1package main
  2
  3import (
  4	"bytes"
  5	"html/template"
  6	"io"
  7	"net/http"
  8	"net/url"
  9	"os"
 10	"regexp"
 11	"strconv"
 12	"time"
 13
 14	"github.com/BiRabittoh/fixyoutube-go/invidious"
 15	"github.com/gorilla/mux"
 16	"github.com/joho/godotenv"
 17	"github.com/sirupsen/logrus"
 18)
 19
 20const templatesDirectory = "templates/"
 21
 22var logger = logrus.New()
 23var indexTemplate = template.Must(template.ParseFiles(templatesDirectory + "index.html"))
 24var videoTemplate = template.Must(template.ParseFiles(templatesDirectory + "video.html"))
 25var userAgentRegex = regexp.MustCompile(`(?i)bot|facebook|embed|got|firefox\/92|firefox\/38|curl|wget|go-http|yahoo|generator|whatsapp|preview|link|proxy|vkshare|images|analyzer|index|crawl|spider|python|cfnetwork|node`)
 26var videoRegex = regexp.MustCompile(`(?i)^[a-z0-9_-]{11}$`)
 27
 28var apiKey string
 29
 30func indexHandler(w http.ResponseWriter, r *http.Request) {
 31	buf := &bytes.Buffer{}
 32	err := indexTemplate.Execute(buf, nil)
 33	if err != nil {
 34		logger.Error("Failed to fill index template.")
 35		http.Error(w, err.Error(), http.StatusInternalServerError)
 36		return
 37	}
 38
 39	buf.WriteTo(w)
 40}
 41
 42func clearHandler(w http.ResponseWriter, r *http.Request) {
 43	if r.Method != http.MethodPost {
 44		http.Redirect(w, r, "/", http.StatusMovedPermanently)
 45		return
 46	}
 47
 48	err := r.ParseForm()
 49	if err != nil {
 50		logger.Error("Failed to parse form in /clear.")
 51		http.Error(w, err.Error(), http.StatusInternalServerError)
 52		return
 53	}
 54
 55	providedKey := r.PostForm.Get("apiKey")
 56	if providedKey != apiKey {
 57		logger.Debug("Wrong API key: ", providedKey)
 58		http.Error(w, "Wrong or missing API key.", http.StatusForbidden)
 59		return
 60	}
 61
 62	invidious.ClearDB()
 63	logger.Info("Cache cleared.")
 64	http.Error(w, "Done.", http.StatusOK)
 65}
 66
 67func videoHandler(videoId string, invidiousClient *invidious.Client, w http.ResponseWriter, r *http.Request) {
 68	userAgent := r.UserAgent()
 69	res := userAgentRegex.MatchString(userAgent)
 70	if !res {
 71		logger.Debug("Regex did not match. Redirecting. UA:", userAgent)
 72		url := "https://www.youtube.com/watch?v=" + videoId
 73		http.Redirect(w, r, url, http.StatusMovedPermanently)
 74		return
 75	}
 76
 77	if !videoRegex.MatchString(videoId) {
 78		logger.Info("Invalid video ID: ", videoId)
 79		http.Error(w, "Invalid video ID.", http.StatusBadRequest)
 80		return
 81	}
 82
 83	video, err := invidiousClient.GetVideo(videoId, true)
 84	if err != nil {
 85		logger.Info("Wrong video ID: ", videoId)
 86		http.Error(w, "Wrong video ID.", http.StatusNotFound)
 87		return
 88	}
 89
 90	buf := &bytes.Buffer{}
 91	err = videoTemplate.Execute(buf, video)
 92	if err != nil {
 93		logger.Error("Failed to fill video template.")
 94		http.Error(w, err.Error(), http.StatusInternalServerError)
 95		return
 96	}
 97	buf.WriteTo(w)
 98}
 99
100func watchHandler(invidiousClient *invidious.Client) http.HandlerFunc {
101	return func(w http.ResponseWriter, r *http.Request) {
102		u, err := url.Parse(r.URL.String())
103		if err != nil {
104			logger.Error("Failed to parse URL: ", r.URL.String())
105			http.Error(w, err.Error(), http.StatusInternalServerError)
106			return
107		}
108		q := u.Query()
109		videoId := q.Get("v")
110		videoHandler(videoId, invidiousClient, w, r)
111	}
112}
113
114func shortHandler(invidiousClient *invidious.Client) http.HandlerFunc {
115	return func(w http.ResponseWriter, r *http.Request) {
116		vars := mux.Vars(r)
117		videoId := vars["videoId"]
118		videoHandler(videoId, invidiousClient, w, r)
119	}
120}
121
122func proxyHandler(invidiousClient *invidious.Client) http.HandlerFunc {
123	return func(w http.ResponseWriter, r *http.Request) {
124		vars := mux.Vars(r)
125		videoId := vars["videoId"]
126
127		video, err := invidious.GetVideoDB(videoId)
128		if err != nil {
129			logger.Warn("Cannot proxy a video that is not cached: https://youtu.be/", videoId)
130			http.Error(w, "Something went wrong.", http.StatusBadRequest)
131			return
132		}
133
134		fmtAmount := len(video.Formats)
135
136		var httpStatus = http.StatusNotFound
137
138		for i := fmtAmount - 1; i >= 0; i-- {
139			url := video.Formats[i].Url
140			b, l, httpStatus := invidiousClient.ProxyVideo(url)
141			switch httpStatus {
142			case http.StatusOK:
143				h := w.Header()
144				h.Set("Status", "200")
145				h.Set("Content-Type", "video/mp4")
146				h.Set("Content-Length", strconv.FormatInt(l, 10))
147				io.Copy(w, b)
148				return
149			case http.StatusBadRequest:
150				continue
151			default:
152				i = -1
153			}
154		}
155		logger.Error("proxyHandler() failed. Code: ", httpStatus)
156		http.Error(w, "Something went wrong.", httpStatus)
157	}
158}
159
160func main() {
161	//logger.SetLevel(logrus.DebugLevel)
162	err := godotenv.Load()
163	if err != nil {
164		logger.Info("No .env file provided.")
165	}
166
167	port := os.Getenv("PORT")
168	if port == "" {
169		port = "3000"
170	}
171
172	apiKey = os.Getenv("API_KEY")
173	if apiKey == "" {
174		apiKey = "itsme"
175	}
176
177	myClient := &http.Client{Timeout: 10 * time.Second}
178	videoapi := invidious.NewClient(myClient)
179
180	r := mux.NewRouter()
181	r.HandleFunc("/", indexHandler)
182	r.HandleFunc("/clear", clearHandler)
183	r.HandleFunc("/watch", watchHandler(videoapi))
184	r.HandleFunc("/proxy/{videoId}", proxyHandler(videoapi))
185	r.HandleFunc("/{videoId}", shortHandler(videoapi))
186	/*
187		// native go implementation
188		r := http.NewServeMux()
189		r.HandleFunc("/watch", watchHandler(videoapi))
190		r.HandleFunc("/{videoId}/", shortHandler(videoapi))
191		r.HandleFunc("/", indexHandler)
192	*/
193	logger.Info("Serving on port ", port)
194	http.ListenAndServe(":"+port, r)
195}