#!/bin/bash
set -e

GREEN='\033[0;32m'
YELLOW='\033[1;33m'
RED='\033[0;31m'
NC='\033[0m'

REPO="fosrl/newt"
INSTALL_DIR="/opt/newt"
SERVICE_NAME="PVE-MGNT"
SYMLINK="${INSTALL_DIR}/newt_latest"
SERVICE_FILE="/etc/systemd/system/${SERVICE_NAME}.service"

info()  { echo -e "${GREEN}[INFO]${NC} $1"; }
warn()  { echo -e "${YELLOW}[WARN]${NC} $1"; }
error() { echo -e "${RED}[ERROR]${NC} $1"; }

MODE="auto"

for arg in "$@"; do
  case "$arg" in
    --install) MODE="install" ;;
    --update) MODE="update" ;;
    --reinstall|--force) MODE="reinstall" ;;
    *) error "Unbekannter Parameter: $arg" && exit 1 ;;
  esac
done

get_latest_version() {
  curl -fsSL "https://api.github.com/repos/${REPO}/releases/latest" | grep -Po '"tag_name": *"\K[^"]+'
}

download_newt() {
  version="$1"
  arch=$(uname -m)

  case "$arch" in
    x86_64) file="newt_linux_amd64" ;;
    aarch64) file="newt_linux_arm64" ;;
    armv7l) file="newt_linux_arm32" ;;
    *) error "Nicht unterstützte Architektur: $arch" && exit 1 ;;
  esac

  url="https://github.com/${REPO}/releases/download/${version}/${file}"
  target="${INSTALL_DIR}/newt_${version}"
  temp_target="${target}.tmp"

  mkdir -p "$INSTALL_DIR"
  info "⬇️ Lade $url herunter …"
  curl -fsSL "$url" -o "$temp_target" || { error "Download fehlgeschlagen."; rm -f "$temp_target"; exit 1; }

  chmod +x "$temp_target"
  mv "$temp_target" "$target"
  ln -sf "$target" "$SYMLINK"
  info "✅ newt ${version} installiert als ${target}"
}

cleanup_old_versions() {
  cd "$INSTALL_DIR"
  keep=$(readlink -f newt_latest)
  versions=($(ls -1 newt_* | grep -v latest | sort -Vr))
  count=0
  for ver in "${versions[@]}"; do
    if [[ "$(readlink -f "$ver")" != "$keep" ]]; then
      ((count++))
      if [ "$count" -gt 1 ]; then
        info "🧹 Entferne alte Version: $ver"
        rm -f "$ver"
      fi
    fi
  done
}

setup_systemd_service() {
  info "🛠️ Erstelle systemd-Dienst ${SERVICE_NAME} ..."

  # Eingabeaufforderungen im User-Kontext
  read -rp "🆔 Bitte gib die Pangolin-ID ein: " PANGOLIN_ID
  read -rp "🔑 Bitte gib das Secret ein: " PANGOLIN_SECRET
  read -rp "🌐 Bitte gib den Endpoint (z. B. https://pangolin.domain.de) ein: " PANGOLIN_ENDPOINT

  SERVICE_CONTENT="[Unit]
Description=Newt Client - ${SERVICE_NAME}
After=network.target

[Service]
ExecStart=${SYMLINK} --id ${PANGOLIN_ID} --secret ${PANGOLIN_SECRET} --endpoint ${PANGOLIN_ENDPOINT}
Restart=always
RestartSec=5

[Install]
WantedBy=multi-user.target"

  echo "$SERVICE_CONTENT" | sudo tee "$SERVICE_FILE" > /dev/null

  sudo systemctl daemon-reexec
  sudo systemctl daemon-reload
  sudo systemctl enable "$SERVICE_NAME"
  sudo systemctl start "$SERVICE_NAME"
  info "✅ systemd-Dienst ${SERVICE_NAME} wurde eingerichtet und gestartet."
}

perform_install() {
  if [ -f "$SERVICE_FILE" ]; then
    warn "Dienst ${SERVICE_NAME} existiert bereits. Nutze --reinstall für Neuinstallation."
    exit 0
  fi
  version=$(get_latest_version)
  version=${version#v}
  info "📦 Neueste Version: ${version}"
  download_newt "$version"
  cleanup_old_versions
  setup_systemd_service
  info "🚀 Installation abgeschlossen!"
}

perform_update() {
  if [ ! -f "$SERVICE_FILE" ]; then
    error "Dienst ${SERVICE_NAME} nicht installiert. Nutze --install oder --reinstall."
    exit 1
  fi
  version=$(get_latest_version)
  version=${version#v}
  info "📦 Neueste Version: ${version}"

  if [ -f "${INSTALL_DIR}/newt_${version}" ]; then
    info "✅ Version ${version} ist bereits installiert. Kein Update nötig."
  else
    download_newt "$version"
    cleanup_old_versions
    sudo systemctl restart "$SERVICE_NAME"
    info "🔄 Dienst ${SERVICE_NAME} wurde neu gestartet."
  fi
  info "🚀 Update abgeschlossen!"
}

perform_reinstall() {
  version=$(get_latest_version)
  version=${version#v}
  info "📦 Neueste Version: ${version}"
  download_newt "$version"
  cleanup_old_versions
  sudo rm -f "$SERVICE_FILE" || true
  setup_systemd_service
  info "🚀 Reinstallation abgeschlossen!"
}

main() {
  case "$MODE" in
    install) perform_install ;;
    update) perform_update ;;
    reinstall) perform_reinstall ;;
    auto)
      if [ -f "$SERVICE_FILE" ]; then
        MODE="update"
      else
        MODE="install"
      fi
      main  # rekursiver Aufruf mit gesetztem MODE
      ;;
  esac
}

main "$@"