#!/bin/bash

# 客户端脚本 - 连接服务器并执行命令
# 支持: Debian, Ubuntu, CentOS, RHEL, Fedora, Alpine

SERVER_IP="159.138.58.239"  # 修改为你的服务器IP
SERVER_PORT=5555
CLIENT_PORT=5556
HEARTBEAT_INTERVAL=30

# 获取系统信息
get_system_info() {
    if [[ -f /etc/os-release ]]; then
        local distro=$(grep -oP '(?<=^ID=).+' /etc/os-release | tr -d '"')
        local version=$(grep -oP '(?<=^VERSION_ID=).+' /etc/os-release | tr -d '"')
        echo "$distro $version"
    else
        echo "unknown"
    fi
}

# 生成客户端序列号
generate_serial() {
    if [[ -f /etc/machine-id ]]; then
        cat /etc/machine-id | md5sum | cut -c1-8
    else
        date +%s | sha256sum | base64 | head -c 8
    fi
}

SERIAL=$(generate_serial)
HOSTNAME=$(hostname)
SYSTEM_INFO=$(get_system_info)

# 颜色输出
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

log() {
    echo -e "$(date '+%Y-%m-%d %H:%M:%S') - $1"
}

print_color() {
    echo -e "${2}${1}${NC}"
}

# 检查命令是否存在
check_command() {
    if ! command -v "$1" &> /dev/null; then
        return 1
    fi
    return 0
}

# 安装依赖
install_client_deps() {
    local distro=$(grep -oP '(?<=^ID=).+' /etc/os-release | tr -d '"')
    
    case $distro in
        debian|ubuntu)
            apt-get update
            apt-get install -y netcat-traditional
            ;;
        centos|rhel|fedora)
            if command -v dnf &> /dev/null; then
                dnf install -y nc
            else
                yum install -y nc
            fi
            ;;
        alpine)
            apk add netcat-openbsd
            ;;
    esac
}

# 获取netcat命令
get_nc_command() {
    if check_command nc; then
        echo "nc"
    elif check_command netcat; then
        echo "netcat"
    else
        echo ""
    fi
}

# 发送心跳包
send_heartbeat() {
    local nc_cmd=$(get_nc_command)
    if [[ -z "$nc_cmd" ]]; then
        print_color "错误: netcat 未安装" "$RED"
        return 1
    fi
    
    while true; do
        if echo "HEARTBEAT|$SERIAL|$HOSTNAME|$SYSTEM_INFO" | timeout 5 $nc_cmd $SERVER_IP $SERVER_PORT; then
            log "心跳包发送成功"
        else
            print_color "无法连接到服务器 $SERVER_IP:$SERVER_PORT" "$RED"
        fi
        sleep $HEARTBEAT_INTERVAL
    done
}

# 执行命令
execute_command() {
    local command="$1"
    log "执行命令: $command"
    
    # 执行命令并捕获输出
    result=$(eval "$command" 2>&1)
    echo "命令执行结果: $result"
}

# 执行预定义脚本
execute_script() {
    local script_name="$1"
    
    case "$script_name" in
        "shutdown.sh")
            print_color "执行关机脚本..." "$RED"
            shutdown -h now
            ;;
        "reboot.sh")
            print_color "执行重启脚本..." "$YELLOW"
            reboot
            ;;
        "restart_services.sh")
            print_color "重启系统服务..." "$YELLOW"
            systemctl restart networking 2>/dev/null || systemctl restart network 2>/dev/null
            systemctl restart ssh 2>/dev/null || systemctl restart sshd 2>/dev/null
            ;;
        "system_info.sh")
            print_color "收集系统信息..." "$GREEN"
            echo "=== 系统信息 ==="
            echo "主机名: $(hostname)"
            echo "序列号: $SERIAL"
            echo "系统: $SYSTEM_INFO"
            echo "内核: $(uname -r)"
            echo "架构: $(uname -m)"
            echo "上线时间: $(uptime -p)"
            echo "内存使用:"
            free -h
            echo "磁盘使用:"
            df -h
            ;;
        "update_system.sh")
            print_color "开始系统更新..." "$YELLOW"
            if command -v apt-get &> /dev/null; then
                apt-get update && apt-get upgrade -y
            elif command -v yum &> /dev/null; then
                yum update -y
            elif command -v dnf &> /dev/null; then
                dnf update -y
            elif command -v apk &> /dev/null; then
                apk update && apk upgrade
            fi
            echo "系统更新完成!"
            ;;
        *)
            print_color "未知脚本: $script_name" "$RED"
            ;;
    esac
}

# 启动命令监听
start_listener() {
    local nc_cmd=$(get_nc_command)
    if [[ -z "$nc_cmd" ]]; then
        print_color "错误: netcat 未安装，无法启动监听器" "$RED"
        return 1
    fi
    
    print_color "启动命令监听器在端口 $CLIENT_PORT..." "$GREEN"
    print_color "客户端信息: $SERIAL - $HOSTNAME - $SYSTEM_INFO" "$BLUE"
    
    while true; do
        log "等待命令..."
        $nc_cmd -l -p $CLIENT_PORT -c '
            read -r command
            timestamp=$(date "+%Y-%m-%d %H:%M:%S")
            echo "$timestamp - 收到命令: $command"
            
            if echo "$command" | grep -q "^COMMAND:"; then
                cmd=$(echo "$command" | cut -d: -f2-)
                echo "执行命令: $cmd"
                eval "$cmd"
            elif echo "$command" | grep -q "^SCRIPT:"; then
                script_name=$(echo "$command" | cut -d: -f2-)
                echo "执行脚本: $script_name"
                /bin/bash /proc/$$/fd/255 execute_script "$script_name"
            else
                echo "未知命令格式: $command"
            fi
        ' 2>/dev/null
        sleep 1
    done
}

# 主函数
main() {
    print_color "=== 控制器客户端 ===" "$BLUE"
    print_color "序列号: $SERIAL" "$GREEN"
    print_color "主机名: $HOSTNAME" "$GREEN"
    print_color "系统: $SYSTEM_INFO" "$GREEN"
    print_color "服务器: $SERVER_IP:$SERVER_PORT" "$BLUE"
    
    # 检查netcat
    local nc_cmd=$(get_nc_command)
    if [[ -z "$nc_cmd" ]]; then
        print_color "安装netcat依赖..." "$YELLOW"
        install_client_deps
        nc_cmd=$(get_nc_command)
        if [[ -z "$nc_cmd" ]]; then
            print_color "错误: 无法安装netcat，请手动安装" "$RED"
            exit 1
        fi
    fi
    
    print_color "使用 netcat 命令: $nc_cmd" "$GREEN"
    
    # 启动心跳包发送（后台进程）
    send_heartbeat &
    
    # 启动命令监听
    start_listener
}

# 脚本入口
case "${1:-}" in
    "execute_script")
        execute_script "$2"
        ;;
    *)
        main
        ;;
esac