/*
===========================================================================

Doom 3 BFG Edition GPL Source Code
Copyright (C) 1993-2012 id Software LLC, a ZeniMax Media company. 

This file is part of the Doom 3 BFG Edition GPL Source Code ("Doom 3 BFG Edition Source Code").  

Doom 3 BFG Edition Source Code 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, either version 3 of the License, or
(at your option) any later version.

Doom 3 BFG Edition Source Code 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 Doom 3 BFG Edition Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the Doom 3 BFG Edition Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 BFG Edition Source Code.  If not, please request a copy in writing from id Software at the address below.

If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.

===========================================================================
*/

#ifndef __USERCMDGEN_H__
#define __USERCMDGEN_H__

#include "../sys/sys_session.h"

/*
===============================================================================

	Samples a set of user commands from player input.

===============================================================================
*/

// usercmd_t->button bits
const int BUTTON_ATTACK			= BIT(0);
const int BUTTON_RUN			= BIT(1);
const int BUTTON_ZOOM			= BIT(2);
const int BUTTON_SCORES			= BIT(3);
const int BUTTON_USE			= BIT(4);
const int BUTTON_JUMP			= BIT(5);
const int BUTTON_CROUCH			= BIT(6);
const int BUTTON_CHATTING		= BIT(7);

// usercmd_t->impulse commands
const int IMPULSE_0				= 0;			// weap 0
const int IMPULSE_1				= 1;			// weap 1
const int IMPULSE_2				= 2;			// weap 2
const int IMPULSE_3				= 3;			// weap 3
const int IMPULSE_4				= 4;			// weap 4
const int IMPULSE_5				= 5;			// weap 5
const int IMPULSE_6				= 6;			// weap 6
const int IMPULSE_7				= 7;			// weap 7
const int IMPULSE_8				= 8;			// weap 8
const int IMPULSE_9				= 9;			// weap 9
const int IMPULSE_10			= 10;			// weap 10
const int IMPULSE_11			= 11;			// weap 11
const int IMPULSE_12			= 12;			// weap 12
const int IMPULSE_13			= 13;			// weap reload
const int IMPULSE_14			= 14;			// weap next
const int IMPULSE_15			= 15;			// weap prev
const int IMPULSE_16			= 16;			// toggle flashlight on/off
const int IMPULSE_18			= 18;			// center view
const int IMPULSE_19			= 19;			// show PDA/SCORES
const int IMPULSE_22			= 22;			// spectate
const int IMPULSE_25			= 25;			// Envirosuit light
const int IMPULSE_27			= 27;			// Chainsaw
const int IMPULSE_28			= 28;			// quick 0
const int IMPULSE_29			= 29;			// quick 1
const int IMPULSE_30			= 30;			// quick 2
const int IMPULSE_31			= 31;			// quick 3

class usercmd_t {
public:
	usercmd_t() :
		forwardmove(),
		rightmove(),
		buttons(),
		clientGameMilliseconds( 0 ),
		serverGameMilliseconds( 0 ),
		fireCount( 0 ),
		mx(),
		my(),
		impulse(),
		impulseSequence(),
		pos( 0.0f, 0.0f, 0.0f ),
		speedSquared( 0.0f )
	{
		angles[0] = 0;
		angles[1] = 0;
		angles[2] = 0;
	}

	// Syncronized
	short		angles[3];						// view angles
	signed char	forwardmove;					// forward/backward movement
	signed char	rightmove;						// left/right movement
	byte		buttons;						// buttons
	int			clientGameMilliseconds;			// time this usercmd was sent from the client
	int			serverGameMilliseconds;			// interpolated server time this was applied on
	uint16		fireCount;						// number of times we've fired

	// Not syncronized
	byte		impulse;						// impulse command
	byte		impulseSequence;				// incremented every time there's a new impulse

	short		mx;								// mouse delta x
	short		my;								// mouse delta y

	// Clients are authoritative on their positions
	idVec3		pos;
	float		speedSquared;

public:
	void		Serialize( class idSerializer & s, const usercmd_t & base );
	void		ByteSwap();						// on big endian systems, byte swap the shorts and ints
	bool		operator==( const usercmd_t &rhs ) const;
};

typedef enum {
	INHIBIT_SESSION = 0,
	INHIBIT_ASYNC
} inhibit_t;

typedef enum {
	UB_NONE,

	UB_MOVEUP,
	UB_MOVEDOWN,
	UB_LOOKLEFT,
	UB_LOOKRIGHT,
	UB_MOVEFORWARD,
	UB_MOVEBACK,
	UB_LOOKUP,
	UB_LOOKDOWN,
	UB_MOVELEFT,
	UB_MOVERIGHT,

	UB_ATTACK,
	UB_SPEED,
	UB_ZOOM,
	UB_SHOWSCORES,
	UB_USE,

	UB_IMPULSE0,
	UB_IMPULSE1,
	UB_IMPULSE2,
	UB_IMPULSE3,
	UB_IMPULSE4,
	UB_IMPULSE5,
	UB_IMPULSE6,
	UB_IMPULSE7,
	UB_IMPULSE8,
	UB_IMPULSE9,
	UB_IMPULSE10,
	UB_IMPULSE11,
	UB_IMPULSE12,
	UB_IMPULSE13,
	UB_IMPULSE14,
	UB_IMPULSE15,
	UB_IMPULSE16,
	UB_IMPULSE17,
	UB_IMPULSE18,
	UB_IMPULSE19,
	UB_IMPULSE20,
	UB_IMPULSE21,
	UB_IMPULSE22,
	UB_IMPULSE23,
	UB_IMPULSE24,
	UB_IMPULSE25,
	UB_IMPULSE26,
	UB_IMPULSE27,
	UB_IMPULSE28,
	UB_IMPULSE29,
	UB_IMPULSE30,
	UB_IMPULSE31,

	UB_MAX_BUTTONS
} usercmdButton_t;

typedef struct {
	const char *string;
	usercmdButton_t	button;
} userCmdString_t;

class idUsercmdGen {
public:
	virtual				~idUsercmdGen() {}

	// Sets up all the cvars and console commands.
	virtual	void		Init() = 0;

	// Prepares for a new map.
	virtual void		InitForNewMap() = 0;

	// Shut down.
	virtual void		Shutdown() = 0;

	// Clears all key states and face straight.
	virtual	void		Clear() = 0;

	// Clears view angles.
	virtual void		ClearAngles() = 0;

	// When the console is down or the menu is up, only emit default usercmd, so the player isn't moving around.
	// Each subsystem (session and game) may want an inhibit will OR the requests.
	virtual void		InhibitUsercmd( inhibit_t subsystem, bool inhibit ) = 0;

	// Set a value that can safely be referenced by UsercmdInterrupt() for each key binding.
	virtual	int			CommandStringUsercmdData( const char *cmdString ) = 0;

	// Continuously modified, never reset. For full screen guis.
	virtual void		MouseState( int *x, int *y, int *button, bool *down ) = 0;

	// Directly sample a button.
	virtual int			ButtonState( int key ) = 0;

	// Directly sample a keystate.
	virtual int			KeyState( int key ) = 0;

	// called at vsync time
	virtual void		BuildCurrentUsercmd( int deviceNum ) = 0;

	// return the current usercmd
	virtual usercmd_t	GetCurrentUsercmd() = 0;
};

extern idUsercmdGen	*usercmdGen;
extern userCmdString_t	userCmdStrings[];

/*
================================================
idUserCmdMgr
================================================
*/
class idUserCmdMgr {
public:
	idUserCmdMgr() {
		SetDefaults();
	}
	
	void SetDefaults() {
		for ( int i = 0; i < cmdBuffer.Num(); ++i ) {
			cmdBuffer[i].Zero();
		}
		writeFrame.Zero();
		readFrame.Memset( -1 );
	}

	// Set to 128 for now
	// Temp fix for usercmds overflowing  Correct fix is to process usercmds as they come in (like q3), rather then buffer them up.
	static const int USERCMD_BUFFER_SIZE = 128;
	
	//usercmd_t	cmdBuffer[ USERCMD_BUFFER_SIZE ][ MAX_PLAYERS ];
	id2DArray< usercmd_t, USERCMD_BUFFER_SIZE, MAX_PLAYERS >::type	cmdBuffer;
	idArray< int, MAX_PLAYERS >			writeFrame;	//"where we write to next"
	idArray< int, MAX_PLAYERS >			readFrame;	//"the last frame we read"	
	
	void PutUserCmdForPlayer( int playerIndex, const usercmd_t & cmd ) {
		cmdBuffer[ writeFrame[ playerIndex ] % USERCMD_BUFFER_SIZE ][ playerIndex ] = cmd;		
		if ( writeFrame[ playerIndex ] - readFrame[ playerIndex ] + 1 > USERCMD_BUFFER_SIZE ) {
			readFrame[ playerIndex ] = writeFrame[ playerIndex ] - USERCMD_BUFFER_SIZE / 2;		// Set to middle of buffer as a temp fix until we can catch the client up correctly
			idLib::Printf( "PutUserCmdForPlayer: buffer overflow.\n" );
		}
		writeFrame[ playerIndex ]++;
	}

	void ResetPlayer( int playerIndex ) {
		for ( int i = 0; i < USERCMD_BUFFER_SIZE; i++ ) {
			memset( &cmdBuffer[i][playerIndex], 0, sizeof( usercmd_t ) );
		}
		writeFrame[ playerIndex ] = 0;
		readFrame[ playerIndex ] = -1;
	}

	bool HasUserCmdForPlayer( int playerIndex, int buffer=0 ) const {
		// return true if the last frame we read from (+ buffer) is < the last frame we wrote to
		// (remember writeFrame is where we write to *next*. readFrame is where we last read from last)		
		bool hasCmd = ( readFrame[ playerIndex ] + buffer < writeFrame[playerIndex] - 1 );
		return hasCmd;
	}

	bool HasUserCmdForClientTimeBuffer( int playerIndex, int millisecondBuffer ) {
		// return true if there is at least one command in addition to enough
		// commands to cover the buffer.
		if ( millisecondBuffer == 0 ) {
			return HasUserCmdForPlayer( playerIndex );
		}

		if ( GetNumUnreadFrames( playerIndex ) < 2 ) {
			return false;
		}
		
		const int index = readFrame[ playerIndex ] + 1;
		const usercmd_t & firstCmd = cmdBuffer[ index % USERCMD_BUFFER_SIZE ][ playerIndex ];
		const usercmd_t & lastCmd = NewestUserCmdForPlayer( playerIndex );

		const int timeDelta = lastCmd.clientGameMilliseconds - firstCmd.clientGameMilliseconds;

		const bool isTimeGreaterThanBuffer = timeDelta > millisecondBuffer;

		return isTimeGreaterThanBuffer;
	}

	const usercmd_t & NewestUserCmdForPlayer( int playerIndex ) {
		int index = Max( writeFrame[ playerIndex ] - 1, 0 );
		return cmdBuffer[ index % USERCMD_BUFFER_SIZE ][ playerIndex ];
	}
	
	const usercmd_t & GetUserCmdForPlayer( int playerIndex ) {
		//Get the next cmd we should process (not necessarily the newest)
		//Note we may have multiple reads for every write .
		//We want to:
		// A) never skip over a cmd (unless we call MakeReadPtrCurrentForPlayer() ).
		// B) never get ahead of the writeFrame	
		
		//try to increment before reading (without this we may read the same input twice
		//and be a frame behind our writes in the case of)
		if ( readFrame[ playerIndex ] < writeFrame[ playerIndex ] - 1 ) {
			readFrame[ playerIndex ]++;
		}

		//grab the next command in the readFrame buffer		
		int index = readFrame[ playerIndex ]; 
		usercmd_t & result = cmdBuffer[ index % USERCMD_BUFFER_SIZE ][ playerIndex ];		
		return result;
	}
	
	int GetNextUserCmdClientTime( int playerIndex ) const {
		if ( !HasUserCmdForPlayer( playerIndex ) ) {
			return 0;
		}

		const int index = readFrame[ playerIndex ] + 1;
		const usercmd_t & cmd = cmdBuffer[ index % USERCMD_BUFFER_SIZE ][ playerIndex ];
		return cmd.clientGameMilliseconds;
	}

	// Hack to let the player inject his position into the correct usercmd.
	usercmd_t & GetWritableUserCmdForPlayer( int playerIndex ) {
		//Get the next cmd we should process (not necessarily the newest)
		//Note we may have multiple reads for every write .
		//We want to:
		// A) never skip over a cmd (unless we call MakeReadPtrCurrentForPlayer() ).
		// B) never get ahead of the writeFrame	
		
		//try to increment before reading (without this we may read the same input twice
		//and be a frame behind our writes in the case of)
		if ( readFrame[ playerIndex ] < writeFrame[ playerIndex ] - 1 ) {
			readFrame[ playerIndex ]++;
		}

		//grab the next command in the readFrame buffer		
		int index = readFrame[ playerIndex ]; 
		usercmd_t & result = cmdBuffer[ index % USERCMD_BUFFER_SIZE ][ playerIndex ];		
		return result;
	}

	void MakeReadPtrCurrentForPlayer( int playerIndex ) { 
		//forces us to the head of our read buffer. As if we have processed every cmd available to us and now HasUserCmdForPlayer() returns FALSE
		//Note we do -1 to point us to the last written cmd.
		//If a read before the next write, you will get the last write. (not garbage)
		//If a write is made before the next read, you *will* get the new write ( b/c GetUserCmdForPlayer pre increments)

		//After calling this, HasUserCmdForPlayer() will return FALSE;
		readFrame[ playerIndex ] = writeFrame[ playerIndex ] - 1; 
	}

	void SkipBufferedCmdsForPlayer( int playerIndex ) {
		// Similar to MakeReadPtrCurrentForPlayer, except:
		// -After calling this, HasUserCmdForPlayer() will return TRUE iff there was >= 1 fresh cmd in the buffer
		// Also, If there are no fresh frames, we wont roll the readFrame back
		readFrame[ playerIndex ] = Max( readFrame[ playerIndex ], writeFrame[ playerIndex ] - 2 );
	}

	int GetNumUnreadFrames( int playerIndex ) {
		return (writeFrame[ playerIndex ] - 1) - readFrame[ playerIndex ];
	}
	
	int GetPlayerCmds( int user, usercmd_t ** buffer, const int bufferSize ) { 
		// Fallback to getting cmds from the userCmdMgr
		int start = Max( writeFrame[user] - Min( bufferSize, USERCMD_BUFFER_SIZE ), 0 );
		int numCmds = writeFrame[user] - start;

		for ( int i = 0; i < numCmds; i++ ) {
			int index = ( start + i ) % USERCMD_BUFFER_SIZE;
			buffer[i] = &cmdBuffer[ index ][ user ];
		}
		return numCmds;
	}
};

#endif /* !__USERCMDGEN_H__ */