#!/usr/bin/env python3
from http.server import SimpleHTTPRequestHandler, ThreadingHTTPServer
import os
import argparse
import sys

def parse_args():
    p = argparse.ArgumentParser(description="Semplice server HTTP per HLS con CORS")
    p.add_argument("root", nargs="?", default="hls_ts_test",
                   help="Directory da servire (default: hls_ts_test)")
    p.add_argument("-p", "--port", type=int, default=9999,
                   help="Porta su cui ascoltare (default: 9999)")
    return p.parse_args()

class HlsHandler(SimpleHTTPRequestHandler):
    extensions_map = {
        **SimpleHTTPRequestHandler.extensions_map,
        ".m3u8": "application/vnd.apple.mpegurl",
        ".ts": "video/mp2t",
    }

    # 🔥 Patch: disabilita 304 e gestisce Range correttamente
    def send_head(self):
        path = self.translate_path(self.path)

        if os.path.isdir(path):
            return self.list_directory(path)

        ctype = self.guess_type(path)
        try:
            f = open(path, "rb")
        except OSError:
            self.send_error(404, "File not found")
            return None

        fs = os.fstat(f.fileno())
        size = fs.st_size

        # Gestione Range (necessaria per Chromecast)
        range_header = self.headers.get("Range")
        if range_header:
            try:
                start = int(range_header.replace("bytes=", "").split("-")[0])
            except:
                start = 0

            self.send_response(206)
            self.send_header("Content-type", ctype)
            self.send_header("Content-Range", f"bytes {start}-{size-1}/{size}")
            self.send_header("Content-Length", str(size - start))
            self.end_headers()
            f.seek(start)
            return f

        # Risposta normale 200 OK (mai 304)
        self.send_response(200)
        self.send_header("Content-type", ctype)
        self.send_header("Content-Length", str(size))
        self.send_header("Last-Modified", self.date_time_string(fs.st_mtime))
        self.end_headers()
        return f

    def end_headers(self):
        # CORS e cache control
        self.send_header("Access-Control-Allow-Origin", "*")
        self.send_header("Access-Control-Expose-Headers",
                         "Content-Length, Content-Type, Accept-Ranges")
        self.send_header("Cache-Control", "no-cache")
        super().end_headers()

    def do_OPTIONS(self):
        self.send_response(204)
        self.send_header("Access-Control-Allow-Origin", "*")
        self.send_header("Access-Control-Allow-Methods", "GET, HEAD, OPTIONS")
        self.send_header("Access-Control-Allow-Headers", "Range")
        self.end_headers()

def main():
    args = parse_args()
    root = os.path.abspath(args.root)
    port = args.port

    if not os.path.isdir(root):
        print(f"Directory non trovata: {root}", file=sys.stderr)
        sys.exit(1)

    os.chdir(root)

    server = ThreadingHTTPServer(("0.0.0.0", port), HlsHandler)
    print(f"Serving {root} on http://0.0.0.0:{port}", flush=True)
    try:
        server.serve_forever()
    except KeyboardInterrupt:
        print("\nServer interrotto dall'utente")
    finally:
        server.server_close()

if __name__ == "__main__":
    main()