VAST 4.x Compliance

const sdk = new AdgentSDK({
  container: document.getElementById('ad-container')!,
  vastUrl: 'https://example.com/vast.xml',
  maxWrapperDepth: 5  // Default value
});

// Wrapper tracking events are prepended to nested ad events
// This ensures all levels of the wrapper chain receive tracking pixels
const mergedTracking = [
  ...wrapperTrackingEvents,
  ...nestedAdTrackingEvents
];

selectBestMediaFile(
  mediaFiles: MediaFile[],
  targetBitrate = 2500
): MediaFile | null {
  // Filter to supported video MIME types (exclude VPAID/JS)
  const validFiles = mediaFiles.filter(mf => 
    mf.type.toLowerCase().startsWith('video/')
  );

  // Prefer MP4 for maximum compatibility
  const mp4Files = validFiles.filter(
    (mf) => mf.type.includes('mp4')
  );

  const candidates = mp4Files.length > 0 ? mp4Files : validFiles;

  // Sort by closeness to target bitrate, penalizing 4K
  const sorted = [...candidates].sort((a, b) => {
    const aPenalty = a.height > 1080 ? 10000 : 0;
    const bPenalty = b.height > 1080 ? 10000 : 0;

    const aDiff = Math.abs((a.bitrate || 0) - targetBitrate) + aPenalty;
    const bDiff = Math.abs((b.bitrate || 0) - targetBitrate) + bDiff;

    return aDiff - bDiff;
  });

  return sorted[0] || null;
}

private quartilesFired: Set<number> = new Set();

private fireQuartileEvents(percentage: number): void {
  const quartiles = [
    { threshold: 25, event: 'firstQuartile' },
    { threshold: 50, event: 'midpoint' },
    { threshold: 75, event: 'thirdQuartile' }
  ];

  for (const { threshold, event } of quartiles) {
    if (percentage >= threshold && !this.quartilesFired.has(threshold)) {
      this.quartilesFired.add(threshold);
      this.tracker?.track(event);
    }
  }
}

enum VASTErrorCode {
  NO_VAST_RESPONSE = 303,
  GENERAL_WRAPPER_ERROR = 300,
  GENERAL_LINEAR_ERROR = 400,
  FILE_NOT_FOUND = 401,
  MEDIA_NOT_SUPPORTED = 403,
  UNDEFINED_ERROR = 900
}

const sdk = new AdgentSDK({
  container: document.getElementById('ad-container')!,
  vastUrl: 'https://example.com/vast.xml',
  
  // VAST configuration
  maxWrapperDepth: 5,       // Maximum wrapper chain depth
  timeout: 10000,           // VAST fetch timeout (ms)
  targetBitrate: 2500,      // Preferred bitrate (kbps)
  
  // Debugging
  debug: true               // Enable detailed logging
});