package pop3

import (
	"context"
	"fmt"
	"strings"

	"github.com/shadow1ng/fscan/common"
	"github.com/shadow1ng/fscan/common/i18n"
	"github.com/shadow1ng/fscan/plugins/base"
)

// POP3Plugin POP3插件实现
type POP3Plugin struct {
	*base.ServicePlugin
	exploiter *POP3Exploiter
}

// NewPOP3Plugin 创建POP3插件
func NewPOP3Plugin() *POP3Plugin {
	// 插件元数据
	metadata := &base.PluginMetadata{
		Name:        "pop3",
		Version:     "2.0.0",
		Author:      "fscan-team",
		Description: "POP3邮件服务扫描和利用插件",
		Category:    "service",
		Ports:       []int{110, 995}, // POP3常用端口
		Protocols:   []string{"tcp"},
		Tags:        []string{"pop3", "email", "weak-password", "tls"},
	}
	
	// 创建连接器和服务插件
	connector := NewPOP3Connector()
	servicePlugin := base.NewServicePlugin(metadata, connector)
	
	// 创建POP3插件
	plugin := &POP3Plugin{
		ServicePlugin: servicePlugin,
		exploiter:     NewPOP3Exploiter(),
	}
	
	// 设置能力
	plugin.SetCapabilities([]base.Capability{
		base.CapWeakPassword,
	})
	
	return plugin
}

// Scan 重写扫描方法，进行POP3服务扫描
func (p *POP3Plugin) Scan(ctx context.Context, info *common.HostInfo) (*base.ScanResult, error) {
	// 如果禁用了暴力破解，只进行服务识别
	if common.DisableBrute {
		return p.performServiceIdentification(ctx, info)
	}
	
	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
	
	// 生成凭据进行暴力破解
	credentials := p.generateCredentials()
	
	// 遍历凭据进行测试
	for _, cred := range credentials {
		result, err := p.ScanCredential(ctx, info, cred)
		if err == nil && result.Success {
			// 认证成功
			tlsStatus := ""
			if result.Extra["tls"] == true {
				tlsStatus = " (TLS)"
			}
			
			common.LogSuccess(i18n.GetText("pop3_weak_pwd_success", target, cred.Username, cred.Password) + tlsStatus)
			
			return &base.ScanResult{
				Success:     true,
				Service:     "POP3",
				Credentials: []*base.Credential{cred},
				Banner:      result.Banner,
				Extra: map[string]interface{}{
					"service":  "POP3",
					"port":     info.Ports,
					"username": cred.Username,
					"password": cred.Password,
					"type":     "weak-password",
					"tls":      result.Extra["tls"],
				},
			}, nil
		}
	}
	
	// 所有凭据都失败，但可能识别到了POP3服务
	return p.performServiceIdentification(ctx, info)
}

// generateCredentials 生成POP3凭据
func (p *POP3Plugin) generateCredentials() []*base.Credential {
	var credentials []*base.Credential
	
	// 获取POP3用户名字典
	usernames := common.Userdict["pop3"]
	if len(usernames) == 0 {
		usernames = []string{"admin", "root", "test", "mail", "postmaster", "user"}
	}
	
	// 获取密码字典
	passwords := common.Passwords
	if len(passwords) == 0 {
		passwords = []string{"", "admin", "password", "123456", "admin123", "test123", "root123"}
	}
	
	// 生成用户名密码组合
	for _, username := range usernames {
		for _, password := range passwords {
			// 替换密码中的用户名占位符
			actualPassword := strings.Replace(password, "{user}", username, -1)
			
			credentials = append(credentials, &base.Credential{
				Username: username,
				Password: actualPassword,
			})
		}
	}
	
	return credentials
}

// Exploit 使用exploiter执行利用
func (p *POP3Plugin) Exploit(ctx context.Context, info *common.HostInfo, creds *base.Credential) (*base.ExploitResult, error) {
	return p.exploiter.Exploit(ctx, info, creds)
}

// GetExploitMethods 获取利用方法
func (p *POP3Plugin) GetExploitMethods() []base.ExploitMethod {
	return p.exploiter.GetExploitMethods()
}

// IsExploitSupported 检查利用支持
func (p *POP3Plugin) IsExploitSupported(method base.ExploitType) bool {
	return p.exploiter.IsExploitSupported(method)
}

// performServiceIdentification 执行POP3服务识别（-nobr模式）
func (p *POP3Plugin) performServiceIdentification(ctx context.Context, info *common.HostInfo) (*base.ScanResult, error) {
	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
	
	// 尝试识别POP3服务
	connector := NewPOP3Connector()
	conn, err := connector.Connect(ctx, info)
	
	if err == nil && conn != nil {
		if pop3Conn, ok := conn.(*POP3Connection); ok {
			// 记录服务识别成功
			tlsStatus := ""
			if pop3Conn.isTLS {
				tlsStatus = " (TLS)"
			}
			common.LogSuccess(i18n.GetText("pop3_service_identified", target, pop3Conn.banner) + tlsStatus)
			
			connector.Close(conn)
			return &base.ScanResult{
				Success: true,
				Service: "POP3",
				Banner:  pop3Conn.banner,
				Extra: map[string]interface{}{
					"service": "POP3",
					"port":    info.Ports,
					"banner":  pop3Conn.banner,
					"tls":     pop3Conn.isTLS,
				},
			}, nil
		}
	}
	
	// 如果无法识别为POP3，返回失败
	return &base.ScanResult{
		Success: false,
		Error:   fmt.Errorf("无法识别为POP3服务"),
	}, nil
}

// =============================================================================
// 插件注册
// =============================================================================

// RegisterPOP3Plugin 注册POP3插件
func RegisterPOP3Plugin() {
	factory := base.NewSimplePluginFactory(
		&base.PluginMetadata{
			Name:        "pop3",
			Version:     "2.0.0",
			Author:      "fscan-team",
			Description: "POP3邮件服务扫描和利用插件",
			Category:    "service",
			Ports:       []int{110, 995}, // POP3常用端口
			Protocols:   []string{"tcp"},
			Tags:        []string{"pop3", "email", "weak-password", "tls"},
		},
		func() base.Plugin {
			return NewPOP3Plugin()
		},
	)
	
	base.GlobalPluginRegistry.Register("pop3", factory)
}

// 自动注册
func init() {
	RegisterPOP3Plugin()
}