Move Chunk class to Lwo2Chunk and into separate file pair.

Refactoring and cleanup.
Adjust Makefile.am.

plugins/model/Lwo2Chunk.cpp

@@ -0,0 +1,94 @@
+#include "Lwo2Chunk.h"
+
+#include "bytestreamutils.h"
+
+namespace model
+{
+
+Lwo2Chunk::Lwo2Chunk(const std::string& identifier_, Type type) :
+	_chunkType(type),
+	identifier(identifier_),
+	stream(std::ios_base::in | std::ios_base::out | std::ios_base::binary)
+{
+	// FORM sub-chunks are normal chunks and have 4 bytes size info
+	// whereas subchunks of e.g. CLIP use 2 bytes of size info
+	_sizeDescriptorByteCount = _chunkType == Type::Chunk ? 4 : 2;
+}
+
+unsigned int Lwo2Chunk::getContentSize() const
+{
+	unsigned int totalSize = 0;
+
+	// Start with the size of the contents 
+	// (don't use seek as we don't know if the client still wants to write stuff)
+	totalSize += static_cast<unsigned int>(stream.str().length());
+
+	if (!subChunks.empty())
+	{
+		// Sum up the size of the subchunks
+		for (const Lwo2Chunk::Ptr& chunk : subChunks)
+		{
+			totalSize += 4; // ID (4 bytes)
+			totalSize += chunk->_sizeDescriptorByteCount; // Subchunk Size Info (can be 4 or 2 bytes)
+
+			// While the child chunk size itself doesn't include padding, we need to respect
+			// it when calculating the size of this parent chunk
+			unsigned int childChunkSize = chunk->getContentSize();
+			totalSize += childChunkSize + (childChunkSize % 2); // add 1 padding byte if odd
+		}
+	}
+
+	// Chunk size can be odd, padding must be handled by client code
+	return totalSize;
+}
+
+Lwo2Chunk::Ptr Lwo2Chunk::addChunk(const std::string& identifier_, Type type)
+{
+	subChunks.push_back(std::make_shared<Lwo2Chunk>(identifier_, type));
+	return subChunks.back();
+}
+
+void Lwo2Chunk::flushBuffer()
+{
+	stream.flush();
+
+	for (const Lwo2Chunk::Ptr& chunk : subChunks)
+	{
+		chunk->flushBuffer();
+	}
+}
+
+void Lwo2Chunk::writeToStream(std::ostream& output)
+{
+	// Flush all buffers before writing to the output stream
+	flushBuffer();
+
+	output.write(identifier.c_str(), identifier.length());
+
+	if (_chunkType == Type::Chunk)
+	{
+		stream::writeBigEndian<uint32_t>(output, getContentSize());
+	}
+	else
+	{
+		stream::writeBigEndian<uint16_t>(output, getContentSize());
+	}
+
+	// Write the direct contents of this chunk
+	std::string str = stream.str();
+	output.write(str.c_str(), str.length());
+
+	// Write all subchunks
+	for (const Lwo2Chunk::Ptr& chunk : subChunks)
+	{
+		chunk->writeToStream(output);
+
+		// Add the padding byte after the chunk
+		if (chunk->getContentSize() % 2 == 1)
+		{
+			output.write("\0", 1);
+		}
+	}
+}
+
+}

plugins/model/Lwo2Chunk.h

@@ -0,0 +1,54 @@
+#pragma once
+
+#include <string>
+#include <memory>
+#include <vector>
+#include <sstream>
+
+namespace model
+{
+
+// Represents a Chunk in the LWO2 file, accepting content
+// through the public stream member. 
+// A Chunk can have contents and/or 1 or more subchunks. 
+class Lwo2Chunk
+{
+public:
+	typedef std::shared_ptr<Lwo2Chunk> Ptr;
+
+	enum class Type
+	{
+		Chunk,
+		SubChunk
+	};
+
+private:
+	Type _chunkType;
+
+	// The number of bytes used for the size info of this chunk
+	unsigned int _sizeDescriptorByteCount;
+
+public:
+	std::string identifier; // the 4-byte ID
+
+	// Child chunks
+	std::vector<Lwo2Chunk::Ptr> subChunks;
+
+	// Stream binary data into here
+	std::stringstream stream;
+
+	Lwo2Chunk(const std::string& identifier_, Type type);
+
+	// Returns the size of this Chunk's content
+	// excluding this Chunk's ID (4 bytes) and Size info (4 bytes)
+	unsigned int getContentSize() const;
+
+	// Adds the specified empty Chunk and returns its reference
+	Lwo2Chunk::Ptr addChunk(const std::string& identifier_, Type type);
+
+	void flushBuffer();
+
+	void writeToStream(std::ostream& output);
+};
+
+}