Module:Wikidata

-- version 20200118 from master @cawiki

local p = {}

-- Initialization of variables --------------------

local i18n = {						-- internationalisation at [[Module:Wikidata/i18n]]
	["errors"] = {
		["property-not-found"] = "Property not found.",
		["qualifier-not-found"] = "Qualifier not found.",
	},
	
	["datetime"] = {
		-- $1 is a placeholder for the actual number
		["beforenow"] = "$1 BCE",	-- how to format negative numbers for precisions 0 to 5
		["afternow"] = "$1 CE",		-- how to format positive numbers for precisions 0 to 5
		["bc"] = '$1 "BCE"',		-- how print negative years
		["ad"] = "$1",				-- how print 1st century AD dates
		
		[0] = "$1 billion years",	-- precision: billion years
		[1] = "$100 million years",	-- precision: hundred million years
		[2] = "$10 million years",	-- precision: ten million years
		[3] = "$1 million years",	-- precision: million years
		[4] = "$100000 years",		-- precision: hundred thousand years; thousand separators added afterwards
		[5] = "$10000 years",		-- precision: ten thousand years; thousand separators added afterwards
		[6] = "$1 millennium",		-- precision: millennium
		[7] = "$1 century",			-- precision: century
		[8] = "$1s",				-- precision: decade
		-- the following use the format of #time parser function
		[9] = "Y",					-- precision: year, 
		[10] = "F Y",				-- precision: month
		[11] = "F j, Y",			-- precision: day
	},
	
	["years-old"] = {
		["singular"] = "",			-- year old, as in {{PLURAL:$1|singular|plural}}
		["plural"] = "",			-- years old
		["paucal"] = "",			-- for languages with 3 plural forms as in {{PLURAL:$1|singular|paucal|plural}}
	},
	
	["cite"] = {					-- Cite web parameters
		["url"]			= "url",
		["title"]		= "title",
		["website"]		= "website",
		["access-date"]	= "access-date",
		["archive-url"]	= "archive-url",
		["archive-date"]= "archive-date",
		["author"]		= "author",
		["publisher"]	= "publisher",
		["quote"]		= "quote",
		["language"]	= "language",
		["date"]		= "date",
		["pages"]		= "pages"
	}
}

local cases = {} -- functions for local grammatical cases defined at [[Module:Wikidata/i18n]]

local required = ... -- variadic arguments from require function
local wiki = 
{
	langcode = mw.language.getContentLanguage().code,
	module_title = required or mw.getCurrentFrame():getTitle()
}

-- Module local functions --------------------------------------------

-- Credit to http://stackoverflow.com/a/1283608/2644759, cc-by-sa 3.0
local function tableMerge(t1, t2)
	for k,v in pairs(t2) do
		if type(v) == "table" then
			if type(t1[k] or false) == "table" then
				tableMerge(t1[k] or {}, t2[k] or {})
			else
				t1[k] = v
			end
		else
			t1[k] = v
		end
	end
	return t1
end

local function loadI18n()
	local exist, res = pcall(require, wiki.module_title .. "/i18n")
	if exist and next(res) ~= nil then
		tableMerge(i18n, res.i18n)
		cases = res.cases
	end
end

loadI18n()

-- Argument is 'set' when it exists (not nil) or when it is not an empty string.
local function isSet(var)
	return not (var == nil or var == '')
end

-- Set local case to a label
local function case(localcase, label, ...)
	if not isSet(label) then return label end
	
	if localcase == "smallcaps" then
		return '<span style="font-variant: small-caps;">' .. label .. '</span>'
	elseif cases[localcase] then
		return cases[localcase](label, ...)
	end
	
	return label
end

-- Table of language codes: requested or default and its fallbacks
local function findLang(langcode)
	if mw.language.isKnownLanguageTag(langcode or '') == false then
		local cframe = mw.getCurrentFrame()
		local pframe = cframe:getParent()
		langcode = pframe and pframe.args.lang
		if mw.language.isKnownLanguageTag(langcode or '') == false then
			if not mw.title.getCurrentTitle().isContentPage then
				langcode = cframe:preprocess('{{int:lang}}')
			end
			if mw.language.isKnownLanguageTag(langcode or '') == false then
				langcode = wiki.langcode
			end
		end
	end
	local languages = mw.language.getFallbacksFor(langcode)
	table.insert(languages, 1, langcode)
	return languages
end

-- mw.wikibase.getLabelWithLang or getLabelByLang with a table of languages
local function getLabelByLangs(id, languages)
	local label
	local lang = languages[1]
	if lang == wiki.langcode then
		-- using getLabelWithLang when possible instead of getLabelByLang
		label, lang = mw.wikibase.getLabelWithLang(id)
	else
		lang = nil
		for _, l in ipairs(languages) do
			label = mw.wikibase.getLabelByLang(id, l)
			if label then
				lang = l
				break
			end
		end
	end
	
	return label, lang
end

-- Is gender femenine? true or false
local function feminineGender(id)
	local claims = mw.wikibase.getBestStatements(id or mw.wikibase.getEntityIdForCurrentPage(),'P21')
	if #claims == 0 then
		return false
	elseif claims[1].mainsnak.datavalue == nil then -- novalue or somevalue
		return false
	else
		local genderId = claims[1].mainsnak.datavalue.value.id
		if genderId == "Q6581072" or genderId == "Q1052281" or genderId == "Q43445" then -- female, transgender female, female organism
			return true
		end
	end
	return false
end

-- Fetch female form of label
local function feminineForm(id, lang)
	local feminine_claims = mw.wikibase.getBestStatements(id, 'P2521') -- female form of label
	for _, feminine_claim in ipairs(feminine_claims) do
		if feminine_claim.mainsnak.datavalue.value.language == lang then
			return feminine_claim.mainsnak.datavalue.value.text
		end
	end
end

-- Fetch unit symbol
local function unitSymbol(id, lang)
	local claims = findClaims(id, 'P5061')
	local langclaims = {}
	if claims then
		for _, snak in ipairs(claims) do
			if snak.mainsnak and snak.mainsnak.datavalue and snak.mainsnak.datavalue.value and
				not langclaims[snak.mainsnak.datavalue.value.language] -- just the first one by language
				then
					langclaims[snak.mainsnak.datavalue.value.language] = snak.mainsnak.datavalue.value.text
			end
		end
		for _, l in ipairs(lang) do
			if langclaims[l] then
				return langclaims[l]
			end
		end
	end
	return langclaims["mul"] -- last try
end

-- Add an icon for no label in requested language
local function addLabelIcon(label_id, lang, uselang, icon)
	local ret_lang, ret_icon = '', ''
	if icon then
		if lang and lang ~= uselang then
			ret_lang = " <sup>(" .. lang .. ")</sup>"
		end
		if label_id and (lang == nil or lang ~= uselang) then
			ret_icon = " [[File:Noun Project label icon 1116097 cc mirror.svg|10px|"
				.. mw.message.new('Translate-taction-translate'):inLanguage(uselang):plain()
				.. "|link=https://www.wikidata.org/wiki/Special:EntityPage/" .. label_id .. "?uselang=" .. uselang .. "]]"
		end
	end
	return ret_lang .. ret_icon
end

-- Escape URL escapes to avoid Lua captures
local function urlEscapes(text)
	return mw.ustring.gsub(text, "(%%%d)", "%%%1")
end

-- expandTemplate or callParserFunction
local function expandBraces(text, formatting)
	if text == nil or formatting == nil then return text end
	-- only expand braces if provided in argument, not included in value as in Q1164668
	if mw.ustring.find(formatting, '{{', 1, true) == nil then return text end
	if type(text) ~= "string" then
		text = tostring(text)
	end
	
	for braces in mw.ustring.gmatch(text, "{{(.-)}}") do
		local parts = mw.text.split(braces, "|")
		local title_part = parts[1]
		local parameters = {}
		for i = 2, #parts do
			local subparts = mw.ustring.find(parts[i], "=")
			if subparts then
				parameters[mw.ustring.sub(parts[i], 1, subparts-1)] = mw.ustring.sub(parts[i], subparts+1, -1)
			else
				table.insert(parameters, parts[i])
			end
		end
		
		local braces_expanded
		if mw.ustring.find(title_part, ":")
			and mw.text.split(title_part, ":")[1] ~= mw.site.namespaces[10].name -- not a prefix Template:
			then
			braces_expanded = mw.getCurrentFrame():callParserFunction{name=title_part, args=parameters}
		else
			braces_expanded = mw.getCurrentFrame():expandTemplate{title=title_part, args=parameters}
		end
		braces = mw.ustring.gsub(braces, "([%^%$%(%)%%%.%[%]%*%+%-%?])", "%%%1") -- escape magic characters
		braces_expanded = urlEscapes(braces_expanded)
		text = mw.ustring.gsub(text, "{{" .. braces .. "}}", braces_expanded)
	end
	
	return text
end

-- Resolve Wikidata redirects, pending phab:T157868
local function resolveEntityId(id)
	if not id or not mw.wikibase.isValidEntityId(id) then return id end
	-- if no label in local language nor its fallbacks, maybe it is a redirect
	-- not using mw.title.new(id).isRedirect as it is expensive
	if mw.wikibase.getLabel(id) == nil then
		local entity = mw.wikibase.getEntity(id) -- expensive function
		if not entity then return nil end
		if id ~= entity.id then
			-- Qid redirected to be fixed
			-- see [[Special:WhatLinksHere/Template:Track/wikidata/redirect]]
			require(wiki.module_title .. '/debug').track('redirect')
			require(wiki.module_title .. '/debug').track('redirect/' .. id)
		else
			-- no redirect and no label, fix it to avoid expensive functions
			require(wiki.module_title .. '/debug').track('label')
			require(wiki.module_title .. '/debug').track('label/' .. id)
		end
		return entity.id
	end
	return id
end

-- format data type math
local function printDatatypeMath(data)
	return mw.getCurrentFrame():callParserFunction('#tag:math', data)
end

-- format data type musical-notation
local function printDatatypeMusical(data, formatting)
	local attr = {}
	if formatting == 'sound' then
		attr.sound = 1
	end
	return mw.getCurrentFrame():extensionTag('score', data, attr)
end

-- format data value string
local function printDatavalueString(data, parameters)
	if parameters.formatting == 'weblink' then 
		return '[' .. data .. ' ' .. mw.text.split(data, '//' )[2] .. ']'
	elseif mw.ustring.find((parameters.formatting or ''), '$1', 1, true) then -- formatting = a pattern
		return expandBraces(mw.ustring.gsub(parameters.formatting, '$1', {['$1']=data}), parameters.formatting)
	elseif parameters.case then
		return case(parameters.case, data, parameters.lang[1])
	else
		return data
	end
end

-- format data type url
local function printDatatypeUrl(data, parameters)
	return printDatavalueString(urlEscapes(data), parameters)
end

-- format data value globecoordinate
local function printDatavalueCoordinate(data, parameter)
	local globes = {['Q3134']='callisto',['Q596']='ceres',['Q15040']='dione',['Q2']='earth',['Q3303']='enceladus',
		['Q3143']='europa',['Q17975']='phoebe',['Q3169']='ganymede',['Q3123']='io',['Q17958']='iapetus',
		['Q308']='mercury',['Q15034']='mimas',['Q405']='moon',['Q15050']='rhea',['Q15047']='tethys',
		['Q111']='mars',['Q2565']='titan',['Q3359']='triton',['Q313']='venus',['Q3030']='vesta'}
	if parameter and string.find(parameter, '$lat', 1, true) and string.find(parameter, '$lon', 1, true) then
		local ret = mw.ustring.gsub(parameter, '$l[ao][tn]', {['$lat'] = data.latitude, ['$lon'] = data.longitude})
		if string.find(parameter, '$globe', 1, true) then
			local myglobe = 'earth'
			if isSet(data.globe) then
				local globenum = mw.text.split(data.globe, 'entity/')[2] -- http://www.wikidata.org/wiki/Q2
				myglobe = globes[globenum] or 'earth'
			end
			ret = mw.ustring.gsub(ret, '$globe', myglobe)
		end
		return expandBraces(ret, parameter)
	elseif parameter == 'latitude' then
		return data.latitude
	elseif parameter == 'longitude' then
		return data.longitude
	elseif parameter == 'dimension' then
		return data.dimension
	else --default formatting='globe'
		if data.globe == '' or data.globe == nil or data.globe == 'http://www.wikidata.org/entity/Q2' then
			return 'earth'
		else
			local globenum = mw.text.split(data.globe, 'entity/')[2]
			return globes[globenum] or globenum
		end
	end
end

local function roundPrecision(in_num, out_num)
	-- rounds out_num with significant figures of in_num (default precision)
	-- first, count digits after decimal mark, handling cases like '12.345e6'
	local exponent, prec
	local integer, dot, decimals, expstr = in_num:match('^(%d*)(%.?)(%d*)(.*)')
	local e = expstr:sub(1, 1)
	if e == 'e' or e == 'E' then
		exponent = tonumber(expstr:sub(2))
	end
	if dot == '' then
		prec = -integer:match('0*$'):len()
	else
		prec = #decimals
	end
	if exponent then
		-- So '1230' and '1.23e3' both give prec = -1, and '0.00123' and '1.23e-3' give 5.
		prec = prec - exponent
	end
	-- significant figures
	local in_bracket = 10^-prec -- -1 -> 10, 5 -> 0.00001
	local out_bracket = in_bracket * out_num / in_num
	out_bracket = 10^math.floor(math.log10(out_bracket)+.5) -- 1230 -> 1000, 0.00123 -> 0.001
	-- round it (credit to Luc Bloom from http://lua-users.org/wiki/SimpleRound)
	return math.floor(out_num/out_bracket + (out_num >=0 and 1 or -1) * 0.5) * out_bracket
end

-- format data value quantity
local function printDatavalueQuantity(data, parameters)
	local amount = data.amount
	amount = mw.ustring.gsub(amount, "%+", "")
	local sortkey = string.format("%09d", amount)
	local suffix = ""
	if string.sub(parameters.formatting or '', 1, 4) == "unit" or parameters.convert then
		-- example "unit": "http://www.wikidata.org/entity/Q174728"
		local unit_id = data.unit
		unit_id = mw.ustring.sub(unit_id, mw.ustring.find(unit_id, "Q"), -1)
		if string.sub(unit_id, 1, 1) == "Q" then
			local convert_to = parameters.convert
			if convert_to and convert_to ~= unit_id then
				-- convert units
				local conv_temp = { -- formulae for temperatures ºC, ºF, ªK: [from] = {[to] = 'formula'}
					['Q25267'] = {['Q42289'] = '$1*1.8+32', ['Q11597'] = '$1+273.15'},
					['Q42289'] = {['Q25267'] = '($1-32)/1.8', ['Q11597'] = '($1+459.67)*5/9'},
					['Q11597'] = {['Q25267'] = '$1-273.15', ['Q42289'] = '($1-273.15)*1.8000+32.00'}
				}
				if conv_temp[unit_id] and conv_temp[unit_id][convert_to] then
					local amount_f = mw.getCurrentFrame():callParserFunction('#expr', mw.ustring.gsub(conv_temp[unit_id][convert_to], "$1", amount))
					amount = math.floor(tonumber(amount_f) + 0.5)
					unit_id = convert_to
				else
					local conversions = mw.wikibase.getAllStatements(unit_id, 'P2442') -- conversion to standard unit
					table.insert(conversions, mw.wikibase.getBestStatements(unit_id, 'P2370')[1]) -- conversion to SI unit
					for _, conv in ipairs(conversions) do
						if conv.mainsnak.snaktype == 'value' then -- no somevalue nor novalue
							if conv.mainsnak.datavalue.value.unit == "http://www.wikidata.org/entity/" .. convert_to then
								amount = roundPrecision(amount, amount * tonumber(conv.mainsnak.datavalue.value.amount))
								unit_id = convert_to
								break
							end
						end
					end
				end
			end
			if parameters.formatting == "unitcode" then
				-- get unit symbol
				local unit_symbol = ''
				if parameters.lang[1] == wiki.langcode and pcall(require, wiki.module_title .. "/Units") then
					unit_symbol = require(wiki.module_title .. "/Units").getUnit(amount, '', unit_id, true, '')
				end
				if unit_symbol == '' then
					unit_symbol = unitSymbol(unit_id, parameters.lang)
				end
				if unit_symbol then
					suffix = " " .. unit_symbol
				end
			end
			if suffix == '' then
				-- get unit name
				local unit_label, lang = getLabelByLangs(unit_id, parameters.lang)
				if lang == wiki.langcode and pcall(require, wiki.module_title .. "/Units") then
					suffix = " " .. require(wiki.module_title .. "/Units").getUnit(amount, unit_label, unit_id, false, '')
				else
					suffix = " " .. (unit_label or unit_id) .. addLabelIcon(unit_id, lang, parameters.lang[1], parameters.editicon)
				end
			end
		end
	end
	amount = mw.language.new(parameters.lang[1]):formatNum(tonumber(amount))
	return amount .. suffix, sortkey
end

-- format data value time
local function printDatavalueTime(data, parameters)
	-- Dates and times are stored in ISO 8601 format
	local timestamp = data.time
	local post_format
	local calendar_add = ""
	
	if string.sub(timestamp, 1, 1) == '-' then
		post_format = i18n.datetime["bc"]
	elseif string.sub(timestamp, 2, 3) == '00' then
		post_format = i18n.datetime["ad"]
	else
		-- calendar model
		local calendar_model = {["Q12138"] = "gregorian", ["Q1985727"] = "gregorian", ["Q11184"] = "julian", ["Q1985786"] = "julian"}
		local calendar_id = mw.text.split(data.calendarmodel, 'entity/')[2]
		if (timestamp < "+1582-10-15T00:00:00Z" and calendar_model[calendar_id] == "gregorian")
			or (timestamp > "+1582-10-04T00:00:00Z" and calendar_model[calendar_id] == "julian")
			then
			calendar_add = " <sup>(" .. mw.message.new('Wikibase-time-calendar-' .. calendar_model[calendar_id]):inLanguage(parameters.lang[1]):plain() .. ")</sup>"
		end
	end
	
	local function d(f, t)
		local ts = t or timestamp
		local form = type(f) == "function" and f(ts) or f -- function in i18n.datetime[precision]
		if string.sub(ts, 1, 1) == '-' then ts = '+' .. string.sub(ts, 2) end -- formatDate() only supports years from 0
		return mw.language.new(parameters.lang[1]):formatDate(form, ts)
	end
	
	local function postFormat(t)
		if post_format and mw.ustring.find(post_format, "$1") then
			return mw.ustring.gsub(post_format, "$1", t)
		end
		return t
	end
	
	local precision = data.precision or 11
	local intyear = tonumber(string.match(timestamp, "[+-](%d+)"))
	local ret = ""
	
	if precision <= 5 then -- precision is 10000 years or more
		local factor = 10 ^ ((5 - precision) + 4)
		local y2 = math.ceil(math.abs(intyear) / factor)
		local relative = mw.ustring.gsub(i18n.datetime[precision], "$1", tostring(y2))
		if post_format == i18n.datetime["bc"] then
			ret = mw.ustring.gsub(i18n.datetime.beforenow, "$1", relative)
		else
			ret = mw.ustring.gsub(i18n.datetime.afternow, "$1", relative)
		end
		local ret_number = string.match(ret, "%d+")
		if ret_number ~= nil then
			ret = mw.ustring.gsub(ret, ret_number, mw.language.new(parameters.lang[1]):formatNum(tonumber(ret_number)))
		end
	elseif precision == 6 then -- millennia
		local card = math.floor((intyear - 1) / 1000) + 1
		if mw.ustring.find(i18n.datetime[6], "$1") then
			ret = mw.ustring.gsub(i18n.datetime[6], "$1", tostring(card))
		else
			ret = d(i18n.datetime[6], string.format("%04d", tostring(card)))
		end
		ret = postFormat(ret)
	elseif precision == 7 then -- centuries
		local card = math.floor((math.abs(intyear) - 1) / 100) + 1
		if mw.ustring.find(i18n.datetime[7], "$1") then
			ret = mw.ustring.gsub(i18n.datetime[7], "$1", tostring(card))
		else
			ret = d(i18n.datetime[7], string.format("%04d", tostring(card)))
		end
		ret = postFormat(ret) .. calendar_add
	elseif precision == 8 then -- decades
		local card = math.floor(math.abs(intyear) / 10) * 10
		ret = postFormat(mw.ustring.gsub(i18n.datetime[8], "$1", tostring(card))) .. calendar_add
	elseif precision == 9 or parameters.formatting == 'Y' then -- precision is year
		ret = postFormat(tostring(intyear)) .. calendar_add
	elseif precision == 10 then -- month
		timestamp = timestamp .. " + 1 day" -- formatDate yyyy-mm-00 returns the previous month
		ret = d(i18n.datetime[10])
		ret = postFormat(ret) .. calendar_add
		ret, _ = string.gsub(ret, "([ %[])0+", "%1") -- supress leading zeros in year, optionally linked
	else -- precision 11, day
		ret = d(parameters.formatting or i18n.datetime[11])
		ret = postFormat(ret) .. calendar_add
		ret, _ = string.gsub(ret, "([ %[])0+", "%1")
	end
	return ret, timestamp
end

-- format data value entity
local function printDatavalueEntity(data, parameters)
	local entity_id = data['id']
	local entity_page = 'Special:EntityPage/' .. entity_id
	if parameters.formatting == 'raw' then
		if data['entity-type'] == 'item' then
			entityId = resolveEntityId(entity_id)
		end
		return entity_id, entity_id
	end
	local label, lang = getLabelByLangs(entity_id, parameters.lang)
	local sitelink = mw.wikibase.getSitelink(entity_id)
	local parameter = parameters.formatting
	local labelcase = label or sitelink
	if parameters.gender == 'feminineform' then
		labelcase = feminineForm(entity_id, lang) or labelcase
	end
	if parameters.case ~= 'gender' then
		labelcase = case(parameters.case, labelcase, lang, entity_id, parameters.id)
	end
	local ret1, ret2
	if parameter == 'label' then
		ret1 = labelcase or entity_id
		ret2 = labelcase or entity_id
	elseif parameter == 'sitelink' then
		ret1 = (sitelink or 'wikidata:' .. entity_page)
		ret2 = sitelink or entity_id
	elseif mw.ustring.find((parameter or ''), '$1', 1, true) then -- formatting = a pattern
		ret1 = mw.ustring.gsub(parameter, '$1', labelcase or entity_id)
		ret1 = expandBraces(ret1, parameter)
		ret2 = labelcase or entity_id
	else
		if parameter == "ucfirst" or parameter == "ucinternallink" then
			if labelcase and lang then
				labelcase = mw.language.new(lang):ucfirst(labelcase)
			end
			-- only first of a list, reset formatting for next ones
			if parameter == "ucinterlanllink" then
				parameters.formatting = 'internallink'
			else
				parameters.formatting = nil -- default format
			end
		end
		
		if sitelink then
			ret1 = '[[' .. sitelink .. '|' .. labelcase .. ']]'
			ret2 = labelcase
		elseif label and (parameter == 'internallink' or parameter == 'ucinternallink') then
			ret1 = '[[' .. label .. '|' .. labelcase .. ']]'
			ret2 = labelcase
		else
			ret1 = '[[wikidata:' .. entity_page .. '|' .. (labelcase or entity_id) .. ']]'
			ret2 = labelcase or entity_id
		end
	end
	
	return ret1 .. addLabelIcon(entity_id, lang, parameters.lang[1], parameters.editicon), ret2
end

-- format data value monolingualtext
local function printDatavalueMonolingualText(data, parameters)
	-- data fields: language [string], text [string]
	
	if parameters.list == "lang" and data["language"] ~= parameters.lang[1] then
		return
	elseif parameters.formatting == "language" or parameters.formatting == "text" then
		return data[parameters.formatting]
	end
	local result = data["text"]
	if data["language"] ~= wiki.langcode then
		result = mw.ustring.gsub('<span lang="$1">$2</span>', '$[12]', {["$1"]=data["language"], ["$2"]=data["text"]})
	end
	if mw.ustring.find((parameters.formatting or ''), '$', 1, true) then
		-- output format defined with $text, $language
		result = mw.ustring.gsub(parameters.formatting, '$text', result)
		result = mw.ustring.gsub(result, '$language', data["language"])
	end
	return result
end

local function printError(key)
	return '<span class="error">' .. i18n.errors[key] .. '</span>'
end

-- the "qualifiers" and "snaks" field have a respective "qualifiers-order" and "snaks-order" field
-- use these as the second parameter and this function instead of the built-in "pairs" function
-- to iterate over all qualifiers and snaks in the intended order.
local function orderedpairs(array, order)
	if not order then return pairs(array) end

	-- return iterator function
	local i = 0
	return function()
		i = i + 1
		if order[i] then
			return order[i], array[order[i]]
		end
	end
end

function findClaims(entityId, property)
	if not property or not entityId then return end
	
	if not mw.ustring.match(property, "^P%d+$") then
		-- get property id for the given label
		property = mw.wikibase.resolvePropertyId(property)
		if not property then return end
	end
	local claims = mw.wikibase.getAllStatements(entityId, property)
	if #claims == 0 then
		claims = nil
	end
	return claims
end

local function getSnakValue(snak, parameters)
	if snak.snaktype == 'value' then
		-- call the respective snak parser
		if snak.datatype == 'math' then
			return printDatatypeMath(snak.datavalue.value)
		elseif snak.datatype == 'musical-notation' then
			return printDatatypeMusical(snak.datavalue.value, parameters.formatting)
		elseif snak.datatype == "url" then
			return printDatatypeUrl(snak.datavalue.value, parameters)
		elseif snak.datavalue.type == "string" then
			return printDatavalueString(snak.datavalue.value, parameters)
		elseif snak.datavalue.type == "globecoordinate" then
			return printDatavalueCoordinate(snak.datavalue.value, parameters.formatting)
		elseif snak.datavalue.type == "quantity" then
			return printDatavalueQuantity(snak.datavalue.value, parameters)
		elseif snak.datavalue.type == "time" then
			return printDatavalueTime(snak.datavalue.value, parameters)
		elseif snak.datavalue.type == 'wikibase-entityid' then
			return printDatavalueEntity(snak.datavalue.value, parameters)
		elseif snak.datavalue.type == 'monolingualtext' then
			return printDatavalueMonolingualText(snak.datavalue.value, parameters)
		end
	elseif snak.snaktype == 'novalue' then
		if parameters.formatting == 'raw' then return end
		return mw.message.new('Wikibase-snakview-snaktypeselector-novalue'):inLanguage(parameters.lang[1]):plain()
	elseif snak.snaktype == 'somevalue' then
		if parameters.formatting == 'raw' then return end
		return mw.message.new('Wikibase-snakview-snaktypeselector-somevalue'):inLanguage(parameters.lang[1]):plain()
	end
	return mw.wikibase.renderSnak(snak)
end

local function getQualifierSnak(claim, qualifierId, parameters)
	-- a "snak" is Wikidata terminology for a typed key/value pair
	-- a claim consists of a main snak holding the main information of this claim,
	-- as well as a list of attribute snaks and a list of references snaks
	if qualifierId then
		-- search the attribute snak with the given qualifier as key
		if claim.qualifiers then
			local qualifier = claim.qualifiers[qualifierId]
			if qualifier then
				if qualifier[1].datatype == "monolingualtext" then
					-- iterate over monolingualtext qualifiers to get local language
					for idx in pairs(qualifier) do
						if qualifier[idx].datavalue.value and qualifier[idx].datavalue.value.language == parameters.lang[1] then
							return qualifier[idx]
						end
					end
				elseif parameters.list then
					return qualifier
				else
					return qualifier[1]
				end
			end
		end
		return nil, printError("qualifier-not-found")
	else
		-- otherwise return the main snak
		return claim.mainsnak
	end
end

function getValueOfClaim(claim, qualifierId, parameters)
	local error
	local snak
	snak, error = getQualifierSnak(claim, qualifierId, parameters)
	if not snak then
		return nil, nil, error
	elseif snak[1] then -- a multi qualifier
		local result = {}
		local sortkey = {}
		for idx in pairs(snak) do
			result[#result + 1], sortkey[#sortkey + 1] = getSnakValue(snak[idx], parameters)
		end
		return mw.text.listToText(result, parameters.qseparator, parameters.qconjunction), sortkey[1]
	else -- a property or a qualifier
		return getSnakValue(snak, parameters)
	end
end

local function getValueOfParentClaim(claim, qualifierId, parameters)
	local qids = mw.text.split(qualifierId, '/', true)
	local valueraw, parent_claims, value, sortkey
	if qids[1] == parameters.property then
		valueraw, _, _ = getValueOfClaim(claim, nil, {["formatting"]="raw", ["lang"]=parameters.lang})
	else
		valueraw, _, _ = getValueOfClaim(claim, qids[1], {["formatting"]="raw", ["lang"]=parameters.lang})
	end
	if string.sub(valueraw or '', 1, 1) == "Q" then -- protection for 'no value'
		parent_claims = mw.wikibase.getBestStatements(valueraw, qids[2])
		if parent_claims[1] ~= nil then
			value, sortkey, _ = getValueOfClaim(parent_claims[1], nil, parameters)
			-- raw parent value needed for while/black lists, lang for avoiding an error on types other than entity
			valueraw, _, _ = getValueOfClaim(parent_claims[1], nil, {["formatting"]="raw", ["lang"]=parameters.lang})
		end
	end
	return value, sortkey, valueraw
end

local function getReferences(claim)
	local refaliases = {
		citeWeb			= "Q5637226",
		author			= "P50",
		publisher		= "P123",
		importedFrom	= "P143",
		statedIn		= "P248",
		pages			= "P304",
		publicationDate	= "P577",
		startTime		= "P580",
		endTime			= "P582",
		chapter			= "P792",
		retrieved		= "P813",
		referenceURL	= "P854",
		archiveURL		= "P1065",
		title			= "P1476",
		quote			= "P1683",
		shortName		= "P1813",
		language		= "P2439",
		archiveDate		= "P2960"
	}
	local result = ""
	-- traverse through all references
	for ref in pairs(claim.references or {}) do
		local refparts
		local refs = {}
		-- traverse through all parts of the current reference
		for snakkey, snakval in pairs(claim.references[ref].snaks or {}) do
			if snakkey ~= refaliases.importedFrom then -- "imported from" is not a proper reference
				for snakidx = 1, #snakval do
					if snakidx > 1 then refparts = refparts .. ", " end
					refparts = refparts or '' .. getSnakValue(snakval[snakidx], {lang={wiki.langcode}})
				end
				refs[snakkey] = refparts
				refparts = nil
			end
		end
		
		-- get title of general template for citing web references
		local template = mw.wikibase.getSitelink(refaliases.citeWeb) or ""
		template = mw.text.split(template, ":")[2] -- split off namespace from front
		
		-- (1) if both "reference URL" and "title" are present, then use the general template for citing web references
		if refs[refaliases.referenceURL] and (refs[refaliases.title] or refs[refaliases.statedIn]) and template then
			local citeParams = {}
			citeParams[i18n['cite']['url']] = refs[refaliases.referenceURL]
			citeParams[i18n['cite']['title']] = refs[refaliases.title] or refs[refaliases.statedIn]:match("^%[%[.-|(.-)%]%]")
			citeParams[i18n['cite']['website']] = refs[refaliases.statedIn]
			citeParams[i18n['cite']['language']] = refs[refaliases.language]
			citeParams[i18n['cite']['date']] = refs[refaliases.publicationDate]
			citeParams[i18n['cite']['access-date']] = refs[refaliases.retrieved]
			citeParams[i18n['cite']['archive-url']] = refs[refaliases.archiveURL]
			citeParams[i18n['cite']['archive-date']] = refs[refaliases.archiveDate]
			citeParams[i18n['cite']['publisher']] = refs[refaliases.publisher]
			citeParams[i18n['cite']['quote']] = refs[refaliases.quote]
			citeParams[i18n['cite']['pages']] = refs[refaliases.pages]
			citeParams[i18n['cite']['author']] = refs[refaliases.author]
			refparts = mw.getCurrentFrame():expandTemplate{title=template, args=citeParams}
		else
			-- raw ouput
			for k, v in orderedpairs(refs or {}, claim.references[ref]["snaks-order"]) do
				if k and v then
					if refparts then refparts = refparts .. ", " else refparts = "" end
					refparts = refparts .. tostring(mw.wikibase.getLabel(k)) .. ": "
					refparts = refparts .. v
				end
			end
		end
		if refparts then result = result .. mw.getCurrentFrame():extensionTag("ref", refparts) end
	end
	return result
end

-- Set whitelist or blacklist values
local function setWhiteOrBlackList(type_list, num_qual, args)
	local listed = false
	local list = {}
	for i = 0, num_qual do
		if isSet(args[type_list .. i]) then
			listed = true
			list[tostring(i)] = {}
			local values = mw.text.split(args[type_list .. i], "/", true)
			for _, v in ipairs(values) do
				list[tostring(i)][v] = true
				list[tostring(i)][resolveEntityId(v)] = true
			end
		end
	end
	return list, listed
end

local function tableParameters(args, parameters, column)
	local column_params = mw.clone(parameters)
	column_params.formatting = args["colformat"..column]; if column_params.formatting == "" then column_params.formatting = nil end
	column_params.convert = args["convert" .. column]
	if args["case" .. column] then
		column_params.case = args["case" .. column]
	end
	return column_params
end

-- Main function claim ---------------------------------------------
-- on debug console use: =p.claim{item="Q...", property="P...", ...}
function p.claim(frame)
	local args = frame.args or frame -- via invoke or require
	--If a value is already set, use it
	if isSet(args.value) then
		if args.value == 'NONE' then
			return
		else
			return args.value
		end
	end
	
	-- arguments
	local pargs = frame.args and frame:getParent().args
	local id = args.item or (pargs and pargs.item)
	if not isSet(id) then
		id = mw.wikibase.getEntityIdForCurrentPage()
		if id == nil then return end
	end
	local property = string.upper(args.property or "")
	local qualifierId = {}
	qualifierId[1] = isSet(args.qualifier) and string.upper(args.qualifier) or nil
	local i = 2
	while isSet(args["qualifier" .. i]) do
		qualifierId[i] = string.upper(args["qualifier" .. i])
		i = i + 1
	end
	local formatting = args.formatting; if formatting == "" then formatting = nil end
	local convert = args.convert; if convert == "" then convert = nil end
	if convert and string.sub(convert, 1, 1) ~= "Q" then convert = nil end
	local case = args.case
	local list = args.list or true; if (list == "false" or list == "no") then list = false end
	local sorting_col = args.tablesort
	local sorting_up = (args.sorting or "") ~= "-1"
	local separator = args.separator
	local conjunction = args.conjunction or args.separator
	local rowformat = args.rowformat
	local references = args.references
	local showerrors = args.showerrors
	local default = args.default
	if default then showerrors = nil end
	local editicon = not (args.editicon == "false" or args.editicon == "no")
	
	local parameters = {["id"] = id, ["property"] = property, ["formatting"] = formatting, ["convert"] = convert,
		["list"] = list, ["case"] = case, ["editicon"] = editicon,
		["separator"] = separator, ["conjunction"] = conjunction, ["qseparator"] = separator, ["qconjunction"] = conjunction}
	
	-- defaults for table
	local preformat, postformat = "", ""
	local whitelisted, blacklisted = false, false
	local whitelist, blacklist = {}, {}
	if parameters.formatting == "table" then
		parameters.separator = parameters.separator or "<br />"
		parameters.conjunction = parameters.conjunction or "<br />"
		parameters.qseparator = ", "
		parameters.qconjunction = ", "
		if not rowformat then
			rowformat = "$0 ($1"
			i = 2
			while qualifierId[i] do
				rowformat = rowformat .. ", $" .. i
				i = i + 1
			end
			rowformat = rowformat .. ")"
		elseif mw.ustring.find(rowformat, "^[*#]") then
			parameters.separator = "</li><li>"
			parameters.conjunction = "</li><li>"
			if mw.ustring.match(rowformat, "^[*#]") == "*" then
				preformat = "<ul><li>"
				postformat = "</li></ul>"
			else
				preformat = "<ol><li>"
				postformat = "</li></ol>"
			end
			rowformat = mw.ustring.gsub(rowformat, "^[*#] ?", "")
		end
		
		-- set whitelist and blacklist values
		whitelist, whitelisted = setWhiteOrBlackList("whitelist", #qualifierId, args)
		blacklist, blacklisted = setWhiteOrBlackList("blacklist", #qualifierId, args)
	end
	
	-- fetch property
	local claims
	for p in string.gmatch(property, 'P%d+') do
		claims = findClaims(id, p)
		if claims and claims[1] then
			break
		end
	end
	if not claims or not claims[1] then
		if showerrors then return printError("property-not-found") else return default end
	end
	
	-- find language and defaults
	parameters.lang = findLang(args.lang)
	
	-- set feminine case if gender is requested
	local itemgender = args["itemgender"]
	local idgender
	if itemgender then
		if string.match(itemgender, "^P%d+$") then
			local snak = mw.wikibase.getBestStatements(id, itemgender)[1]
			if snak and snak.mainsnak and snak.mainsnak.datavalue and snak.mainsnak.datavalue.value then
				idgender = snak.mainsnak.datavalue.value.id
			end
		elseif string.match(itemgender, "^Q%d+$") then
			idgender = itemgender
		end
	end
	local gender_requested = false
	if parameters.case == "gender" or idgender then
		gender_requested = true
	elseif parameters.formatting == "table" then
		for i=0, #qualifierId do
			if args["case" .. i] and args["case" .. i] == "gender" then
				gender_requested = true
				break
			end
		end
	end
	if gender_requested then
		if feminineGender(idgender or id) then
			parameters.gender = "feminineform"
		end
	end
	
	-- get initial sort indices
	local sortindices = {}
	for idx in pairs(claims) do
		sortindices[#sortindices + 1] = idx
	end
	-- sort by claim rank
	local comparator = function(a, b)
		local rankmap = { deprecated = 2, normal = 1, preferred = 0 }
		local ranka = rankmap[claims[a].rank or "normal"] .. string.format("%08d", a)
		local rankb = rankmap[claims[b].rank or "normal"] .. string.format("%08d", b)
		return ranka < rankb
	end
	table.sort(sortindices, comparator)
	
	local result
	local error
	if parameters.list or parameters.formatting == "table" then
		-- convert LF to line feed, <br /> may not work on some cases
		parameters.separator = parameters.separator == "LF" and "\010" or parameters.separator
		parameters.conjunction = parameters.conjunction == "LF" and "\010" or parameters.conjunction
		-- i18n separators
		parameters.separator = parameters.separator or mw.message.new('Comma-separator'):inLanguage(parameters.lang[1]):plain()
		parameters.conjunction = parameters.conjunction or (mw.message.new('And'):inLanguage(parameters.lang[1]):plain() .. mw.message.new('Word-separator'):inLanguage(parameters.lang[1]):plain())
		-- iterate over all elements and return their value (if existing)
		local value, valueq
		local sortkey, sortkeyq
		local values = {}
		local sortkeys = {}
		local refs = {}
		local firstrank = parameters.list == "firstrank" and claims[sortindices[1]].rank or ''
		local rowlist = {} -- rows to list with whitelist or blacklist
		for idx in pairs(claims) do
			local claim = claims[sortindices[idx]]
			local reference = {}
			if not whitelisted then rowlist[idx] = true end
			if firstrank ~= '' and firstrank ~= claim.rank then
				break
			end
			if parameters.formatting == "table" then
				local params = tableParameters(args, parameters, "0")
				value, sortkey, error = getValueOfClaim(claim, nil, params)
				if value then
					values[#values + 1] = {}
					sortkeys[#sortkeys + 1] = {}
					refs[#refs + 1] = {}
					if whitelist["0"] or blacklist["0"] then
						local valueraw, _, _ = getValueOfClaim(claim, nil, {["formatting"]="raw", ["lang"]=params.lang})
						if whitelist["0"] and whitelist["0"][valueraw or ""] then
							rowlist[#values] = true
						elseif blacklist["0"] and blacklist["0"][valueraw or ""] then
							rowlist[#values] = false
						end
					end
					for i, qual in ipairs(qualifierId) do
						local j = tostring(i)
						params = tableParameters(args, parameters, j)
						local valueq, sortkeyq, valueraw
						if qual == property then -- hack for getting the property with another formatting, i.e. colformat1=raw
							valueq, sortkeyq, _ = getValueOfClaim(claim, nil, params)
						else
							for q in mw.text.gsplit(qual, '%s*OR%s*') do
								if string.find(q, ".+/.+") then
									valueq, sortkeyq, valueraw = getValueOfParentClaim(claim, q, params)
								elseif string.find(q, "^/.+") then
									local claim2 = findClaims(id, string.sub(q, 2))
									if claim2 then
										valueq, sortkeyq, _ = getValueOfClaim(claim2[1], nil, params)
									end
								else
									valueq, sortkeyq, _ = getValueOfClaim(claim, q, params)
								end
								if valueq then break end
							end
						end
						values[#values]["col" .. j] = valueq
						sortkeys[#sortkeys]["col" .. j] = sortkeyq or valueq
						if whitelist[j] or blacklist[j] then
							valueq = valueraw or getValueOfClaim(claim, qual, {["formatting"]="raw", ["lang"]=params.lang})
							if whitelist[j] and whitelist[j][valueq or ""] then
								rowlist[#values] = true
							elseif blacklist[j] and blacklist[j][valueq or ""] then
								rowlist[#values] = false
							end
						end
					end
				end
			else
				value, sortkey, error = getValueOfClaim(claim, qualifierId[1], parameters)
				values[#values + 1] = {}
				sortkeys[#sortkeys + 1] = {}
				refs[#refs + 1] = {}
			end
			if not value and showerrors then value = error end
			if value then
				if references and claim.references then reference = claim.references end
				refs[#refs]["col0"] = reference
				values[#values]["col0"] = value
				sortkeys[#sortkeys]["col0"] = sortkey or value
			end
		end
		-- sort and format results
		sortindices = {}
		for idx in pairs(values) do
			sortindices[#sortindices + 1] = idx
		end
		if sorting_col then
			local sorting_table = mw.text.split(sorting_col, '/', true)
			local comparator = function(a, b)
				local valuea, valueb
				local i = 1
				while valuea == valueb and i <= #sorting_table do
					valuea = sortkeys[a]["col" .. sorting_table[i]] or ''
					valueb = sortkeys[b]["col" .. sorting_table[i]] or ''
					i = i + 1
				end
				
				if sorting_up then
					return valueb > valuea
				end
				return valueb < valuea
			end
			table.sort(sortindices, comparator)
		end
		result = {}
		for idx in pairs(values) do
			local valuerow = values[sortindices[idx]]
			local reference = getReferences({["references"] = refs[sortindices[idx]]["col0"]})
			
			value = valuerow["col0"]
			if parameters.formatting == "table" then
				if not rowlist[sortindices[idx]] then
					value = nil
				else
					value = mw.ustring.gsub(rowformat .. "$", "$0", value) -- fake end character added for easy gsub
					value = mw.ustring.gsub(value, "$R0", reference) -- add reference
					local rowformatting = rowformat .. "$"
					for i, _ in ipairs(qualifierId) do
						local valueq = valuerow["col" .. i]
						if args["rowsubformat" .. i] and valueq then
							-- add fake end character $
							-- gsub $i not followed by a number so $1 doesn't match $10, $11...
							-- remove fake end character
							valueq = mw.ustring.gsub(args["rowsubformat" .. i] .. "$", "$" .. i .. "(%D)", valueq .. "%1")
							valueq = string.sub(valueq, 1, -2)
							rowformatting = mw.ustring.gsub(rowformatting, "$" .. i .. "(%D)", args["rowsubformat" .. i] .. "%1")
						end
						valueq = valueq and urlEscapes(valueq) or ''
						value = mw.ustring.gsub(value, "$" .. i .. "(%D)", valueq .. "%1")
					end
					value = string.sub(value, 1, -2) -- remove fake end character
					value = expandBraces(value, rowformatting)
				end
			elseif value then
				value = expandBraces(value, parameters.formatting)
				value = value .. reference
			end
			if isSet(value) then
				result[#result + 1] = value
			end
			if not parameters.list then
				break
			end
		end
		result = preformat .. mw.text.listToText(result, parameters.separator, parameters.conjunction) .. postformat
	else
		-- return first element
		local claim = claims[sortindices[1]]
		result, _, error = getValueOfClaim(claim, qualifierId[1], parameters)
		if result and references then result = result .. getReferences(claim) end
	end
	
	if isSet(result) then
		return result
	else
		if showerrors then return error else return default end
	end
end

-- This is used to get the TA98 (Terminologia Anatomica first edition 1998) values like 'A01.1.00.005' (property P1323)
-- which are then linked to http://www.unifr.ch/ifaa/Public/EntryPage/TA98%20Tree/Entity%20TA98%20EN/01.1.00.005%20Entity%20TA98%20EN.htm
-- uses the newer mw.wikibase calls instead of directly using the snaks
-- formatPropertyValues returns a table with the P1323 values concatenated with ", " so we have to split them out into a table in order to construct the return string
p.getTAValue = function(frame)
	local ent = mw.wikibase.getEntity()
	local props = ent:formatPropertyValues('P1323')
	local out = {}
	local t = {}
	for k, v in pairs(props) do
		if k == 'value' then
			t = mw.text.split( v, ", ")
			for k2, v2 in pairs(t) do
				out[#out + 1] = "[http://www.unifr.ch/ifaa/Public/EntryPage/TA98%20Tree/Entity%20TA98%20EN/" .. string.sub(v2, 2) .. "%20Entity%20TA98%20EN.htm " .. v2 .. "]"
			end
		end
	end
	local ret = table.concat(out, "<br> ")
	if #ret == 0 then
		ret = "Invalid TA"
	end
	return ret
end

-- Local functions for getParentValues -----------------------

local function uc_first(word)
	return mw.ustring.upper(mw.ustring.sub(word, 1, 1)) .. mw.ustring.sub(word, 2)
end

local function getPropertyValue(id, property, parameter, langs, editicon, case)
	local snaks = mw.wikibase.getBestStatements(id, property)
	local mysnak
	if snaks and snaks[1] and snaks[1].mainsnak then
		mysnak = snaks[1].mainsnak
	else
		return
	end
	
	local entity_id
	local result = '-' -- default for 'no value'
	if mysnak.datavalue then
		entity_id = "Q" .. tostring(mysnak.datavalue.value['numeric-id'])
		result, _ = getSnakValue(mysnak, {formatting=parameter, lang=langs, editicon=editicon, case=case})
	end
	
	return entity_id, result
end

local function contains(tab, val)
	for index, value in ipairs(tab) do
		if value == val then
			return true
		end
	end
	
	return false
end

local function getParentObjects(id,
	formatting,
	languages, 
	propertySupString, 
	propertyLabel,
	propertyLink,
	labelShow,
	editicon,
	upto,
	upto_linkId,
	last_only,
	grammatical_case,
	include_self)
	
	if (upto_linkId == nil) then upto_linkId = "" end
	local upto_link_ids = mw.text.split(upto_linkId, '[/%s]+')
	local propertySups = mw.text.split(propertySupString, '[/%s]+')
	
	local lastlabel = uc_first(upto or '')
	local maxloop = tonumber(upto) or (lastlabel == '' and 10 or 50)
	
	local labelFilter = {}
	if labelShow then
		for i, v in ipairs(mw.text.split(labelShow, "/")) do
			labelFilter[uc_first(v)] = true
		end
	end
	
	local label_self
	_, label_self = getPropertyValue(id, propertyLabel, "label", languages)
	
	local result = {}
	
	local label, link, linktext
	
	for iter = 1, maxloop do
		local label, link
		for _, propertySup in pairs(propertySups) do 	
			_id, _link = getPropertyValue(id, propertySup, formatting, languages, editicon, grammatical_case)		
			if _id and _link then id = _id link = _link break end 
		end
		
		if not id or not link then break end
		
		if propertyLink then
			_, linktext = getPropertyValue(id, propertyLink, "label", languages)
			if linktext then
				link = mw.ustring.gsub(link, "%[%[(.*)%|.+%]%]", "[[%1|" .. linktext .. "]]")
			end
		end
		
		_, label = getPropertyValue(id, propertyLabel, "label", languages, editicon, "infoboxlabel")
		
		if labelShow == nil or labelFilter[label] then
			result[#result + 1] = {label, link}
			
			if label then 
				labelFilter[label] = nil -- only first label found
			end
		end
		
		if not tonumber(upto) and label == lastlabel then
			break
		end
		
		if contains(upto_link_ids, id) then
			break
		end
	end
	
	if last_only then
		result = {result[#result]}
	end
	
	if include_self then table.insert(result, 1, {label_self, mw.title.getCurrentTitle().text}) end
	
	return result
end

local function parentObjectsToString(result,
	rowformat,
	separator, 
	cascade,
	sorting)
	
	local ret = {}
	local first = 1
	local last = #result
	local iter = 1
	if sorting == "-1" then first = #result; last = 1; iter = -1 end
	for i = first, last, iter do
		local rowtext = mw.ustring.gsub(rowformat, "$[01]", {["$0"] = result[i][1], ["$1"] = result[i][2]})
		ret[#ret +1] = expandBraces(rowtext, rowformat)
	end
	
	if cascade then
		local prefix = ""
		for i = 1, #ret do
			ret[i] = prefix .. "• " .. ret[i]
			prefix = prefix .. "&nbsp;"
		end
	end
	
	return mw.text.listToText(ret, separator, separator)
end

-- Returns pairs of instance label and property value fetching a recursive tree
function p.getParentValues(frame)
	local args = frame.args or frame -- via invoke or require
	local pargs = frame.args and frame:getParent().args
	local id = args.item or (pargs and pargs.item)
	if not isSet(id) then
		id = mw.wikibase.getEntityIdForCurrentPage()
		if id == nil then return end
	end
	local languages = findLang(args.lang)
	local propertySup = args["property"]; if not isSet(propertySup) then propertySup = "P131" end --administrative entity
	local propertyLabel = args["label"]; if not isSet(propertyLabel) then propertyLabel = "P31" end --instance
	local propertyLink = args["valuetext"]; if propertyLink == "" then propertyLink = nil end --internallink
	local upto = args["upto"]; if upto == "" then upto = nil end
	local last_only = (args.last_only == "true" or args.last_only == "yes")
	local labelShow = args["labelshow"]; if labelShow == "" then labelShow = nil end
	local editicon = not (args.editicon == "false" or args.editicon == "no")
	local include_self = (args.include_self == "true" or args.include_self == "yes")
	local case = args["case"]; if case == "" then case = nil end
	
	if isSet(args.uptolabelid) then
		upto = mw.wikibase.getLabel(args.uptolabelid)
	end
	
	if isSet(args.showlabelid) then
		local showLabelList = {} for substring in mw.text.gsplit(args.showlabelid, '[/%s]+') do table.insert(showLabelList, mw.wikibase.getLabel(substring)) end
		if #showLabelList > 0 then
			labelShow = table.concat(showLabelList,"/")
		end
	end
	
	local result = getParentObjects(id,
		args.formatting,
		languages, 
		propertySup, 
		propertyLabel,
		propertyLink,
		labelShow,
		editicon,
		upto,
		args.uptolinkid,
		last_only,
		case,
		include_self)
	
	local rowformat = args["rowformat"]; if not isSet(rowformat) then rowformat = "$0 = $1" end
	local separator = args["separator"]; if not isSet(separator) then separator = "<br />" end
	local sorting = args["sorting"]; if sorting == "" then sorting = nil end
	local cascade = (args.cascade == "true" or args.cascade == "yes")
	
	return parentObjectsToString(result,
		rowformat,
		separator,
		cascade,
		sorting)
end

-- Link with a parent label --------------------
function p.linkWithParentLabel(frame)
	local args = {}
	if frame.args then
		for k, v in pairs(frame.args) do -- metatable
			args[k] = v
		end
	else
		args = frame -- via require
	end
	if isSet(args.value) then
		return args.value
	end
	
	-- get internal link of property/qualifier
	local largs = mw.clone(args)
	largs.list = "true"
	largs.formatting = "internallink"
	largs.separator = "/·/"
	largs.editicon = "false"
	local link_list = p.claim(args)
	if not isSet(link_list) then
		return
	end
	local link_table = mw.text.split(link_list, "/·/", true)
	
	-- get id value of property/qualifier
	largs.formatting = "raw"
	local items_list = p.claim(largs)
	local items_table = mw.text.split(items_list, "/·/", true)
	
	-- get label of parent property
	local parent_claims = findClaims(items_table[1], args.parent)
	if parent_claims and parent_claims[1].mainsnak.datatype == 'monolingualtext' then
		largs.formatting = nil
		largs.list = 'lang'
	else
		largs.formatting = "label"
		largs.list = "false"
	end
	largs.property = args.parent
	largs.qualifier = nil
	for i, v in ipairs(items_table) do
		largs.item = v
		local link_label = p.claim(largs)
		if isSet(link_label) then
			link_table[i] = mw.ustring.gsub(link_table[i] or '', "%[%[(.*)%|.+%]%]", "[[%1|" .. link_label .. "]]")
		end
	end
	args.editicon = not (args.editicon == "false" or args.editicon == "no")
	args.id = args.item or mw.wikibase.getEntityIdForCurrentPage()
	args.lang = findLang(args.lang)
	return mw.text.listToText(link_table)
end

-- Calculate number of years old ----------------------------
function p.yearsOld(frame)
	local args = frame.args or frame -- via invoke or require
	local id = args.item
	if not isSet(id) then
		id = mw.wikibase.getEntityIdForCurrentPage()
	end
	local lang = mw.language.new('en')
	
	local function getBestValue(id, prop)
		local snak = mw.wikibase.getBestStatements(id, prop)[1]
		if snak and snak.mainsnak and snak.mainsnak.datavalue and snak.mainsnak.datavalue.value then
			return snak.mainsnak.datavalue.value
		end
	end
	
	local birth = getBestValue(id, 'P569')
	if type(birth) ~= 'table' or birth.time == nil or birth.precision == nil or birth.precision < 8 then
		return
	end
	local death = getBestValue(id, 'P570')
	if type(death) ~= 'table' or death.time == nil or death.precision == nil then
		death = {['time'] = lang:formatDate('c'), ['precision'] = 11} -- current date
	elseif death.precision < 8 then
		return
	end
	
	local dates = {}
	dates[1] = {['min'] = {}, ['max'] = {}, ['precision'] = birth.precision}
	dates[1].min.year = tonumber(mw.ustring.match(birth.time, "^[+-]?%d+"))
	dates[1].min.month = tonumber(mw.ustring.match(birth.time, "\-(%d%d)\-"))
	dates[1].min.day = tonumber(mw.ustring.match(birth.time, "\-(%d%d)T"))
	dates[1].max = mw.clone(dates[1].min)
	dates[2] = {['min'] = {}, ['max'] = {}, ['precision'] = death.precision}
	dates[2].min.year = tonumber(mw.ustring.match(death.time, "^[+-]?%d+"))
	dates[2].min.month = tonumber(mw.ustring.match(death.time, "\-(%d%d)\-"))
	dates[2].min.day = tonumber(mw.ustring.match(death.time, "\-(%d%d)T"))
	dates[2].max = mw.clone(dates[2].min)
	
	for i, d in ipairs(dates) do
		if d.precision == 10 then -- month
			d.min.day = 1
			local timestamp = string.format("%04d", tostring(math.abs(d.max.year)))
				.. string.format("%02d", tostring(d.max.month))
				.. "01"
			d.max.day = tonumber(lang:formatDate("j", timestamp .. " + 1 month - 1 day"))
		elseif d.precision < 10 then -- year or decade
			d.min.day = 1
			d.min.month = 1
			d.max.day = 31
			d.max.month = 12
			if d.precision == 8 then -- decade
				d.max.year = d.max.year + 9
			end
		end
	end
	
	local function age(d1, d2)
		local years = d2.year - d1.year
		if d2.month < d1.month or (d2.month == d1.month and d2.day < d1.day) then
			years = years - 1
		end
		if d2.year > 0 and d1.year < 0 then
			years = years - 1 -- no year 0
		end
		return years
	end
	
	local old_min = age(dates[1].max, dates[2].min)
	local old_max = age(dates[1].min, dates[2].max)
	local old, old_expr
	if old_min == 0 and old_max == 0 then
		old = "< 1"
		old_max = 1 -- expression in singular
	elseif old_min == old_max then
		old = old_min
	else
		old = old_min .. "/" .. old_max
	end
	if args.formatting == 'unit' then
		local langs = findLang(args.lang)
		local yo, yo_sg, yo_pl, yo_pau
		if langs[1] == wiki.langcode then
			yo_sg = i18n["years-old"].singular
			yo_pl = i18n["years-old"].plural
			yo_pau = i18n["years-old"].paucal
		end
		if not isSet(yo_pl) then
			yo_pl = getLabelByLangs('Q24564698', langs)
			yo_sg = yo_pl
		end
		if not isSet(yo_pau) then
			yo_pau = yo_pl
		end
		yo = mw.language.new(langs[1]):plural(old_max, {yo_sg, yo_pau, yo_pl})
		if mw.ustring.find(yo, '$1', 1, true) then
			old_expr = mw.ustring.gsub(yo, "$1", old)
		else
			old_expr = old .. '&nbsp;' .. yo
		end
	elseif args.formatting then
		old_expr = expandBraces(mw.ustring.gsub(args.formatting, '$1', old), args.formatting)
	else
		old_expr = old
	end
	
	return old_expr
end

-- Gets a label in a given language (content language by default) or its fallbacks, optionnally linked.
function p.getLabel(frame)
	local args = frame.args or frame -- via invoke or require
	local id = mw.text.trim(args[1] or "")
	if not isSet(id) then return end
	local editicon = not (args.editicon == "false" or args.editicon == "no") and mw.wikibase.isValidEntityId(id)
	
	local label_icon = ''
	local label, lang
	if args.label then
		label = args.label
	else
		local languages = findLang(args.lang)
		-- exceptions or labels fixed
		local exist, labels = pcall(require, wiki.module_title .. "/labels" .. (languages[1] == wiki.langcode and '' or '/' .. languages[1]))
		if exist and next(labels.infoboxLabelsFromId) ~= nil then
			label = labels.infoboxLabelsFromId[id]
		end
		
		if label == nil then
			local new_id = resolveEntityId(id)
			if new_id then
				label, lang = getLabelByLangs(new_id, languages)
				if label then
					if args.itemgender and feminineGender(args.itemgender) then
						label = feminineForm(new_id, lang) or label
					end
					label = mw.language.new(lang):ucfirst(mw.text.nowiki(label)) -- sanitize
				end
				label_icon = addLabelIcon(new_id or id, lang, languages[1], editicon)
			end
		end
	end
	
	local linked = args.linked
	if isSet(linked) and linked ~= "no" then
		local article = mw.wikibase.getSitelink(id) or ("d:" .. id)
		return "[[" .. article .. "|" .. (label or id) .. "]]" .. label_icon
	else
		return (label or id) .. label_icon
	end
end

-- Utilities -----------------------------

-- debugging functions, see module ../debug.
function p.ViewSomething(frame)
	return require(wiki.module_title .. "/debug").ViewSomething(frame)
end

function p.Dump(frame)
	return require(wiki.module_title .. "/debug").Dump(frame)
end

function p.getEntityFromTree(frame)
	return require(wiki.module_title .. "/debug").getEntityFromTree(frame)
end

-- Copied from Module:Wikibase
function p.getSiteLink(frame)
	local id = frame.args[1]
	if not isSet(id) then
		id = mw.wikibase.getEntityIdForCurrentPage()
		if id == nil then
			return
		end
	end
	return mw.wikibase.getSitelink(id, frame.args[2])
end

-- Helper function for the default language code used
function p.lang(frame)
	local lang = frame and frame.args[1] -- nil via require
	return findLang(lang)[1]
end

-- Number of statements
function p.numStatements(frame)
	local args = frame.args
	local id = args.item
	if id == '' or id == nil then
		id = mw.wikibase.getEntityIdForCurrentPage()
		if id == nil then
			return 0
		end
	end
	local prop = mw.text.trim(args[1])
	local num = mw.wikibase.getBestStatements(id, prop)
	return #num
end

-- Returns the first id or value of given property or nil if not found, not isValidEntityId or novalue/somevalue
-- See Module:Wikibase
function p.validProperty(frame)
	local property = mw.text.trim(frame.args[1])
	local item = frame.args.item or frame.args.from; if item == '' then item = nil end
	local type = frame.args.type or "id"
	local entity = mw.wikibase.getEntity(item)
	if not entity then return end
	if not entity.claims then return end
	local hasProp = entity.claims[property]
	if not hasProp then return end
	if not hasProp[1].mainsnak.datavalue then return end
	if type == "value" then return hasProp[1].mainsnak.datavalue.value end
	if not hasProp[1].mainsnak.datavalue.value.id then return end
	if not mw.wikibase.isValidEntityId(hasProp[1].mainsnak.datavalue.value.id) then return end
	return hasProp[1].mainsnak.datavalue.value.id
end

return p