-- This module implements {{aligned table}}
local p = {}

local function isnotempty(s)
	return s and s:match( '^%s*(.-)%s*$' ) ~= ''
end

function p.table(frame)
	local args = (frame.args[3] ~= nil) and frame.args or frame:getParent().args
	local entries = {}
	local colclass = {}
	local colstyle = {}
	local cols = tonumber(args['cols']) or 2

	-- create the root table
	local root = mw.html.create('table')

	-- add table style for fullwidth
	if isnotempty(args['fullwidth']) then
		root
			:css('width', '100%')
			:css('border-collapse', 'collapse')
			:css('border-spacing', '0px 0px')
			:css('border', 'none')
	end

	-- add table classes
	if isnotempty(args['class']) then
		root:addClass(args['class'])
	end

	-- add table style
	if isnotempty(args['style']) then
		root:cssText(args['style'])
	end

	-- build arrays with the column styles and classes
	if isnotempty(args['leftright']) then
		colstyle[1] = 'text-align:left;'
		colstyle[2] = 'text-align:right;'
	end
	if isnotempty(args['rightleft']) then
		colstyle[1] = 'text-align:right;'
		colstyle[2] = 'text-align:left;'
	end
	for i = 1,cols do
		colclass[ i ] = colclass[ i ] or ''
		colstyle[ i ] = colstyle[ i ] or ''
		if isnotempty(args['colstyle']) then
			colstyle[ i ] = args['colstyle'] .. ';' .. colstyle[ i ]
		end
		if isnotempty(args['colalign' .. tostring(i)]) then
			colstyle[ i ] = 'text-align:' .. args['colalign' .. tostring(i)] .. ';' .. colstyle[ i ]
		elseif isnotempty(args['col' .. tostring(i) .. 'align']) then
			colstyle[ i ] = 'text-align:' .. args['col' .. tostring(i) .. 'align'] .. ';' .. colstyle[ i ]
		elseif isnotempty(args['align' .. tostring(i)]) then
			colstyle[ i ] = 'text-align:' .. args['align' .. tostring(i)] .. ';' .. colstyle[ i ]
		end
		if isnotempty(args['colnowrap' .. tostring(i)]) then
			colstyle[ i ] = 'white-space:nowrap;' .. colstyle[ i ]
		elseif isnotempty(args['col' .. tostring(i) .. 'nowrap']) then
			colstyle[ i ] = 'white-space:nowrap;' .. colstyle[ i ]
		elseif isnotempty(args['nowrap' .. tostring(i)]) then
			colstyle[ i ] = 'white-space:nowrap;' .. colstyle[ i ]
		end
		if isnotempty(args['colwidth' .. tostring(i)]) then
			colstyle[ i ] = 'width:' .. args['colwidth' .. tostring(i)] .. ';' .. colstyle[ i ]
		elseif isnotempty(args['col' .. tostring(i) .. 'width']) then
			colstyle[ i ] = 'width:' .. args['col' .. tostring(i) .. 'width'] .. ';' .. colstyle[ i ]
		elseif isnotempty(args['colwidth']) then
			colstyle[ i ] = 'width:' .. args['colwidth'] .. ';' .. colstyle[ i ]
		end
		if isnotempty(args['colstyle' .. tostring(i)]) then
			colstyle[ i ] = colstyle[ i ] .. args['colstyle' .. tostring(i)]
		elseif isnotempty(args['col' .. tostring(i) .. 'style']) then
			colstyle[ i ] = colstyle[ i ] .. args['col' .. tostring(i) .. 'style']
		elseif isnotempty(args['style' .. tostring(i)]) then
			colstyle[ i ] = colstyle[ i ] .. args['style' .. tostring(i)]
		end
		if isnotempty(args['colclass' .. tostring(i)]) then
			colclass[ i ] =  args['colclass' .. tostring(i)]
		elseif isnotempty(args['col' .. tostring(i) .. 'class']) then
			colclass[ i ] =  args['col' .. tostring(i) .. 'class']
		elseif isnotempty(args['class' .. tostring(i)]) then
			colclass[ i ] =  args['class' .. tostring(i)]
		end
	end
	-- compute the maximum cell index
	local cellcount = 0
	for k, v in pairs( args ) do
		if type( k ) == 'number' then
			cellcount = math.max(cellcount, k)
		end
	end
	-- compute the number of rows
	local rows = math.ceil(cellcount / cols)

	-- build the table content
	if isnotempty(args['title']) then
		local caption = root:tag('caption')
		caption:cssText(args['titlestyle'])
		caption:wikitext(args['title'])
	end
	if isnotempty(args['above']) then
		local row = root:tag('tr')
		local cell = row:tag('th')
		cell:attr('colspan', cols)
		cell:cssText(args['abovestyle'])
		cell:wikitext(args['above'])
	end
	for j=1,rows do
		-- start a new row
		local row = root:tag('tr')
		if isnotempty(args['rowstyle']) then
			row:cssText(args['rowstyle'])
		else
			row:css('vertical-align', 'top')
		end
		if isnotempty(args['rowclass']) then
			row:addClass(args['rowclass'])
		end
		-- loop over the cells in the row
		for i=1,cols do
			local cell
			if isnotempty(args['row' .. tostring(j) .. 'header']) then
				cell = row:tag('th'):attr('scope','col')
			elseif isnotempty(args['col' .. tostring(i) .. 'header']) then
				cell = row:tag('th'):attr('scope','row')
			else
				cell = row:tag('td')
			end
			if args['class' .. tostring(j) .. '.' .. tostring(i)] then
				cell:addClass(args['class' .. tostring(j) .. '.' .. tostring(i)])
			else
				if args['rowclass' .. tostring(j)] then
					cell:addClass(args['rowclass' .. tostring(j)])
				elseif args['row' .. tostring(j) .. 'class'] then
					cell:addClass(args['row' .. tostring(j) .. 'class'])
				elseif args['rowevenclass'] and math.fmod(j,2) == 0 then
					cell:addClass(args['rowevenclass'])
				elseif args['rowoddclass'] and math.fmod(j,2) == 1 then	
					cell:addClass(args['rowoddclass'])
				end
				if colclass[i] ~= '' then
					cell:addClass(colclass[i])
				end
			end
			if args['style' .. tostring(j) .. '.' .. tostring(i)] then
				cell:cssText(args['style' .. tostring(j) .. '.' .. tostring(i)])
			else
				if args['rowstyle' .. tostring(j)] then
					cell:cssText(args['rowstyle' .. tostring(j)])
				elseif args['rowevenstyle'] and math.fmod(j,2) == 0 then
					cell:cssText(args['rowevenstyle'])
				elseif args['rowoddstyle'] and math.fmod(j,2) == 1 then	
					cell:cssText(args['rowoddstyle'])
				elseif args['row' .. tostring(j) .. 'style'] then
					cell:cssText(args['row' .. tostring(j) .. 'style'])
				end
				if isnotempty(colstyle[i]) then
					cell:cssText(colstyle[i])
				end
			end
			cell:wikitext(mw.ustring.gsub(args[cols*(j - 1) + i] or '', '^(.-)%s*$', '%1') or '')
		end
	end
	-- return the root table
	return tostring(root)
end

return p