package main

import (
	"encoding/json"
	"fmt"
	"html/template"
	"log"
	"net/http"
	"net/url"
	"regexp"
	"sort"
	"strconv"
	"strings"
	"time"
)

type Settings struct {
	UxLang string
	Safe   string
}

type TorrentSite interface {
	Name() string
	Search(query string, category string) ([]TorrentResult, error)
}

var (
	torrentGalaxy TorrentSite
	nyaa          TorrentSite
	thePirateBay  TorrentSite
	rutor         TorrentSite
)

var fileResultsChan = make(chan []TorrentResult)

func initializeTorrentSites() {
	torrentGalaxy = NewTorrentGalaxy()
	// nyaa = NewNyaa()
	thePirateBay = NewThePirateBay()
	// rutor = NewRutor()
}

func handleFileSearch(w http.ResponseWriter, query, safe, lang string, page int) {
	startTime := time.Now()

	cacheKey := CacheKey{Query: query, Page: page, Safe: safe == "true", Lang: lang, Type: "file"}
	combinedResults := getFileResultsFromCacheOrFetch(cacheKey, query, safe, lang, page)

	sort.Slice(combinedResults, func(i, j int) bool { return combinedResults[i].Seeders > combinedResults[j].Seeders })

	elapsedTime := time.Since(startTime)
	funcMap := template.FuncMap{
		"sub": subtract,
		"add": add,
	}
	tmpl, err := template.New("files.html").Funcs(funcMap).ParseFiles("templates/files.html")
	if err != nil {
		log.Printf("Failed to load template: %v", err)
		http.Error(w, "Failed to load template", http.StatusInternalServerError)
		return
	}

	data := struct {
		Results     []TorrentResult
		Query       string
		Fetched     string
		Category    string
		Sort        string
		HasPrevPage bool
		HasNextPage bool
		Page        int
		Settings    Settings
	}{
		Results:     combinedResults,
		Query:       query,
		Fetched:     fmt.Sprintf("%.2f", elapsedTime.Seconds()),
		Category:    "all",
		Sort:        "seed",
		HasPrevPage: page > 1,
		HasNextPage: len(combinedResults) > 0,
		Page:        page,
		Settings:    Settings{UxLang: lang, Safe: safe},
	}

	// Debugging: Print results before rendering template
	for _, result := range combinedResults {
		fmt.Printf("Title: %s, Magnet: %s\n", result.Title, result.Magnet)
	}

	if err := tmpl.Execute(w, data); err != nil {
		log.Printf("Failed to render template: %v", err)
		http.Error(w, "Failed to render template", http.StatusInternalServerError)
	}
}

func getFileResultsFromCacheOrFetch(cacheKey CacheKey, query, safe, lang string, page int) []TorrentResult {
	cacheChan := make(chan []SearchResult)
	var combinedResults []TorrentResult

	go func() {
		results, exists := resultsCache.Get(cacheKey)
		if exists {
			log.Println("Cache hit")
			cacheChan <- results
		} else {
			log.Println("Cache miss")
			cacheChan <- nil
		}
	}()

	select {
	case results := <-cacheChan:
		if results == nil {
			combinedResults = fetchFileResults(query, safe, lang, page)
			if len(combinedResults) > 0 {
				resultsCache.Set(cacheKey, convertToSearchResults(combinedResults))
			}
		} else {
			_, torrentResults, _ := convertToSpecificResults(results)
			combinedResults = torrentResults
		}
	case <-time.After(2 * time.Second):
		log.Println("Cache check timeout")
		combinedResults = fetchFileResults(query, safe, lang, page)
		if len(combinedResults) > 0 {
			resultsCache.Set(cacheKey, convertToSearchResults(combinedResults))
		}
	}

	return combinedResults
}

func fetchFileResults(query, safe, lang string, page int) []TorrentResult {
	sites := []TorrentSite{torrentGalaxy, nyaa, thePirateBay, rutor}
	results := []TorrentResult{}

	for _, site := range sites {
		if site == nil {
			continue
		}
		res, err := site.Search(query, "all")
		if err != nil {
			continue
		}
		for _, r := range res {
			r.Magnet = removeMagnetLink(r.Magnet) // Remove "magnet:", prehaps usless now?
			results = append(results, r)
		}
	}

	if len(results) == 0 {
		log.Printf("No file results found for query: %s, trying other nodes", query)
		results = tryOtherNodesForFileSearch(query, safe, lang, page)
	}

	return results
}

func tryOtherNodesForFileSearch(query, safe, lang string, page int) []TorrentResult {
	for _, nodeAddr := range peers {
		results, err := sendFileSearchRequestToNode(nodeAddr, query, safe, lang, page)
		if err != nil {
			log.Printf("Error contacting node %s: %v", nodeAddr, err)
			continue
		}
		if len(results) > 0 {
			return results
		}
	}
	return nil
}

func sendFileSearchRequestToNode(nodeAddr, query, safe, lang string, page int) ([]TorrentResult, error) {
	searchParams := struct {
		Query        string `json:"query"`
		Safe         string `json:"safe"`
		Lang         string `json:"lang"`
		Page         int    `json:"page"`
		ResponseAddr string `json:"responseAddr"`
	}{
		Query:        query,
		Safe:         safe,
		Lang:         lang,
		Page:         page,
		ResponseAddr: fmt.Sprintf("http://localhost:%d/node", config.Port),
	}

	msgBytes, err := json.Marshal(searchParams)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal search parameters: %v", err)
	}

	msg := Message{
		ID:      hostID,
		Type:    "search-file",
		Content: string(msgBytes),
	}

	err = sendMessage(nodeAddr, msg)
	if err != nil {
		return nil, fmt.Errorf("failed to send search request to node %s: %v", nodeAddr, err)
	}

	// Wait for results
	select {
	case res := <-fileResultsChan:
		return res, nil
	case <-time.After(20 * time.Second):
		return nil, fmt.Errorf("timeout waiting for results from node %s", nodeAddr)
	}
}

func handleFileResultsMessage(msg Message) {
	var results []TorrentResult
	err := json.Unmarshal([]byte(msg.Content), &results)
	if err != nil {
		log.Printf("Error unmarshalling file results: %v", err)
		return
	}

	log.Printf("Received file results: %+v", results)
	// Send results to fileResultsChan
	go func() {
		fileResultsChan <- results
	}()
}

func removeMagnetLink(magnet string) string {
	// Remove the magnet: prefix unconditionally
	return strings.TrimPrefix(magnet, "magnet:")
}

func subtract(a, b int) int {
	return a - b
}

func add(a, b int) int {
	return a + b
}

func parseInt(s string) int {
	i, err := strconv.Atoi(s)
	if err != nil {
		return 0
	}
	return i
}

func parseSize(sizeStr string) int64 {
	sizeStr = strings.TrimSpace(sizeStr)
	if sizeStr == "" {
		return 0
	}

	// Use regex to extract numeric value and unit separately
	re := regexp.MustCompile(`(?i)([\d.]+)\s*([KMGT]?B)`)
	matches := re.FindStringSubmatch(sizeStr)
	if len(matches) < 3 {
		log.Printf("Error parsing size: invalid format %s", sizeStr)
		return 0
	}

	sizeStr = matches[1]
	unit := strings.ToUpper(matches[2])

	var multiplier int64 = 1
	switch unit {
	case "KB":
		multiplier = 1024
	case "MB":
		multiplier = 1024 * 1024
	case "GB":
		multiplier = 1024 * 1024 * 1024
	case "TB":
		multiplier = 1024 * 1024 * 1024 * 1024
	default:
		log.Printf("Unknown unit: %s", unit)
		return 0
	}

	size, err := strconv.ParseFloat(sizeStr, 64)
	if err != nil {
		log.Printf("Error parsing size: %v", err)
		return 0
	}
	return int64(size * float64(multiplier))
}

// apparently this is needed so it can announce that magnet link is being used and people start seeding it, but I dont like the fact that I add trackers purposefully
func applyTrackers(magnetLink string) string {
	if magnetLink == "" {
		return ""
	}
	trackers := []string{
		"udp://tracker.openbittorrent.com:80/announce",
		"udp://tracker.opentrackr.org:1337/announce",
		"udp://tracker.coppersurfer.tk:6969/announce",
		"udp://tracker.leechers-paradise.org:6969/announce",
	}
	for _, tracker := range trackers {
		magnetLink += "&tr=" + url.QueryEscape(tracker)
	}
	return magnetLink
}

func formatSize(size int64) string {
	if size >= 1024*1024*1024*1024 {
		return fmt.Sprintf("%.2f TB", float64(size)/(1024*1024*1024*1024))
	} else if size >= 1024*1024*1024 {
		return fmt.Sprintf("%.2f GB", float64(size)/(1024*1024*1024))
	} else if size >= 1024*1024 {
		return fmt.Sprintf("%.2f MB", float64(size)/(1024*1024))
	} else if size >= 1024 {
		return fmt.Sprintf("%.2f KB", float64(size)/1024)
	}
	return fmt.Sprintf("%d B", size)
}

func sanitizeFileName(name string) string {
	// Replace spaces with dashes
	sanitized := regexp.MustCompile(`\s+`).ReplaceAllString(name, "-")
	// Remove any characters that are not alphanumeric, dashes, or parentheses
	sanitized = regexp.MustCompile(`[^a-zA-Z0-9\-\(\)]`).ReplaceAllString(sanitized, "")
	return sanitized
}