local p = {} function chessboard(args, size, rev, letters, numbers, header, footer, align, clear) function image_square( pc, row, col, size ) local colornames = { l = 'white', d = 'black' } local piecenames = { p = 'pawn', r = 'rook', n = 'knight', b = 'bishop', q = 'queen', k = 'king', a = 'archbishop', c = 'chancelor', z = 'champion', w = 'wizard', t = 'fool', h = 'upside-down pawn', m = 'upside-down rook', s = 'upside-down knight', f = 'upside-down king', e = 'upside-down bishop', g = 'upside-down queen', } local symnames = { xx = 'black cross', ox = 'white cross', xo = 'black circle', oo = 'white circle', ul = 'up-left arrow', ua = 'up arrow', ur = 'up-right arrow', la = 'left arrow', ra = 'right arrow', dl = 'down-left arrow', da = 'down arrow', dr = 'down-right arrow', lr = 'left-right arrow', ud = 'up-down arrow', x0 = 'zero', x1 = 'one', x2 = 'two', x3 = 'three', x4 = 'four', x5 = 'five', x6 = 'six', x7 = 'seven', x8 = 'eight', x9 = 'nine', }  function colchar( col ) return ( 'abcdefgh' ):sub( col, col ) end  local color = mw.ustring.gsub( pc, '^.*(%w)(%w).*$', '%2' ) or '' local piece = mw.ustring.gsub( pc, '^.*(%w)(%w).*$', '%1' ) or '' local alt = colchar( col ) .. row .. ' ' if colornames[color] and piecenames[piece] then alt = alt .. colornames[color] .. ' ' .. piecenames[piece] else alt = alt .. ( symnames[piece .. color] or piece .. ' ' .. color ) end  return string.format( '[[File:Chess %s%st45.svg|%dx%dpx|alt=%s|%s]]', piece, color, size, size, alt, alt ) end  function letters_row( rev, num_lt, num_rt ) local td = '<td style="height:18px;width:' .. size .. 'px;">' local legends = 'abcdefgh' local l = mw.text.split( rev and legends:reverse() or legends, '' ) return '<tr style="vertical-align:middle">\n' .. ( num_lt and '<td></td>' or '' ) .. td .. table.concat( l, '</td>' .. td ) .. '</td>' .. ( num_rt and '<td></td>' or '' ) .. '\n</tr>' end local letters_tp = letters:match( 'both' ) or letters:match( 'top' ) local letters_bt = letters:match( 'both' ) or letters:match( 'bottom' ) local numbers_lt = numbers:match( 'both' ) or numbers:match( 'left' ) local numbers_rt = numbers:match( 'both' ) or numbers:match( 'right' ) local width = 8 * size + 2 if ( numbers_lt ) then width = width + 18 end if ( numbers_rt ) then width = width + 18 end  local b = '' local caption = ''  if ( letters_tp ) then b = b .. letters_row( rev, numbers_lt, numbers_rt ) .. '\n' end b = b .. '<tr style="vertical-align:middle">' if ( numbers_lt ) then b = b .. '<td style="width:18px;height:' .. size .. 'px">' .. (rev and 1 or 8) .. '</td>' end b = b .. '<td colspan=8 rowspan=8><div class="chess-board" style="position:relative;">' b = b .. string.format( '[[File:Chessboard480.png|%dx%dpx|link=]]', 8 * size, 8 * size ) for trow = 1,8 do local row = rev and trow or ( 9 - trow ) for tcol = 1,8 do local col = rev and ( 9 - tcol ) or tcol local piece = args[8 * ( 8 - row ) + col + 2] or '' if piece:match( '%w%w' ) then local img = image_square(piece:match('%w%w'), row, col, size ) b = b .. string.format( '<div style="position:absolute;z-index:3;top:%dpx;left:%dpx;">%s</div>\n', ( trow - 1 ) * size, ( tcol - 1 ) * size, img ) end end end b = b .. '</div></td>' if ( numbers_rt ) then b = b .. '<td style="width:18px;height:' .. size ..'px">' .. (rev and 1 or 8) .. '</td>' end if ( numbers_lt or numbers_rt ) then for trow = 2, 8 do local row = rev and trow or ( 9 - trow ) b = b .. '<tr style="vertical-align:middle">' if ( numbers_lt ) then b = b .. '<td style="height:' .. size .. 'px">' .. row .. '</td>' end if ( numbers_rt ) then b = b .. '<td style="height:' .. size .. 'px">' .. row .. '</td>' end b = b .. '</tr>\n' end end if ( letters_bt ) then b = b .. letters_row( rev, numbers_lt, numbers_rt ) .. '\n' end  if footer:match( '^%s*$' ) then else caption = '<div class="thumbcaption">' .. footer .. '</div>\n' end  return '<div class="thumb ' .. align .. '" style="clear:' .. clear .. '; text-align:center;">' .. header .. '\n<div class="thumbinner" style="width:' .. width .. 'px;">\n' .. '<table cellpadding=0 cellspacing=0 style="background:white; font-size:88%; border:1px #b0b0b0 solid; padding:0; ' .. 'margin:auto;">\n' .. b .. '\n</table>\n' .. caption .. '</div></div>'end function convertFenToArgs( fen ) -- converts FEN notation to 64 entry array of positions, offset by 2 local res = { ' ', ' ' } -- Loop over rows, which are delimited by / for srow in string.gmatch( "/" .. fen, "/%w+" ) do -- Loop over all letters and numbers in the row for piece in srow:gmatch( "%w" ) do if piece:match( "%d" ) then -- if a digit for k=1,piece do table.insert(res,' ') end else -- not a digit local color = piece:match( '%u' ) and 'l' or 'd' piece = piece:lower() table.insert( res, piece .. color ) end end end  return resend function convertArgsToFen( args, offset ) function nullOrWhitespace( s ) return not s or s:match( '^%s*(.-)%s*$' ) == '' end function piece( s ) return nullOrWhitespace( s ) and 1 or s:gsub( '%s*(%a)(%a)%s*', function( a, b ) return b == 'l' and a:upper() or a end ) end  local res = '' offset = offset or 0 for row = 1, 8 do for file = 1, 8 do res = res .. piece( args[8*(row - 1) + file + offset] ) end if row < 8 then res = res .. '/' end end return mw.ustring.gsub(res, '1+', function( s ) return #s end )end function p.board(frame) local args = frame.args local pargs = frame:getParent().args local size = args.size or pargs.size or '26' local reverse = ( args.reverse or pargs.reverse or '' ):lower() == "true" local letters = ( args.letters or pargs.letters or 'both' ):lower() local numbers = ( args.numbers or pargs.numbers or 'both' ):lower() local header = args[2] or pargs[2] or '' local footer = args[67] or pargs[67] or '' local align = ( args[1] or pargs[1] or 'tright' ):lower() local clear = args.clear or pargs.clear or ( align:match('tright') and 'right' ) or 'none' local fen = args.fen or pargs.fen  size = mw.ustring.match( size, '[%d]+' ) or '26' -- remove px from size if (fen) then align = args.align or pargs.align or 'tright' clear = args.clear or pargs.clear or ( align:match('tright') and 'right' ) or 'none' header = args.header or pargs.header or '' footer = args.footer or pargs.footer or '' return chessboard( convertFenToArgs( fen ), size, reverse, letters, numbers, header, footer, align, clear ) end if args[3] then return chessboard(args, size, reverse, letters, numbers, header, footer, align, clear) else return chessboard(pargs, size, reverse, letters, numbers, header, footer, align, clear) endend function p.fen2ascii(frame) -- {{#invoke:Chessboard|fen2ascii|fen=...}} local b = convertFenToArgs( frame.args.fen ) local res = '|=\n' local offset = 2 for row = 1,8 do local n = (9 - row) res = res .. n .. ' |' .. table.concat(b, '|', 8*(row-1) + 1 + offset, 8*(row-1) + 8 + offset) .. '|=\n' end res = mw.ustring.gsub( res,'\| \|', '| |' ) res = mw.ustring.gsub( res,'\| \|', '| |' ) res = res .. ' a b c d e f g h' return resend function p.ascii2fen( frame ) -- {{#invoke:Chessboard|ascii2fen|kl| | |....}} return convertArgsToFen( frame.args, frame.args.offset or 1 )end return p