package services

import (
	"context"
	"fmt"
	"net"
	"strings"
	"time"

	"github.com/shadow1ng/fscan/common"
)

type MemcachedPlugin struct {
	name  string
	ports []int
}

func NewMemcachedPlugin() *MemcachedPlugin {
	return &MemcachedPlugin{
		name:  "memcached",
		ports: []int{11211, 11212, 11213},
	}
}

func (p *MemcachedPlugin) GetName() string {
	return p.name
}

func (p *MemcachedPlugin) GetPorts() []int {
	return p.ports
}

func (p *MemcachedPlugin) Scan(ctx context.Context, info *common.HostInfo) *ScanResult {
	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)

	if common.DisableBrute {
		return p.identifyService(ctx, info)
	}

	conn := p.connectToMemcached(ctx, info)
	if conn == nil {
		return &ScanResult{
			Success: false,
			Service: "memcached",
			Error:   fmt.Errorf("Memcached服务连接失败"),
		}
	}
	defer conn.Close()

	if p.testBasicCommand(conn) {
		common.LogSuccess(fmt.Sprintf("Memcached %s 未授权访问", target))
		return &ScanResult{
			Success: true,
			Service: "memcached",
			Banner:  "未授权访问",
		}
	}

	return &ScanResult{
		Success: false,
		Service: "memcached",
		Error:   fmt.Errorf("Memcached服务连接失败"),
	}
}


func (p *MemcachedPlugin) connectToMemcached(ctx context.Context, info *common.HostInfo) net.Conn {
	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
	timeout := time.Duration(common.Timeout) * time.Second

	conn, err := net.DialTimeout("tcp", target, timeout)
	if err != nil {
		return nil
	}

	conn.SetDeadline(time.Now().Add(timeout))

	return conn
}

func (p *MemcachedPlugin) testBasicCommand(conn net.Conn) bool {
	timeout := time.Duration(common.Timeout) * time.Second
	
	conn.SetWriteDeadline(time.Now().Add(timeout))
	if _, err := conn.Write([]byte("version\r\n")); err != nil {
		return false
	}

	conn.SetReadDeadline(time.Now().Add(timeout))
	response := make([]byte, 1024)
	n, err := conn.Read(response)
	if err != nil {
		return false
	}

	responseStr := string(response[:n])
	return strings.Contains(responseStr, "VERSION") || strings.Contains(responseStr, "memcached")
}








func (p *MemcachedPlugin) identifyService(ctx context.Context, info *common.HostInfo) *ScanResult {
	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)

	conn := p.connectToMemcached(ctx, info)
	if conn == nil {
		return &ScanResult{
			Success: false,
			Service: "memcached",
			Error:   fmt.Errorf("无法连接到Memcached服务"),
		}
	}
	defer conn.Close()

	banner := "Memcached"
	if p.testBasicCommand(conn) {
		common.LogSuccess(fmt.Sprintf("Memcached %s %s", target, banner))
		return &ScanResult{
			Success: true,
			Service: "memcached",
			Banner:  banner,
		}
	}

	return &ScanResult{
		Success: false,
		Service: "memcached",
		Error:   fmt.Errorf("无法识别为Memcached服务"),
	}
}

func init() {
	RegisterPlugin("memcached", func() Plugin {
		return NewMemcachedPlugin()
	})
}