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#include "os_abstraction.h"

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#include "game.h"

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#include "packet.h"

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#include "../../newgrf_config.h"

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 *

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 *

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 * *** Requesting game information from a server ***

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 *

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 * This describes the on-the-wire structure of the request and reply

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 * packet of the NetworkGameInfo (see game.h) data.

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 *

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 * --- Points of attention ---

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 *  - all > 1 byte integral values are written in little endian,

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 *    unless specified otherwise.

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 *      Thus, 0x01234567 would be sent as {0x67, 0x45, 0x23, 0x01}.

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 *  - all sent strings are of variable length and terminated by a '\0'.

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 *      Thus, the length of the strings is not sent.

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 *  - years that are leap years in the 'days since X' to 'date' calculations:

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 *     (year % 4 == 0) and ((year % 100 != 0) or (year % 400 == 0))

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 *

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 * --- Request ---

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 * Bytes:  Description:

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 *   2       size of the whole packet, in this case 3

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 *   1       type of packet, in this case PACKET_UDP_CLIENT_FIND_SERVER (0)

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 * This packet would look like: { 0x03, 0x00, 0x00 }

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 *

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 * --- Reply ---

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 * Version: Bytes:  Description:

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 *   all      2       size of the whole packet

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 *   all      1       type of packet, in this case PACKET_UDP_SERVER_RESPONSE (1)

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 *   all      1       the version of this packet's structure

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 *

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 *   4+       1       number of GRFs attached (n)

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 *   4+       n * 20  unique identifier for GRF files. Constists of:

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 *                     - one 4 byte variable with the GRF ID

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 *                     - 16 bytes (sent sequentially) for the MD5 checksum

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 *                       of the GRF

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 *

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 *   3+       4       current game date in days since 1-1-0 (DMY)

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 *   3+       4       game introduction date in days since 1-1-0 (DMY)

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 *

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 *   2+       1       maximum number of companies allowed on the server

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 *   2+       1       number of companies on the server

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 *   2+       1       maximum number of spectators allowed on the server

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 *

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 *   1+       var     string with the name of the server

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 *   1+       var     string with the revision of the server

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 *   1+       1       the language run on the server

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 *                    (0 = any, 1 = English, 2 = German, 3 = French)

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 *   1+       1       whether the server uses a password (0 = no, 1 = yes)

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 *   1+       1       maximum number of clients allowed on the server

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 *   1+       1       number of clients on the server

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 *   1+       1       number of spectators on the server

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 *   1 & 2    2       current game date in days since 1-1-1920 (DMY)

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 *   1 & 2    2       game introduction date in days since 1-1-1920 (DMY)

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 *   1+       var     string with the name of the map

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 *   1+       2       width of the map in tiles

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 *   1+       2       height of the map in tiles

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 *   1+       1       type of map:

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 *                    (0 = temperate, 1 = arctic, 2 = desert, 3 = toyland)

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 *   1+       1       whether the server is dedicated (0 = no, 1 = yes)

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bool NetworkUDPListen(SOCKET *udp, const uint32 host, const uint16 port, const bool broadcast);

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void NetworkUDPClose(SOCKET *udp);

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void NetworkSendUDP_Packet(const SOCKET udp, Packet *p, const struct sockaddr_in *recv);

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void NetworkUDPReceive(const SOCKET udp);

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 * @param udp         the socket the packet is received on

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void NetworkHandleUDPPacket(const SOCKET udp, Packet *p, const struct sockaddr_in *client_addr);