import yt_dlp
import os
import shutil

def validate_youtube_url(url):
    if 'youtube.com/watch?v=' not in url and 'music.youtube.com/watch?v=' not in url:
        return False, None, None
    
    try:
        vid = url.split('v=')[1].split('&')[0].split('#')[0]
        if len(vid) != 11:
            return False, None, None
    except:
        return False, None, None    
    provider = 'YTM' if 'music.youtube.com' in url else 'YT'
    yt_opts = {'quiet': True, 'ignoreerrors': True}
    with yt_dlp.YoutubeDL(yt_opts) as ydl:
        info = ydl.extract_info(url, download=False)
    return bool(info), vid, provider

def process_musiclist():
    shutil.copyfile('musiclist.txt', 'musiclist_backup.txt')
    temp_lines = []
    with open('musiclist.txt', 'r') as f:
        for line_num, line in enumerate(f, 1):
            line = line.strip()
            if not line:
                temp_lines.append(line)
                continue
            try:
                musicname, old_vid, provider = line.split('---')
                musicname = musicname.strip()
                old_vid = old_vid.strip()
                provider = provider.strip()
            except:
                print(f"⚠️ Invalid line format (line {line_num}): {line}")
                temp_lines.append(line)
                continue
            
            base_url = f'https://{"music." if provider=="YTM" else ""}youtube.com/watch?v={old_vid}'
            is_valid, _, _ = validate_youtube_url(base_url)
            
            if is_valid:
                temp_lines.append(line)
                continue

            print(f"\n🔴 Invalid: {musicname}")
            print(f"Current URL: {base_url}")
            while True:
                new_url = input("Enter new YouTube URL (cancel with 'x'): ").strip()
                if new_url.lower() == 'x':
                    temp_lines.append(line)
                    print("Cancelled, original entry preserved")
                    break
                
                is_valid, vid, detected_provider = validate_youtube_url(new_url)
                if is_valid:
                    new_line = f"{musicname} --- {vid} --- {detected_provider}"
                    temp_lines.append(new_line)
                    print(f"Updated: {new_line}")
                    break
                print("❌ Invalid URL or video! Try again.")

    print("\n" + "═"*50)
    print(f"Total {len(temp_lines)} entries processed")
    confirmation = input("Save changes? (Y/N): ").strip().lower()
    
    if confirmation == 'y':
        with open('musiclist.txt', 'w') as f:
            f.write('\n'.join(temp_lines))
        print("✔️ Music list updated successfully!")
        print("Backup of original file: musiclist_backup.txt")
    else:
        print("❌ Changes discarded, file unchanged")

if __name__ == "__main__":
    print("A backup of your original file will be created automatically\n")
    if not os.path.exists('musiclist.txt'):
        print("Error: musiclist.txt not found!")
        exit()
    process_musiclist()