Refactor to downloader

internal/universal/downloader.go

@@ -0,0 +1,199 @@
+package universal
+
+import (
+	"io"
+	"net/http"
+	"path/filepath"
+	"strings"
+
+	"github.com/debridmediamanager/zurg/internal/config"
+	intTor "github.com/debridmediamanager/zurg/internal/torrent"
+	zurghttp "github.com/debridmediamanager/zurg/pkg/http"
+	"github.com/debridmediamanager/zurg/pkg/logutil"
+	"github.com/debridmediamanager/zurg/pkg/realdebrid"
+)
+
+type Downloader struct {
+	client *zurghttp.HTTPClient
+}
+
+func NewDownloader(client *zurghttp.HTTPClient) *Downloader {
+	return &Downloader{client: client}
+}
+
+// DownloadFile handles a GET request for files in torrents
+func (dl *Downloader) DownloadFile(directory, torrentName, fileName string, resp http.ResponseWriter, req *http.Request, torMgr *intTor.TorrentManager, cfg config.ConfigInterface, log *logutil.Logger) {
+	torrents, ok := torMgr.DirectoryMap.Get(directory)
+	if !ok {
+		log.Warnf("Cannot find directory %s", directory)
+		http.Error(resp, "File not found", http.StatusNotFound)
+		return
+	}
+	torrent, ok := torrents.Get(torrentName)
+	if !ok {
+		log.Warnf("Cannot find torrent %sfrom path %s", torrentName, req.URL.Path)
+		http.Error(resp, "File not found", http.StatusNotFound)
+		return
+	}
+
+	file, ok := torrent.SelectedFiles.Get(fileName)
+	if !ok {
+		log.Warnf("Cannot find file %s from path %s", fileName, req.URL.Path)
+		http.Error(resp, "File not found", http.StatusNotFound)
+		return
+	}
+
+	if !strings.HasPrefix(file.Link, "http") {
+		// This is a dead file, serve an alternate file
+		log.Warnf("File %s is not available", fileName)
+		http.Error(resp, "File is not available", http.StatusNotFound)
+		return
+	}
+	link := file.Link
+
+	log.Debugf("Opening file %s from torrent %s (%s)", fileName, torrentName, link)
+	unrestrict := torMgr.UnrestrictUntilOk(link)
+	if unrestrict == nil {
+		log.Warnf("File %s cannot be unrestricted (link=%s)", fileName, link)
+		if cfg.EnableRepair() {
+			file.Link = "repair"
+			torMgr.Repair(torrent)
+		} else {
+			log.Infof("Repair is disabled, skipping repair for unavailable file %s (link=%s)", fileName, link)
+		}
+		http.Error(resp, "File is not available", http.StatusNotFound)
+		return
+	} else {
+		if unrestrict.Filename != fileName {
+			// this is possible if there's only 1 streamable file in the torrent
+			// and then suddenly it's a rar file
+			actualExt := filepath.Ext(unrestrict.Filename)
+			expectedExt := filepath.Ext(fileName)
+			if actualExt != expectedExt && unrestrict.Streamable != 1 {
+				log.Warnf("File was changed and is not streamable: %s and %s (link=%s)", fileName, unrestrict.Filename, unrestrict.Link)
+				http.Error(resp, "File is not available", http.StatusNotFound)
+				return
+			} else {
+				log.Warnf("Filename mismatch: %s and %s", fileName, unrestrict.Filename)
+			}
+		}
+		if cfg.ShouldServeFromRclone() {
+			if cfg.ShouldVerifyDownloadLink() {
+				if !torMgr.Api.CanFetchFirstByte(unrestrict.Download) {
+					log.Warnf("File %s is not available", fileName)
+					http.Error(resp, "File is not available", http.StatusNotFound)
+					return
+				}
+			}
+			redirect(resp, req, unrestrict.Download, cfg)
+		} else {
+			dl.streamFileToResponse(torrent, file, unrestrict, resp, req, torMgr, cfg, log)
+		}
+		return
+	}
+}
+
+// DownloadLink handles a GET request for downloads
+func (dl *Downloader) DownloadLink(fileName, link string, resp http.ResponseWriter, req *http.Request, torMgr *intTor.TorrentManager, cfg config.ConfigInterface, log *logutil.Logger) {
+	if !strings.HasPrefix(link, "http") {
+		// This is a dead file, serve an alternate file
+		log.Warnf("File %s is not available", fileName)
+		http.Error(resp, "File is not available", http.StatusNotFound)
+		return
+	}
+
+	log.Debugf("Opening download %s", fileName)
+	unrestrict := torMgr.UnrestrictUntilOk(link)
+	if unrestrict == nil {
+		log.Warnf("File %s cannot be unrestricted (link=%s)", fileName, link)
+		http.Error(resp, "File is not available", http.StatusNotFound)
+		return
+	} else {
+		if unrestrict.Filename != fileName {
+			// this is possible if there's only 1 streamable file in the torrent
+			// and then suddenly it's a rar file
+			actualExt := filepath.Ext(unrestrict.Filename)
+			expectedExt := filepath.Ext(fileName)
+			if actualExt != expectedExt && unrestrict.Streamable != 1 {
+				log.Warnf("File was changed and is not streamable: %s and %s (link=%s)", fileName, unrestrict.Filename, unrestrict.Link)
+				http.Error(resp, "File is not available", http.StatusNotFound)
+				return
+			} else {
+				log.Warnf("Filename mismatch: %s and %s", fileName, unrestrict.Filename)
+			}
+		}
+		if cfg.ShouldServeFromRclone() {
+			if cfg.ShouldVerifyDownloadLink() {
+				if !torMgr.Api.CanFetchFirstByte(unrestrict.Download) {
+					log.Warnf("File %s is not available", fileName)
+					http.Error(resp, "File is not available", http.StatusNotFound)
+					return
+				}
+			}
+			redirect(resp, req, unrestrict.Download, cfg)
+		} else {
+			dl.streamFileToResponse(nil, nil, unrestrict, resp, req, torMgr, cfg, log)
+		}
+		return
+	}
+}
+
+func (dl *Downloader) streamFileToResponse(torrent *intTor.Torrent, file *intTor.File, unrestrict *realdebrid.Download, resp http.ResponseWriter, req *http.Request, torMgr *intTor.TorrentManager, cfg config.ConfigInterface, log *logutil.Logger) {
+	// Create a new request for the file download.
+	dlReq, err := http.NewRequest(http.MethodGet, unrestrict.Download, nil)
+	if err != nil {
+		if file != nil {
+			log.Errorf("Error creating new request for file %s: %v", file.Path, err)
+		}
+		http.Error(resp, "File is not available", http.StatusNotFound)
+		return
+	}
+
+	// copy range header if it exists
+	if req.Header.Get("Range") != "" {
+		dlReq.Header.Add("Range", req.Header.Get("Range"))
+	}
+
+	download, err := dl.client.Do(dlReq)
+	if err != nil {
+		if file != nil && unrestrict.Streamable == 1 {
+			log.Warnf("Cannot download file %s: %v", file.Path, err)
+			if cfg.EnableRepair() && torrent != nil {
+				file.Link = "repair"
+				torMgr.Repair(torrent)
+			} else {
+				log.Infof("Repair is disabled, skipping repair for unavailable file %s (link=%s)", file.Path, file.Link)
+			}
+		}
+		http.Error(resp, "File is not available", http.StatusNotFound)
+		return
+	}
+	defer download.Body.Close()
+
+	if download.StatusCode != http.StatusOK && download.StatusCode != http.StatusPartialContent {
+		if file != nil && unrestrict.Streamable == 1 {
+			log.Warnf("Received a %s status code for file %s", download.Status, file.Path)
+			if cfg.EnableRepair() && torrent != nil {
+				file.Link = "repair"
+				torMgr.Repair(torrent)
+			} else {
+				log.Infof("Repair is disabled, skipping repair for unavailable file %s (link=%s)", file.Path, file.Link)
+			}
+		}
+		http.Error(resp, "File is not available", http.StatusNotFound)
+		return
+	}
+
+	for k, vv := range download.Header {
+		for _, v := range vv {
+			resp.Header().Add(k, v)
+		}
+	}
+
+	buf := make([]byte, cfg.GetNetworkBufferSize())
+	io.CopyBuffer(resp, download.Body, buf)
+}
+
+func redirect(resp http.ResponseWriter, req *http.Request, url string, cfg config.ConfigInterface) {
+	http.Redirect(resp, req, url, http.StatusFound)
+}