-- This module implements [[Template:Ranking movements]]

local p = {}



local templatestyles = 'Module:Ranking movements/styles.css'



local colors = {

	'+' = '#D8FFEB',

	'-' = '#FFE6E6',

	'not released' = '#999999'

}

local labels = {

	'title' = 'Ranking movements',

	'legend' = 'Legend',

	'week' = 'Week',

	'poll' = 'Poll',

	'pre' = 'Pre',

	'final' = 'Final',

	'not released' = 'Not released',

	'+' = 'Increase in ranking',

	'-' = 'Decrease in ranking',

	'—' = 'Not ranked',

	'RV' = 'Received votes',

	'т' = 'Tied with team above or below',

	'( )' = 'First-place votes'

}



local legend = {

	'+' = false,

	'-' = false,

	'—' = false,

	'RV' = false,

	'т' = false,

	'( )' = false

}



local function format_cell_text(s)

	if s then

		if s:match('^[Nn][Rr]') or s:match('^—') then

			legend'—' = true

		end

		if s:match('^[Rr][Vv]') then

			legend'RV' = true

		end

		if s:match('%d[%-%s]*[Tt]') or s:match('[Tт]') then

			legend'т' = true

		end

		if s:match('[%(%)]') then

			legend'( )' = true

		end

		s = mw.ustring.gsub(s, '^NR', '—')

	end

	return s

end



local function get_rank(s)

	-- This is intended to remove any extra stuff after the ranking

	local result = mw.ustring.match(s or '', '^%d*') or '' -- Is it numbers?

	if result == '' then

		result = mw.ustring.match(s or '', '^[%a/—]*') or '' -- Is it letters?

	end

	return result

end



local function get_color(lastweek, thisweek)

	-- No coloring if first week or this week is blank

	if (lastweek == 'first week') or (thisweek == '') or (lastweek == '')

		or (lastweek == 'N/A') or (thisweek == 'N/A') then

		return nil

	end

	-- No coloring if the rank has not changes

	if (lastweek == thisweek) then

		return nil

	end

	-- If last week was NR then rank has increased

	if (lastweek == 'NR' or lastweek == '—') then

		legend'+' = true

		return colors'+'

	end

	-- If last week was RV

	if (lastweek == 'RV') then

		-- If this week is NR then rank has decreased, otherwise increased

		if (thisweek == 'NR' or thisweek == '—') then

			legend'-' = true

			return colors'-'

		else

			legend'+' = true

			return colors'+'

		end

	end

	-- In all other cases, just compare the numbers

	lastweek = tonumber(lastweek) or 999999

	thisweek = tonumber(thisweek) or 999999

	if (lastweek > thisweek) then

		legend'+' = true

		return colors'+'

	end

	if (thisweek > lastweek) then

		legend'-' = true

		return colors'-'

	end

	return nil

end



local tracking, preview = {}, {}



local function checkargs(args)

    for k, v in pairs(args) do

    	if v ~= '' then

			if k and type(k) == 'string' then

				if k:match('^poll[1-6]firstweek$') or k:match('^poll[1-6]lastweek$') 

					or k:match('^poll[1-6]title$') or k:match('^poll[1-6]_final$') or k == 'title' or k == 'nocat'

					or k:match('^wk1?%d$') or k:match('^wk2[01]') then

					-- valid

				elseif k:match('^poll[1-6]_1?%d$') or k:match('^poll[1-6]_2[01]$') then

					-- valid

					local i = mw.ustring.gsub(k, '^poll([1-6])_%d+$', '%1')

					local j = mw.ustring.gsub(k, '^poll[1-6]_(%d+)$', '%1')

					local maxweeks = tonumber(args'poll' .. i .. 'lastweek']) or 20

					if tonumber(j) > maxweeks then

						table.insert(tracking, '[[Category:Pages using ranking movements with poll after last week|' .. i .. ']]')

					end

				else

					-- invalid

					local vlen = mw.ustring.len(k)

					k = mw.ustring.sub(k, 1, (vlen < 25) and vlen or 25) 

					k = mw.ustring.gsub(k, '[^%w\-_ ]', '?')

					table.insert(tracking, '[[Category:Pages using ranking movements with unknown parameters|' .. k .. ']]')

					table.insert(preview, '"' .. k .. '"')

				end

			end

		end

	end

end





function p.main(frame)

	local args = require('Module:Arguments').getArgs(frame)

	

	local maxpolls = 6

	-- Compute the maximum number of columns

	local minweeks = 20

	local maxweeks = 0

	for k = 1,maxpolls do

		local n = tonumber(args'poll' .. k .. 'lastweek']) or (args'poll' .. k .. 'title' and 20 or 0)

		maxweeks = (n > maxweeks) and n or maxweeks

		local n = tonumber(args'poll' .. k .. 'firstweek']) or (args'poll' .. k .. 'title' and 0 or 20)

		minweeks = (n < minweeks) and n or minweeks

	end



	-- Start table

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

		:addClass('wikitable ranking-movements')



	-- Table caption title

	local caption = root:tag('caption'):wikitext(args'title' or labels'title'])



	-- Week header row

	local row = root:tag('tr')

	row:tag('th') -- Blank space in corner

	row:tag('th'):attr('colspan', maxweeks - minweeks + 1):wikitext(labels'week'])



	-- Poll header row

	row = root:tag('tr')

	row:tag('th')

		:wikitext(labels'poll'])

	for k = minweeks,maxweeks do

		local text = args'wk' .. k or k

		if (k == 0) then

			text = args'wk' .. k or labels'pre'

		elseif (k == maxweeks) then

			text = args'wk' .. k or labels'final'

		end

		row:tag('th')

			:wikitext(text)

	end

	

	-- Poll data rows

	for i = 1,maxpolls do

		local ptitle = args'poll' .. i .. 'title' or ''

		local pfirstweek = tonumber(args'poll' .. i .. 'firstweek']) or 0

		local plastweek = tonumber(args'poll' .. i .. 'lastweek']) or 20

		if ptitle ~= '' then

			row = root:tag('tr')

			row:tag('th')

				:wikitext(ptitle)

			-- Before the first poll

			if pfirstweek > minweeks then

				row:tag('td')

					:attr('colspan', pfirstweek - minweeks)

					:css('background', colors'not released'])

					:wikitext(labels'not released'])

			end

			-- Results

			local lastweek = 'first week'

			for k = pfirstweek,plastweek do

				local rank = args'poll' .. i .. '_' .. k

				if rank then

					rank = mw.ustring.gsub(rank, '^&[MNmn][Dd][Aa][Ss][Hh];', '—')

					rank = mw.ustring.gsub(rank, '^[–%-]', '—')

				end

				local thisweek = get_rank(rank)

				row:tag('td')

					:css('background', get_color(lastweek, thisweek))

					:wikitext(format_cell_text(rank))

				lastweek = thisweek

			end

			-- After the last poll

			if plastweek < maxweeks then

				rank = args'poll' .. i .. '_final'

				local colspan = (maxweeks - plastweek) - (rank and 1 or 0)

				row:tag('td')

					:attr('colspan', (colspan > 1) and colspan or nil)

					:css('background', colors'not released'])

					:wikitext(labels'not released'])

				if rank and colspan > 0 then

					rank = mw.ustring.gsub(rank, '^&[MNmn][Dd][Aa][Ss][Hh];', '—')

					rank = mw.ustring.gsub(rank, '^[–%-]', '—')

					local thisweek = get_rank(rank)

					row:tag('td')

						:css('background', get_color(lastweek, thisweek))

						:wikitext(format_cell_text(rank))

				end				

			end

		end

	end

	-- Add legend

	local line1, line2 = '', ''

	if legend'+' or legend'-' then

		for k,v in ipairs({'+', '-'}) do

			line1 = line1 .. ' <span style="color:' .. colorsv .. '">██</span>'

			line1 = line1 .. ' ' .. labelsv

		end

	end

	for k,v in ipairs({'—', 'RV', 'т', '( )'}) do

		if legendv then line2 = line2  .. ' ' .. v .. ' = ' .. labelsv end

	end

	if line1 ~= '' or line2 ~= '' then

		caption:wikitext('<br /><small>\'\'\'' .. labels'legend' .. ':\'\'\'' .. line1)

		if line1 ~= '' and line2 ~= '' then

			caption:wikitext('<br />')

		end

		caption:wikitext(line2 .. '</small>')

	end

	

	checkargs(args)



	local trackstr = (#tracking > 0) and table.concat(tracking, '') or ''

	if #preview > 0 then

		trackstr = require('Module:If preview')._warning({

			'Unknown parameters ' .. table.concat(preview, '; ') .. '.'

		}) .. trackstr

	end



	return frame:extensionTag{ name = 'templatestyles', args = { src = templatestyles} } 

		.. tostring(root) .. trackstr

end



return p