#!/usr/bin/env sh
set -eu

SERVER=""
BIN_URL=""
VERSION=""
SHA256=""

while [ "$#" -gt 0 ]; do
  case "$1" in
    --server) SERVER="$2"; shift 2 ;;
    --bin-url) BIN_URL="$2"; shift 2 ;;
    --version) VERSION="$2"; shift 2 ;;
    --sha256) SHA256="$2"; shift 2 ;;
    *) echo "未知参数：$1" >&2; exit 1 ;;
  esac
done

if [ "$(id -u)" -ne 0 ]; then
  echo "请使用 root 用户运行" >&2
  exit 1
fi

if [ -z "$BIN_URL" ]; then
  if [ -z "$SERVER" ]; then
    if [ -f /etc/lightops/agent.toml ]; then
      SERVER="$(awk -F= '/server_url/ { gsub(/[ "]/, "", $2); print $2; exit }' /etc/lightops/agent.toml)"
    fi
  fi
  if [ -z "$SERVER" ]; then
    echo "缺少 --server 或 --bin-url" >&2
    exit 1
  fi
  OS="$(uname -s | tr '[:upper:]' '[:lower:]')"
  ARCH="$(uname -m)"
  SUFFIX=""
  if [ -n "$VERSION" ]; then
    SUFFIX="-$VERSION"
  fi
  BIN_URL="$SERVER/downloads/lightops-agent-$OS-$ARCH$SUFFIX"
fi

TMP_BIN="$(mktemp)"
echo "正在下载 Agent：$BIN_URL"
curl -fL --retry 3 --connect-timeout 10 "$BIN_URL" -o "$TMP_BIN"
if [ -n "$SHA256" ]; then
  echo "$SHA256  $TMP_BIN" | sha256sum -c -
fi
chmod +x "$TMP_BIN"
"$TMP_BIN" --version >/dev/null

systemctl stop lightops-agent 2>/dev/null || true
if [ -x /usr/local/bin/lightops-agent ]; then
  BACKUP="/usr/local/bin/lightops-agent.bak.$(date +%Y%m%d%H%M%S)"
  cp /usr/local/bin/lightops-agent "$BACKUP"
else
  BACKUP=""
fi
mv "$TMP_BIN" /usr/local/bin/lightops-agent

if ! systemctl start lightops-agent; then
  echo "新版本启动失败，正在回滚" >&2
  if [ -n "$BACKUP" ]; then
    cp "$BACKUP" /usr/local/bin/lightops-agent
    systemctl start lightops-agent || true
  fi
  exit 1
fi

sleep 2
if ! systemctl is-active --quiet lightops-agent; then
  echo "新版本未保持运行，正在回滚" >&2
  if [ -n "$BACKUP" ]; then
    cp "$BACKUP" /usr/local/bin/lightops-agent
    systemctl restart lightops-agent || true
  fi
  journalctl -u lightops-agent -n 80 --no-pager >&2 || true
  exit 1
fi

echo "LightOps Agent 已升级"