" "genkey" "server" );
readonly BIN_DIR={{ installation_directory | quote }};
readonly PREFIX="linx";
readonly SYSTEM_USER={{ system_user | quote }};

# Helper building filenames
function getFile() {
  echo "$PREFIX-$2-$1_$ARCHITECTURE";
}

# Helper modifing owners and permissions
function correctPermissions() {
  chown --no-dereference "root:$SYSTEM_USER" "$1";
  chmod u=rwx,g=rx,o= "$1";
}

# Check newest version installed
installed="$(
  (ls "$BIN_DIR" |
  grep --only-matching --perl-regexp '(?<=-)v\d+(\.\d+)*(?=_)' |
  sort --version-sort --reverse --unique |
  head --lines=1) ||
  true
)";

# Check version from upstream
version="$(
  curl --silent https://github.com/andreimarcu/linx-server/releases.atom |
  grep --only-matching --perl-regexp '(?<=/releases/tag/)v\d+(\.\d+)*(?=")' |
  head --lines=1
)";

# Check for missing version numbers
if [[ -z "$installed" ]]; then
	installed="v0";
fi
if [[ -z "$version" ]]; then
	error "Missing version available";
	exit 2;
fi

# Check if version is already installed
if [[ "$installed" = "$version" ]]; then
	exit 0;
fi

# Remove version and redownloading (only applies on fallback)
for binary in "${BINARIES[@]}"; do
  fileName="$(getFile "$version" "$binary")";
  filePath="$BIN_DIR/$fileName";
  url="https://github.com/andreimarcu/linx-server/releases/download/$version/$fileName";
  rm --force "$filePath";
  wget --quiet --output-document="$filePath" "$url";
  correctPermissions "$filePath";
done

# Relink new binaries
for binary in "${BINARIES[@]}"; do
  toLinkPath="$BIN_DIR/$(getFile "$version" "$binary")";
  linkPath="$BIN_DIR/$PREFIX-$binary";
  ln --force --symbolic "$toLinkPath" "$linkPath";
  correctPermissions "$linkPath";
done

# Remove old version
for binary in "${BINARIES[@]}"; do
  fileName="$(getFile "$installed" "$binary")";
  rm --force "$BIN_DIR/$fileName";
done

# Restart service
if systemctl is-enabled {{ service_name | quote }}; then
  systemctl restart {{ service_name | quote }};
fi