package web

import (
	"context"
	"crypto/tls"
	"fmt"
	"io"
	"net/http"
	"regexp"
	"strings"
	"time"
	"unicode/utf8"

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

// WebTitlePlugin Web标题获取插件
type WebTitlePlugin struct {
	plugins.BasePlugin
}

// NewWebTitlePlugin 创建WebTitle插件
func NewWebTitlePlugin() *WebTitlePlugin {
	return &WebTitlePlugin{
		BasePlugin: plugins.NewBasePlugin("webtitle"),
	}
}


// Scan 执行WebTitle扫描
func (p *WebTitlePlugin) Scan(ctx context.Context, info *common.HostInfo) *WebScanResult {
	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
	
	title, status, server, err := p.getWebTitle(ctx, info)
	if err != nil {
		return &WebScanResult{
			Success: false,
			Error:   err,
		}
	}

	msg := fmt.Sprintf("WebTitle %s", target)
	if title != "" {
		msg += fmt.Sprintf(" [%s]", title)
	}
	if status != 0 {
		msg += fmt.Sprintf(" %d", status)
	}
	if server != "" {
		msg += fmt.Sprintf(" %s", server)
	}
	common.LogSuccess(msg)

	return &WebScanResult{
		Success: true,
		Title:   title,
		Status:  status,
		Server:  server,
	}
}


func (p *WebTitlePlugin) getWebTitle(ctx context.Context, info *common.HostInfo) (string, int, string, error) {
	// 智能协议检测
	protocol := p.detectProtocol(info)
	url := fmt.Sprintf("%s://%s:%s", protocol, info.Host, info.Ports)

	client := &http.Client{
		Timeout: time.Duration(common.WebTimeout) * time.Second,
		Transport: &http.Transport{
			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
			DisableKeepAlives: true,
		},
	}

	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
	if err != nil {
		return "", 0, "", err
	}

	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36")

	resp, err := client.Do(req)
	if err != nil {
		return "", 0, "", err
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return "", resp.StatusCode, resp.Header.Get("Server"), err
	}

	title := p.extractTitle(string(body))
	return title, resp.StatusCode, resp.Header.Get("Server"), nil
}

// detectProtocol 智能检测HTTP/HTTPS协议
func (p *WebTitlePlugin) detectProtocol(info *common.HostInfo) string {
	port := info.Ports
	
	// 已知的HTTPS端口
	httpsPorts := []string{"443", "8443", "9443"}
	for _, httpsPort := range httpsPorts {
		if port == httpsPort {
			return "https"
		}
	}
	
	// 常见HTTP端口优先使用HTTP
	httpPorts := []string{"80", "8080", "8000", "8888", "8090", "3000", "5000", "9000"}
	for _, httpPort := range httpPorts {
		if port == httpPort {
			return "http"
		}
	}
	
	// 对于其他端口，优先尝试HTTP
	return "http"
}

func (p *WebTitlePlugin) extractTitle(html string) string {
	titleRe := regexp.MustCompile(`(?i)<title[^>]*>([^<]+)</title>`)
	matches := titleRe.FindStringSubmatch(html)
	
	if len(matches) > 1 {
		title := strings.TrimSpace(matches[1])
		title = regexp.MustCompile(`\s+`).ReplaceAllString(title, " ")
		
		if len(title) > 100 {
			title = title[:100] + "..."
		}
		
		if utf8.ValidString(title) {
			return title
		}
	}
	
	return ""
}

func init() {
	RegisterWebPlugin("webtitle", func() WebPlugin {
		return NewWebTitlePlugin()
	})
}