src/chess.lua

   1 local realchess = {}
   2 screwdriver = screwdriver or {}
   3
   4 local function index_to_xy(idx)
   5         idx = idx - 1
   6         local x = idx % 8
   7         local y = (idx - x) / 8
   8         return x, y
   9 end
  10
  11 local function xy_to_index(x, y)
  12         return x + y * 8 + 1
  13 end
  14
  15 local chat_prefix = minetest.colorize("#FFFF00", "[Chess] ")
  16 local letters = {'A','B','C','D','E','F','G','H'}
  17
  18 local pieces = {
  19         "realchess:rook_black_1",
  20         "realchess:knight_black_1",
  21         "realchess:bishop_black_1",
  22         "realchess:queen_black",
  23         "realchess:king_black",
  24         "realchess:bishop_black_2",
  25         "realchess:knight_black_2",
  26         "realchess:rook_black_2",
  27         "realchess:pawn_black_1",
  28         "realchess:pawn_black_2",
  29         "realchess:pawn_black_3",
  30         "realchess:pawn_black_4",
  31         "realchess:pawn_black_5",
  32         "realchess:pawn_black_6",
  33         "realchess:pawn_black_7",
  34         "realchess:pawn_black_8",
  35         '','','','','','','','','','','','','','','','',
  36         '','','','','','','','','','','','','','','','',
  37         "realchess:pawn_white_1",
  38         "realchess:pawn_white_2",
  39         "realchess:pawn_white_3",
  40         "realchess:pawn_white_4",
  41         "realchess:pawn_white_5",
  42         "realchess:pawn_white_6",
  43         "realchess:pawn_white_7",
  44         "realchess:pawn_white_8",
  45         "realchess:rook_white_1",
  46         "realchess:knight_white_1",
  47         "realchess:bishop_white_1",
  48         "realchess:queen_white",
  49         "realchess:king_white",
  50         "realchess:bishop_white_2",
  51         "realchess:knight_white_2",
  52         "realchess:rook_white_2"
  53 }
  54
  55 local pieces_str, x = "", 0
  56 for i = 1, #pieces do
  57         local p = pieces[i]:match(":(%w+_%w+)")
  58         if pieces[i]:find(":(%w+)_(%w+)") and not pieces_str:find(p) then
  59                 pieces_str = pieces_str .. x .. "=" .. p .. ".png,"
  60                 x = x + 1
  61         end
  62 end
  63 pieces_str = pieces_str .. "69=mailbox_blank16.png"
  64
  65 local fs = [[
  66         size[14.7,10;]
  67         no_prepend[]
  68         bgcolor[#080808BB;true]
  69         background[0,0;14.7,10;chess_bg.png]
  70         list[context;board;0.3,1;8,8;]
  71         listcolors[#00000000;#00000000;#00000000;#30434C;#FFF]
  72         tableoptions[background=#00000000;highlight=#00000000;border=false]
  73         button[10.5,8.5;2,2;new;New game]
  74 ]] ..  "tablecolumns[image," .. pieces_str ..
  75                 ";text;color;text;color;text;image," .. pieces_str .. "]"
  76
  77 function realchess.init(pos)
  78         local meta = minetest.get_meta(pos)
  79         local inv = meta:get_inventory()
  80
  81         meta:set_string("formspec", fs)
  82         meta:set_string("infotext", "Chess Board")
  83         meta:set_string("playerBlack", "")
  84         meta:set_string("playerWhite", "")
  85         meta:set_string("lastMove", "")
  86         meta:set_string("winner", "")
  87
  88         meta:set_int("lastMoveTime", 0)
  89         meta:set_int("castlingBlackL", 1)
  90         meta:set_int("castlingBlackR", 1)
  91         meta:set_int("castlingWhiteL", 1)
  92         meta:set_int("castlingWhiteR", 1)
  93
  94         meta:set_string("moves", "")
  95         meta:set_string("eaten", "")
  96
  97         inv:set_list("board", pieces)
  98         inv:set_size("board", 64)
  99 end
 100
 101 function realchess.move(pos, from_list, from_index, to_list, to_index, _, player)
 102         if from_list ~= "board" and to_list ~= "board" then
 103                 return 0
 104         end
 105
 106         local playerName = player:get_player_name()
 107         local meta = minetest.get_meta(pos)
 108
 109         if meta:get_string("winner") ~= "" then
 110                 return 0
 111         end
 112
 113         local inv = meta:get_inventory()
 114         local pieceFrom = inv:get_stack(from_list, from_index):get_name()
 115         local pieceTo = inv:get_stack(to_list, to_index):get_name()
 116         local lastMove = meta:get_string("lastMove")
 117         local thisMove -- will replace lastMove when move is legal
 118         local playerWhite = meta:get_string("playerWhite")
 119         local playerBlack = meta:get_string("playerBlack")
 120
 121         if pieceFrom:find("white") then
 122                 if playerWhite ~= "" and playerWhite ~= playerName then
 123                         minetest.chat_send_player(playerName, chat_prefix .. "Someone else plays white pieces!")
 124                         return 0
 125                 end
 126                 if lastMove ~= "" and lastMove ~= "black" then
 127                         return 0
 128                 end
 129                 if pieceTo:find("white") then
 130                         -- Don't replace pieces of same color
 131                         return 0
 132                 end
 133                 playerWhite = playerName
 134                 thisMove = "white"
 135         elseif pieceFrom:find("black") then
 136                 if playerBlack ~= "" and playerBlack ~= playerName then
 137                         minetest.chat_send_player(playerName, chat_prefix .. "Someone else plays black pieces!")
 138                         return 0
 139                 end
 140                 if lastMove ~= "" and lastMove ~= "white" then
 141                         return 0
 142                 end
 143                 if pieceTo:find("black") then
 144                         -- Don't replace pieces of same color
 145                         return 0
 146                 end
 147                 playerBlack = playerName
 148                 thisMove = "black"
 149         end
 150
 151         -- DETERMINISTIC MOVING
 152
 153         local from_x, from_y = index_to_xy(from_index)
 154         local to_x, to_y = index_to_xy(to_index)
 155
 156         if pieceFrom:sub(11,14) == "pawn" then
 157                 if thisMove == "white" then
 158                         local pawnWhiteMove = inv:get_stack(from_list, xy_to_index(from_x, from_y - 1)):get_name()
 159                         -- white pawns can go up only
 160                         if from_y - 1 == to_y then
 161                                 if from_x == to_x then
 162                                         if pieceTo ~= "" then
 163                                                 return 0
 164                                         elseif to_index >= 1 and to_index <= 8 then
 165                                                 inv:set_stack(from_list, from_index, "realchess:queen_white")
 166                                         end
 167                                 elseif from_x - 1 == to_x or from_x + 1 == to_x then
 168                                         if not pieceTo:find("black") then
 169                                                 return 0
 170                                         elseif to_index >= 1 and to_index <= 8 then
 171                                                 inv:set_stack(from_list, from_index, "realchess:queen_white")
 172                                         end
 173                                 else
 174                                         return 0
 175                                 end
 176                         elseif from_y - 2 == to_y then
 177                                 if pieceTo ~= "" or from_y < 6 or pawnWhiteMove ~= "" then
 178                                         return 0
 179                                 end
 180                         else
 181                                 return 0
 182                         end
 183
 184                         -- if x not changed,
 185                         --   ensure that destination cell is empty
 186                         -- elseif x changed one unit left or right
 187                         --   ensure the pawn is killing opponent piece
 188                         -- else
 189                         --   move is not legal - abort
 190
 191                         if from_x == to_x then
 192                                 if pieceTo ~= "" then
 193                                         return 0
 194                                 end
 195                         elseif from_x - 1 == to_x or from_x + 1 == to_x then
 196                                 if not pieceTo:find("black") then
 197                                         return 0
 198                                 end
 199                         else
 200                                 return 0
 201                         end
 202
 203                 elseif thisMove == "black" then
 204                         local pawnBlackMove = inv:get_stack(from_list, xy_to_index(from_x, from_y + 1)):get_name()
 205                         -- black pawns can go down only
 206                         if from_y + 1 == to_y then
 207                                 if from_x == to_x then
 208                                         if pieceTo ~= "" then
 209                                                 return 0
 210                                         elseif to_index >= 57 and to_index <= 64 then
 211                                                 inv:set_stack(from_list, from_index, "realchess:queen_black")
 212                                         end
 213                                 elseif from_x - 1 == to_x or from_x + 1 == to_x then
 214                                         if not pieceTo:find("white") then
 215                                                 return 0
 216                                         elseif to_index >= 57 and to_index <= 64 then
 217                                                 inv:set_stack(from_list, from_index, "realchess:queen_black")
 218                                         end
 219                                 else
 220                                         return 0
 221                                 end
 222                         elseif from_y + 2 == to_y then
 223                                 if pieceTo ~= "" or from_y > 1 or pawnBlackMove ~= "" then
 224                                         return 0
 225                                 end
 226                         else
 227                                 return 0
 228                         end
 229
 230                         -- if x not changed,
 231                         --   ensure that destination cell is empty
 232                         -- elseif x changed one unit left or right
 233                         --   ensure the pawn is killing opponent piece
 234                         -- else
 235                         --   move is not legal - abort
 236
 237                         if from_x == to_x then
 238                                 if pieceTo ~= "" then
 239                                         return 0
 240                                 end
 241                         elseif from_x - 1 == to_x or from_x + 1 == to_x then
 242                                 if not pieceTo:find("white") then
 243                                         return 0
 244                                 end
 245                         else
 246                                 return 0
 247                         end
 248                 else
 249                         return 0
 250                 end
 251
 252         elseif pieceFrom:sub(11,14) == "rook" then
 253                 if from_x == to_x then
 254                         -- moving vertically
 255                         if from_y < to_y then
 256                                 -- moving down
 257                                 -- ensure that no piece disturbs the way
 258                                 for i = from_y + 1, to_y - 1 do
 259                                         if inv:get_stack(from_list, xy_to_index(from_x, i)):get_name() ~= "" then
 260                                                 return 0
 261                                         end
 262                                 end
 263                         else
 264                                 -- mocing up
 265                                 -- ensure that no piece disturbs the way
 266                                 for i = to_y + 1, from_y - 1 do
 267                                         if inv:get_stack(from_list, xy_to_index(from_x, i)):get_name() ~= "" then
 268                                                 return 0
 269                                         end
 270                                 end
 271                         end
 272                 elseif from_y == to_y then
 273                         -- mocing horizontally
 274                         if from_x < to_x then
 275                                 -- mocing right
 276                                 -- ensure that no piece disturbs the way
 277                                 for i = from_x + 1, to_x - 1 do
 278                                         if inv:get_stack(from_list, xy_to_index(i, from_y)):get_name() ~= "" then
 279                                                 return 0
 280                                         end
 281                                 end
 282                         else
 283                                 -- mocing left
 284                                 -- ensure that no piece disturbs the way
 285                                 for i = to_x + 1, from_x - 1 do
 286                                         if inv:get_stack(from_list, xy_to_index(i, from_y)):get_name() ~= "" then
 287                                                 return 0
 288                                         end
 289                                 end
 290                         end
 291                 else
 292                         -- attempt to move arbitrarily -> abort
 293                         return 0
 294                 end
 295
 296                 if thisMove == "white" or thisMove == "black" then
 297                         if pieceFrom:sub(-1) == "1" then
 298                                 meta:set_int("castlingWhiteL", 0)
 299                         elseif pieceFrom:sub(-1) == "2" then
 300                                 meta:set_int("castlingWhiteR", 0)
 301                         end
 302                 end
 303
 304         elseif pieceFrom:sub(11,16) == "knight" then
 305                 -- get relative pos
 306                 local dx = from_x - to_x
 307                 local dy = from_y - to_y
 308
 309                 -- get absolute values
 310                 if dx < 0 then dx = -dx end
 311                 if dy < 0 then dy = -dy end
 312
 313                 -- sort x and y
 314                 if dx > dy then dx, dy = dy, dx end
 315
 316                 -- ensure that dx == 1 and dy == 2
 317                 if dx ~= 1 or dy ~= 2 then
 318                         return 0
 319                 end
 320                 -- just ensure that destination cell does not contain friend piece
 321                 -- ^ it was done already thus everything ok
 322
 323         elseif pieceFrom:sub(11,16) == "bishop" then
 324                 -- get relative pos
 325                 local dx = from_x - to_x
 326                 local dy = from_y - to_y
 327
 328                 -- get absolute values
 329                 if dx < 0 then dx = -dx end
 330                 if dy < 0 then dy = -dy end
 331
 332                 -- ensure dx and dy are equal
 333                 if dx ~= dy then return 0 end
 334
 335                 if from_x < to_x then
 336                         if from_y < to_y then
 337                                 -- moving right-down
 338                                 -- ensure that no piece disturbs the way
 339                                 for i = 1, dx - 1 do
 340                                         if inv:get_stack(from_list, xy_to_index(from_x + i, from_y + i)):get_name() ~= "" then
 341                                                 return 0
 342                                         end
 343                                 end
 344                         else
 345                                 -- moving right-up
 346                                 -- ensure that no piece disturbs the way
 347                                 for i = 1, dx - 1 do
 348                                         if inv:get_stack(from_list, xy_to_index(from_x + i, from_y - i)):get_name() ~= "" then
 349                                                 return 0
 350                                         end
 351                                 end
 352                         end
 353                 else
 354                         if from_y < to_y then
 355                                 -- moving left-down
 356                                 -- ensure that no piece disturbs the way
 357                                 for i = 1, dx - 1 do
 358                                         if inv:get_stack(from_list, xy_to_index(from_x - i, from_y + i)):get_name() ~= "" then
 359                                                 return 0
 360                                         end
 361                                 end
 362                         else
 363                                 -- moving left-up
 364                                 -- ensure that no piece disturbs the way
 365                                 for i = 1, dx - 1 do
 366                                         if inv:get_stack(from_list, xy_to_index(from_x - i, from_y - i)):get_name() ~= "" then
 367                                                 return 0
 368                                         end
 369                                 end
 370                         end
 371                 end
 372
 373         elseif pieceFrom:sub(11,15) == "queen" then
 374                 local dx = from_x - to_x
 375                 local dy = from_y - to_y
 376
 377                 -- get absolute values
 378                 if dx < 0 then dx = -dx end
 379                 if dy < 0 then dy = -dy end
 380
 381                 -- ensure valid relative move
 382                 if dx ~= 0 and dy ~= 0 and dx ~= dy then
 383                         return 0
 384                 end
 385
 386                 if from_x == to_x then
 387                         if from_y < to_y then
 388                                 -- goes down
 389                                 -- ensure that no piece disturbs the way
 390                                 for i = 1, dx - 1 do
 391                                         if inv:get_stack(from_list, xy_to_index(from_x, from_y + i)):get_name() ~= "" then
 392                                                 return 0
 393                                         end
 394                                 end
 395                         else
 396                                 -- goes up
 397                                 -- ensure that no piece disturbs the way
 398                                 for i = 1, dx - 1 do
 399                                         if inv:get_stack(from_list, xy_to_index(from_x, from_y - i)):get_name() ~= "" then
 400                                                 return 0
 401                                         end
 402                                 end
 403                         end
 404                 elseif from_x < to_x then
 405                         if from_y == to_y then
 406                                 -- goes right
 407                                 -- ensure that no piece disturbs the way
 408                                 for i = 1, dx - 1 do
 409                                         if inv:get_stack(from_list, xy_to_index(from_x + i, from_y)):get_name() ~= "" then
 410                                                 return 0
 411                                         end
 412                                 end
 413                         elseif from_y < to_y then
 414                                 -- goes right-down
 415                                 -- ensure that no piece disturbs the way
 416                                 for i = 1, dx - 1 do
 417                                         if inv:get_stack(from_list, xy_to_index(from_x + i, from_y + i)):get_name() ~= "" then
 418                                                 return 0
 419                                         end
 420                                 end
 421                         else
 422                                 -- goes right-up
 423                                 -- ensure that no piece disturbs the way
 424                                 for i = 1, dx - 1 do
 425                                         if inv:get_stack(from_list, xy_to_index(from_x + i, from_y - i)):get_name() ~= "" then
 426                                                 return 0
 427                                         end
 428                                 end
 429                         end
 430                 else
 431                         if from_y == to_y then
 432                                 -- goes left
 433                                 -- ensure that no piece disturbs the way and destination cell does
 434                                 for i = 1, dx - 1 do
 435                                         if inv:get_stack(from_list, xy_to_index(from_x - i, from_y)):get_name() ~= "" then
 436                                                 return 0
 437                                         end
 438                                 end
 439                         elseif from_y < to_y then
 440                                 -- goes left-down
 441                                 -- ensure that no piece disturbs the way
 442                                 for i = 1, dx - 1 do
 443                                         if inv:get_stack(from_list, xy_to_index(from_x - i, from_y + i)):get_name() ~= "" then
 444                                                 return 0
 445                                         end
 446                                 end
 447                         else
 448                                 -- goes left-up
 449                                 -- ensure that no piece disturbs the way
 450                                 for i = 1, dx - 1 do
 451                                         if inv:get_stack(from_list, xy_to_index(from_x - i, from_y - i)):get_name() ~= "" then
 452                                                 return 0
 453                                         end
 454                                 end
 455                         end
 456                 end
 457
 458         elseif pieceFrom:sub(11,14) == "king" then
 459                 local dx = from_x - to_x
 460                 local dy = from_y - to_y
 461                 local check = true
 462
 463                 if thisMove == "white" then
 464                         if from_y == 7 and to_y == 7 then
 465                                 if to_x == 1 then
 466                                         local castlingWhiteL = meta:get_int("castlingWhiteL")
 467                                         local idx57 = inv:get_stack(from_list, 57):get_name()
 468
 469                                         if castlingWhiteL == 1 and idx57 == "realchess:rook_white_1" then
 470                                                 for i = 58, from_index - 1 do
 471                                                         if inv:get_stack(from_list, i):get_name() ~= "" then
 472                                                                 return 0
 473                                                         end
 474                                                 end
 475                                                 inv:set_stack(from_list, 57, "")
 476                                                 inv:set_stack(from_list, 59, "realchess:rook_white_1")
 477                                                 check = false
 478                                         end
 479                                 elseif to_x == 6 then
 480                                         local castlingWhiteR = meta:get_int("castlingWhiteR")
 481                                         local idx64 = inv:get_stack(from_list, 64):get_name()
 482
 483                                         if castlingWhiteR == 1 and idx64 == "realchess:rook_white_2" then
 484                                                 for i = from_index + 1, 63 do
 485                                                         if inv:get_stack(from_list, i):get_name() ~= "" then
 486                                                                 return 0
 487                                                         end
 488                                                 end
 489                                                 inv:set_stack(from_list, 62, "realchess:rook_white_2")
 490                                                 inv:set_stack(from_list, 64, "")
 491                                                 check = false
 492                                         end
 493                                 end
 494                         end
 495                 elseif thisMove == "black" then
 496                         if from_y == 0 and to_y == 0 then
 497                                 if to_x == 1 then
 498                                         local castlingBlackL = meta:get_int("castlingBlackL")
 499                                         local idx1 = inv:get_stack(from_list, 1):get_name()
 500
 501                                         if castlingBlackL == 1 and idx1 == "realchess:rook_black_1" then
 502                                                 for i = 2, from_index - 1 do
 503                                                         if inv:get_stack(from_list, i):get_name() ~= "" then
 504                                                                 return 0
 505                                                         end
 506                                                 end
 507                                                 inv:set_stack(from_list, 1, "")
 508                                                 inv:set_stack(from_list, 3, "realchess:rook_black_1")
 509                                                 check = false
 510                                         end
 511                                 elseif to_x == 6 then
 512                                         local castlingBlackR = meta:get_int("castlingBlackR")
 513                                         local idx8 = inv:get_stack(from_list, 1):get_name()
 514
 515                                         if castlingBlackR == 1 and idx8 == "realchess:rook_black_2" then
 516                                                 for i = from_index + 1, 7 do
 517                                                         if inv:get_stack(from_list, i):get_name() ~= "" then
 518                                                                 return 0
 519                                                         end
 520                                                 end
 521                                                 inv:set_stack(from_list, 6, "realchess:rook_black_2")
 522                                                 inv:set_stack(from_list, 8, "")
 523                                                 check = false
 524                                         end
 525                                 end
 526                         end
 527                 end
 528
 529                 if check then
 530                         if dx < 0 then dx = -dx end
 531                         if dy < 0 then dy = -dy end
 532                         if dx > 1 or dy > 1 then return 0 end
 533                 end
 534
 535                 if thisMove == "white" then
 536                         meta:set_int("castlingWhiteL", 0)
 537                         meta:set_int("castlingWhiteR", 0)
 538                 elseif thisMove == "black" then
 539                         meta:set_int("castlingBlackL", 0)
 540                         meta:set_int("castlingBlackR", 0)
 541                 end
 542         end
 543
 544         meta:set_string("playerWhite", playerWhite)
 545         meta:set_string("playerBlack", playerBlack)
 546         lastMove = thisMove
 547         meta:set_string("lastMove", lastMove)
 548         meta:set_int("lastMoveTime", minetest.get_gametime())
 549
 550         if pieceTo:sub(11,14) == "king" then
 551                 meta:set_string("winner", thisMove)
 552         end
 553
 554         local moves = meta:get_string("moves")
 555         local pieceFrom_s = pieceFrom:match(":(%w+_%w+)")
 556         local pieceFrom_si_id = pieces_str:match("(%d+)=" .. pieceFrom_s)
 557         local pieceTo_s = pieceTo_s ~= "" and pieceTo:match(":(%w+_%w+)") or ""
 558         local pieceTo_si_id = pieceTo_s ~= "" and pieces_str:match("(%d+)=" .. pieceTo_s) or ""
 559
 560         moves = pieceFrom_si_id .. "," ..
 561                 letters[from_x + 1] .. (from_y + 1) .. "," ..
 562                         (pieceTo ~= "" and "#33FF33" or "#FFFFFF") .. ", > ,#FFFFFF," ..
 563                 letters[to_x + 1] .. (to_y + 1) .. "," ..
 564                 (pieceTo ~= "" and pieceTo_si_id or "69") .. "," ..
 565                 moves
 566
 567         meta:set_string("moves", moves)
 568
 569         local eaten = meta:get_string("eaten")
 570         if pieceTo ~= "" then
 571                 eaten = eaten .. pieceTo_s .. ","
 572         end
 573
 574         meta:set_string("eaten", eaten)
 575
 576         local eaten_t = string.split(eaten, ",")
 577         local eaten_img = ""
 578
 579         local a, b = 0, 0
 580         for i = 1, #eaten_t do
 581                 local is_white = eaten_t[i]:sub(-5,-1) == "white"
 582                 local X = (is_white and a or b) % 4
 583                 local Y = ((is_white and a or b) % 16 - X) / 4
 584
 585                 if is_white then
 586                         a = a + 1
 587                 else
 588                         b = b + 1
 589                 end
 590
 591                 eaten_img = eaten_img ..
 592                         "image[" .. ((X + (is_white and 11.7 or 8.8)) - (X * 0.45)) .. "," ..
 593                                     ((Y + 5.56) - (Y * 0.2)) .. ";1,1;" .. eaten_t[i] .. ".png]"
 594         end
 595
 596         local black_win = lastMove == "black" and pieceTo:sub(11,14) == "king"
 597         local white_win = lastMove == "white" and pieceTo:sub(11,14) == "king"
 598
 599         local formspec = fs ..
 600                 "label[2,0.3;" .. (black_win and
 601                                    minetest.colorize("#00FF00", playerBlack .. " has win") or
 602                                    minetest.colorize("#000001",
 603                                         (lastMove == "white" and playerBlack ~= "" and not white_win) and
 604                                          playerBlack .. "..." or playerBlack)) .. "]" ..
 605                 "label[2,9.15;" .. (white_win and
 606                                     minetest.colorize("#00FF00", playerWhite .. " has win") or
 607                                     minetest.colorize("#000001",
 608                                         (lastMove == "black" and playerWhite ~= "" and not black_win) and
 609                                          playerWhite .. "..." or playerWhite)) .. "]" ..
 610                 "table[8.9,1.05;5.07,3.75;moves;" .. moves:sub(1,-2) .. ";1]" ..
 611                 eaten_img
 612
 613         meta:set_string("formspec", formspec)
 614
 615         return 1
 616 end
 617
 618 local function timeout_format(timeout_limit)
 619         local time_remaining = timeout_limit - minetest.get_gametime()
 620         local minutes = math.floor(time_remaining / 60)
 621         local seconds = time_remaining % 60
 622
 623         if minutes == 0 then
 624                 return seconds .. " sec."
 625         end
 626
 627         return minutes .. " min. " .. seconds .. " sec."
 628 end
 629
 630 function realchess.fields(pos, _, fields, sender)
 631         local playerName = sender:get_player_name()
 632         local meta = minetest.get_meta(pos)
 633         local timeout_limit = meta:get_int("lastMoveTime") + 300
 634         local playerWhite = meta:get_string("playerWhite")
 635         local playerBlack = meta:get_string("playerBlack")
 636         local lastMoveTime = meta:get_int("lastMoveTime")
 637         if fields.quit then return end
 638
 639         -- timeout is 5 min. by default for resetting the game (non-players only)
 640         if fields.new then
 641                 if (playerWhite == playerName or playerBlack == playerName) then
 642                         realchess.init(pos)
 643                 else
 644                         minetest.chat_send_player(playerName, chat_prefix ..
 645                                 "You can't reset the chessboard, a game has been started.\n" ..
 646                                 "If you are not a current player, try again in " ..
 647                                         timeout_format(timeout_limit))
 648                 end
 649         end
 650
 651         if fields.new and lastMoveTime ~= 0 and minetest.get_gametime() >= timeout_limit and
 652                         (playerWhite ~= playerName or playerBlack ~= playerName) then
 653                 realchess.init(pos)
 654         end
 655 end
 656
 657 function realchess.dig(pos, player)
 658         if not player then
 659                 return false
 660         end
 661
 662         local meta = minetest.get_meta(pos)
 663         local playerName = player:get_player_name()
 664         local timeout_limit = meta:get_int("lastMoveTime") + 300
 665         local lastMoveTime = meta:get_int("lastMoveTime")
 666
 667         -- timeout is 5 min. by default for digging the chessboard (non-players only)
 668         return (lastMoveTime == 0 and minetest.get_gametime() > timeout_limit) or
 669                 minetest.chat_send_player(playerName, chat_prefix ..
 670                                 "You can't dig the chessboard, a game has been started.\n" ..
 671                                 "Reset it first if you're a current player, or dig it again in " ..
 672                                 timeout_format(timeout_limit))
 673 end
 674
 675 function realchess.on_move(pos, from_list, from_index)
 676         local inv = minetest.get_meta(pos):get_inventory()
 677         inv:set_stack(from_list, from_index, '')
 678         return false
 679 end
 680
 681 minetest.register_node(":realchess:chessboard", {
 682         description = "Chess Board",
 683         drawtype = "nodebox",
 684         paramtype = "light",
 685         paramtype2 = "facedir",
 686         inventory_image = "chessboard_top.png",
 687         wield_image = "chessboard_top.png",
 688         tiles = {"chessboard_top.png", "chessboard_top.png", "chessboard_sides.png"},
 689         groups = {choppy=3, oddly_breakable_by_hand=2, flammable=3},
 690         sounds = default.node_sound_wood_defaults(),
 691         node_box = {type = "fixed", fixed = {-.375, -.5, -.375, .375, -.4375, .375}},
 692         sunlight_propagates = true,
 693         on_rotate = screwdriver.rotate_simple,
 694         can_dig = realchess.dig,
 695         on_construct = realchess.init,
 696         on_receive_fields = realchess.fields,
 697         allow_metadata_inventory_move = realchess.move,
 698         on_metadata_inventory_move = realchess.on_move,
 699         allow_metadata_inventory_take = function() return 0 end
 700 })
 701
 702 local function register_piece(name, count)
 703         for _, color in pairs({"black", "white"}) do
 704         if not count then
 705                 minetest.register_craftitem(":realchess:" .. name .. "_" .. color, {
 706                         description = color:gsub("^%l", string.upper) .. " " .. name:gsub("^%l", string.upper),
 707                         inventory_image = name .. "_" .. color .. ".png",
 708                         stack_max = 1,
 709                         groups = {not_in_creative_inventory=1}
 710                 })
 711         else
 712                 for i = 1, count do
 713                         minetest.register_craftitem(":realchess:" .. name .. "_" .. color .. "_" .. i, {
 714                                 description = color:gsub("^%l", string.upper) .. " " .. name:gsub("^%l", string.upper),
 715                                 inventory_image = name .. "_" .. color .. ".png",
 716                                 stack_max = 1,
 717                                 groups = {not_in_creative_inventory=1}
 718                         })
 719                 end
 720         end
 721         end
 722 end
 723
 724 register_piece("pawn", 8)
 725 register_piece("rook", 2)
 726 register_piece("knight", 2)
 727 register_piece("bishop", 2)
 728 register_piece("queen")
 729 register_piece("king")
 730
 731 -- Recipes
 732
 733 minetest.register_craft({
 734         output = "realchess:chessboard",
 735         recipe = {
 736                 {"dye:black", "dye:white", "dye:black"},
 737                 {"stairs:slab_wood", "stairs:slab_wood", "stairs:slab_wood"}
 738         }
 739 })