#!/bin/bash
set -e

CONFIG_DIR="/etc/tun2socks"
CONFIG_FILE="$CONFIG_DIR/config.yaml"
SERVICE_FILE="/etc/systemd/system/tun2socks.service"
BINARY_PATH="/usr/local/bin/tun2socks"

# 检查 root
if [ "$EUID" -ne 0 ]; then
    echo "请使用 root 运行脚本"
    exit 1
fi

# 安装 tun2socks
install_tun2socks() {
    if ! command -v tun2socks &>/dev/null; then
        echo "检测到 tun2socks 未安装，正在下载..."
        REPO="heiher/hev-socks5-tunnel"

        # 获取系统架构
        ARCH=$(uname -m)
        case "$ARCH" in
            x86_64)
                ARCH_TAG="linux-x86_64"
                ;;
            aarch64 | arm64)
                ARCH_TAG="linux-arm64"
                ;;
            armv7l)
                ARCH_TAG="linux-armv7"
                ;;
            *)
                echo "不支持的架构: $ARCH"
                exit 1
                ;;
        esac

        DOWNLOAD_URL=$(curl -s https://api.github.com/repos/$REPO/releases/latest \
            | grep "browser_download_url" | grep "$ARCH_TAG" | cut -d '"' -f 4)
        if [ -z "$DOWNLOAD_URL" ]; then
            echo "无法获取 tun2socks 下载链接，请手动安装"
            exit 1
        fi

        curl -L -o "$BINARY_PATH" "$DOWNLOAD_URL"
        chmod +x "$BINARY_PATH"
        echo "tun2socks 安装完成 ($ARCH)"
    else
        echo "tun2socks 已安装"
    fi
}

# 配置 Socks5
configure_tun2socks() {
    mkdir -p "$CONFIG_DIR"
    read -rp "请输入Socks5服务器地址 [默认127.0.0.1]: " SOCKS_ADDRESS
    SOCKS_ADDRESS=${SOCKS_ADDRESS:-127.0.0.1}
    read -rp "请输入Socks5服务器端口 [默认7890]: " SOCKS_PORT
    SOCKS_PORT=${SOCKS_PORT:-7890}

    cat > "$CONFIG_FILE" <<EOF
tunnel:
  name: tun0
  mtu: 8500
  multi-queue: true
  ipv4: 198.18.0.1

socks5:
  address: '$SOCKS_ADDRESS'
  port: $SOCKS_PORT
  udp: 'udp'
  mark: 438
EOF
    echo "配置文件生成完成: $CONFIG_FILE"
}

# 创建 systemd 服务
create_systemd_service() {
    cat > "$SERVICE_FILE" <<EOF
[Unit]
Description=Tun2Socks Tunnel Service
After=network.target

[Service]
Type=simple
ExecStart=$BINARY_PATH $CONFIG_FILE
ExecStartPost=/bin/sleep 1
ExecStartPost=/sbin/ip rule add fwmark 438 lookup main pref 10
ExecStartPost=/sbin/ip -6 rule add fwmark 438 lookup main pref 10
ExecStartPost=/sbin/ip route add default dev tun0 table 20
ExecStartPost=/sbin/ip rule add lookup 20 pref 20
ExecStartPost=/sbin/ip rule add to 127.0.0.0/8 lookup main pref 16
ExecStartPost=/sbin/ip rule add to 10.0.0.0/8 lookup main pref 16
ExecStartPost=/sbin/ip rule add to 172.16.0.0/12 lookup main pref 16
ExecStartPost=/sbin/ip rule add to 192.168.0.0/16 lookup main pref 16

ExecStop=/sbin/ip rule del fwmark 438 lookup main pref 10 || true
ExecStop=/sbin/ip -6 rule del fwmark 438 lookup main pref 10 || true
ExecStop=/sbin/ip route del default dev tun0 table 20 || true
ExecStop=/sbin/ip rule del lookup 20 pref 20 || true
ExecStop=/sbin/ip rule del to 127.0.0.0/8 lookup main pref 16 || true
ExecStop=/sbin/ip rule del to 10.0.0.0/8 lookup main pref 16 || true
ExecStop=/sbin/ip rule del to 172.16.0.0/12 lookup main pref 16 || true
ExecStop=/sbin/ip rule del to 192.168.0.0/16 lookup main pref 16 || true

Restart=always

[Install]
WantedBy=multi-user.target
EOF

    systemctl daemon-reload
    systemctl enable tun2socks.service
    echo "systemd 服务创建完成并已设置开机自启"
}

# 菜单操作
menu() {
    while true; do
        echo "===================================="
        echo " tun2socks 管理脚本"
        echo "===================================="
        echo "1) 安装 & 配置 tun2socks"
        echo "2) 启动服务"
        echo "3) 停止服务"
        echo "4) 重启服务"
        echo "5) 查看状态"
        echo "6) 卸载服务"
        echo "0) 退出"
        echo "===================================="
        read -rp "请选择操作: " choice
        case "$choice" in
            1)
                install_tun2socks
                configure_tun2socks
                create_systemd_service
                systemctl start tun2socks.service
                echo "tun2socks 已启动"
                ;;
            2)
                systemctl start tun2socks.service
                echo "服务已启动"
                ;;
            3)
                systemctl stop tun2socks.service
                echo "服务已停止"
                ;;
            4)
                systemctl restart tun2socks.service
                echo "服务已重启"
                ;;
            5)
                systemctl status tun2socks.service
                ;;
            6)
                systemctl stop tun2socks.service || true
                systemctl disable tun2socks.service || true
                rm -f "$SERVICE_FILE"
                rm -rf "$CONFIG_DIR"
                rm -f "$BINARY_PATH"
                systemctl daemon-reload
                echo "服务已卸载"
                ;;
            0)
                exit 0
                ;;
            *)
                echo "无效选择"
                ;;
        esac
    done
}

menu