/**
 * Extracts a YouTube video ID from various URL formats.
 * @param url The YouTube URL.
 * @returns The video ID, or null if not found.
 */
const extractYouTubeVideoId = (url: string): string | null => {
  if (!url || typeof url !== 'string') return null;
  
  const regExp = /(?:youtube\.com\/(?:[^\/]+\/.+\/|(?:v|e(?:mbed)?)\/|.*[?&]v=|[^\/]+\/(?:live|shorts)\/)|youtu\.be\/)([^"&?\/\s]{11})/;
  const match = url.match(regExp);

  if (match && match[1]) {
    return match[1];
  }
  return null;
};

/**
 * Generates a YouTube embed URL with common parameters and API support.
 * @param url The original YouTube URL.
 * @returns The embed URL string, or null if the video ID cannot be extracted or URL is invalid.
 */
export const getYouTubeEmbedUrl = (url: string): string | null => {
  const videoId = extractYouTubeVideoId(url);
  if (!videoId) {
    return null;
  }
  // Common parameters + enablejsapi for API control + origin for security
  // mute=1 is important for allowing autoplay and programmatic unmuting.
  // The origin parameter MUST match the domain where the iframe is hosted.
  const origin = typeof window !== 'undefined' ? window.location.origin : '';
  const params = `autoplay=1&mute=1&playsinline=1&controls=1&modestbranding=1&rel=0&fs=1&iv_load_policy=3&enablejsapi=1&origin=${encodeURIComponent(origin)}`;
  return `https://www.youtube.com/embed/${videoId}?${params}`;
};