/*
 * Copyright (c) 2012 Yoann Blein
 * Licensed under the simplified BSD license.
 * See Documentation/Licenses/BSD-simplified.txt for more information.
 */

#include <Swiften/ScreenSharing/VP8RTPParser.h>

#include <Swiften/ScreenSharing/VP8Decoder.h>

namespace Swift {

VP8RTPParser::VP8RTPParser(VideoDecoder* decoder)
	: decoder(decoder), firstPacket(true), pictureID(0)
{
}

void VP8RTPParser::newPayloadReceived(const uint8_t* data, size_t len, bool hasMarker)
{
	size_t headerSize = 1;

	// Payload descriptor
	uint8_t req = data[0];
	if (firstPacket && !(req & SBit)) { /* Error */ }

	if (req & XBit) { // Extension byte is present
		uint8_t optX = data[headerSize++];
		if (optX & IBit) { // PictureID byte is present
			uint8_t optI = data[headerSize++];
			pictureID = optI >> 1;
		}
	}

	// Payload header
	if (firstPacket) {
		firstPacket = false;
		uint8_t o1 = data[headerSize];
		showFrame = (o1 & 1);
		isKeyFrame = (o1 & HBit);
		o1 >>= Size0BitShift;
		frameSize = o1 + 8 * data[headerSize + 1] + 2048 * data[headerSize + 2];

		headerSize += 3;
	}

	buffer.insert(buffer.end(), data + headerSize, data + len);

	if (hasMarker || buffer.size() >= frameSize) {
		// Frame received
		decoder->decodeFrame(buffer, pictureID);
		buffer.clear();
		firstPacket = true;
	}
}

}