private void ExtractTree()
{
var stream = new ReadOnlyMemoryStream(_serializedTreeData);
stream.Skip(4); // Skip indentifier
while (!stream.IsOver)
{
var currentMark = (OTBMarkupByte)stream.ReadByte();
if (currentMark < OTBMarkupByte.Escape)
{
// What is under Escape = 0xFD is just prop data. Just skip
continue;
}
switch (currentMark)
{
case OTBMarkupByte.Start:
var nodeType = (OTBNodeType)stream.ReadByte();
AddNodeBegin(stream.Position, nodeType);
break;
case OTBMarkupByte.End:
AddNodeEnd(stream.Position);
break;
case OTBMarkupByte.Escape:
stream.Skip();
break;
default:
throw new InvalidOperationException();
}
}
}
private static OTBNode ExtractOTBTree(byte[] serializedWorldData)
{
var stream = new ReadOnlyMemoryStream(serializedWorldData);
// Skipping the first 4 bytes coz they are used to store a... identifier?
stream.Skip(IdentifierLength);
var treeBuilder = new OTBTreeBuilder(serializedWorldData);
while (!stream.IsOver)
{
var currentMark = (OTBMarkupByte)stream.ReadByte();
if (currentMark < OTBMarkupByte.Escape)
{
/// Since <see cref="OTBMarkupByte"/> can only have values Escape (0xFD), Start (0xFE) and
/// End (0xFF), if currentMark < Escape, then it's just prop data
/// and we can safely skip it.
continue;
}
var nodeType = (OTBNodeType)stream.ReadByte();
switch (currentMark)
{
case OTBMarkupByte.Start:
treeBuilder.AddNodeBegin(
start: stream.Position,
type: nodeType);
break;
case OTBMarkupByte.End:
treeBuilder.AddNodeEnd(stream.Position);
break;
case OTBMarkupByte.Escape:
stream.Skip();
break;
default:
throw new InvalidOperationException();
}
}
return(treeBuilder.BuildTree());
}
/// <summary>
/// Parses data serialized as .otb and returns the deserialized .otb tree structure.
/// </summary>
/// <remarks>
/// Beware that some .otb serializers add a "format identifier" before the data.
/// Maps (worlds?), for instance, contain 4 "format identifier bytes" that should be skiped.
/// </remarks>
public static OTBNode DeserializeOTBData(ReadOnlyMemory <byte> serializedOTBData, int skipFirstBytes)
{
if (skipFirstBytes < 0)
{
throw new ArgumentOutOfRangeException();
}
var relevantData = serializedOTBData.Slice(skipFirstBytes);
var stream = new ReadOnlyMemoryStream(serializedOTBData);
var treeBuilder = new OTBTreeBuilder(serializedOTBData);
while (!stream.IsOver)
{
var currentMark = (OTBMarkupByte)stream.ReadByte();
if (currentMark < OTBMarkupByte.Escape)
{
// Since <see cref="OTBMarkupByte"/> can only have values Escape (0xFD), Start (0xFE) and
// End (0xFF), if currentMark < Escape, then it's just prop data
// and we can safely skip it.
continue;
}
switch (currentMark)
{
case OTBMarkupByte.Start:
var nodeType = (OTBNodeType)stream.ReadByte();
treeBuilder.AddNodeDataBegin(
start: stream.Position,
type: nodeType);
break;
case OTBMarkupByte.End:
treeBuilder.AddNodeEnd(stream.Position - 1);
break;
case OTBMarkupByte.Escape:
stream.Skip();
break;
default:
throw new InvalidOperationException();
}
}
return(treeBuilder.BuildTree());
}