package main

import (
	"fmt"
	"log"
	"net/http"
	"net/url"
	"strings"

	"github.com/PuerkitoBio/goquery"
)

func PerformGoogleTextSearch(query, safe, lang string, page int) ([]TextSearchResult, error) {
	const resultsPerPage = 10
	var results []TextSearchResult

	client := &http.Client{}
	searchURL := buildSearchURL(query, safe, lang, page, resultsPerPage)

	req, err := http.NewRequest("GET", searchURL, nil)
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %v", err)
	}

	// User Agent generation
	TextUserAgent, err := GetUserAgent("Text-Search")
	if err != nil {
		fmt.Println("Error:", err)
		return nil, err
	}

	if debugMode {
		fmt.Println("Generated User Agent (text):", TextUserAgent)
	}

	req.Header.Set("User-Agent", TextUserAgent)

	resp, err := client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("making request: %v", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
	}

	doc, err := goquery.NewDocumentFromReader(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("loading HTML document: %v", err)
	}

	results = parseResults(doc)

	if len(results) == 0 {
		if debugMode {
			log.Println("No results found from Google")
		}
	}

	return results, nil
}

func buildSearchURL(query, safe, lang string, page, resultsPerPage int) string {
	safeParam := "&safe=off"
	if safe == "active" {
		safeParam = "&safe=active"
	}

	langParam := ""
	if lang != "" {
		langParam = "&lr=" + lang
	}

	startIndex := (page - 1) * resultsPerPage
	return fmt.Sprintf("https://www.google.com/search?q=%s%s%s&udm=14&start=%d", url.QueryEscape(query), safeParam, langParam, startIndex)
}

func parseResults(doc *goquery.Document) []TextSearchResult {
	var results []TextSearchResult

	doc.Find(".yuRUbf").Each(func(i int, s *goquery.Selection) {
		link := s.Find("a")
		href, exists := link.Attr("href")
		if !exists {
			if debugMode {
				log.Printf("No href attribute found for result %d\n", i)
			}
			return
		}

		header := link.Find("h3").Text()
		header = strings.TrimSpace(strings.TrimSuffix(header, "›"))

		description := ""
		descSelection := doc.Find(".VwiC3b").Eq(i)
		if descSelection.Length() > 0 {
			description = descSelection.Text()
		}

		result := TextSearchResult{
			URL:         href,
			Header:      header,
			Description: description,
		}
		results = append(results, result)
		if debugMode {
			log.Printf("Google result: %+v\n", result)
		}
	})

	return results
}