#!/usr/bin/env bash
set -Eeuo pipefail

REPO="${NG_REPO:-a2899882/NexusGate}"
BRANCH="${NG_BRANCH:-main}"

die() { printf '错误：%s\n' "$*" >&2; exit 1; }
info() { printf '\033[1;36m[NexusGate]\033[0m %s\n' "$*"; }
need_root() { [[ "${EUID}" -eq 0 ]] || die "请使用 root 运行"; }

IS_OPENWRT=false
[[ -f /etc/openwrt_release ]] && IS_OPENWRT=true
if $IS_OPENWRT; then DATA_DIR=/etc/nexusgate/data; else DATA_DIR=/var/lib/nexusgate; fi

panel_stop()    { if $IS_OPENWRT; then /etc/init.d/nexusgate stop; else systemctl stop nexusgate; fi }
panel_start()   { if $IS_OPENWRT; then /etc/init.d/nexusgate start; else systemctl start nexusgate; fi }
panel_restart() { if $IS_OPENWRT; then /etc/init.d/nexusgate restart; else systemctl restart nexusgate; fi }
panel_status()  { if $IS_OPENWRT; then /etc/init.d/nexusgate status; else systemctl status nexusgate --no-pager; fi }
panel_logs()    { local n="${1:-120}"; if $IS_OPENWRT; then logread 2>/dev/null | grep -a nexusgate | tail -n "$n"; else journalctl -u nexusgate -n "$n" --no-pager; fi }
caddy_reload()  { if $IS_OPENWRT; then /etc/init.d/caddy reload; else systemctl reload caddy; fi }
own_data()      { if ! $IS_OPENWRT; then chown -R nexusgate:nexusgate "$DATA_DIR"; chmod 0700 "$DATA_DIR"; fi }

backup() {
  need_root
  local output="${1:-/root/nexusgate-backup-$(date +%Y%m%d-%H%M%S).tar.gz}"
  local stage
  stage="$(mktemp -d /tmp/nexusgate-backup.XXXXXX)"
  trap 'rm -rf -- "$stage"' RETURN
  cp -a "$DATA_DIR" "$stage/data"
  cp -a /etc/nexusgate.env "$stage/nexusgate.env"
  [[ -f /etc/caddy/Caddyfile.d/nexusgate.caddy ]] && cp -a /etc/caddy/Caddyfile.d/nexusgate.caddy "$stage/nexusgate.caddy"
  tar -czf "$output" -C "$stage" .
  chmod 0600 "$output"
  info "备份已生成：$output"
}

restore() {
  need_root
  local archive="${1:-}"
  if [[ -z "$archive" ]]; then archive="$(find /root -maxdepth 1 -type f -name 'nexusgate-backup-*.tar.gz' -printf '%T@ %p\n' | sort -nr | head -n1 | cut -d' ' -f2-)"; fi
  [[ -f "$archive" ]] || die "未找到备份文件"
  if tar -tzf "$archive" | grep -Eq '(^/|(^|/)\.\.(/|$))'; then die "备份包包含不安全路径"; fi
  local stage safety
  stage="$(mktemp -d /tmp/nexusgate-restore.XXXXXX)"
  trap 'rm -rf -- "$stage"' RETURN
  tar -xzf "$archive" -C "$stage"
  [[ -f "$stage/data/nexusgate.json" && -f "$stage/nexusgate.env" ]] || die "备份包不完整"
  safety="/root/nexusgate-before-restore-$(date +%Y%m%d-%H%M%S).tar.gz"
  backup "$safety"
  panel_stop
  find "$DATA_DIR" -mindepth 1 -maxdepth 1 -exec rm -rf -- {} +
  cp -a "$stage/data/." "$DATA_DIR/"
  own_data
  cp -a "$stage/nexusgate.env" /etc/nexusgate.env && chmod 0600 /etc/nexusgate.env
  if [[ -f "$stage/nexusgate.caddy" ]]; then cp -a "$stage/nexusgate.caddy" /etc/caddy/Caddyfile.d/nexusgate.caddy; fi
  panel_start
  caddy_reload || true
  info "恢复完成；恢复前快照：$safety"
}

update_panel() {
  need_root
  local stage current_backup old_backup
  local -a old_backups=()
  current_backup="/root/nexusgate-before-update-$(date +%Y%m%d-%H%M%S).tar.gz"
  backup "$current_backup"
  stage="$(mktemp -d /tmp/nexusgate-update.XXXXXX)"
  trap 'rm -rf -- "$stage"' RETURN
  curl -fL --retry 3 "https://github.com/${REPO}/archive/refs/heads/${BRANCH}.tar.gz" -o "$stage/source.tgz"
  mkdir -p "$stage/source" && tar -xzf "$stage/source.tgz" -C "$stage/source" --strip-components=1
  [[ -f "$stage/source/server.js" ]] || die "更新包不完整"
  panel_stop
  cp -a "$stage/source/." /opt/nexusgate/
  if $IS_OPENWRT; then
    install -m 0755 /opt/nexusgate/openrc/nexusgate /etc/init.d/nexusgate
  else
    install -m 0644 /opt/nexusgate/systemd/nexusgate.service /etc/systemd/system/nexusgate.service
    systemctl daemon-reload
  fi
  install -m 0755 /opt/nexusgate/scripts/nexusgate.sh /usr/local/sbin/nexusgate
  own_data
  [[ ! -f "$DATA_DIR/nexusgate.json" ]] || chmod 0600 "$DATA_DIR/nexusgate.json"
  panel_start
  local healthy=false
  for _ in {1..30}; do
    if curl -fsS http://127.0.0.1:8787/healthz >/dev/null 2>&1; then healthy=true; break; fi
    sleep 1
  done
  if [[ "$healthy" != true ]]; then
    panel_logs 35 || true
    die "更新后控制面启动失败；可使用上方备份恢复"
  fi
  if [[ -f /etc/nexusgate/agent.env ]]; then
    info '检测到本机同时承载节点，更新本机 Agent'
    bash "$stage/source/scripts/agent-update.sh" || info 'Agent 更新失败；控制面仍可运行，请执行 ng-agent doctor 查看原因'
  fi
  # Only automatic pre-update snapshots are pruned; manual and pre-restore
  # backups remain untouched. Keep five successful rollback points on disk.
  mapfile -t old_backups < <(find /root -maxdepth 1 -type f -name 'nexusgate-before-update-*.tar.gz' -printf '%T@ %p\n' | sort -nr | sed -n '6,$p' | cut -d' ' -f2-)
  for old_backup in "${old_backups[@]}"; do rm -f -- "$old_backup"; done
  info "更新完成；更新前备份：$current_backup"
}

change_domain() {
  need_root
  local domain="${1:-}"
  if [[ -z "$domain" && -r /dev/tty ]]; then read -r -p '新域名：' domain </dev/tty; fi
  [[ "$domain" =~ ^[A-Za-z0-9.-]+$ ]] || die "域名格式不正确"
  sed -i -E "1s/^[^ ]+/${domain}/" /etc/caddy/Caddyfile.d/nexusgate.caddy
  caddy fmt --overwrite /etc/caddy/Caddyfile.d/nexusgate.caddy
  caddy validate --config /etc/caddy/Caddyfile && caddy_reload
  info "域名已更新为 https://${domain}"
}

certificate_status() {
  need_root
  caddy validate --config /etc/caddy/Caddyfile
  caddy_reload
  info "Caddy 已校验并重新加载；证书会在到期前自动续签"
  if $IS_OPENWRT; then logread 2>/dev/null | grep -a caddy | tail -n 30; else journalctl -u caddy -n 30 --no-pager; fi
}

change_account() {
  need_root
  local current="${1:-}" next='' first='' second=''
  if [[ -r /dev/tty ]]; then
    read -r -p '新管理员账号（留空则保持原账号）：' next </dev/tty
    read -r -s -p '新密码（至少 10 位，留空则保持原密码）：' first </dev/tty; printf '\n'
    if [[ -n "$first" ]]; then read -r -s -p '再次输入新密码：' second </dev/tty; printf '\n'; fi
  else
    die "修改管理员账号需要交互终端"
  fi
  [[ "$first" == "$second" ]] || die "两次输入不一致"
  [[ -n "$next" || -n "$first" ]] || die "账号与密码都没有更改"
  [[ -z "$first" || ${#first} -ge 10 ]] || die "密码至少需要 10 个字符"
  panel_stop
  set +e
  NG_DATA_FILE="$DATA_DIR/nexusgate.json" NG_NEW_USERNAME="$next" NG_NEW_PASSWORD="$first" node /opt/nexusgate/scripts/reset-password.js "$current"
  local result=$?
  unset first second
  set -e
  if [[ $result -eq 0 ]]; then
    if ! $IS_OPENWRT; then chown nexusgate:nexusgate "$DATA_DIR/nexusgate.json"; fi
    chmod 0600 "$DATA_DIR/nexusgate.json"
    sed -i '/^NG_ADMIN_PASSWORD=/d' /etc/nexusgate.env
  fi
  panel_start
  [[ $result -eq 0 ]] || die "管理员账号更新失败"
  info "管理员账号已更新，现有登录会话将在服务重启后失效"
}

uninstall_panel() {
  need_root
  local confirm archive
  if [[ -r /dev/tty ]]; then read -r -p '输入 UNINSTALL 确认卸载（会先自动备份）：' confirm </dev/tty; fi
  [[ "$confirm" == "UNINSTALL" ]] || die "已取消卸载"
  archive="/root/nexusgate-before-uninstall-$(date +%Y%m%d-%H%M%S).tar.gz"
  backup "$archive"
  if $IS_OPENWRT; then
    /etc/init.d/nexusgate stop >/dev/null 2>&1 || true
    /etc/init.d/nexusgate disable >/dev/null 2>&1 || true
    rm -f -- /etc/init.d/nexusgate
  else
    systemctl disable --now nexusgate.service >/dev/null 2>&1 || true
    rm -f -- /etc/systemd/system/nexusgate.service
    systemctl daemon-reload
    userdel nexusgate >/dev/null 2>&1 || true
    groupdel nexusgate >/dev/null 2>&1 || true
  fi
  rm -f -- /etc/nexusgate.env /etc/caddy/Caddyfile.d/nexusgate.caddy /usr/local/sbin/ng /usr/local/sbin/nexusgate
  rm -rf -- /opt/nexusgate "$DATA_DIR"
  caddy_reload >/dev/null 2>&1 || true
  printf '\nNexusGate 已卸载。可恢复备份：%s\n' "$archive"
}

menu() {
  printf '\nNexusGate 管理菜单\n'
  printf '1. 一键升级\n2. 更换域名\n3. 检查证书\n4. 生成迁移备份\n5. 恢复迁移备份\n6. 修改管理员账号 / 密码\n7. 查看状态\n8. 重启服务\n9. 查看日志\n10. 卸载面板\n0. 退出\n'
  local choice
  read -r -p '请选择：' choice </dev/tty
  case "$choice" in
    1) update_panel ;;
    2) change_domain ;;
    3) certificate_status ;;
    4) backup ;;
    5) restore ;;
    6) change_account ;;
    7) panel_status ;;
    8) need_root; panel_restart; caddy_reload; info '已重启' ;;
    9) panel_logs 120 ;;
    10) uninstall_panel ;;
    0) exit 0 ;;
    *) die '无效选择' ;;
  esac
}

case "${1:-menu}" in
  status) panel_status ;;
  restart) need_root; panel_restart; caddy_reload ;;
  logs) panel_logs "${2:-120}" ;;
  backup) backup "${2:-}" ;;
  restore) restore "${2:-}" ;;
  update) update_panel ;;
  domain) change_domain "${2:-}" ;;
  cert) certificate_status ;;
  account|password) change_account "${2:-}" ;;
  uninstall) uninstall_panel ;;
  menu|"") menu ;;
  *) die "用法：nexusgate {status|restart|logs|backup|restore|update|domain|cert|account|uninstall|menu}" ;;
esac