(*

 * Hedgewars, a free turn based strategy game

 * Copyright (c) 2004, 2005, 2007, 2008 Andrey Korotaev <unC0Rr@gmail.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; version 2 of the License

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

 *)

{$INCLUDE "options.inc"}

unit uIO;

interface

uses SDLh;

const ipcPort: Word = 0;

var hiTicks: Word;

procedure init_uIO;

procedure SendIPC(s: shortstring);

procedure SendIPCXY(cmd: char; X, Y: SmallInt);

procedure SendIPCRaw(p: pointer; len: Longword);

procedure SendIPCAndWaitReply(s: shortstring);

procedure SendIPCTimeInc;

procedure SendKeepAliveMessage(Lag: Longword);

procedure LoadRecordFromFile(fileName: shortstring);

procedure IPCWaitPongEvent;

procedure IPCCheckSock;

procedure InitIPC;

procedure CloseIPC;

procedure NetGetNextCmd;

implementation

uses uConsole, uConsts, uWorld, uMisc, uLand, uChat, uTeams;

type PCmd = ^TCmd;

     TCmd = packed record

            Next: PCmd;

            loTime: Word;

            case byte of

            1: (len: byte;

                cmd: Char;

                X, Y: SmallInt);

            2: (str: shortstring);

            end;

var	IPCSock: PTCPSocket;

	fds: PSDLNet_SocketSet;

	isPonged: boolean;

	headcmd: PCmd;

	lastcmd: PCmd;

	SendEmptyPacketTicks: LongWord;

function AddCmd(Time: Word; str: shortstring): PCmd;

var command: PCmd;

begin

new(command);

FillChar(command^, sizeof(TCmd), 0);

command^.loTime:= Time;

command^.str:= str;

if command^.cmd <> 'F' then dec(command^.len, 2); // cut timestamp

if headcmd = nil then

   begin

   headcmd:= command;

   lastcmd:= command

   end else

   begin

   lastcmd^.Next:= command;

   lastcmd:= command

   end;

AddCmd:= command;

end;

procedure RemoveCmd;

var tmp: PCmd;

begin

TryDo(headcmd <> nil, 'Engine bug: headcmd = nil', true);

tmp:= headcmd;

headcmd:= headcmd^.Next;

if headcmd = nil then lastcmd:= nil;

dispose(tmp)

end;

procedure InitIPC;

var ipaddr: TIPAddress;

begin

WriteToConsole('Init SDL_Net... ');

SDLTry(SDLNet_Init = 0, true);

fds:= SDLNet_AllocSocketSet(1);

SDLTry(fds <> nil, true);

WriteLnToConsole(msgOK);

WriteToConsole('Establishing IPC connection... ');

SDLTry(SDLNet_ResolveHost(ipaddr, '127.0.0.1', ipcPort) = 0, true);

IPCSock:= SDLNet_TCP_Open(ipaddr);

SDLTry(IPCSock <> nil, true);

WriteLnToConsole(msgOK)

end;

procedure CloseIPC;

begin

	SDLNet_FreeSocketSet(fds);

	SDLNet_TCP_Close(IPCSock);

	SDLNet_Quit();

end;

procedure ParseIPCCommand(s: shortstring);

var loTicks: Word;

begin

case s[1] of

     '!': begin {$IFDEF DEBUGFILE}AddFileLog('Ping? Pong!');{$ENDIF}isPonged:= true; end;

     '?': SendIPC('!');

     'e': ParseCommand(copy(s, 2, Length(s) - 1), true);

     'E': OutError(copy(s, 2, Length(s) - 1), true);

     'W': OutError(copy(s, 2, Length(s) - 1), false);

     'M': CheckLandDigest(s);

     'T': case s[2] of

               'L': GameType:= gmtLocal;

               'D': GameType:= gmtDemo;

               'N': GameType:= gmtNet;

               'S': GameType:= gmtSave;

               else OutError(errmsgIncorrectUse + ' IPC "T" :' + s[2], true) end;

     else

     loTicks:= SDLNet_Read16(@s[byte(s[0]) - 1]);

     AddCmd(loTicks, s);

     {$IFDEF DEBUGFILE}AddFileLog('IPC in: '+s[1]+' ticks '+inttostr(lastcmd^.loTime));{$ENDIF}

     end

end;

procedure IPCCheckSock;

const ss: string = '';

var i: LongInt;

	buf: array[0..255] of byte;

	s: shortstring absolute buf;

begin

if IPCSock = nil then

   exit;

fds^.numsockets:= 0;

SDLNet_AddSocket(fds, IPCSock);

while SDLNet_CheckSockets(fds, 0) > 0 do

	begin

	i:= SDLNet_TCP_Recv(IPCSock, @buf[1], 255 - Length(ss));

	if i > 0 then

		begin

		buf[0]:= i;

		ss:= ss + s;

		while (Length(ss) > 1) and (Length(ss) > byte(ss[1])) do

			begin

			ParseIPCCommand(copy(ss, 2, byte(ss[1])));

			Delete(ss, 1, Succ(byte(ss[1])))

			end

		end else OutError('IPC connection lost', true)

	end;

end;

procedure LoadRecordFromFile(fileName: shortstring);

var f: file;

	ss: string = '';

	i: LongInt;

	buf: array[0..255] of byte;

	s: shortstring absolute buf;

begin

// set RDNLY on file open

filemode:= 0;

assign(f, fileName);

reset(f, 1);

repeat

	BlockRead(f, buf[1], 255 - Length(ss), i);

	if i > 0 then

		begin

		buf[0]:= i;

		ss:= ss + s;

		while (Length(ss) > 1)and(Length(ss) > byte(ss[1])) do

			begin

			ParseIPCCommand(copy(ss, 2, byte(ss[1])));

			Delete(ss, 1, Succ(byte(ss[1])))

			end

		end

until i = 0;

close(f)

end;

procedure SendIPC(s: shortstring);

begin

if IPCSock <> nil then

	begin

	SendEmptyPacketTicks:= 0;

	if s[0]>#251 then s[0]:= #251;

	SDLNet_Write16(GameTicks, @s[Succ(byte(s[0]))]);

	{$IFDEF DEBUGFILE}AddFileLog('IPC send: '+ s[1]);{$ENDIF}

	inc(s[0], 2);

	SDLNet_TCP_Send(IPCSock, @s, Succ(byte(s[0])))

	end

end;

procedure SendIPCRaw(p: pointer; len: Longword);

begin

if IPCSock <> nil then

   begin

   SDLNet_TCP_Send(IPCSock, p, len)

   end

end;

procedure SendIPCXY(cmd: char; X, Y: SmallInt);

var s: shortstring;

begin

s[0]:= #5;

s[1]:= cmd;

SDLNet_Write16(X, @s[2]);

SDLNet_Write16(Y, @s[4]);

SendIPC(s)

end;

procedure SendIPCTimeInc;

const timeinc: shortstring = '#';

begin

SendIPCRaw(@timeinc, 2)

end;

procedure IPCWaitPongEvent;

begin

isPonged:= false;

repeat

   IPCCheckSock;

   SDL_Delay(1)

until isPonged

end;

procedure SendIPCAndWaitReply(s: shortstring);

begin

SendIPC(s);

SendIPC('?');

IPCWaitPongEvent

end;

procedure SendKeepAliveMessage(Lag: Longword);

begin

inc(SendEmptyPacketTicks, Lag);

if (SendEmptyPacketTicks >= cSendEmptyPacketTime) then

	SendIPC('+')

end;

procedure NetGetNextCmd;

var tmpflag: boolean;

	s: shortstring;

	x16, y16: SmallInt;

begin

tmpflag:= true;

while (headcmd <> nil)

	and (tmpflag or (headcmd^.cmd = '#')) // '#' is the only cmd which can be sent within same tick after 'N'

	and ((GameTicks = hiTicks shl 16 + headcmd^.loTime)

		or (headcmd^.cmd = 's') // for these commands time is not specified

		or (headcmd^.cmd = '#')

 		or (headcmd^.cmd = 'b')

		or (headcmd^.cmd = 'F')) do

	begin

	case headcmd^.cmd of

		'+': ; // do nothing - it is just an empty packet

		'#': inc(hiTicks);

		'L': ParseCommand('+left', true);

		'l': ParseCommand('-left', true);

		'R': ParseCommand('+right', true);

		'r': ParseCommand('-right', true);

		'U': ParseCommand('+up', true);

		'u': ParseCommand('-up', true);

		'D': ParseCommand('+down', true);

		'd': ParseCommand('-down', true);

		'Z': ParseCommand('+precise', true);

		'z': ParseCommand('-precise', true);

		'A': ParseCommand('+attack', true);

		'a': ParseCommand('-attack', true);

		'S': ParseCommand('switch', true);

		'j': ParseCommand('ljump', true);

		'J': ParseCommand('hjump', true);

		',': ParseCommand('skip', true);

		's': begin

			s:= copy(headcmd^.str, 2, Pred(headcmd^.len));

			AddChatString(s);

			WriteLnToConsole(s)

			end;

		'b': begin

			s:= copy(headcmd^.str, 2, Pred(headcmd^.len));

			AddChatString(#4 + s);

			WriteLnToConsole(s)

			end;

		'F': TeamGone(copy(headcmd^.str, 2, Pred(headcmd^.len)));

		'N': begin

			tmpflag:= false;

			{$IFDEF DEBUGFILE}AddFileLog('got cmd "N": time '+inttostr(hiTicks shl 16 + headcmd^.loTime)){$ENDIF}

			end;

		'p': begin

			x16:= SDLNet_Read16(@(headcmd^.X));

			y16:= SDLNet_Read16(@(headcmd^.Y));

			doPut(x16, y16, false)

			end;

		'P': begin

			// these are equations solved for CursorPoint

			// SDLNet_Read16(@(headcmd^.X)) == CursorPoint.X - WorldDx;

			// SDLNet_Read16(@(headcmd^.Y)) == cScreenHeight - CursorPoint.Y - WorldDy;

			CursorPoint.X:= SmallInt(SDLNet_Read16(@(headcmd^.X))) + WorldDx;

			CursorPoint.Y:= cScreenHeight - SmallInt(SDLNet_Read16(@(headcmd^.Y))) - WorldDy;

			end;

		'w': ParseCommand('setweap ' + headcmd^.str[2], true);

		't': ParseCommand('taunt ' + headcmd^.str[2], true);

		'g': ParseCommand('newgrave', true);

		'h': ParseCommand('hogsay ' + copy(headcmd^.str, 2, Pred(headcmd^.len)), true);

		'1'..'5': ParseCommand('timer ' + headcmd^.cmd, true);

		#128..char(128 + cMaxSlotIndex): ParseCommand('slot ' + char(byte(headcmd^.cmd) - 79), true)

		else

			OutError('Unexpected protocol command: ' + headcmd^.cmd, True)

		end;

	RemoveCmd

	end;

if (headcmd <> nil) and tmpflag and (not CurrentTeam^.hasGone) then

	TryDo(GameTicks < hiTicks shl 16 + headcmd^.loTime,

			'oops, queue error. in buffer: ' + headcmd^.cmd +

			' (' + inttostr(GameTicks) + ' > ' +

			inttostr(hiTicks shl 16 + headcmd^.loTime) + ')',

			true);

isInLag:= (headcmd = nil) and tmpflag and (not CurrentTeam^.hasGone);

if isInLag then fastUntilLag:= false

end;

procedure init_uIO;

begin

	IPCSock:= nil;

	headcmd:= nil;

	lastcmd:= nil;

	isPonged:= false;	// was const

	hiTicks:= 0;

	SendEmptyPacketTicks:= 0;

end;

end.