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/* $Id$ */

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#ifdef ENABLE_NETWORK

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#include "../../stdafx.h"

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#include "../../macros.h"

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#include "../../string.h"

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#include "../../helpers.hpp"

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#include "packet.h"

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/**

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 * @file packet.cpp Basic functions to create, fill and read packets.

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 */

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/* Do not want to include functions.h and all required headers */

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extern void NORETURN CDECL error(const char *str, ...);

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/**

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 * Create a packet that is used to read from a network socket

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 * @param cs the socket handler associated with the socket we are reading from

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 */

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Packet::Packet(NetworkSocketHandler *cs)

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{

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	assert(cs != NULL);

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	this->cs   = cs;

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	this->next = NULL;

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	this->pos  = 0; // We start reading from here

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	this->size = 0;

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}

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/**

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 * Creates a packet to send

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 * @param type of the packet to send

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 */

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Packet::Packet(PacketType type)

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{

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	this->cs                   = NULL;

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	this->next                 = NULL;

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	/* Skip the size so we can write that in before sending the packet */

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	this->pos                  = 0;

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	this->size                 = sizeof(PacketSize);

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	this->buffer[this->size++] = type;

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}

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/**

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 * Create a packet for sending

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 * @param type the of packet

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 * @return the newly created packet

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 */

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Packet *NetworkSend_Init(PacketType type)

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{

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	Packet *packet = new Packet(type);

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	/* An error is inplace here, because it simply means we ran out of memory. */

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	if (packet == NULL) error("Failed to allocate Packet");

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	return packet;

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}

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/**

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 * Writes the packet size from the raw packet from packet->size

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 */

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{

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	assert(this->cs == NULL && this->next == NULL);

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	this->buffer[0] = GB(this->size, 0, 8);

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	this->buffer[1] = GB(this->size, 8, 8);

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	this->pos  = 0; // We start reading from here

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}

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/**

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 * The next couple of functions make sure we can send

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 *  uint8, uint16, uint32 and uint64 endian-safe

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 *  over the network. The least significant bytes are

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 *  sent first.

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 *

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 *  So 0x01234567 would be sent as 67 45 23 01.

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 */

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{

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}

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{

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}

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{

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}

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/**

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 *  Sends a string over the network. It sends out

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 *  the string + '\0'. No size-byte or something.

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 * @param data   the string to send

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 */

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{

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	assert(data != NULL);

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}

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/**

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 * Receiving commands

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 * Again, the next couple of functions are endian-safe

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 *  see the comment before NetworkSend_uint8 for more info.

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 */

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/** Is it safe to read from the packet, i.e. didn't we run over the buffer ? */

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{

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	/* Don't allow reading from a quit client/client who send bad data */

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	/* Check if variable is within packet-size */

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		return false;

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	}

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	return true;

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}

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/**

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 * Reads the packet size from the raw packet and stores it in the packet->size

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 */

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{

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	assert(this->cs != NULL && this->next == NULL);

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	this->size  = (PacketSize)this->buffer[0];

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	this->size += (PacketSize)this->buffer[1] << 8;

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}

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/**

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 * Prepares the packet so it can be read

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 */

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{

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	this->ReadRawPacketSize();

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	/* Put the position on the right place */

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	this->pos = sizeof(PacketSize);

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}

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{

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	uint8 n;

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	return n;

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}

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{

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	return n;

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}

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{

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	uint64 n;

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	return n;

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}

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/** Reads a string till it finds a '\0' in the stream */

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{

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	PacketSize pos;

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	char *bufp = buffer;

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	/* Don't allow reading from a closed socket */

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	if (cs->HasClientQuit()) return;

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		*buffer = '\0';

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		/* If size was sooner to zero then the string in the stream

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		 *  skip till the \0, so than packet can be read out correctly for the rest */

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		pos++;

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	}

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	str_validate(bufp);

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}

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#endif /* ENABLE_NETWORK */