Editing Module:Chessboard/sandbox

local p = {}

local cfg = mw.loadData('Module:Chessboard/configuration')

local function image_square( pc, row, col, size )
	local piece = mw.ustring.gsub( pc, '^.*(%w)(%w).*$', '%1' ) or ''
	local color = mw.ustring.gsub( pc, '^.*(%w)(%w).*$', '%2' ) or ''
	local square = cfg.files[col] .. row
	local message = mw.message.newRawMessage
	local color_name = cfg.color_names[color]
	local piece_name = cfg.piece_names[piece]
	local symbol_name = cfg.symbol_names[piece .. color]
	local alt = ''
	if color_name and piece_name then
		alt = message(
			cfg.alt_with_color_and_piece,
			square,
			color_name,
			piece_name
		):plain()
	elseif symbol_name then
		alt = message(
			cfg.alt_with_symbol,
			square,
			symbol_name
		):plain()
	else
		alt = message(
			cfg.alt_otherwise,
			square,
			piece,
			color
		):plain()
	end

	return string.format(
		'[[File:Chess %s%st45.svg|%dx%dpx|alt=%s|%s|link=|class=notpageimage]]',
		piece, color, size, size, alt, alt
	)

end
	
local function innerboard(args, size, rev)
	local board = mw.html.create('div')
	local board_width = cfg.cols * size
	local board_height = cfg.rows * size
	local size_px = size .. 'px'
	board:addClass('chessboard-board')
		:wikitext(string.format(
			'[[File:%s|%dx%dpx|link=|alt=Empty chess board|class=notpageimage]]',
			cfg.board_image, board_width, board_height
		))
	
	for trow = 1,cfg.rows do
		local row = rev and trow or ( 1 + cfg.rows - trow )
		for tcol = 1,cfg.cols do
			local col = rev and ( 1 + cfg.cols - tcol ) or tcol
			local piece = args[cfg.cols * ( cfg.rows - row ) + col + 2] or ''
			local square = piece:match('%w%w')
			if square then
				local img = image_square(square, row, col, size )
				board:tag('div')
					:css('top', tostring(( trow - 1 ) * size) .. 'px')
					:css('left', tostring(( tcol - 1 ) * size) .. 'px')
					:css('width', size_px)
					:css('height', size_px)
					:wikitext(img)
			end
		end
	end

	return tostring(board)
end

function chessboard(args, size, rev, letters, numbers, header, footer, align, clear)
	function letters_row( rev, num_lt, num_rt )
		
		local files_row = mw.html.create('')
		if num_lt then
			files_row:tag('td')
		end
		for k = 1,cfg.cols do
			files_row:tag('td')
				:css('width', size .. 'px')
				:wikitext(rev and cfg.files[1+cfg.cols-k] or cfg.files[k])
		end
		if num_rt then
			files_row:tag('td')
		end
		return tostring(files_row)
	end
	
	local letters_tp = letters:match( cfg.letters_both ) or letters:match( cfg.letters_top )
	local letters_bt = letters:match( cfg.letters_both ) or letters:match( cfg.letters_bottom )
	local numbers_lt = numbers:match( cfg.numbers_both ) or numbers:match( cfg.numbers_left )
	local numbers_rt = numbers:match( cfg.numbers_both ) or numbers:match( cfg.numbers_right )
	local width = cfg.cols * size + 2
	if ( numbers_lt ) then width = width + 18 end
	if ( numbers_rt ) then width = width + 18 end

	local root = mw.html.create('div')
		:addClass('chessboard')
		:addClass('thumb')
		:addClass(align)
	if header and header ~= '' then
		root:tag('div')
			:addClass('chessboard-header')
			:css('max-width', (width + cfg.cols) .. 'px')
			:wikitext(header)
	end
	local board_wrapper = root:tag('div')
		:addClass('thumbinner chessboard-board-wrapper')
		:css('width', width .. 'px')
	local board_with_notation = board_wrapper:tag('table')
		:addClass('chessboard-board-and-notation')

	if ( letters_tp ) then
		board_with_notation:tag('tr')
			:wikitext(letters_row( rev, numbers_lt, numbers_rt ))
	end
	local tablerow = board_with_notation:tag('tr')
	local size_px = size .. 'px'
	if ( numbers_lt ) then 
		tablerow:tag('td')
			:css('width', '18px')
			:css('height', size_px)
			:wikitext(rev and 1 or cfg.rows) 
	end
	local td = tablerow:tag('td')
		:attr('colspan', cfg.cols)
		:attr('rowspan', cfg.rows)
		:wikitext(innerboard(args, size, rev))
	
	if ( numbers_rt ) then 
		tablerow:tag('td')
			:css('width', '18px')
			:css('height', size_px)
			:wikitext(rev and 1 or cfg.rows) 
	end
	if ( numbers_lt or numbers_rt ) then
		for trow = 2, cfg.rows do
			local idx = rev and trow or ( 1 + cfg.rows - trow )
			tablerow = board_with_notation:tag('tr')
			if ( numbers_lt ) then 
				tablerow:tag('td')
					:css('height', size_px)
					:wikitext(idx)
			end
			if ( numbers_rt ) then 
				tablerow:tag('td')
					:css('height', size_px)
					:wikitext(idx)
			end
		end
	end
	if ( letters_bt ) then
		board_with_notation:tag('tr')
			:addClass('chessboard-letters')
			:wikitext(letters_row( rev, numbers_lt, numbers_rt ))
	end

	if (footer and footer ~= '') then
		board_wrapper:tag('div')
			:addClass('thumbcaption')
			:wikitext(footer)
	end

	return tostring(root)
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 res
end

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, cfg.rows do
		for file = 1, cfg.cols do
			res = res .. piece( args[cfg.cols*(row - 1) + file + offset] )
		end
		if row < cfg.rows 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[cfg.rows*cfg.cols + 3] or pargs[cfg.rows*cfg.cols + 3] 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
	local templatestyles = frame:extensionTag {
		name = 'templatestyles', args = { src = 'Module:Chessboard/styles.css' }
	}
	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 templatestyles .. chessboard( convertFenToArgs( fen ), size, reverse, letters, numbers, header, footer, align, clear )
	end
	if args[3] then
		return templatestyles .. chessboard(args, size, reverse, letters, numbers, header, footer, align, clear)
	else
		return templatestyles .. chessboard(pargs, size, reverse, letters, numbers, header, footer, align, clear)
	end
end

function p.fen2ascii(frame)
	-- {{#invoke:Chessboard|fen2ascii|fen=...}}
	local b = convertFenToArgs( frame.args.fen )
	local res = '|=\n'
	local offset = 2
	for row = 1,cfg.rows do
		local n = (1 + cfg.rows - row)
		res = res .. n .. ' |' .. 
			table.concat(b, '|', cfg.cols*(row-1) + 1 + offset, cfg.cols*row + offset) .. '|=\n'
	end
	res = mw.ustring.gsub( res,'\| \|', '|  |' )
	res = mw.ustring.gsub( res,'\| \|', '|  |' )
	return res .. '   a  b  c  d  e  f  g  h'
end

function p.ascii2fen( frame )
	-- {{#invoke:Chessboard|ascii2fen|kl| | |....}}
	return convertArgsToFen( frame.args, frame.args.offset or 1 )
end

return p