Passage à PHP 8 bis

<?php
//console.log("chessgame.inc.php : OK");
// ------------------------------------------------------------------------- //
//  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; either version 2 of the License, or        //
//  (at your option) any later version.                                      //
//                                                                           //
//  You may not change or alter any portion of this comment or credits       //
//  of supporting developers from this source code or any supporting         //
//  source code which is considered copyrighted (c) material of the          //
//  original comment or credit authors.                                      //
//                                                                           //
//  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 //
//  ------------------------------------------------------------------------ //
//  Author: Dave Lerner <http://Dave-L.com>                                  //
//  ------------------------------------------------------------------------ //
//  Adapted from Online Chess Club (OCC) version 1.0.10, which was written   //
//  by Michael Speck <http://lgames.sf.net> and published under the GNU      //
//  General Public License.                                                  //
//  ------------------------------------------------------------------------ //

/**
 * class ChessGame
 *
 * @package chess
 * @subpackage game
*/
define("gsRunning"   , 0);
define("gsMate"      , 1);
define("gsStalemate" , 2);
define("gsCheck"     , 3);


define('_MD_CHESS_ERROR',             'Error');
define('_MD_CHESS_FENBAD_LENGTH',          'invalid length');
define('_MD_CHESS_FENBAD_FIELD_COUNT',     'wrong number of fields');
define('_MD_CHESS_FENBAD_PP_INVALID',      'piece placement invalid');
define('_MD_CHESS_FENBAD_AC_INVALID',      'active color invalid');
define('_MD_CHESS_FENBAD_CA_INVALID',      'castling availability invalid');
define('_MD_CHESS_FENBAD_EP_INVALID',      'en passant target_square invalid');
define('_MD_CHESS_FENBAD_HC_INVALID',      'halfmove clock invalid');
define('_MD_CHESS_FENBAD_FN_INVALID',      'fullmove number invalid');
define('_MD_CHESS_FENBAD_MATERIAL',        'insufficient mating material');
define('_MD_CHESS_FENBAD_IN_CHECK',        'player to move cannot have opponent in check');
define('_MD_CHESS_FENBAD_CA_INCONSISTENT', 'castling availability inconsistent with piece placement');
define('_MD_CHESS_FENBAD_EP_COLOR',        'en passant target square wrong color');
define('_MD_CHESS_FENBAD_EP_NO_PAWN',      'en passant target square for nonexistent pawn');

/**
 * The purpose of this class is to handle chess moves.
 *
 * An instantiation of this class comprises the data essential for handling chess
 * moves in a specific game, and provides the requisite methods.
 *
 * - Input:      Game state and proposed move.
 * - Processing: Check the legality of the move, and update the game state if the move is legal.
 * - Output:     Indication of the move's legality, and the (possibly) updated game state.
 *
 * In addition to the above, there are utility methods for converting between Standard Algebraic
 * Notation (SAN) and a notation similar to Long Algebraic Notation.
 *
 * @package chess
 * @subpackage game
 */
class ChessGame {

	/**
		* Indicates whether object is valid.
		*
		* If empty string (''), indicates this is a valid object; otherwise contains an error message.
	 * Should be checked after creating an instance of this class.
		*
		* @var string $error
		*/
	var $error;

	 /**
		* gamestate
		*
	 * The game state is represented as an array with the following elements:
	 *
	 *  - 'fen_piece_placement'
	 *  - 'fen_active_color'
	 *  - 'fen_castling_availability'
	 *  - 'fen_en_passant_target_square'
	 *  - 'fen_halfmove_clock'
	 *  - 'fen_fullmove_number'
	 *  - 'pgn_result'
	 *  - 'pgn_fen'
	 *  - 'pgn_movetext'
	 *
	 * The elements prefixed with 'fen_' are standard Forsyth-Edwards Notation (FEN) elements,
	 * and the elements prefixed with 'pgn_' are standard Portable Game Notation (PGN) elements.
	 *
	 * Each element is a string.
		*
		* @var array $gamestate
		*/
	var $gamestate;

	 /**
		* board
		*
	 * A 64-element array, constructed from fen_piece_placement, is used for handling moves.
	 * Its indices are related to the standard tile coordinates as follows:
	 *
		* <pre>
	 * 8 | 56 57 58 59 60 61 62 63
	 * 7 | 48 49 50 51 52 53 54 55
	 * 6 | 40 41 42 43 44 45 46 47
	 * 5 | 32 33 34 35 36 37 38 39
	 * 4 | 24 25 26 27 28 29 30 31
	 * 3 | 16 17 18 19 20 21 22 23
	 * 2 |  8  9 10 11 12 13 14 15
	 * 1 |  0  1  2  3  4  5  6  7
	 *    ------------------------
	 *      a  b  c  d  e  f  g  h
		* </pre>
	 *
	 * For example, $board[17] is tile b3 and $board[55] is tile h7.
		*
		* @var array $board
		*/
	var $board;

	 /**
		* for auto-completion of moves
		* @var string $ac_move
		*/
	var $ac_move;

	 /**
		* array of white's pieces
		* @var array $w_figures
		*/
	var $w_figures;

	 /**
		* array of black's pieces
		* @var array $b_figures
		*/
	var $b_figures;


	 /**
	 * updated by handleMove, not used now but might be used in future
		* @var string $last_move
		*/
	var $last_move;

	 /**
	 * updated by handleMove, not used now but might be used in future
		* @var string $captured_piece
		*/
	var $captured_piece;

// --------------
// PUBLIC METHODS
// --------------

/**
 * constructor
 *
 * If a failure occurs, $this->error is set to a string containing an error message;
 * otherwise $this->error is set to an empty string.
 *
 * Example:
 * <pre>
 *    $chessgame = new ChessGame($fen);
 *    if (!empty($chessgame->error)) {
 *      echo "'$fen' invalid: $chessgame->error\n";
 *    }
 * </pre>
 *
 * @param mixed $param  If $param is an array, an existing game is loaded using $param as the nine-element gamestate array described above.
 * If $param is a non-empty string, a new game is created using $param as a FEN setup position.
 * Otherwise, a new game is created using the standard starting position.
 */
function __construct($param = null)
{
	// for now
	$this->browsing_mode  = 0;

	if (is_array($param)) {

		$this->gamestate = $param;
		$this->error     = '';

	} elseif (is_string($param) and !empty($param)) {

		$this->error = $this->init_gamestate($param);

	} else {

		$this->init_gamestate();
		$this->error = '';
	}
}

/**
 * Handle a move.
 *
 * @param string $move
 * @return array A two-element array:
 *  - $move_performed: true if the move was performed and the game state has been updated, false otherwise
 *  - $move_result_text: text message
 */
function move($move)
{
	empty($this->error) or trigger_error(_MD_CHESS_ERROR, E_USER_ERROR);
	return $this->handleMove($move);
}

/**
 * get game state
 *
 * @return array
 */
 //echo "Bonjour";
 //echo "<br/>";
function gamestate()
{
	empty($this->error) or trigger_error(_MD_CHESS_ERROR, E_USER_ERROR);
	return $this->gamestate;
}

/*if (empty($this->error) === false) 
{
     trigger_error(_MD_JEU_ERROR, E_USER_ERROR);
}
*/

/*$x = $this->gamestate;
echo $x;
echo "<br/>";
exit ("Stop");*/

// ----------------------------------------------------------------
// PRIVATE METHODS - intended for use only by methods of this class
// ----------------------------------------------------------------

/**
 * Initialize gamestate for a new game.
 *
 * If a non-empty string $fen is provided, the game is initialized using $fen as a FEN setup position.
 * Otherwise the game is initialized using the standard starting position.
 *
 * @param  string  $fen
 * @return string  empty string on success, or error message on failure
 *
 * @access private
 */
function init_gamestate($fen = null)
{
	$this->gamestate = array();

	if (!empty($fen)) {
		$setup = true;
	} else {
		$setup = false;
		$fen   = 'rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1';
	}

	// check that data is not unreasonably short or long
	if (strlen($fen) < 23 or strlen($fen) > 100) {
		return _MD_CHESS_FENBAD_LENGTH; // invalid length
	}

	$fen_data = explode(' ', $fen);

	if (count($fen_data) != 6) {
		return _MD_CHESS_FENBAD_FIELD_COUNT; // wrong number of fields
	}

	$this->gamestate['fen_piece_placement']          = $fen_data[0];
	$this->gamestate['fen_active_color']             = $fen_data[1];
	$this->gamestate['fen_castling_availability']    = $fen_data[2];
	$this->gamestate['fen_en_passant_target_square'] = $fen_data[3];
	$this->gamestate['fen_halfmove_clock']           = $fen_data[4];
	$this->gamestate['fen_fullmove_number']          = $fen_data[5];
	$this->gamestate['pgn_fen']                      = $setup ? $fen : null;
	$this->gamestate['pgn_result']                   = '*';
	$this->gamestate['pgn_movetext']                 = '*';
var_dump ($this->gamestate['fen_en_passant_target_square']);
	if (!$this->fen_piece_placement_to_board())
	{
		return _MD_CHESS_FENBAD_PP_INVALID; // piece_placement invalid
	}
	elseif ($this->gamestate['fen_active_color'] != 'w' and $this->gamestate['fen_active_color'] != 'b')
	{
		return _MD_CHESS_FENBAD_AC_INVALID; // active_color invalid
	}
	// Since fen_piece_placement_to_board() checked $fen for the correct number of fields above, $castling_availability is non-empty.
	elseif ($this->gamestate['fen_castling_availability'] != '-' and !preg_match('/^(?:K\w?)?(?:Q\w?)?(?:k\w?)?(?:q\w?)?$/', $this->gamestate['fen_castling_availability']))
	{
		return _MD_CHESS_FENBAD_CA_INVALID; // castling_availability invalid
	}
	elseif ($this->gamestate['fen_en_passant_target_square'] != '-' and !preg_match('/^[a-h][36]$/', $this->gamestate['fen_en_passant_target_square']))
	{
		return _MD_CHESS_FENBAD_EP_INVALID; // en_passant_target_square invalid
	}
	elseif (!preg_match('/^\d{0,4}$/', $this->gamestate['fen_halfmove_clock']))
	{
		return _MD_CHESS_FENBAD_HC_INVALID; // halfmove_clock invalid
	}
	elseif (!preg_match('/^\d{0,4}$/', $this->gamestate['fen_fullmove_number']) or $this->gamestate['fen_fullmove_number'] < 1)
	{
		return _MD_CHESS_FENBAD_FN_INVALID; // fullmove_number invalid
	}
	elseif ($this->insufficient_mating_material())
	{
		return _MD_CHESS_FENBAD_MATERIAL; // insufficient mating material
	}
	elseif (($this->gamestate['fen_active_color'] == 'w' and $this->kingIsUnderAttack('b', 'w'))
		or   ($this->gamestate['fen_active_color'] == 'b' and $this->kingIsUnderAttack('w', 'b')))
	{
		return _MD_CHESS_FENBAD_IN_CHECK; // player to move cannot have opponent in check
	}
	elseif ((strstr($this->gamestate['fen_castling_availability'], 'K') and ($this->board[ 4] != 'wK' or $this->board[ 7] != 'wR'))
		or   (strstr($this->gamestate['fen_castling_availability'], 'Q') and ($this->board[ 4] != 'wK' or $this->board[ 0] != 'wR'))
		or   (strstr($this->gamestate['fen_castling_availability'], 'k') and ($this->board[60] != 'bK' or $this->board[63] != 'bR'))
		or   (strstr($this->gamestate['fen_castling_availability'], 'q') and ($this->board[60] != 'bK' or $this->board[56] != 'bR')))
	{
		return _MD_CHESS_FENBAD_CA_INCONSISTENT; // castling availability inconsistent with piece placement
	}
	elseif ($this->gamestate['fen_en_passant_target_square'] != '-'  && (
              ($this->gamestate['fen_en_passant_target_square'][1] == 3 && $this->gamestate['fen_active_color'] != 'b')
		||  ($this->gamestate['fen_en_passant_target_square'][1] == 6 && $this->gamestate['fen_active_color'] != 'w')
		))
	{
		return _MD_CHESS_FENBAD_EP_COLOR; // en passant target square wrong color
	}
	//elseif ($this->gamestate['fen_en_passant_target_square'] != '-' and $this->gamestate['fen_en_passant_target_square']{1} == 3
		//and $this->board[$this->boardCoordToIndex($this->gamestate['fen_en_passant_target_square']{0} . '4')] != 'wP')
	elseif ($this->gamestate['fen_en_passant_target_square'] != '-' and $this->gamestate['fen_en_passant_target_square'][1] == 3
		and $this->board[$this->boardCoordToIndex($this->gamestate['fen_en_passant_target_square'][0] . '4')] != 'wP')	
	{
		return _MD_CHESS_FENBAD_EP_NO_PAWN; // en passant target square for nonexistent pawn
	}
	//elseif ($this->gamestate['fen_en_passant_target_square'] != '-' and $this->gamestate['fen_en_passant_target_square']{1} == 6
		//and $this->board[$this->boardCoordToIndex($this->gamestate['fen_en_passant_target_square']{0} . '5')] != 'bP')
	elseif ($this->gamestate['fen_en_passant_target_square'] != '-' and $this->gamestate['fen_en_passant_target_square'][1] == 6
		and $this->board[$this->boardCoordToIndex($this->gamestate['fen_en_passant_target_square'][0] . '5')] != 'bP')	
	{
		return _MD_CHESS_FENBAD_EP_NO_PAWN; // en passant target square for nonexistent pawn
	}

	#echo "In " . __CLASS__ . '::' . __FUNCTION__ . "\n";#*#DEBUG#
	#var_dump('gamestate', $this->gamestate);#*#DEBUG#

	// save the current FEN to the board
	$this->fen_piece_placement_to_board( );
	return ''; // successful
}