package main

import (
    "fmt"
    "log"
    "math/rand"
    "net/http"
    "net/url"
    "strconv"
	"strings"
    "time"
    "html/template"

    "github.com/PuerkitoBio/goquery"
)

var funcs = template.FuncMap{
    "title": func(s string) string {
        return strings.Title(s)
    },
    "url_for": func(filename string) string {
        return "/" + filename
    },
}

var templates = template.Must(template.New("").Funcs(funcs).ParseFiles("templates/results.html"))

func main() {
    http.HandleFunc("/", handleSearch)
    http.HandleFunc("/search", handleSearch)
    fmt.Println("Server is listening on http://localhost:5000")
    log.Fatal(http.ListenAndServe(":5000", nil))
}

func handleSearch(w http.ResponseWriter, r *http.Request) {
    if r.Method == "GET" {
        http.ServeFile(w, r, "static/search.html")
        return
    }

    query := r.FormValue("q")
    if query == "" {
        http.ServeFile(w, r, "static/search.html")
        return
    }

    // Random user agent
    userAgents := []string{
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36",
        "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36",
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:107.0) Gecko/20100101 Firefox/107.0",
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36",
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:106.0) Gecko/20100101 Firefox/106.0",
        "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.1 Safari/605.1.15",
    }
    randIndex := rand.Intn(len(userAgents))
    userAgent := userAgents[randIndex]

    // Time
    start := time.Now()

    // Search query
    searchURL := "https://www.google.com/search?q=" + url.QueryEscape(query)
    req, err := http.NewRequest("GET", searchURL, nil)
    if err != nil {
        http.Error(w, "Failed to create request", http.StatusInternalServerError)
        return
    }
    req.Header.Set("User-Agent", userAgent)
    resp, err := http.DefaultClient.Do(req)
    if err != nil {
        http.Error(w, "Failed to fetch search results", http.StatusInternalServerError)
        return
    }
    defer resp.Body.Close()

    // Parse HTML
    doc, err := goquery.NewDocumentFromReader(resp.Body)
    if err != nil {
        http.Error(w, "Failed to parse HTML", http.StatusInternalServerError)
        return
    }

    // Retrieve links
    var results [][]string
    doc.Find(".yuRUbf").Each(func(i int, s *goquery.Selection) {
        link := s.Find("a")
        href, _ := link.Attr("href")
        title := link.Text()
        results = append(results, []string{href, title})
    })

    // Retrieve description
    var descriptions []string
    doc.Find(".VwiC3b").Each(func(i int, s *goquery.Selection) {
        desc := s.Text()
        descriptions = append(descriptions, desc)
    })

    // Retrieve kno-rdesc
    kno := ""
    knoLink := ""
    rdesc := doc.Find(".kno-rdesc")
    if rdesc.Length() > 0 {
        span := rdesc.Find("span")
        kno = span.Text()
        descLink := rdesc.Find("a")
        knoLink, _ = descLink.Attr("href")
    }

    // Retrieve featured snippet
    snip := ""
    snipSpan := doc.Find(".hgKElc")
    if snipSpan.Length() > 0 {
        snip = snipSpan.Text()
    }

    elapsed := time.Since(start)

    // Render template
    data := struct {
        Results       [][]string
        Title         string
        Query         string
        Fetched       string
        Snippet       string
        KnoRdesc      string
        RdescLink     string
        ElapsedTime   string
    }{
        Results:       results,
        Title:         query + " - TailsGo",
        Query:         query,
        Fetched:       fmt.Sprintf("Fetched the results in %.2f seconds", elapsed.Seconds()),
        Snippet:       snip,
        KnoRdesc:      kno,
        RdescLink:     knoLink,
        ElapsedTime:   strconv.FormatFloat(elapsed.Seconds(), 'f', 2, 64),
    }
    err = templates.ExecuteTemplate(w, "results.html", data)
    if err != nil {
        http.Error(w, "Failed to render template", http.StatusInternalServerError)
        return
    }
}