internal void Write([NotNull] Stream output)
{
if (_atoms.Count == 0)
{
return;
}
var startPosition = output.Position;
using (var writer = new Mp4Writer(output))
{
// Write the atom header, but we don't know the size yet
writer.Seek(4, SeekOrigin.Current);
writer.WriteBigEndian(0x696c7374); // 'ilst'
foreach (var atom in _atoms)
{
atom.Write(output);
}
// Update the size
var size = output.Position - startPosition;
writer.BaseStream.Position = startPosition;
writer.WriteBigEndian((uint)size);
writer.Seek((int)size - 4, SeekOrigin.Current);
}
}
void UpdateTimeStamp(
[NotNull, ItemNotNull] string[] hierarchy,
DateTime?creationTime,
DateTime?modificationTime)
{
DescendToAtom(hierarchy);
var version = _stream.ReadByte();
_stream.Seek(3, SeekOrigin.Current);
var epoch = new DateTime(1904, 1, 1);
var creationSeconds = creationTime?.Subtract(epoch).TotalSeconds ?? 0;
var modificationSeconds = modificationTime?.Subtract(epoch).TotalSeconds ?? 0;
using (var writer = new Mp4Writer(_stream))
{
if (version == 0)
{
if (creationTime.HasValue)
{
writer.WriteBigEndian((uint)creationSeconds);
}
else
{
writer.Seek(4, SeekOrigin.Current);
}
if (modificationTime.HasValue)
{
writer.WriteBigEndian((uint)modificationSeconds);
}
}
else
{
if (creationTime.HasValue)
{
writer.WriteBigEndian((ulong)creationSeconds);
}
else
{
writer.Seek(8, SeekOrigin.Current);
}
if (modificationTime.HasValue)
{
writer.WriteBigEndian((ulong)modificationSeconds);
}
}
}
}
