package services

import (
	"context"
	"database/sql"
	"fmt"
	"strings"
	"time"

	_ "github.com/denisenkom/go-mssqldb"
	"github.com/shadow1ng/fscan/common"
	"github.com/shadow1ng/fscan/plugins"
)

type MSSQLPlugin struct {
	plugins.BasePlugin
}

func NewMSSQLPlugin() *MSSQLPlugin {
	return &MSSQLPlugin{
		BasePlugin: plugins.NewBasePlugin("mssql"),
	}
}



func (p *MSSQLPlugin) 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)
	}

	credentials := GenerateCredentials("mssql")
	if len(credentials) == 0 {
		return &ScanResult{
			Success: false,
			Service: "mssql",
			Error:   fmt.Errorf("没有可用的测试凭据"),
		}
	}

	for _, cred := range credentials {
		if db := p.testCredential(ctx, info, cred); db != nil {
			db.Close()
			
			common.LogSuccess(fmt.Sprintf("MSSQL %s %s:%s", target, cred.Username, cred.Password))

			return &ScanResult{
				Success:  true,
				Service:  "mssql",
				Username: cred.Username,
				Password: cred.Password,
			}
		}
	}

	return &ScanResult{
		Success: false,
		Service: "mssql",
		Error:   fmt.Errorf("未发现弱密码"),
	}
}


func (p *MSSQLPlugin) testCredential(ctx context.Context, info *common.HostInfo, cred Credential) *sql.DB {
	connStr := fmt.Sprintf("server=%s;user id=%s;password=%s;port=%s;database=master;connection timeout=%d",
		info.Host, cred.Username, cred.Password, info.Ports, common.Timeout)

	db, err := sql.Open("mssql", connStr)
	if err != nil {
		return nil
	}

	db.SetConnMaxLifetime(time.Duration(common.Timeout) * time.Second)
	db.SetMaxOpenConns(1)
	db.SetMaxIdleConns(0)

	pingCtx, cancel := context.WithTimeout(ctx, time.Duration(common.Timeout)*time.Second)
	defer cancel()

	err = db.PingContext(pingCtx)
	if err != nil {
		db.Close()
		return nil
	}

	return db
}







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

	connStr := fmt.Sprintf("server=%s;user id=invalid;password=invalid;port=%s;database=master;connection timeout=%d",
		info.Host, info.Ports, common.Timeout)

	db, err := sql.Open("mssql", connStr)
	if err != nil {
		return &ScanResult{
			Success: false,
			Service: "mssql",
			Error:   err,
		}
	}
	defer db.Close()

	pingCtx, cancel := context.WithTimeout(ctx, time.Duration(common.Timeout)*time.Second)
	defer cancel()

	err = db.PingContext(pingCtx)
	
	var banner string
	if err != nil && (strings.Contains(strings.ToLower(err.Error()), "login failed") ||
					 strings.Contains(strings.ToLower(err.Error()), "mssql") ||
					 strings.Contains(strings.ToLower(err.Error()), "sql server")) {
		banner = "MSSQL"
	} else if err == nil {
		banner = "MSSQL"
	} else {
		return &ScanResult{
			Success: false,
			Service: "mssql",
			Error:   fmt.Errorf("无法识别为MSSQL服务"),
		}
	}

	common.LogSuccess(fmt.Sprintf("MSSQL %s %s", target, banner))

	return &ScanResult{
		Success: true,
		Service: "mssql",
		Banner:  banner,
	}
}

func init() {
	// 使用高效注册方式：直接传递端口信息，避免实例创建
	RegisterPluginWithPorts("mssql", func() Plugin {
		return NewMSSQLPlugin()
	}, []int{1433, 1434})
}