package http

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

	"github.com/debridmediamanager.com/zurg/internal/config"
	"github.com/debridmediamanager.com/zurg/internal/torrent"
	"github.com/debridmediamanager.com/zurg/pkg/logutil"
	"github.com/hashicorp/golang-lru/v2/expirable"
)

func HandleDirectoryListing(w http.ResponseWriter, r *http.Request, t *torrent.TorrentManager, c config.ConfigInterface, cache *expirable.LRU[string, string]) {
	log := logutil.NewLogger().Named("http")

	requestPath := path.Clean(r.URL.Path)

	if data, exists := cache.Get(requestPath); exists {
		w.Header().Set("Content-Type", "text/html; charset=\"utf-8\"")
		w.WriteHeader(http.StatusOK)
		fmt.Fprint(w, data)
		return
	}

	var output *string
	var err error

	filteredSegments := removeEmptySegments(strings.Split(requestPath, "/"))
	switch {
	case len(filteredSegments) == 1:
		output, err = handleRoot(w, r, c)
	case len(filteredSegments) == 2:
		output, err = handleListOfTorrents(requestPath, w, r, t, c)
	case len(filteredSegments) == 3:
		output, err = handleSingleTorrent(requestPath, w, r, t)
	default:
		log.Errorf("Request %s %s not found", r.Method, requestPath)
		http.Error(w, "Not Found", http.StatusNotFound)
		return
	}

	if err != nil {
		log.Errorf("Error processing request: %v", err)
		http.Error(w, "Server error", http.StatusInternalServerError)
		return
	}

	if output != nil {
		cache.Add(requestPath, *output)

		w.Header().Set("Content-Type", "text/html; charset=\"utf-8\"")
		w.WriteHeader(http.StatusOK)
		fmt.Fprint(w, *output)
	}
}

func handleRoot(w http.ResponseWriter, r *http.Request, c config.ConfigInterface) (*string, error) {
	htmlDoc := "<ul>"

	for _, directory := range c.GetDirectories() {
		directoryPath := url.PathEscape(directory)
		htmlDoc += fmt.Sprintf("<li><a href=\"/http/%s/\">%s</a></li>", directoryPath, directory)
	}

	return &htmlDoc, nil
}

func handleListOfTorrents(requestPath string, w http.ResponseWriter, r *http.Request, t *torrent.TorrentManager, c config.ConfigInterface) (*string, error) {
	basePath := path.Base(requestPath)

	for _, directory := range c.GetDirectories() {
		if basePath == directory {
			torrents := t.GetByDirectory(basePath)
			resp, err := createMultiTorrentResponse(requestPath, torrents)
			if err != nil {
				return nil, fmt.Errorf("cannot read directory (%s): %w", basePath, err)
			}
			return &resp, nil
		}
	}

	return nil, fmt.Errorf("cannot find directory when generating list: %s", requestPath)
}

func handleSingleTorrent(requestPath string, w http.ResponseWriter, r *http.Request, t *torrent.TorrentManager) (*string, error) {
	fullDir := path.Dir(requestPath)
	directory := path.Base(fullDir)
	torrentName := path.Base(requestPath)

	sameNameTorrents := t.FindAllTorrentsWithName(directory, torrentName)
	if len(sameNameTorrents) == 0 {
		return nil, fmt.Errorf("cannot find directory when generating single torrent: %s", requestPath)
	}

	resp, err := createSingleTorrentResponse(requestPath, sameNameTorrents)
	if err != nil {
		return nil, fmt.Errorf("cannot read directory (%s): %w", requestPath, err)
	}
	return &resp, nil
}