package http

import (
	"time"
	"mime/multipart"
	"net/textproto"
	"strconv"
	"net/http"
	"strings"
	"os"
	"html/template"
)

func NewServer(port string) (error) {
	server := http.NewServeMux()
	server_setup(server)
	if err := http.ListenAndServe(":" + port, server); err != nil {
		return err
	}
	return nil
}

func server_setup(server *http.ServeMux) {
	server.HandleFunc("/live/", serve_main_page) // main page with the video element, separate for each streamkey
	server.HandleFunc("/list/", serve_live_playlist) // uri returns the playlist file for the given stream key
	server.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.Dir("static/")))) // returns static files (eventually for the local hls player implementation)
	server.HandleFunc("/vid/", serve_vid_segment) // serves the appropriate static video segment
	server.HandleFunc("/img/", serve_img_loop)
}

func serve_vid_segment(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Cache-Control", "no-cache")
	base_dir, _ := os.UserHomeDir()
	tmp := strings.Split(strings.TrimPrefix(r.URL.Path, "/vid/"), "/")
	stream_key := tmp[0]
	segment_file := tmp[1]
	http.ServeFile(w, r, base_dir + "/live/" + stream_key + "/" + segment_file)
}

func serve_live_playlist(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Cache-Control", "no-cache")
	stream_id := strings.TrimPrefix(r.URL.Path, "/list/")
	base_dir, _ := os.UserHomeDir()
	stream_playlist_path := base_dir + "/live/" + stream_id + "/stream.m3u8"
	if _, err := os.Stat(stream_playlist_path); err != nil {
		http.NotFound(w, r)
	} else {
		http.ServeFile(w, r, stream_playlist_path)
	}
}

func serve_main_page(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Access-Control-Allow-Origin", "*") // bad jank for hls.js loading from cdn. cross-site js bad.
	page := template.Must(template.ParseFiles("static/index.html"))
	stream_user := strings.TrimPrefix(r.URL.Path, "/live/")
	page.Execute(w, stream_user) // literally only to define the uri for playlist loading, should be a script but eh
}

func serve_img_loop(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Cache-Control", "no-cache")
	stream_id := strings.TrimPrefix(r.URL.Path, "/img/")
	base_dir, _ := os.UserHomeDir()
	img_path := base_dir + "/live/" + stream_id + "/out.jpg"

	writer := multipart.NewWriter(w)
	w.Header().Set("Content-Type", "multipart/x-mixed-replace; boundary=" + writer.Boundary())
	for {
		img, err := os.ReadFile(img_path)
		if err != nil {
			continue
		}
		part, err := writer.CreatePart(textproto.MIMEHeader{"Content-Type": {"image/jpeg"}, "Content-Length": {strconv.Itoa(len(img))}})
		if err != nil {
			break
		}
		part.Write(img)
		time.Sleep(33 * time.Millisecond)
	}
	writer.Close()
	
}