reels-app/scripts/acr_recognize.py

"""
acr_recognize.py — Audio recognition prek ACRCloud Audio Fingerprinting API.

Uporabi native binary za fingerprinting (3KB sample namesto cel audio).
Vrne (artist, title) ali (None, None) če pesem ni prepoznana.

Credentials se preberejo iz env vars (ACR_ACCESS_KEY, ACR_SECRET_KEY, ACR_HOST).
"""
import os
import sys
import json
import hmac
import base64
import time
import subprocess
import tempfile
import urllib.request
import urllib.parse
import uuid


def _sign(string_to_sign, secret):
    h = hmac.new(secret.encode('ascii'), string_to_sign.encode('ascii'), digestmod='sha1')
    return base64.b64encode(h.digest()).decode('ascii')


def _build_multipart(fields, files):
    """Sestavi multipart/form-data body."""
    boundary = uuid.uuid4().hex
    parts = []
    for k, v in fields.items():
        parts.append(f"--{boundary}\r\nContent-Disposition: form-data; name=\"{k}\"\r\n\r\n{v}\r\n".encode())
    for k, (fname, content, ctype) in files.items():
        parts.append(
            f"--{boundary}\r\nContent-Disposition: form-data; name=\"{k}\"; filename=\"{fname}\"\r\n"
            f"Content-Type: {ctype}\r\n\r\n".encode() + content + b"\r\n"
        )
    parts.append(f"--{boundary}--\r\n".encode())
    body = b"".join(parts)
    return body, boundary


def recognize_audio_file(audio_path, timeout=30):
    """Pošlji audio file (ali fingerprint) ACRCloud-u in vrni raw response.
    
    audio_path: pot do MP3/WAV/M4A datoteke.
    Vrne dict z odgovorom ali None ob napaki.
    """
    host = os.environ.get("ACR_HOST", "identify-eu-west-1.acrcloud.com")
    access_key = os.environ.get("ACR_ACCESS_KEY")
    secret_key = os.environ.get("ACR_SECRET_KEY")
    
    if not access_key or not secret_key:
        print("⚠️ ACR_ACCESS_KEY/SECRET_KEY nista nastavljena", file=sys.stderr)
        return None
    
    if not os.path.exists(audio_path):
        print(f"⚠️ Audio file ne obstaja: {audio_path}", file=sys.stderr)
        return None
    
    # Probaj native binary za fingerprint (manjši payload)
    fingerprint = None
    try:
        from acrcloud import acrcloud_extr_tool as acr
        fingerprint = acr.create_fingerprint_by_file(audio_path, 0, 30, 0)
    except (ImportError, Exception) as e:
        print(f"   ℹ️ Fingerprint binary ni na voljo ({e}), uporabljam audio direktno", file=sys.stderr)
    
    timestamp = str(int(time.time()))
    http_method = "POST"
    http_uri = "/v1/identify"
    signature_version = "1"
    
    if fingerprint:
        data_type = "fingerprint"
        sample_data = fingerprint
        sample_name = "sample.fp"
        sample_ctype = "application/octet-stream"
    else:
        data_type = "audio"
        with open(audio_path, "rb") as f:
            sample_data = f.read()
        sample_name = "sample.mp3"
        sample_ctype = "audio/mpeg"
    
    string_to_sign = f"{http_method}\n{http_uri}\n{access_key}\n{data_type}\n{signature_version}\n{timestamp}"
    signature = _sign(string_to_sign, secret_key)
    
    fields = {
        "access_key": access_key,
        "sample_bytes": str(len(sample_data)),
        "timestamp": timestamp,
        "signature": signature,
        "data_type": data_type,
        "signature_version": signature_version,
    }
    files = {"sample": (sample_name, sample_data, sample_ctype)}
    body, boundary = _build_multipart(fields, files)
    
    url = f"https://{host}/v1/identify"
    req = urllib.request.Request(
        url, data=body,
        headers={"Content-Type": f"multipart/form-data; boundary={boundary}"},
        method="POST",
    )
    try:
        with urllib.request.urlopen(req, timeout=timeout) as resp:
            return json.loads(resp.read().decode())
    except Exception as e:
        print(f"⚠️ ACR API napaka: {e}", file=sys.stderr)
        return None


def extract_short_audio(video_path, duration=20, start_offset=15):
    """Izloči kratek audio iz videa za ACR fingerprint.
    
    Začnemo 15s v video (preskoči intro) in vzamemo 20s.
    Za MXF/multichannel: izberemo prvi audio stream, downmix v stereo.
    Vrne pot do tmp MP3 ali None.
    """
    tmp_fd, tmp_path = tempfile.mkstemp(suffix=".mp3")
    os.close(tmp_fd)
    cmd = [
        "ffmpeg", "-i", video_path,
        "-ss", str(start_offset),
        "-t", str(duration),
        "-map", "0:a:0",  # samo prvi audio stream (varno za MXF z več streami)
        "-vn",
        "-ac", "2",   # downmix v stereo (če multichannel)
        "-ar", "44100",
        "-b:a", "128k",
        "-f", "mp3", tmp_path,
        "-y", "-loglevel", "error"
    ]
    proc = subprocess.run(cmd, capture_output=True, text=True)
    if proc.returncode != 0:
        os.unlink(tmp_path)
        print(f"⚠️ ffmpeg napaka: {proc.stderr[:200]}", file=sys.stderr)
        return None
    return tmp_path


def recognize_video(video_path):
    """Glavni vstop: prepoznaj pesem v videu, vrni (artist, title) ali (None, None).
    
    Probavamo 2 točki v videu (15s in 60s) za večjo robustnost — če ni intro/instrumental.
    """
    if not os.environ.get("ACR_ACCESS_KEY"):
        return (None, None)
    
    for start_offset in [15, 60]:
        audio = extract_short_audio(video_path, duration=20, start_offset=start_offset)
        if not audio:
            continue
        try:
            result = recognize_audio_file(audio)
        finally:
            try:
                os.unlink(audio)
            except OSError:
                pass
        
        if not result:
            continue
        
        status = result.get("status", {}).get("code")
        if status != 0:
            # 1001 = no result, drugi = napaka
            msg = result.get("status", {}).get("msg", "")
            print(f"   ℹ️ ACR @{start_offset}s: status={status} ({msg})", file=sys.stderr)
            continue
        
        # Uspeh — vzemi prvi music match
        music = result.get("metadata", {}).get("music", [])
        if not music:
            continue
        
        first = music[0]
        title = first.get("title", "").strip()
        artists = first.get("artists", [])
        artist = artists[0].get("name", "").strip() if artists else ""
        
        if artist and title:
            print(f"   ✅ ACR @{start_offset}s prepoznal: {artist} - {title}", file=sys.stderr)
            return (artist, title)
    
    print("   ⚠️ ACR pesem ni prepoznana", file=sys.stderr)
    return (None, None)


if __name__ == "__main__":
    if len(sys.argv) != 2:
        print("Uporaba: python3 acr_recognize.py <video.mp4>")
        sys.exit(1)
    
    artist, title = recognize_video(sys.argv[1])
    if artist and title:
        print(json.dumps({"artist": artist, "title": title}, ensure_ascii=False))
        sys.exit(0)
    else:
        print(json.dumps({"artist": None, "title": None}))
        sys.exit(1)