package pipeline

import (
	"context"
	"log"
	"net/url"
	"regexp"
	"time"

	"spider/internal/model"
	"spider/internal/search"

	"gorm.io/gorm"
)

// SearchPhase Phase 2: 搜索引擎采集
type SearchPhase struct {
	db       *gorm.DB
	serper   *search.SerperClient
	settings Settings
	reporter ProgressReporter
}

// NewSearchPhase creates a new SearchPhase.
func NewSearchPhase(db *gorm.DB, serper *search.SerperClient, settings Settings) *SearchPhase {
	return &SearchPhase{
		db:       db,
		serper:   serper,
		settings: settings,
	}
}

func (p *SearchPhase) Name() string { return "search" }

func (p *SearchPhase) Run(ctx context.Context, task *model.Task, opts *Options) error {
	if p.serper == nil {
		log.Println("[search] no serper client configured, skipping")
		return nil
	}

	// 取 active 关键词
	var keywords []model.ManagedKeyword
	q := p.db.Where("status = ?", "active")
	if opts.TestRun != nil && opts.TestRun.ItemLimit > 0 {
		q = q.Limit(opts.TestRun.ItemLimit)
	}
	q.Find(&keywords)

	total := len(keywords)
	channelCount, navCount := 0, 0

	for i, kw := range keywords {
		if isContextDone(ctx) {
			break
		}

		if p.reporter != nil {
			p.reporter("search", i+1, total, "搜索: "+kw.Keyword)
		}

		results, err := p.serper.Search(ctx, kw.Keyword)
		if err != nil {
			log.Printf("[search] keyword=%s err=%v", kw.Keyword, err)
			continue
		}

		for _, r := range results {
			switch search.ClassifyURL(r.URL) {
			case "tg_channel":
				username := extractTGUsername(r.URL)
				if username == "" {
					continue
				}
				ch := &model.Channel{
					Username:     username,
					Source:       "search",
					SourceDetail: kw.Keyword,
					Status:       "pending",
				}
				result := p.db.Where(model.Channel{Username: username}).FirstOrCreate(ch)
				if result.RowsAffected > 0 {
					channelCount++
				}

			case "nav_site":
				domain := extractDomain(r.URL)
				site := &model.NavSite{
					URL:    r.URL,
					Domain: domain,
					Source: kw.Keyword,
					Status: "pending",
				}
				result := p.db.Where("url = ?", r.URL).FirstOrCreate(site)
				if result.RowsAffected > 0 {
					navCount++
				}
			}
		}

		// 关键词间 sleep 2s
		select {
		case <-ctx.Done():
			return nil
		case <-time.After(2 * time.Second):
		}
	}

	log.Printf("[search] done: %d channels, %d nav_sites found", channelCount, navCount)
	return nil
}

// extractTGUsername 从 t.me/username 或 telegram.me/username 提取用户名
func extractTGUsername(rawURL string) string {
	re := regexp.MustCompile(`(?:t(?:elegram)?\.me)/([a-zA-Z][a-zA-Z0-9_]{4,31})`)
	m := re.FindStringSubmatch(rawURL)
	if len(m) > 1 {
		return m[1]
	}
	return ""
}

// extractDomain 从 URL 中提取域名
func extractDomain(rawURL string) string {
	u, err := url.Parse(rawURL)
	if err != nil {
		return ""
	}
	return u.Hostname()
}