package dav

import (
	"encoding/xml"
	"fmt"
	"log"
	"net/http"
	"path"
	"strings"

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

func HandlePropfindRequest(w http.ResponseWriter, r *http.Request, t *torrent.TorrentManager, c config.ConfigInterface, cache *expirable.LRU[string, string]) {
	requestPath := path.Clean(r.URL.Path)
	requestPath = strings.Trim(requestPath, "/")

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

	var output []byte
	var err error

	filteredSegments := strings.Split(requestPath, "/")

	switch {
	case len(filteredSegments) == 1 && filteredSegments[0] == "":
		output, err = handleRoot(w, r, c)
	case len(filteredSegments) == 1:
		output, err = handleListOfTorrents(requestPath, w, r, t, c)
	case len(filteredSegments) == 2:
		output, err = handleSingleTorrent(requestPath, w, r, t)
	default:
		writeHTTPError(w, "Not Found", http.StatusNotFound)
		return
	}

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

	if output != nil {
		respBody := fmt.Sprintf("<?xml version=\"1.0\" encoding=\"utf-8\"?>\n%s\n", output)
		cache.Add(requestPath, respBody)

		w.Header().Set("Content-Type", "text/xml; charset=\"utf-8\"")
		w.WriteHeader(http.StatusMultiStatus)
		fmt.Fprint(w, respBody)
	}
}

func handleRoot(w http.ResponseWriter, r *http.Request, c config.ConfigInterface) ([]byte, error) {
	var responses []dav.Response
	responses = append(responses, dav.Directory("/"))
	for _, directory := range c.GetDirectories() {
		responses = append(responses, dav.Directory("/"+directory))
	}
	rootResponse := dav.MultiStatus{
		XMLNS:    "DAV:",
		Response: responses,
	}
	return xml.Marshal(rootResponse)
}

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

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

	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) ([]byte, error) {
	directory := path.Dir(requestPath)
	torrentName := path.Base(requestPath)

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

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

func writeHTTPError(w http.ResponseWriter, errorMessage string, statusCode int) {
	log.Println(errorMessage)
	http.Error(w, errorMessage, statusCode)
}