using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;

namespace MediaContainers.Matroska;

public class MatroskaCues : List<MatroskaCuePoint>
{
	public void AddCueEntry(EBMLMasterElement element, long segmentOffset)
	{
		if (element == null) { return; }
		if (element.Definition == MatroskaSpecification.Cues)
		{
			foreach (var child in element.Children)
			{
				AddCueEntry(child as EBMLMasterElement, segmentOffset);
			}
		}
		else if (element.Definition == MatroskaSpecification.CuePoint)
		{
			var entry = new MatroskaCuePoint() { SegmentOffset = (ulong)segmentOffset };
			entry.ReadFrom(element);
			Add(entry);
		}
	}

	public async ValueTask Write(EBMLWriter writer, CancellationToken cancellationToken = default)
	{
		await writer.BeginMasterElement(MatroskaSpecification.Cues, cancellationToken);
		for (int i = 0; i < Count; i++) { await this[i].Write(writer, cancellationToken); }
		await writer.EndMasterElement(cancellationToken);
	}

	public EBMLMasterElement ToElement()
	{
		var tracks = new EBMLMasterElement(MatroskaSpecification.Cues);
		foreach (var track in this) { tracks.AddChild(track.ToElement()); }
		return tracks;
	}
}