package viral

import (
	"context"
	"strings"
	"time"

	"haixun-backend/internal/library/placement"
	"haixun-backend/internal/library/websearch"
)

const maxInspireTrendSnippets = 14

func CollectMissionInspireTrends(
	ctx context.Context,
	client websearch.Client,
	member placement.MemberContext,
	personaBrief, styleBenchmark string,
) []MissionInspireTrendSnippet {
	if client == nil || !client.Enabled() {
		return nil
	}
	queries := InspireTrendSearchQueries(personaBrief, styleBenchmark)
	out := make([]MissionInspireTrendSnippet, 0, maxInspireTrendSnippets)
	seen := map[string]struct{}{}

	for _, query := range queries {
		if len(out) >= maxInspireTrendSnippets {
			break
		}
		res, err := client.Search(ctx, websearch.SearchOptions{
			Query:              query,
			Limit:              5,
			Mode:               websearch.ModeKnowledgeExpand,
			Country:            member.BraveCountry,
			SearchLang:         member.BraveSearchLang,
			UserLocation:       member.ExaUserLocation,
			StartPublishedDate: placement.FormatPublishedAfterISO(7, time.Now().UTC()),
		})
		if err != nil || res.Status != "success" || len(res.Results) == 0 {
			continue
		}
		for _, item := range res.Results {
			if len(out) >= maxInspireTrendSnippets {
				break
			}
			title := strings.TrimSpace(item.Title)
			snippet := strings.TrimSpace(item.Snippet)
			if title == "" && snippet == "" {
				continue
			}
			if looksLikeNewsResult(title, snippet, item.URL) {
				continue
			}
			key := strings.ToLower(title + "|" + snippet)
			if _, ok := seen[key]; ok {
				continue
			}
			seen[key] = struct{}{}
			out = append(out, MissionInspireTrendSnippet{
				Query:   query,
				Title:   title,
				Snippet: snippet,
				URL:     strings.TrimSpace(item.URL),
			})
		}
	}
	return out
}

func looksLikeNewsResult(title, snippet, url string) bool {
	text := strings.ToLower(title + " " + snippet + " " + url)
	newsSignals := []string{"新聞", "快訊", "中央社", "聯合新聞", "ettoday", "tvbs", "setn", "ctwant", "chinatimes", "ltn.com", "news"}
	socialSignals := []string{"threads", "dcard", "ptt", "請問", "心得", "推薦", "有人", "怎麼辦", "討論", "留言"}
	newsScore := 0
	for _, signal := range newsSignals {
		if strings.Contains(text, strings.ToLower(signal)) {
			newsScore++
		}
	}
	if newsScore == 0 {
		return false
	}
	for _, signal := range socialSignals {
		if strings.Contains(text, strings.ToLower(signal)) {
			return false
		}
	}
	return true
}