Editing Module:Medical cases chart

local yesno = require('Module:Yesno')
local BarBox = unpack(require('Module:Bar'))

local lang = mw.getContentLanguage()
local language = lang:getCode()
local i18n = require('Module:Medical cases chart/i18n')[language]
assert(i18n, 'no chart translations to: ' .. mw.language.fetchLanguageName(language, 'en'))
local monthAbbrs = {}
for i = 1, 12 do
	monthAbbrs[i] = lang:formatDate('M', '2020-' .. ('%02d'):format(i))
end

local p = {}


function p._findIntervalRow(tRows, nTime, nTol, bAll)
	-- Loop backwards in tRows, assuming it to have monotonically increasing nDate entries in forward order.
	-- The first row with nDate within nTime +-nTol is returned.
	-- If nDate table entry is nil, the row will be skipped.
	-- If moving backwards a time stamp is found dating back to before tolerance window, nil is returned.
	-- If the end of tRows is reached without a match for the tolerance window, also nil is returned.
	-- With bAll present and true all rows back to the specified time window will be returned, or all rows back to
	-- the first row, that does not lie beyond nTime +-nTol if no match was found.
	local tRet = nil
	if bAll then
		tRet = {}
	end
	for nRowNum = #tRows, 1 ,-1 do
		if tRows[nRowNum] and tRows[nRowNum].nDate then
			local nDiff = nTime - tRows[nRowNum].nDate
			if nDiff > -nTol then
				if nDiff < nTol then
					if bAll then
						tRet[#tRet + 1] = tRows[nRowNum]
						return tRet
					else
						return tRows[nRowNum]
					end
				else
					return bAll and tRet or nil
				end
			end
		end
		if bAll then
			tRet[#tRet + 1] = tRows[nRowNum]
		end
	end
	--return tRows[nRowNum]
	return nil
end


function p._toggleButton(active, customtoggles, id, label)
	local on  = active and '' or ' mw-collapsed'
	local off = active and ' mw-collapsed' or ''
	local outString =
		'<span class="mw-collapsible' .. on  .. customtoggles .. '" id="mw-customcollapsible-' .. id .. '" ' ..
		'style="border:2px solid lightblue">' .. label .. '</span>' ..
		'<span class="mw-collapsible' .. off .. customtoggles .. '" id="mw-customcollapsible-' .. id .. '">' .. label  .. '</span>'
	return outString
end

function p._yearToggleButton(year)
	return p._toggleButton(year.l, ' mw-customtoggle-' .. year.year, year.year, year.year)
end

function p._monthToggleButton(year, month)
	local lmon, label = lang:lc(month.mon), month.mon
	local id = (year or '') .. lmon
	local customtoggles = ' mw-customtoggle-' .. id

	if month.s then
		label = label .. '&nbsp;' .. month.s -- "Mmm ##"
		if month.s ~= month.e then -- "Mmm ##–##"
			label = label .. '–' .. month.e
		end
	else
		customtoggles = customtoggles .. (month.l and customtoggles .. month.l or '')
	end

	for i, combination in ipairs(month.combinations) do
		customtoggles = customtoggles .. ' mw-customtoggle-' .. combination -- up to 2 combinations per month so no need to table.concat()
	end

	return p._toggleButton(false, customtoggles, id, label)
end

function p._lastXToggleButton(years, duration, combinationsL)
	local months, id = years[#years].months, 'l' .. duration
	local i, customtoggles = #months, {' mw-customtoggle-' .. id}

	if #years > 1 then
		local year = years[#years].year
		while months[i].l do
			customtoggles[#customtoggles+1] = ' mw-customtoggle-' .. year .. lang:lc(months[i].mon) .. '-' .. id
			if i == 1 then
				if year == years[#years].year then
					year = years[#years-1].year
					months = years[#years-1].months
					i = #months
				else -- either first month is also lastX month or lastX spans more than 2 years, which is not intended yet
					break
				end
			else
				i = i - 1
			end
		end
	else
		while i > 0 and months[i].l do
			customtoggles[#customtoggles+1] = ' mw-customtoggle-' .. lang:lc(months[i].mon) .. '-' .. id
			i = i - 1
		end
	end

	for i, combinationL in ipairs(combinationsL) do
		customtoggles[#customtoggles+1] = ' mw-customtoggle-' .. combinationL -- up to 3 combinationsL in 90 days
	end

	return p._toggleButton(true, table.concat(customtoggles), id, mw.ustring.format(i18n.lastXDays, duration))
end

function p._buildTogglesBar(dateList, duration, nooverlap)
	local years = {{year=dateList[1].year, months={{mon=dateList[1].mon, combinations={}}}}}
	local months, combinationsL = years[1].months, {}

	local function addMonth(month)
		if month.mon ~= months[#months].mon then -- new month
			if month.year ~= years[#years].year then -- new year
				years[#years+1] = {year=month.year, months={}}
				months = years[#years].months -- switch months list
			end
			months[#months+1] = {mon=month.mon, combinations={}}
		end
	end
	for i = 2, #dateList do -- deduplicate years and months
		if #dateList[i] == 0 then -- specific date
			addMonth(dateList[i])
			months[#months].l = months[#months].l or dateList[i].l -- so that both ...-mon and ...-mon-lX classes are created
		elseif #dateList[i] == 1 then -- interval within month
			addMonth(dateList[i][1])
			months[#months].l = months[#months].l or dateList[i].l
		else -- multimonth interval
			for j, month in ipairs(dateList[i]) do
				addMonth(month)
				months[#months].combinations[#months[#months].combinations+1] = dateList[i].id
			end
			combinationsL[#combinationsL+1] = dateList[i].id:find('-l%d+$') and dateList[i].id
		end
	end

	if nooverlap then
		local lastDate = dateList[#dateList]
		months[#months].e = tonumber(os.date('%d', lastDate.nDate or lastDate.nEndDate or lastDate.nAltEndDate)) -- end of final month

		local i = #dateList
		repeat
			i = i - 1
		until i == 0 or (dateList[i].mon or dateList[i][1].mon) ~= months[#months].mon
		if i == 0 then -- start of first and final month
			months[#months].s = tonumber(os.date('%d', dateList[1].nDate))
		else
			months[#months].s = 1
		end
	end

	years[#years].l = true -- to activate toggle and respective months bar

	local monthToggles, divs = {}, nil
	if #years > 1 then
		local yearToggles, monthsDivs = {}, {}
		for i, year in ipairs(years) do
			yearToggles[#yearToggles+1] = p._yearToggleButton(year)
			monthToggles = {}
			months = year.months
			for j, month in ipairs(months) do
				monthToggles[#monthToggles+1] = p._monthToggleButton(year.year, month)
			end
			monthsDivs[#monthsDivs+1] =
				'<div class="mw-collapsible' .. (year.l and '' or ' mw-collapsed') ..
				'" id="mw-customcollapsible-' .. year.year .. '">' .. table.concat(monthToggles) .. '</div>'
		end
		divs = '<div>' .. table.concat(yearToggles) .. '</div>' .. table.concat(monthsDivs)
	else
		for i, month in ipairs(months) do
			monthToggles[#monthToggles+1] = p._monthToggleButton(nil, month)
		end
		divs = '<div>' .. table.concat(monthToggles) .. '</div>'
	end
	divs = divs .. '<div>' .. p._lastXToggleButton(years, duration, combinationsL) .. '</div>'
	return '<div class="nomobile" style="text-align:center">' .. divs .. '</div>'
end

local numwidth = {n=0, t=2.45, m=3.5, d=3.5, w=4.55, x=5.6}

local bkgClasses = {
	'mcc-d',	--deaths
	'mcc-r',	--recoveries
	'mcc-c',	--cases or altlbl1
	'mcc-a2',	--altlbl2
	'mcc-a3'	--altlbl3
}

function p._customBarStacked(args)
	local barargs = {}

	barargs[1] = args[1]

	local function _numwidth(i)
		return args.numwidth:sub(i,i)
	end

	if args[7] or args[8] then -- is it acceptable to have one and not the other?
		barargs[2] =
			'<span class=mcc-r' .. _numwidth(1) .. '>' .. (args[7] or '') .. '</span>' ..
			'<span class=mcc-l' .. _numwidth(2) .. '>' .. (args[8] or '') .. '</span>'
	end
	if #args.numwidth == 4 then
		barargs.note2 = (args[9] or args[10]) and
			(args.numwidth:sub(3,3) ~= 'n' and '<span class=mcc-r' .. _numwidth(3) .. '>' .. (args[9] or '') .. '</span>' or '') ..
			'<span class=mcc-l' .. _numwidth(4) .. '>' .. (args[10] or '') .. '</span>'
		or ''
	end

	for i = 1, 5 do
		barargs[i+2] = args[i+1] / args.divisor
		barargs['title' .. i] = args[i+1]
	end

	barargs.align = 'cdcc'
	barargs.bkgclasses = bkgClasses
	barargs.collapsed = args.collapsed
	barargs.id = args.id

	return BarBox.stacked(barargs)
end

function p._row(args)
	local barargs = {}

	barargs[1] = (args[1] or '⋮') .. (args.note0 or '')
	barargs[2] = args[2] or 0
	barargs[3] = args[3] or 0

	if args['alttot1'] then
		barargs[4] = args['alttot1']
	elseif args[4] then
		barargs[4] = (args[4] or 0) - (barargs[2] or 0) - (barargs[3] or 0)
	else
		barargs[4] = 0
	end

	barargs[5] = args[5] or 0

	if args['alttot2'] then
		barargs[6] = args['alttot2']
	elseif args[6] then
		barargs[6] = (args[6] or 0) - (barargs[2] or 0) - (barargs[3] or 0)
	else
		barargs[6] = 0
	end

	barargs[7] = args[7]

	local function changeArg(firstright, valuecol, changecol)
		local change = ''
		if args['firstright' .. firstright] then
			change = '(' .. i18n.na .. ')'
		elseif not args[1] and args[valuecol] then
			change = '(=)'
		else
			change = args[changecol] and '(' .. args[changecol] .. ')' or ''
		end
		change = change .. (args['note' .. firstright] or '')

		return change ~= '' and change
	end

	barargs[8] = changeArg(1, 7, 8)
	barargs[9] = args[9]
	barargs[10] = changeArg(2, 9, 10)

	barargs.divisor = args.divisor
	barargs.numwidth = args.numwidth

	local dates
	if args.collapsible then
		local duration = args.duration
		if args.daysToEnd >= duration then
			barargs.collapsed = true
		else
			barargs.collapsed = false
		end

		if args.nooverlap and args.daysToEnd < duration then
			barargs.id = 'l' .. duration
		elseif args.nDate then
			dates = {year=tonumber(os.date('%Y', args.nDate)), mon=lang:formatDate('M', os.date('%Y-%m', args.nDate)),
				l=args.daysToEnd < duration and '-l' .. duration, nDate=args.nDate}
			barargs.id = (args.multiyear and dates.year or '') .. lang:lc(dates.mon) .. (dates.l or '')
		else
			local id, y, m, ey, em = {},
				tonumber(os.date('%Y', args.nStartDate or args.nAltStartDate)),
				tonumber(os.date('%m', args.nStartDate or args.nAltStartDate)),
				tonumber(os.date('%Y', args.nEndDate   or args.nAltEndDate  )),
				tonumber(os.date('%m', args.nEndDate   or args.nAltEndDate  ))
			dates = {nStartDate=args.nStartDate, nAltStartDate=args.nAltStartDate, nEndDate=args.nEndDate, nAltEndDate=args.nAltEndDate}

			repeat
				id[#id+1] = (args.multiyear and y or '') .. lang:lc(monthAbbrs[m])
				dates[#dates+1] = {year=y, mon=monthAbbrs[m]}
				y = y + math.floor(m / 12)
				m = m % 12 + 1
			until y == ey and m > em or y > ey

			dates.l = args.daysToEnd < duration and '-l' .. duration
			id = table.concat(id, '-') .. (dates.l or '')
			barargs.id = id
			dates.id = id
		end
	else
		barargs.collapsed = false
	end

	return p._customBarStacked(barargs), dates
end

function p._buildBars(args)
	local frame = mw.getCurrentFrame()
	local updatePeriod = 86400 -- temporary implementation only supports daily updates

	local function getUnix(timestamp)
		return lang:formatDate('U', timestamp)
	end
	
	-- some info for changetype 'w'
	local sChngTp1 = args.changetype1
	local sChngTp2 = args.changetype2
	local xData1Key = args.right1data or 3
	local xData2Key = args.right2data or 1
	xData1Key = (type(xData1Key) == "number") and (xData1Key+1) or xData1Key
	xData2Key = (type(xData2Key) == "number") and (xData2Key+1) or xData2Key
	local nPop = not (args.population == nil) and tonumber(args.population) or nil
	local bIsW1 = sChngTp1 == 'w' and nPop
	local bIsW2 = sChngTp2 == 'w' and nPop

	local rows, prevRow, tStats = {}, {}, {}
	local nData1Diff1Max, nData1Diff1MaxDate, nData2Diff1Max, nData2Diff1MaxDate
	local nData1i7Max, nData1i7MaxDate, nData2i7Max, nData2i7MaxDate
	for line in mw.text.gsplit(args.data, '\n') do
		local i, barargs = 1, {}
		-- line parameter parsing, basic type/missing value handling
		for parameter in mw.text.gsplit(line, ';') do
			if parameter:find('^%s*%a') then
				parameter = mw.text.split(parameter, '=')
				parameter[1] = mw.text.trim(parameter[1])
				if parameter[1]:find('^alttot') then
					parameter[2] = tonumber(frame:callParserFunction('#expr', parameter[2]))
				else
					parameter[2] = mw.text.trim(parameter[2])
					if parameter[1]:find('^firstright') then
						parameter[2] = yesno(parameter[2])
					elseif parameter[2] == '' then
						parameter[2] = nil
					end
				end
				barargs[parameter[1]] = parameter[2]
			else
				parameter = mw.text.trim(parameter)
				if parameter ~= '' then
					if i >= 2 and i <= 6 then
						parameter = tonumber(frame:callParserFunction('#expr', parameter))
						if not parameter then
							error(('Data parameters 2 to 6 must not be formatted. i=%d, line=%s'):format(i, line))
						end
					end
					barargs[i] = parameter
				end
				i = i + 1
			end
		end

		local bValid, nDateDiff
		-- get relevant date info based on previous row
		if barargs[1] then
			bValid, barargs.nDate = pcall(getUnix, barargs[1])
			assert(bValid, 'invalid date "' .. barargs[1] .. '"')
			if prevRow.nDate or prevRow.nEndDate then
				nDateDiff = barargs.nDate - (prevRow.nDate or prevRow.nEndDate)
				if nDateDiff > updatePeriod then
					if nDateDiff == 2 * updatePeriod then
						prevRow = {nDate=barargs.nDate-updatePeriod}
						prevRow[1] = os.date('%Y-%m-%d', prevRow.nDate)
					else
						prevRow = {nStartDate=(prevRow.nDate or prevRow.nEndDate)+updatePeriod, nEndDate=barargs.nDate-updatePeriod}
					end
					rows[#rows+1] = prevRow
				end
			else
				prevRow.nEndDate = barargs.nDate - updatePeriod
				if prevRow.nStartDate == prevRow.nEndDate then
					prevRow.nDate = prevRow.nEndDate
					prevRow[1] = os.date('%Y-%m-%d', prevRow.nDate)
				-- as nAltStartDate assumes a minimal multiday interval, it's possible for it to be greater if a true previous span is 1 day
				elseif prevRow.nAltStartDate and prevRow.nAltStartDate >= prevRow.nEndDate then
					error('a row in a consecutive intervals group is 1 day long and misses the date parameter')
				end
			end
		else
			if barargs.enddate then
				bValid, barargs.nEndDate = pcall(getUnix, barargs.enddate)
				assert(bValid, 'invalid enddate "' .. barargs.enddate .. '"')
			end
			if prevRow.nDate or prevRow.nEndDate then
				barargs.nStartDate = (prevRow.nDate or prevRow.nEndDate) + updatePeriod
				if barargs.nStartDate == barargs.nEndDate then
					barargs.nDate = barargs.nEndDate
					barargs[1] = os.date('%Y-%m-%d', barargs.nDate)
				end
			else
				prevRow.nAltEndDate = (prevRow.nStartDate or prevRow.nAltStartDate) + updatePeriod
				barargs.nAltStartDate = prevRow.nAltEndDate + updatePeriod
				if barargs.nEndDate and barargs.nAltStartDate >= barargs.nEndDate then
					error('a row in a consecutive intervals group is 1 day long and misses the date parameter')
				end
			end
		end

		-- update tStats if at least one column changetype is 'w'
		local tBarStats = nil
		if barargs[1] and (bIsW1 or bIsW2) then
			bValid, barargs.nDate = pcall(getUnix, barargs[1])
			assert(bValid, 'invalid date "' .. barargs[1] .. '"')
			barargs.nDate = tonumber(barargs.nDate)
			tBarStats = {}
			local tBarStats1 = tStats[barargs.nDate-86400] -- previous days info
			local tBarStats7 = tStats[barargs.nDate-604800] -- 7 days before info
			local tBarStats14 = tStats[barargs.nDate-1209600] -- 14 days before info
			local nData1 = barargs[xData1Key] or barargs[4]
			local nData2 = barargs[xData2Key] or barargs[2]
				
				
--	local nData1Diff1Max, nData1Diff1MaxDate, nData12Diff1Max, nData2Diff1MaxDate
--	local nData1i7Max, nData1i7MaxDate, nData12i7Max, nData2i7MaxDate

			if bIsW1 and nData1 then
				tBarStats.nData1 = nData1
				-- if stats exist from day before
				if not (tBarStats1 == nil) and not (tBarStats1.nData1 == nil) then
					tBarStats.nData1Diff1 = nData1 - tBarStats1.nData1
					if nData1Diff1Max == nil or nData1Diff1Max < tBarStats.nData1Diff1 then
						nData1Diff1Max = tBarStats.nData1Diff1
						nData1Diff1MaxDate = barargs[1]
					end
				end
				-- if stats exist from 7 days before
				if not (tBarStats7 == nil) then
					if not (tBarStats7.nData1 == nil) then
						tBarStats.nData1Diff7 = nData1 - tBarStats7.nData1
						if nData1i7Max == nil or nData1i7Max < tBarStats.nData1Diff7/nPop*100000 then
							nData1i7Max = tBarStats.nData1Diff7/nPop*100000
							nData1i7MaxDate = barargs[1]
						end
					end
					if not (tBarStats7.nData1Diff1 == nil) then
						tBarStats.nData1P7Diff1 = tBarStats7.nData1Diff1
					end
				end
				-- if stats exist from 14 days before
				if not (tBarStats14 == nil) then
					if not (tBarStats14.nData1 == nil) then
						tBarStats.nData1Diff14 = nData1 - tBarStats14.nData1
					end
					if not (tBarStats14.nData1Diff1 == nil) then
						tBarStats.nData1P14Diff1 = tBarStats14.nData1Diff1
					end
				end
			end
			if bIsW2 and nData2 then
				tBarStats.nData2 = nData2
				-- if stats exist from day before
				if not (tBarStats1 == nil) and not (tBarStats1.nData2 == nil) then
					tBarStats.nData2Diff1 = nData2 - tBarStats1.nData2
					if nData2Diff1Max == nil or nData2Diff1Max < tBarStats.nData2Diff1 then
						nData2Diff1Max = tBarStats.nData2Diff1
						nData2Diff1MaxDate = barargs[1]
					end
				end
				-- if stats exist from 7 days before
				if not (tBarStats7 == nil) then
					if not (tBarStats7.nData2 == nil) then
						tBarStats.nData2Diff7 = nData2 - tBarStats7.nData2
						if nData2i7Max == nil or nData2i7Max < tBarStats.nData2Diff7/nPop*100000 then
							nData2i7Max = tBarStats.nData2Diff7/nPop*100000
							nData2i7MaxDate = barargs[1]
						end
					end
					if not (tBarStats7.nData2Diff1 == nil) then
						tBarStats.nData2P7Diff1 = tBarStats7.nData2Diff1
					end
				end
				-- if stats exist from 14 days before
				if not (tBarStats14 == nil) then
					if not (tBarStats14.nData2 == nil) then
						tBarStats.nData2Diff14 = nData2 - tBarStats14.nData2
					end
					if not (tBarStats14.nData2Diff1 == nil) then
						tBarStats.nData2P14Diff1 = tBarStats14.nData2Diff1
					end
				end
			end
			tStats[barargs.nDate] = tBarStats
		end

		local function fillCols(col, change)
			local data = args['right' .. col .. 'data']
			local changetype = args['changetype' .. col]
			local value, num, prevnum

			if data == 'alttot1' then
				num = barargs.alttot1 or barargs[4]
				prevnum = prevRow.alttot1 or prevRow[4]
			elseif data == 'alttot2' then
				num = barargs.alttot2 or barargs[6]
				prevnum = prevRow.alttot2 or prevRow[6]
			elseif data then
				num = barargs[data+1]
				prevnum = prevRow[data+1]
			end

			-- changetype w
			if not (tBarStats == nil) and not (tBarStats["nData"..col] == nil) then
				local nDiff7 = tBarStats["nData"..col.."Diff7"]
				local sChngCmt = ""
				if col == 1 and not (nData1i7Max == nil) then
					sChngCmt = "all time high: " .. mw.ustring.format('%.1f', nData1i7Max) .. " on " .. nData1i7MaxDate
				elseif col == 2 and not (nData2i7Max == nil) then
					sChngCmt = "all time high: " .. mw.ustring.format('%.1f', nData2i7Max) .. " on " .. nData2i7MaxDate
				end
				if nDiff7 == nil then
					change = i18n.na
				else
					change = '<span title="'.. sChngCmt .. '">' .. tostring(mw.ustring.format('%.1f', nDiff7/args.population*100000)) .. '</span>'
				end
				local nValue = tBarStats["nData"..col]
				local nDiff1 = tBarStats["nData"..col.."Diff1"]
				local nP7Diff1 = tBarStats["nData"..col.."P7Diff1"]
				local nP14Diff1 = tBarStats["nData"..col.."P14Diff1"]
				local sCmnt
				if nDiff1 == nil then
					sCmnt = ""
				else
					sCmnt = "daily change: +" .. lang:formatNum(nDiff1)
				end
				if not (nP7Diff1 == nil) and not (sCmnt == "") then
					sCmnt = sCmnt .. ", 7 days before: +" .. lang:formatNum(nP7Diff1)
				end
				if not (nP14Diff1 == nil) and not (sCmnt == "") then
					sCmnt = sCmnt .. ", 14 days before: +" .. lang:formatNum(nP14Diff1)
				end
				if col == 1 and not (nData1Diff1Max == nil) and not (sCmnt == "") then
					sCmnt = sCmnt .. ", all-time high: +" .. lang:formatNum(nData1Diff1Max) .. " on " .. nData1Diff1MaxDate
				end
				if col == 2 and not (nData2Diff1Max == nil) and not (sCmnt == "") then
					sCmnt = sCmnt .. ", all-time high: +" .. lang:formatNum(nData2Diff1Max) .. " on " .. nData2Diff1MaxDate
				end
				value = '<span title="' .. sCmnt ..'">' .. lang:formatNum(nValue)  .. '</span>'
			
			elseif data and num then -- nothing in column, source found, and data exists
				value = changetype == 'o' and '' or lang:formatNum(num) -- set value to num if changetype isn't 'o'
				if not change and not barargs['firstright' .. col] then
					if prevnum and prevnum ~= 0 then -- data on previous row
						if num - prevnum ~= 0 then --data has changed since previous row
							local nChange = num - prevnum
							if changetype == 'a' then -- change type is "absolute"
								if nChange > 0 then
									change = '+' .. lang:formatNum(nChange)
								end
							elseif changetype == 'w' and args.population then -- changetype == 'r' or 
								 -- change type is "r"(olling average over 7 days period) or "w"(eekly incidence per 100.000 pop)
								if barargs.nDate and rows then
									-- find data row from 7 days before +- 1 hour
									local tIntervRow = p._findIntervalRow(rows, barargs.nDate-7*24*3600, 3600, false)
									local tPrevDayRow = p._findIntervalRow(rows, barargs.nDate-24*3600, 3600, false)
									if tIntervRow then
										local nDatCol = (col==1) and 4 or 2
										local nDiff = tIntervRow[nDatCol] and (num - tIntervRow[nDatCol]) or nil
										if changetype == 'r' then
											change = nDiff and ('<span title="7 days rolling average of daily change">r7: ' .. tostring(mw.ustring.format('%.0f', nDiff/7)) .. '</span>') or i18n.na
										else
											change = nDiff and ('<span title="7 days incidence per 100,000 population.">' .. tostring(mw.ustring.format('%.1f', nDiff/args.population*100000)) .. '</span>') or i18n.na
											if tPrevDayRow and tPrevDayRow[nDatCol] then
												value = '<span title="daily change: +' .. lang:formatNum(num - tPrevDayRow[nDatCol]) .. '>' .. value  .. '</span>'
											end
										end
									else
										change = i18n.na
									end
								else
									change = i18n.na
								end


							else -- change type is "percent", "only percent" or undefined
								local percent = 100 * nChange / prevnum -- calculate percent
								local rounding = math.abs(percent) >= 10 and '%.0f' or math.abs(percent) >= 1 and '%.1f' or '%.2f'
								percent = tonumber(rounding:format(percent)) -- round to two sigfigs

								if percent > 0 then
									change = '+' .. lang:formatNum(percent) .. '%'
								elseif percent < 0 then
									change = lang:formatNum(percent) .. '%'
								else
									change = '='
								end
							end
						else -- data has not changed since previous row
							change = '='
						end
					else -- no data on previous row
						barargs['firstright' .. col] = true -- set to (n.a.)
					end
				end
			end

			return value, change
		end

		if not barargs[7] then
			barargs[7], barargs[8] = fillCols(1, barargs[8])
		end
		if not barargs[9] then
			barargs[9], barargs[10] = fillCols(2, barargs[10])
		end

		rows[#rows+1] = barargs
		prevRow = barargs
	end

	--error(mw.dumpObject(tStats))

	-- calculate and pass repetitive (except daysToEnd) parameters to each row
	local lastRow = rows[#rows]
	local total = {lastRow[2] or 0, lastRow[3] or 0, [4]=lastRow[5] or 0}
	total[3] = lastRow.alttot1 or lastRow[4] and lastRow[4] - total[1] - total[2] or 0
	total[5] = lastRow.alttot2 or lastRow[6] and lastRow[6] - total[1] - total[2] or 0
	local divisor = (total[1] + total[2] + total[3] + total[4] + total[5]) / (args.barwidth - 5) --should be -3 if borders didn't go inward
	local firstDate, lastDate = rows[1].nDate, lastRow.nDate or lastRow.nEndDate
	local multiyear = os.date('%Y', firstDate) ~= os.date('%Y', lastDate - (args.nooverlap and args.duration * 86400 or 0))
	if args.collapsible ~= false then
		args.collapsible = (lastDate - firstDate) / 86400 >= args.duration
	end

	local bars, dateList = {}, {}
	for i, row in ipairs(rows) do -- build rows
		row.divisor = divisor
		row.numwidth = args.numwidth
		row.collapsible = args.collapsible
		row.duration = args.duration
		row.nooverlap = args.nooverlap
		row.daysToEnd = (lastDate - (row.nDate or row.nEndDate or row.nAltEndDate)) / 86400
		row.multiyear = multiyear

		bars[#bars+1], dateList[#dateList+1] = p._row(row)
	end

	return table.concat(bars, '\n'), dateList
end

p._barColors = { -- also in styles.css
	'#A50026',	--deaths
	'SkyBlue',	--recoveries
	'Tomato',	--cases or altlbl1
	'Gold',		--altlbl2
	'OrangeRed'	--altlbl3
}

function p._legend0(args)
	return
		'<span style="font-size:90%; margin:0px">' ..
			'<span style="background-color:' .. (args[1] or 'none') ..
			'; border:' .. (args.border or 'none') ..
			'; color:' .. (args[1] or 'none') .. '">' ..
				'&nbsp;&nbsp;&nbsp;&nbsp;' .. '</span>' ..
			'&nbsp;' .. (args[2] or '') .. '</span>'
end

function p._chart(args)
	for key, value in pairs(args) do
		if ({float=1, barwidth=1, numwidth=1, changetype=1})[key:gsub('%d', '')] then
			args[key] = value:lower()
		end
	end

	local barargs = {}

	barargs.css = 'Module:Medical cases chart/styles.css'
	barargs.float = args.float or 'right'

	args.barwidth = args.barwidth or 'medium'
	local barwidth
	if args.barwidth == 'thin' then
		barwidth = 120
	elseif args.barwidth == 'medium' then
		barwidth = 280
	elseif args.barwidth == 'wide' then
		barwidth = 400
	elseif args.barwidth == 'auto' then
		barwidth = 'auto'
	else
		error('unrecognized barwidth')
	end

	local function _numwidth(i)
		local nw = args.numwidth:sub(i,i)
		return assert(numwidth[nw], 'unrecognized numwidth[' .. i .. ']')
	end

	args.numwidth = args.numwidth or 'mm'
	if args.numwidth:sub(1,1) == 'n' or args.numwidth:sub(2,2) == 'n' or args.numwidth:sub(4,4) == 'n' then
		error('"n" is only allowed in numwidth[3]')
	end

	local buffer = 0.3 --until automatic numwidth determination
	local right1width, right2width = _numwidth(1) + 0.3 + _numwidth(2) + buffer, 0
	if #args.numwidth == 4 then
		right2width = _numwidth(3) + _numwidth(4) + buffer
		if args.numwidth:sub(3,3) ~= 'n' then
			right2width = right2width + 0.3
		end
		if args.right2 then
			right2width = math.ceil(right2width / 0.88 * 100) / 100 -- from td scale to th
		else
			right1width = right1width + 0.8 + right2width
			right2width = 0
		end
	end
	right1width = math.ceil(right1width / 0.88 * 100) / 100

	if tonumber(barwidth) then
		-- transform colswidth from th to td scale, add it with border-spacing, and finally transform to table scale
		local relwidth = math.ceil(((7.08 + right1width + right2width) * 0.88 + 0.8 * (args.right2 and 5 or 4)) * 88) / 100
		barargs.width = 'calc(' .. relwidth .. 'em + ' .. barwidth .. 'px)' --why do the bar borders go inward (no +2)?
		barargs.barwidth = barwidth .. 'px'
	else
		barargs.width = 'auto'
		barargs.barwidth = 'auto'
	end
	barargs.lineheight = args.rowheight

	local title = {}

	local function spaces(n)
		local nbsp = '&nbsp;'
		return '<span class="nowrap">' .. nbsp:rep(n) .. '</span>'
	end

	local location = lang:ucfirst(mw.ustring.gsub(args.location, i18n.the_, ''))
	local navbartitle = args.outbreak .. i18n._data .. '/' ..
		(args.location3 and args.location3 .. '/' or '') ..
		(args.location2 and args.location2 .. '/' or '') ..
		location .. i18n._medicalCasesChart

	local navbar = require('Module:Navbar')._navbar
	title[1] = (args.pretitle and args.pretitle .. ' ' or '') ..
		args.disease .. ' ' .. i18n.casesIn .. ' ' .. args.location ..
		(args.location2 and ', ' .. args.location2 or '') ..
		(args.location3 and ', ' .. args.location3 or '') ..
		(args.posttitle and ' ' .. args.posttitle or '') .. spaces(2) ..'(' ..
		navbar({navbartitle, titleArg=':' .. mw.getCurrentFrame():getParent():getTitle(), mini=1, nodiv=1}) ..
		')<br />'

	title[2] = p._legend0({p._barColors[1], i18n.deaths})
	args.recoveries = args.recoveries == nil and true or args.recoveries
	title[3] = args.recoveries and spaces(3) .. p._legend0({p._barColors[2], args.reclbl or i18n.recoveries}) or ''
	title[4] = args.altlbl1 ~= 'hide' and spaces(3) .. p._legend0({p._barColors[3], args.altlbl1 or i18n.activeCases}) or ''
	title[5] = args.altlbl2 and spaces(3) .. p._legend0({p._barColors[4], args.altlbl2}) or ''
	title[6] = args.altlbl3 and spaces(3) .. p._legend0({p._barColors[5], args.altlbl3}) or ''

	local togglesbar, buildargs = nil, {}

	args.right1 = args.right1 or i18n.noOfCases
	args.duration = args.duration or 15
	args.nooverlap = args.nooverlap or false

	buildargs.barwidth = tonumber(barwidth) or 280
	buildargs.numwidth = args.numwidth:gsub('d', 'm')
	if args.datapage then
		local externalData = require('Module:Medical cases chart/data')._externalData
		buildargs.data = externalData(args)
	else
		buildargs.data = args.data
	end
	-- if no right1data and right1 title is cases, use 3rd classification
	buildargs.right1data = args.right1data or args.right1 == i18n.noOfCases and 3
	-- if no right2data and right2 title is deaths, use 1st classification
	buildargs.right2data = args.right2data or (args.right2 == i18n.noOfDeaths or args.right2 == i18n.noOfDeaths2) and 1
	buildargs.changetype1 = (args.changetype1 or args.changetype or ''):sub(1,1) -- 1st letter
	buildargs.changetype2 = (args.changetype2 or args.changetype or ''):sub(1,1) -- 1st letter
	buildargs.collapsible = args.collapsible
	buildargs.duration = args.duration
	buildargs.nooverlap = args.nooverlap
	buildargs.population = args.population

	local dateList
	barargs.bars, dateList = p._buildBars(buildargs)

	if buildargs.collapsible then
		togglesbar = p._buildTogglesBar(dateList, args.duration, args.nooverlap)
	end

	title[7] = togglesbar and '<br />' .. togglesbar or ''
	barargs.title = table.concat(title)

	barargs.left1 = '<div style="width:7.08em">' .. i18n.date .. '</div>'
	barargs.right1 = '<div class=center style="width:' .. right1width .. 'em">' .. args.right1 .. '</div>' --center isn't necessary with proper
	if args.right2 then																					   --numwidth, but better safe than sorry
		barargs.right2 = '<div class=center style="width:' .. right2width ..'em">' .. args.right2 .. '</div>'
	end

	barargs.footer = args.footer
	local box = BarBox.create(barargs)
	return tostring(box)
end

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

function p.barColors(frame)
	local args = getArgs(frame)
	return p._barColors[tonumber(args[1])]
end

function p.chart(frame)
	local args = getArgs(frame, {
		valueFunc = function (key, value)
			if value and value ~= '' then
				key = key:gsub('%d', '')
				if ({rowheight=1, duration=1, rightdata=1})[key] then -- if key in {...}
					return tonumber(value) or value
				end
				if ({recoveries=1, collapsible=1, nooverlap=1})[key] then
					return yesno(value)
				end
				return value
			end
			return nil
		end
	})
	return p._chart(args)
end

return p