#!/bin/bash
# =============================================================================
# P600 机载电脑 - SSH 隧道自启服务安装脚本
# 用法: 传到 P600 上执行: bash setup_p600_tunnel.sh
# 功能: 开机自启 rosbridge 隧道，断线自动重连
# 隧道: P600:8080 → 云服务器 121.41.216.243:9090
# 网页连接地址: ws://121.41.216.243:9090
# =============================================================================

set -e

SERVICE_NAME="rosbridge-tunnel.service"
SERVICE_PATH="/etc/systemd/system/${SERVICE_NAME}"
SSH_HOST="root@121.41.216.243"
SSH_PORT="9090"
LOCAL_PORT="8080"

echo "========================================="
echo "  P600 SSH 隧道自启服务安装"
echo "========================================="
echo ""

# 检查是否以 root 运行
if [ "$EUID" -ne 0 ]; then
    echo "❌ 请使用 root 用户运行: sudo bash setup_p600_tunnel.sh"
    exit 1
fi

# 检查 SSH 连接是否可用
echo "🔍 测试 SSH 连接到 ${SSH_HOST} ..."
if ssh -o StrictHostKeyChecking=no -o ConnectTimeout=10 "${SSH_HOST}" "echo OK" 2>/dev/null; then
    echo "✅ SSH 连接成功"
else
    echo ""
    echo "⚠️  SSH 连接失败，请确认:"
    echo "   ① P600 能访问外网"
    echo "   ② 密码为: pdl@#YwC\$WRWFyHKxC8nyu!4"
    echo ""
    echo "   手动测试: ssh ${SSH_HOST}"
    echo ""
    read -p "是否继续安装服务？（y/n）" -n 1 -r
    echo
    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
        exit 1
    fi
fi

# 检查 sshpass
SSHPASS_CMD=""
if command -v sshpass &> /dev/null; then
    SSHPASS_CMD="sshpass -p 'pdl@#YwC\$WRWFyHKxC8nyu!4'"
    echo "✅ 已安装 sshpass，将使用密码自动登录"
else
    echo ""
    echo "⚠️  未安装 sshpass，需要先配置 SSH 密钥登录"
    echo "   执行以下命令配置免密登录:"
    echo ""
    echo "   ssh-copy-id ${SSH_HOST}"
    echo "   # 密码: pdl@#YwC\$WRWFyHKxC8nyu!4"
    echo ""
fi

# 创建 systemd 服务
echo ""
echo "📝 创建系统服务 ${SERVICE_NAME} ..."

cat > "${SERVICE_PATH}" << SERVICEEOF
[Unit]
Description=ROSbridge SSH Tunnel - P600 to Cloud Server
After=network-online.target
Wants=network-online.target
StartLimitIntervalSec=60
StartLimitBurst=5

[Service]
Type=simple
ExecStart=/bin/bash -c '${SSHPASS_CMD} /usr/bin/ssh -NT \
  -o ServerAliveInterval=30 \
  -o ServerAliveCountMax=3 \
  -o StrictHostKeyChecking=no \
  -o ExitOnForwardFailure=yes \
  -R ${SSH_PORT}:localhost:${LOCAL_PORT} \
  ${SSH_HOST}'

Restart=always
RestartSec=10
User=root

[Install]
WantedBy=multi-user.target
SERVICEEOF

echo "✅ 服务文件已创建"

# 重载 systemd
echo "🔄 重载 systemd 配置..."
systemctl daemon-reload

# 启用服务
echo "🔗 启用开机自启..."
systemctl enable "${SERVICE_NAME}"

# 启动服务
echo "🚀 启动隧道服务..."
systemctl restart "${SERVICE_NAME}"

# 等待 3 秒
sleep 3

# 检查状态
echo ""
echo "📊 服务状态:"
systemctl status "${SERVICE_NAME}" --no-pager | head -12

echo ""
echo "========================================="
echo "  ✅ 安装完成！"
echo "========================================="
echo ""
echo "  服务管理命令:"
echo "    查看状态: sudo systemctl status ${SERVICE_NAME}"
echo "    启动:     sudo systemctl start ${SERVICE_NAME}"
echo "    停止:     sudo systemctl stop ${SERVICE_NAME}"
echo "    重启:     sudo systemctl restart ${SERVICE_NAME}"
echo "    查看日志: sudo journalctl -u ${SERVICE_NAME} -f"
echo ""
echo "  网页连接地址: ws://121.41.216.243:${SSH_PORT}"
echo ""