Module:WikidataIB

From Random Island Wiki
Revision as of 20:35, 14 June 2018 by >Pppery (If you insist on reverting me here, at least don't reinstate the bug that causes getValue to ignore local parameters for pages with no Wikidata item)
Jump to navigation Jump to search

Documentation for this module may be created at Module:WikidataIB/doc

-- Module to implement use of a blacklist and whitelist for infobox fields
-- Can take a named parameter |qid which is the Wikidata ID for the article
-- if not supplied, it will use the Wikidata ID associated with the current page.
-- Fields in blacklist are never to be displayed, i.e. module must return nil in all circumstances
-- Fields in whitelist return local value if it exists or the Wikidata value otherwise
-- The name of the field that this function is called from is passed in named parameter |name
-- The name is compulsory when blacklist or whitelist is used,
-- so the module returns nil if it is not supplied.
-- blacklist is passed in named parameter |suppressfields (or |spf)
-- whitelist is passed in named parameter |fetchwikidata (or |fwd)

local p = {}

local i18n =
{
	["errors"] =
	{
		["property-not-found"] = "Property not found.",
		["No property supplied"] = "No property supplied",
		["entity-not-found"] = "Wikidata entity not found.",
		["unknown-claim-type"] = "Unknown claim type.",
		["unknown-entity-type"] = "Unknown entity type.",
		["qualifier-not-found"] = "Qualifier not found.",
		["site-not-found"] = "Wikimedia project not found.",
		["unknown-datetime-format"] = "Unknown datetime format.",
		["local-article-not-found"] = "Article is available on Wikidata, but not on Wikipedia",
		["dab-page"] = " (dab)",
	},
	["months"] =
	{
		"January", "February", "March", "April", "May", "June", "July",
		"August", "September", "October", "November", "December"
	},
	["century"] = "century",
	["BC"] = "BC",
	["BCE"] = "BCE",
	["ordinal"] =
	{
		[1] = "st",
		[2] = "nd",
		[3] = "rd",
		["default"] = "th"
	},
	["filespace"] = "File",
	["Unknown"] = "Unknown",
	["NaN"] = "Not a number",
	["editonwikidata"] = "Edit this on Wikidata",
	["latestdatequalifier"] = function (date) return "before " .. date end,
	-- some languages, e.g. Bosnian use a period as a suffix after each number in a date
	["datenumbersuffix"] = "",
	["list separator"] = ", ",
	["abbr"] =
	{
		["Q828224"]  = "km",
		["Q11573"]   = "m",
		["Q174728"]  = "cm",
		["Q174789"]  = "mm",
		["Q712226"]  = "sq km",
		["Q11570"]   = "kg",
		["Q41803"]   = "g",
		["Q3241121"] = "mg",
		["Q2332346"] = "ml",
		["Q7727"]    = "min",
		["Q11574"]   = "s",
	},
}
-- This allows a internationisation module to override the above table
require("Module:i18n").loadI18n("Module:WikidataIB/i18n", i18n)

-- This piece of html implements a collapsible container. Check the classes exist on your wiki.
local collapsediv = '<div class="mw-collapsible mw-collapsed" style="width:100%; overflow:auto;" data-expandtext="{{int:show}}" data-collapsetext="{{int:hide}}">'

-------------------------------------------------------------------------------
-- Private functions
-------------------------------------------------------------------------------
--
-------------------------------------------------------------------------------
-- makeOrdinal needs to be internationalised along with the above:
-- takes cardinal numer as a numeric and returns the ordinal as a string
-- we need three exceptions in English for 1st, 2nd, 3rd, 21st, .. 31st, etc.
-------------------------------------------------------------------------------
local function makeOrdinal(cardinal)
	local ordsuffix = i18n.ordinal.default
	if cardinal % 10 == 1 then
		ordsuffix = i18n.ordinal[1]
	elseif cardinal % 10 == 2 then
		ordsuffix = i18n.ordinal[2]
	elseif cardinal % 10 == 3 then
		ordsuffix = i18n.ordinal[3]
	end
	-- In English, 1, 21, 31, etc. use 'st', but 11, 111, etc. use 'th'
	-- similarly for 12 and 13, etc.
	if (cardinal % 100 == 11) or (cardinal % 100 == 12) or (cardinal % 100 == 13) then
		ordsuffix = i18n.ordinal.default
	end
	return tostring(cardinal) .. ordsuffix
end


-------------------------------------------------------------------------------
-- findLang takes a "langcode" parameter if supplied
-- otherwise it tries to create it from the user's set language ({{int:lang}})
-- failing that it uses the wiki's content language.
-- It returns a language object
-------------------------------------------------------------------------------
local function findLang(langcode)
	local langobj
	if not langcode or langcode == "" then
		langcode = mw.getCurrentFrame():preprocess( '{{int:lang}}' )
	end
	if mw.language.isKnownLanguageTag(langcode) then
		langobj = mw.language.new( langcode )
	else
		langobj = mw.language.getContentLanguage()
	end
	return langobj
end


-------------------------------------------------------------------------------
-- roundto takes a positive number (x)
-- and returns it rounded to (sf) significant figures
-------------------------------------------------------------------------------
local function roundto(x, sf)
	if x == 0 then return 0 end
	x = math.abs(x)
	if sf < 1 then sf = 1 end
	local e = math.floor(math.log10(x)) - sf + 1
	local m = math.floor(x / 10^e + 0.5)
	x = m * 10^e
	-- if it's integral, cast to an integer:
	if  x == math.floor(x) then x = math.floor(x) end
	return x
end


-------------------------------------------------------------------------------
-- decimalToDMS takes a decimal degrees (x) with precision (p)
-- and returns degrees/minutes/seconds according to the precision
-------------------------------------------------------------------------------
local function decimalToDMS(x, p)
	-- if p is not supplied, use a precision around 0.1 seconds
	if not tonumber(p) then p = 1e-4 end
	local d = math.floor(x)
	local ms = (x - d) * 60
	if p > 0.5 then -- precision is > 1/2 a degree
		if ms > 30 then d = d + 1 end
		ms = 0
	end
	local m = math.floor(ms)
	local s = (ms - m) * 60
	if p > 0.008 then -- precision is > 1/2 a minute
		if s > 30 then m = m +1 end
		s = 0
	elseif p > 0.00014 then -- precision is > 1/2 a second
		s = math.floor(s + 0.5)
	elseif p > 0.000014 then -- precision is > 1/20 second
		s = math.floor(10 * s + 0.5) / 10
	elseif p > 0.0000014 then -- precision is > 1/200 second
		s = math.floor(100 * s + 0.5) / 100
	else -- cap it at 3 dec places for now
		s = math.floor(1000 * s + 0.5) / 1000
	end
	return d, m, s
end


-------------------------------------------------------------------------------
-- decimalPrecision takes a decimal (x) with precision (p)
-- and returns x rounded approximately to the given precision
-- precision should be between 1 and 1e-6, preferably a power of 10.
-------------------------------------------------------------------------------
local function decimalPrecision(x, p)
	-- if p is not supplied, pick an arbitrary precision
	if not tonumber(p) then p = 1e-4 end
	if p > 1 then p = 1 end
	if p < 1e-6 then p = 1e-6 end
	local e = math.floor(math.log10(p))
	local m = math.floor(x / 10^e + 0.5)
	x = m * 10^e
	-- if it's integral, cast to an integer:
	if  x == math.floor(x) then x = math.floor(x) end
	-- if it's less than 1e-4, it will be in exponent form, so return a string with 6dp
	-- 9e-5 becomes 0.000090
	if math.abs(x) < 1e-4 then x = string.format("%f", x) end
	return x
end


-------------------------------------------------------------------------------
-- formatDate takes a datetime of the usual format from mw.wikibase.entity:formatPropertyValues
-- like "1 August 30 BCE" as parameter 1
-- and formats it according to the df (date format) and bc parameters
-- df = ["dmy" / "mdy" / "y"] default will be "dmy"
-- bc = ["BC" / "BCE"] default will be "BCE"
-------------------------------------------------------------------------------
local format_Date = function(datetime, dateformat, bc)
	local datetime = datetime or "1 August 30 BCE" -- in case of nil value
	-- chop off multiple vales and/or any hours, mins, etc.
	-- keep anything before punctuation - we just want a single date:
	local dateval = string.match( datetime, "[%w ]+")

	local dateformat = string.lower(dateformat or "dmy") -- default to dmy

	local bc = string.upper(bc or "") -- can't use nil for bc
	-- we only want to accept two possibilities: BC or default to BCE
	if bc == "BC" then
		bc = "&nbsp;" .. i18n["BC"] -- prepend a non-breaking space.
	else
		bc = "&nbsp;" .. i18n["BCE"]
	end

	local postchrist = true -- start by assuming no BCE
	local dateparts = {}
	for word in string.gmatch(dateval, "%w+") do
		if word == "BCE" or word == "BC" then -- **internationalise later**
			postchrist = false
		else
			-- we'll keep the parts that are not 'BCE' in a table
			dateparts[#dateparts + 1] = word
		end
	end
	if postchrist then bc = "" end -- set AD dates to no suffix **internationalise later**

	local sep = "&nbsp;" -- separator is nbsp
	local fdate = table.concat(dateparts, sep) -- set formatted date to same order as input

	-- if we have day month year, check dateformat
	if #dateparts == 3 then
		if dateformat == "y" then
			fdate = dateparts[3]
		elseif dateformat == "mdy" then
			fdate = dateparts[2] .. sep .. dateparts[1] .. "," .. sep .. dateparts[3]
		end
	elseif #dateparts == 2 and dateformat == "y" then
		fdate = dateparts[2]
	end

	return fdate .. bc
end


-------------------------------------------------------------------------------
-- parseParam takes a (string) parameter, e.g. from the list of frame arguments,
-- and makes "false", "no", and "0" into the (boolean) false
-- it makes the empty string and nil into the (boolean) value passed as default
-- allowing the parameter to be true or false by default.
-------------------------------------------------------------------------------
local parseParam = function(param, default)
	if param and param ~= "" then
		param = param:lower()
		if (param == "false") or (param == "no") or (param == "0") then
			return false
		else
			return true
		end
	else
		return default
	end
end


-------------------------------------------------------------------------------
-- The label in a Wikidata item is subject to vulnerabilities
-- that an attacker might try to exploit.
-- It needs to be 'sanitised' by removing any wikitext before use.
-- If it doesn't exist, return the id for the item
-- a second (boolean) value is also returned, value is true when the label exists
-------------------------------------------------------------------------------
local labelOrId = function (id)
	local label = mw.wikibase.label(id)
	if label then
		return mw.text.nowiki(label), true
	else
		return id, false
	end
end


-------------------------------------------------------------------------------
-- sourced takes a table representing a statement that may or may not have references
-- it counts how many references are sourced to something not containing the word "wikipedia"
-- it returns a boolean = true if there are any sourced references.
-------------------------------------------------------------------------------
local sourced = function(claim)
	if claim.references then
		for kr, vr in pairs(claim.references) do
			local ref = mw.wikibase.renderSnaks(vr.snaks)
			if not ref:find("Wikipedia") then
				return true
			end
		end
	end
end


-------------------------------------------------------------------------------
-- setRanks takes a flag (parameter passed) that requests the values to return
-- "b[est]" returns preferred if available, otherwise normal
-- "p[referred]" returns preferred
-- "n[ormal]" returns normal
-- "d[eprecated]" returns deprecated
-- multiple values are allowed, e.g. "preferred normal" (which is the default)
-- "best" will override the other flags, and set p and n
-------------------------------------------------------------------------------
local function setRanks(rank)
	rank = (rank or ""):lower()
	-- if nothing passed, return preferred and normal
	-- if rank == "" then rank = "p n" end
	local ranks = {}
	for w in string.gmatch(rank, "%a+") do
		w = w:sub(1,1)
		if w == "b" or w == "p" or w == "n" or w == "d" then
			ranks[w] = true
		end
	end
	-- check if "best" is requested or no ranks requested; and if so, set preferred and normal
	if ranks.b or not next(ranks) then
		ranks.p = true
		ranks.n = true
	end
	return ranks
end


-------------------------------------------------------------------------------
-- parseInput processes the Q-id , the blacklist and the whitelist
-- if an input parameter is supplied, it returns that and ends the call.
-- it returns (1) either the qid or nil indicating whether or not the call should continue
-- and (2) a table containing all of the statements for the propertyID and relevant Qid
-- if "best" ranks are requested, it returns those instead of all non-deprecated ranks
-------------------------------------------------------------------------------
local parseInput = function(frame, input_parm, property_id)
	-- There may be a local parameter supplied, if it's blank, set it to nil
	input_parm = mw.text.trim(input_parm or "")
	if input_parm == "" then input_parm = nil end

	local args = frame.args

	-- can take a named parameter |qid which is the Wikidata ID for the article.
	-- if it's not supplied, use the id for the current page
	local qid = args.qid or ""
	if qid == "" then qid = mw.wikibase.getEntityIdForCurrentPage() end
	-- if there's no Wikidata item for the current page return nil
	if not qid then return false, input_parm end

	-- The blacklist is passed in named parameter |suppressfields
	local blacklist = args.suppressfields or args.spf

	-- The whitelist is passed in named parameter |fetchwikidata
	local whitelist = args.fetchwikidata or args.fwd
	if not whitelist or whitelist == "" then whitelist = "NONE" end

	-- The name of the field that this function is called from is passed in named parameter |name
	local fieldname = args.name or ""

	if blacklist then
		-- The name is compulsory when blacklist is used, so return nil if it is not supplied
		if not fieldname or fieldname == "" then return false, nil end
		-- If this field is on the blacklist, then return nil
		if blacklist:find(fieldname) then return false, nil end
	end

	-- If we got this far then we're not on the blacklist
	-- The blacklist overrides any locally supplied parameter as well
	-- If a non-blank input parameter was supplied return it
	if input_parm then return false, input_parm end

	-- Otherwise see if this field is on the whitelist:
	-- needs a bit more logic because find will return its second value = 0 if fieldname=""
	-- but nil if fieldname not found on whitelist
	local _, found = whitelist:find(fieldname)
	found = ((found or 0) > 0)
	if whitelist ~= 'ALL' and (whitelist:upper() == "NONE" or not found) then
		return false, nil
	end

	-- See what's on Wikidata (the call always returns a table, but it may be empty):
	local props = {}
	if args.reqranks.b then
		props = mw.wikibase.getBestStatements(qid, property_id)
	else
		props = mw.wikibase.getAllStatements(qid, property_id)
	end
	if props[1] then
		return qid, props
	end
	-- no property on Wikidata
	return false, nil
end


-------------------------------------------------------------------------------
-- assembleoutput takes the sequence table containing the property values
-- and formats it according to switches given
-- it needs the entityID and propertyID to link from the pen icon
-------------------------------------------------------------------------------
-- Dependencies: parseParam
-------------------------------------------------------------------------------
local function assembleoutput(out, args, entityID, propertyID)

	-- sorted is a boolean passed to enable sorting of the values returned
	-- if nothing or an empty string is passed set it false
	-- if "false" or "no" or "0" is passed set it false
	local sorted = parseParam(args.sorted, false)

	-- noicon is a boolean passed to suppress the trailing "edit at Wikidata" icon
	-- for use when the value is processed further by the infobox
	-- if nothing or an empty string is passed set it false
	-- if "false" or "no" or "0" is passed set it false
	local noic = parseParam(args.noicon, false)

	-- list is the name of a template that a list of multiple values is passed through
	-- examples include "hlist" and "ubl"
	-- setting it to "prose" produces something like "1, 2, 3, and 4"
	local list = args.list or ""

	-- sep is a string that is used to separate multiple returned values
	-- if nothing or an empty string is passed set it to the default
	-- any double-quotes " are stripped out, so that spaces may be passed
	-- e.g. |sep=" - "
	local sepdefault = i18n["list separator"]
	local separator = args.sep or ""
	separator = string.gsub(separator, '"', '')
	if separator == "" then
		separator = sepdefault
	end

	-- collapse is a number that determines the maximum number of returned values
	-- before the output is collapsed.
	-- Zero or not a number result in no collapsing (default becomes 0).
	local collapse = tonumber(args.collapse) or 0

	-- if there's anything to return, then return a list
	-- comma-separated by default, but may be specified by the sep parameter
	-- optionally specify a hlist or ubl or a prose list, etc.
	local strout
	if #out > 0 then
		if sorted then table.sort(out) end
		-- if a pen icon is wanted add it the end of the last value
		if not noic then
			local icon = "&nbsp;[[" .. i18n["filespace"]
			icon = icon .. ":Blue pencil.svg |frameless |text-top |10px |alt="
			icon = icon .. i18n["editonwikidata"]
			icon = icon .. "|link=https://www.wikidata.org/wiki/" .. entityID
			icon = icon .. "?uselang=" .. args.langobj.code
			icon = icon .. "#" .. propertyID .. "|" .. i18n["editonwikidata"] .. "]]"
			out[#out] = out[#out] .. icon
		end
		if list == "" then
			strout = table.concat(out, separator)
		elseif list:lower() == "prose" then
			strout = mw.text.listToText( out )
		else
			strout = mw.getCurrentFrame():expandTemplate{title = list, args = out}
		end
		if collapse >0 and #out > collapse then
			strout = collapsediv .. strout .. "</div>"
		end
	else
		strout = nil -- no items had valid reference
	end
	return strout
end


-------------------------------------------------------------------------------
-- propertyvalueandquals takes a property object, the arguments passed from frame,
-- and a qualifier propertyID.
-- It returns a sequence (table) of values representing the values of that property
-- and qualifiers that match the qualifierID if supplied.
-------------------------------------------------------------------------------
-- Dependencies: parseParam; sourced; labelOrId; i18n.latestdatequalifier; format_Date;
-- makeOrdinal; roundto; decimalPrecision; decimalToDMS; assembleoutput;
-------------------------------------------------------------------------------
local function propertyvalueandquals(objproperty, args, qualID)

	-- onlysourced is a boolean passed to return only values sourced to other than Wikipedia
	-- if nothing or an empty string is passed set it true
	local onlysrc = parseParam(args.onlysourced or args.osd, true)

	-- linked is a a boolean that enables the link to a local page via sitelink
	-- if nothing or an empty string is passed set it true
	local linked = parseParam(args.linked, true)

	-- prefix is a string that may be nil, empty (""), or a string of characters
	-- this is prefixed to each value
	-- useful when when multiple values are returned
	-- any double-quotes " are stripped out, so that spaces may be passed
	local prefix = (args.prefix or ""):gsub('"', '')

	-- postfix is a string that may be nil, empty (""), or a string of characters
	-- this is postfixed to each value
	-- useful when when multiple values are returned
	-- any double-quotes " are stripped out, so that spaces may be passed
	local postfix = (args.postfix or ""):gsub('"', '')

	-- linkprefix is a string that may be nil, empty (""), or a string of characters
	-- this creates a link and is then prefixed to each value
	-- useful when when multiple values are returned and indirect links are needed
	-- any double-quotes " are stripped out, so that spaces may be passed
	local lprefix = (args.linkprefix or ""):gsub('"', '')

	-- linkpostfix is a string that may be nil, empty (""), or a string of characters
	-- this is postfixed to each value when linking is enabled with lprefix
	-- useful when when multiple values are returned
	-- any double-quotes " are stripped out, so that spaces may be passed
	local lpostfix = (args.linkpostfix or ""):gsub('"', '')

	-- wdlinks is a boolean passed to enable links to Wikidata when no article exists
	-- if nothing or an empty string is passed set it false
	local wdl = parseParam(args.wdlinks or args.wdl, false)

	-- unitabbr is a boolean passed to enable unit abbreviations for common units
	-- if nothing or an empty string is passed set it false
	local uabbr = parseParam(args.unitabbr, false)

	-- maxvals is a string that may be nil, empty (""), or a number
	-- this determines how many items may be returned when multiple values are available
	-- setting it = 1 is useful where the returned string is used within another call, e.g. image
	local maxvals = tonumber(args.maxvals) or 0

	-- all proper values of a Wikidata property will be the same type as the first
	-- qualifiers don't have a mainsnak, properties do
	local datatype = objproperty[1].datatype or objproperty[1].mainsnak.datatype
	-- out holds the values for this property
	-- mtl holds the language code if the datatype is monolingual text
	local out = {}
	local mtl = {}
	for k, v in pairs(objproperty) do
		local snak = v.mainsnak or v
		local datavalue = snak.datavalue
		datavalue = datavalue and datavalue.value
		if onlysrc and not sourced(v) then
			-- nothing added to 'out': it isn't sourced when onlysourced=true
			------------------------------------
		elseif v.rank and not args.reqranks[v.rank:sub(1, 1)] then
			-- nothing added to 'out': value has a rank that isn't requested
		elseif snak.snaktype == "somevalue" then -- value is unknown
			out[#out + 1] = i18n["Unknown"]
			------------------------------------
		elseif snak.snaktype == "novalue" then -- value is none
			-- out[#out + 1] = "No value" -- don't return anything
			------------------------------------
		elseif datatype == "wikibase-item" then -- data type is a wikibase item:
			-- it's wiki-linked value, so output as link if enabled and possible
			local qnumber = datavalue.id
			local sitelink = mw.wikibase.sitelink(qnumber)
			local label, islabel = labelOrId(qnumber)
			if linked then
				if sitelink then
					-- Check which Wiki we're on
					local site = mw.site.siteName
					-- we could also check other wikis that prefer to use label:
					if site ~= "Wikimedia Commons" then
						-- strip any namespace or dab from the sitelink
						-- and use that as label
						local pos = sitelink:find(":") or 0
						label = sitelink:sub(pos+1):gsub("%s%(.+%)$", ""):gsub(",.+$", "")
					end
					out[#out + 1] = "[[" .. lprefix .. sitelink .. lpostfix .. "|" .. label .. "]]"
				elseif islabel then
					-- no sitelink, label exists
					-- examine what an article with a title the same as the label would be
					local artitle = mw.title.new(label, 0)
					if artitle and artitle.redirectTarget then
						-- there's a redirect with the same title as the label
						-- let's link to that
						out[#out + 1] = "[[".. lprefix .. label .. lpostfix
						out[#out] = out[#out] .. "|" .. label .. "]]"
					else
						-- no sitelink, label exists, not a redirect
						-- output the plain label (optionally with Wikidata link)
						if wdl then
							-- show that there's a Wikidata entry available
							local wd = "[[:d:" .. qnumber .. "|" .. label
							wd = wd .. "]]&nbsp;<span title='"
							wd = wd .. i18n["errors"]["local-article-not-found"]
							wd = wd .. "'>[[File:Wikidata-logo.svg|16px|alt=|link=]]</span>"
							out[#out + 1] = wd
						else
							-- no wikidata links required, so just give the plain label
							out[#out + 1] = label
						end -- test if wikdata link display required
					end -- test if article title exists as redirect on current Wiki
				else
					-- no sitelink and no label
					out[#out + 1] = qnumber
				end -- test for sitelink exists
			else -- no link wanted so test for lang code
				local lang = args.lang or ""
				if lang ~= "" then
					-- there's a language code given, so look for label and sanitise it
					label = mw.text.nowiki( mw.wikibase.getLabelByLang(qnumber, lang) or label )
				end
				-- add the plain label
				out[#out + 1] = label
			end -- test for link required
			-- If the property has a qualifier of latest date, add that in all cases:
			if v.qualifiers then
				local quals = v.qualifiers["P1326"] -- latest date qualifier
				if quals then
					local ldq = i18n.latestdatequalifier(mw.wikibase.renderSnaks(quals))
					out[#out] = out[#out] .. " (" .. ldq .. ")"
				end
			end
			------------------------------------
		elseif datatype == "time" then -- data type is time:
			-- it's a date value, so output according to formatting preferences
			local timestamp = datavalue.time
			-- A year can be stored like this: "+1872-00-00T00:00:00Z",
			-- which is processed here as if it were the day before "+1872-01-01T00:00:00Z",
			-- and that's the last day of 1871, so the year is wrong.
			-- So fix the month 0, day 0 timestamp to become 1 January instead:
			timestamp = timestamp:gsub("%-00%-00T", "-01-01T")
			local dateprecision = datavalue.precision
			local fpvdate = tonumber(timestamp:sub(2, 5))
			local fdate
			if dateprecision >= 9 then -- precision is year or shorter
				local dateformat = "y"
				if dateprecision >= 10 then -- prepend month
					fpvdate = i18n.months[tonumber(timestamp:sub(7, 8))] .. " " .. fpvdate
					dateformat = args.df
					if dateprecision >= 11 then -- prepend day
							fpvdate = tonumber(timestamp:sub(10, 11)) .. " " .. fpvdate
					end
				end
				if timestamp:sub(1, 1) == "-" then
					fpvdate = fpvdate .. " BCE"
				end
				fdate = format_Date(fpvdate, dateformat, args.bc)
				-- testing the ability to add "circa" from P1480 "sourcing circumstances"
				-- just testing on years for now
				if dateprecision == 9 and v.qualifiers then
					local sc = v.qualifiers.P1480
					if sc then
						local circa = ""
						for k1, v1 in pairs(sc) do
							if v1.datavalue.value.id == "Q5727902" then
								circa = '<abbr title="circa">c.</abbr>&nbsp;'
								break
							end
						end
						fdate = circa .. fdate
					end
				end
			elseif dateprecision == 7 then -- century
				local century = math.floor((fpvdate - 1) / 100) + 1
				fdate = makeOrdinal(century) .. "&nbsp;" .. i18n["century"]
				if timestamp:sub(1, 1) == "-" then -- date is BC
					local bc = string.upper(args.bc or "") -- can't use nil for bc
					-- we only want to accept two possibilities: BC or default to BCE
					if bc == "BC" then
						fdate = fdate .. "&nbsp;" .. i18n["BC"] -- use non-breaking space.
					else
						fdate = fdate .. "&nbsp;" .. i18n["BCE"]
					end
				end
			else
				-- date precisions 0 to 6 (billion years to millenium) TODO:
				--
			end
			out[#out+1] = fdate
			------------------------------------
		-- data types which are strings:
		elseif datatype == "commonsMedia" or datatype == "external-id" or datatype == "string" or datatype == "url" then
			-- commonsMedia or external-id or string or url
			-- all have mainsnak.datavalue.value as string
			if lprefix == "" and lpostfix == "" then
				out[#out+1] = prefix .. datavalue .. postfix
			else
				out[#out+1] = "[[" .. lprefix .. datavalue .. lpostfix
				out[#out] = out[#out] .. "|" .. prefix .. datavalue .. postfix .. "]]"
			end -- check for link requested (i.e. either linkprefix or linkpostfix exists)
			------------------------------------
		-- data types which are quantities:
		elseif datatype == "quantity" then
			-- quantities have mainsnak.datavalue.value.amount and mainsnak.datavalue.value.unit
			-- the unit is of the form http://www.wikidata.org/entity/Q829073
			--
			-- get the language object as 'lang' to format the numerical value
			local lang = args.langobj
			--
			-- implement a switch to turn on/off numerical formatting later
			local fnum = true
			-- convert amount to a number
			local amount = tonumber(datavalue.amount) or i18n["NaN"]
			-- check if upper and/or lower bounds are given and significant
			local upb = tonumber(datavalue.upperBound)
			local lowb = tonumber(datavalue.lowerBound)
			if upb and lowb then
				-- differences rounded to 2 sig fig:
				local posdif = roundto(upb - amount, 2)
				local negdif = roundto(amount - lowb, 2)
				if fnum then amount = lang:formatNum( amount ) end
				if posdif ~= negdif then
					-- non-symmetrical
					amount = amount .. " +" .. posdif .. " -" .. negdif
				elseif posdif ~= 0 then
					-- symmetrical and significant
					amount = amount .. " ±" .. posdif
				else
				-- otherwise range is zero, so leave it off: amount = amount
				end
			else
				if fnum then amount = lang:formatNum( amount ) end
			end
			-- extract the qid in the form 'Qnnn' from the value.unit url
			-- and then fetch the label from that
			local unit = ""
			local unitqid = string.match( datavalue.unit, "(Q%d+)" )
			if unitqid then
				if uabbr and i18n.abbr[unitqid] then
					-- it's on the list of common abbreviations, so use that
					unit = "&nbsp;" .. i18n.abbr[unitqid]
				else
					-- otherwise use the label (i.e. unit name) if it exists
					local uname = mw.wikibase.label( unitqid )
					if uname then unit = " " .. uname end
				end
			end
			out[#out+1] = amount .. unit
			------------------------------------
		-- datatypes which are global coordinates:
		elseif datatype == "globe-coordinate" then
			-- 'display' parameter defaults to "inline, title" *** unused for now ***
			-- local disp = args.display or ""
			-- if disp == "" then disp = "inline, title" end
			--
			-- format parameter switches from deg/min/sec to decimal degrees
			-- default is deg/min/sec -- decimal degrees needs |format = dec
			local form = (args.format or ""):lower():sub(1,3)
			if form ~= "dec" then form = "dms" end
			--
			-- show parameter allows just the latitude or longitude to be shown
			local show = (args.show or ""):lower()
			if show ~= "longlat" then show = show:sub(1,3) end
			--
			local lat, long, prec = datavalue.latitude, datavalue.longitude, datavalue.precision
			if show == "lat" then
				out[#out+1] = decimalPrecision(lat, prec)
			elseif show == "lon" then
				out[#out+1] = decimalPrecision(long, prec)
			elseif show == "longlat" then
				out[#out+1] = decimalPrecision(long, prec) .. ", " .. decimalPrecision(lat, prec)
			else
				local ns = "N"
				local ew = "E"
				if lat < 0 then
					ns = "S"
					lat = - lat
				end
				if long < 0 then
					ew = "W"
					long = - long
				end
				if form == "dec" then
					lat = decimalPrecision(lat, prec)
					long = decimalPrecision(long, prec)
					out[#out+1] = lat .. "°" .. ns .. " " .. long ..  "°" .. ew
				else
					local latdeg, latmin, latsec = decimalToDMS(lat, prec)
					local longdeg, longmin, longsec = decimalToDMS(long, prec)

					if latsec == 0 and longsec == 0 then
						if latmin == 0 and longmin == 0 then
							out[#out+1] = latdeg .. "°" .. ns .. " " .. longdeg ..  "°" .. ew
						else
							out[#out+1] = latdeg .. "°" .. latmin .. "′" .. ns .. " "
							out[#out] = out[#out] .. longdeg .. "°".. longmin .. "′" .. ew
						end
					else
						out[#out+1] = latdeg .. "°" .. latmin .. "′" .. latsec .. "″" .. ns .. " "
						out[#out] = out[#out] .. longdeg .. "°" .. longmin .. "′" .. longsec .. "″" .. ew
					end
				end
			end
			------------------------------------
		elseif datatype == "monolingualtext" then -- data type is Monolingual text:
			-- has mainsnak.datavalue.value as a table containing language/text pairs
			-- collect all the values in 'out' and languages in 'mtl' and process them later
			out[#out+1] = prefix .. datavalue.text .. postfix
			mtl[#out] = datavalue.language
			------------------------------------
		else
			-- some other data type so write a specific handler
			out[#out+1] = "unknown data type: " .. datatype
		end -- of datatype/unknown value/sourced check

		-- See if qualifiers are to be returned:
		if v.qualifiers and qualID and snak.snaktype=="value" then
			local qsep = (args.qsep or ""):gsub('"', '')
			local qargs = {
				["osd"]         = "false",
				["linked"]      = tostring(linked),
				["prefix"]      = args.qprefix,
				["postfix"]     = args.qpostfix,
				["linkprefix"]  = args.qlinkprefix,
				["linkpostfix"] = args.qlinkpostfix,
				["wdl"]         = "false",
				["unitabbr"]    = tostring(uabbr),
				["maxvals"]     = 0,
				["sorted"]      = args.qsorted,
				["noicon"]      = "true",
				["list"]        = "",
				["sep"]         = qsep,
				["langobj"]     = args.langobj,
			}
			if qualID == "DATES" then qargs.maxvals = 1 end
			local qlist = {}
			local t1, t2, dsep = "", "", ""
			for k1, v1 in pairs(v.qualifiers) do
				-- look for date range:
				if qualID == "DATES" then
					if k1 == "P580" then -- P580 is "start time"
						t1 = propertyvalueandquals(v1, qargs)[1] or ""
					elseif k1 == "P582" then -- P582 is "end time"
						t2 = propertyvalueandquals(v1, qargs)[1] or ""
					end
				-- check for latest date qualifier:
				elseif k1 == "P1326" then
					-- do nothing - this is handled already
				-- otherwise see if we want this qualifier:
				elseif qualID == "ALL" or qualID == k1 then 
					local ql = propertyvalueandquals(v1, qargs)
					for k2, v2 in ipairs(ql) do
						qlist[#qlist + 1] = v2
					end
				end
			end -- of loop through qualifiers
			local t = t1 .. t2
			-- *** internationalise date separators later ***
			if t:find("%s") or t:find("&nbsp;") then dsep = "  &ndash; " else dsep = "&ndash;" end
			if #qlist > 0 then
				local qstr = assembleoutput(qlist, qargs)
				out[#out] = out[#out] .. " (" .. qstr .. ")"
			elseif t > "" then
				out[#out] = out[#out] .. " (" .. t1 .. dsep .. t2 .. ")"
			end
		end -- of test for qualifiers wanted
		if maxvals > 0 and #out >= maxvals then break end
	end -- of for each value loop

	-- we need to pick one value to return if the datatype was "monolingualtext"
	-- if there's only one value, use that
	-- otherwise look through the fallback languages for a match
	if datatype == "monolingualtext" and #out >1 then
		local langcode = args.langobj.code
		langcode = mw.text.split( langcode, '-', true )[1]
		local fbtbl = mw.language.getFallbacksFor( langcode )
		table.insert( fbtbl, 1, langcode )
		bestval = ""
		found = false
		for idx1, lang1 in ipairs(fbtbl) do
			for idx2, lang2 in ipairs(mtl) do
				if (lang1 == lang2) and not found then
					bestval = out[idx2]
					found = true
					break
				end
			end -- loop through values of property
		end -- loop through fallback languages
		if found then
			-- replace output table with a table containing the best value
			out = { bestval }
		else
			-- more than one value and none of them on the list of fallback languages
			-- sod it, just give them the first one
			out = { out[1] }
		end
	end
	return out
end

-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
-- Public functions
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
-- getValue is used to get the value(s) of a property
-- The property ID is passed as the first unnamed parameter and is required.
-- A locally supplied parameter may optionaly be supplied as the second unnamed parameter.
-- The function will now also return qualifiers if parameter qual is supplied
-------------------------------------------------------------------------------
-- Dependencies: setRanks; parseInput; propertyvalueandquals; assembleoutput; parseParam; sourced; 
-- labelOrId; i18n.latestdatequalifier; format_Date; makeOrdinal; roundto; decimalPrecision; decimalToDMS;
-------------------------------------------------------------------------------
p.getValue = function(frame)
	if not frame.args[1] then
		frame.args = frame:getParent().args
		if not frame.args[1] then return i18n.errors["No property supplied"] end
	end

	local propertyID = mw.text.trim(frame.args[1] or "")

	frame.args.reqranks = setRanks(frame.args.rank)

	local entityid, props = parseInput(frame, frame.args[2], propertyID)

	if not entityid then
		return props -- either the input parameter or nothing
	end
	-- qual is a string containing the property ID of the qualifier(s) to be returned
	-- if qual == "ALL" then all qualifiers returned
	-- if qual == "DATES" then qualifiers P580 (start time) and P582 (end time) returned
	-- if nothing or an empty string is passed set it nil -> no qualifiers returned
	local qualID = mw.text.trim(frame.args.qual or ""):upper()
	if qualID == "" then qualID = nil end

	-- set a language object in the frame.args table
	frame.args.langobj = findLang(frame.args.lang)

	-- table 'out' stores the return value(s):
	local out = propertyvalueandquals(props, frame.args, qualID)

	-- format the table of values and return it as a string:
	return assembleoutput(out, frame.args, entityid, propertyID)
end


-------------------------------------------------------------------------------
-- getPreferredValue is used to get a value,
-- (or a comma separated list of them if multiple values exist).
-- If preferred ranks are set, it will return those values, otherwise values with normal ranks
-- now redundant to getValue with |rank=best
-------------------------------------------------------------------------------
-- Dependencies: p.getValue; setRanks; parseInput; propertyvalueandquals; assembleoutput;
-- parseParam; sourced; labelOrId; i18n.latestdatequalifier; format_Date;
-- makeOrdinal; roundto; decimalPrecision; decimalToDMS;
-------------------------------------------------------------------------------
p.getPreferredValue = function(frame)
	frame.args.rank = "best"
	return p.getValue(frame)
end

-------------------------------------------------------------------------------
-- getCoords is used to get coordinates for display in an infobox
-- whitelist and blacklist are implemented
-- optional 'display' parameter is allowed, defaults to "inline, title"
-------------------------------------------------------------------------------
-- Dependencies: setRanks; parseInput; decimalPrecision;
-------------------------------------------------------------------------------
p.getCoords = function(frame)
	local propertyID = "P625"

	-- if there is a 'display' parameter supplied, use it
	-- otherwise default to "inline, title"
	local disp = frame.args.display or ""
	if disp == "" then
		disp = "inline, title"
	end

	-- there may be a format parameter to switch from deg/min/sec to decimal degrees
	-- default is deg/min/sec
	-- decimal degrees needs |format = dec
	local form = (frame.args.format or ""):lower():sub(1,3)
	if form ~= "dec" then
		form = "dms"
	end

	-- just deal with best values
	frame.args.reqranks = setRanks("best")

	local qid, props = parseInput(frame, frame.args[1], propertyID)
	if not qid then
		return props -- either local parameter or nothing
	else
		dv = props[1].mainsnak.datavalue.value
		local lat, long, prec = dv.latitude, dv.longitude, dv.precision
		lat = decimalPrecision(lat, prec)
		long = decimalPrecision(long, prec)
		local lat_long = { lat, long }
		lat_long["display"] = disp
		lat_long["format"] = form
		-- invoke template Coord with the values stored in the table
		return frame:expandTemplate{title = 'coord', args = lat_long}
	end
end


-------------------------------------------------------------------------------
-- getQualifierValue is used to get a formatted value of a qualifier
--
-- The call needs:	a property (the unnamed parameter or 1=)
-- 					a target value for that property (pval=)
--					a qualifier for that target value (qual=)
-- The usual whitelisting and blacklisting of the property is implemented
-- The boolean onlysourced= parameter can be set to return nothing
-- when the property is unsourced (or only sourced to Wikipedia)
-------------------------------------------------------------------------------
-- Dependencies: parseParam; setRanks; parseInput; sourced; propertyvalueandquals; assembleoutput; labelOrId;
-- i18n.latestdatequalifier; format_Date; findLang; makeOrdinal; roundto; decimalPrecision; decimalToDMS;
-------------------------------------------------------------------------------
p.getQualifierValue = function(frame)

	-- The property ID that will have a qualifier is the first unnamed parameter
	local propertyID = mw.text.trim(frame.args[1] or "")

	-- The value of the property we want to match whose qualifier value is to be returned
	-- is passed in named parameter |pval=
	local propvalue = frame.args.pval

	-- The property ID of the qualifier
	-- whose value is to be returned is passed in named parameter |qual=
	local qualifierID = frame.args.qual

	-- onlysourced is a boolean passed to return qualifiers
	-- only when property values are sourced to something other than Wikipedia
	-- if nothing or an empty string is passed set it true
	-- if "false" or "no" or 0 is passed set it false
	local onlysrc = parseParam(frame.args.onlysourced or frame.args.osd, true)

	-- set a language object in the frame.args table
	frame.args.langobj = findLang(frame.args.lang)

	-- set the requested ranks flags
	frame.args.reqranks = setRanks(frame.args.rank)

	-- check for locally supplied parameter in second unnamed parameter
	-- success means no local parameter and the property exists
	local qid, props = parseInput(frame, frame.args[2], propertyID)
	if qid then
		local out = {}
		-- Scan through the values of the property
		-- we want something like property is P793, significant event (in propertyID)
		-- whose value is something like Q385378, construction (in propvalue)
		-- then we can return the value(s) of a qualifier such as P580, start time (in qualifierID)
		for k1, v1 in pairs(props) do
			if v1.mainsnak.snaktype == "value" and v1.mainsnak.datavalue.type == "wikibase-entityid" then
				-- It's a wiki-linked value, so check if it's the target (in propvalue)
				-- and if it has qualifiers
				if v1.mainsnak.datavalue.value.id == propvalue and v1.qualifiers then
					if onlysrc == false or sourced(v1) then
						-- if we've got this far, we have a (sourced) claim with qualifiers
						-- which matches the target, so find the value(s) of the qualifier we want
						local quals = v1.qualifiers[qualifierID]
						if quals then
							local vals = propertyvalueandquals(quals, frame.args, qid)
							for k, v in pairs(vals) do
								out[#out + 1] = v
							end
						end
					end -- of check for sourced
				end -- of check for matching required value and has qualifiers
			end -- of check for wikibase entity
		end -- of loop through values of propertyID
		return assembleoutput(out, frame.args, qid, propertyID)
	else
		return props -- either local parameter or nothing
	end -- of test for success
	return nil
end
-------------------------------------------------------------------------------
-- getValueByQual gets the value of a property which has a qualifier with a given entity value
-- The call needs:
--					a property ID (the unnamed parameter or 1=Pxxx)
--					the ID of a qualifier for that property (qualID=Pyyy)
--					the Wikibase-entity ID of a value for that qualifier (qvalue=Qzzz)
-- The usual whitelisting, blacklisting, onlysourced, etc. are implemented
-------------------------------------------------------------------------------
-- Dependencies: _getvaluebyqual; parseParam; setRanks; parseInput; sourced;
-- assembleoutput;
-------------------------------------------------------------------------------
p.getValueByQual = function(frame)
	local qualID = frame.args.qualID
	-- The Q-id of the value for the qualifier we want to match is in named parameter |qvalue=
	local qval = frame.args.qvalue or ""
	if qval == "" then return "no qualifier value supplied" end
	local function checkQID(id)
		return id == qval
	end
	return _getvaluebyqual(frame, qualID, checkQID)
end
-------------------------------------------------------------------------------
-- getValueByLang gets the value of a property which has a qualifier P407
-- ("language of work or name") whose value has the given language code
-- The call needs:
--					a property ID (the unnamed parameter or 1=Pxxx)
--					the MediaWiki language code to match the language (lang=xx[-yy])
--					(if no code is supplied, it uses the default language)
-- The usual whitelisting, blacklisting, onlysourced, etc. are implemented
-------------------------------------------------------------------------------
-- Dependencies: _getvaluebyqual; parseParam; setRanks; parseInput; sourced; assembleoutput;
-------------------------------------------------------------------------------
p.getValueByLang = function(frame)
	
	-- The language code for the qualifier we want to match is in named parameter |lang=
	local langcode = frame.args.lang or ""
	if langcode == "" then
		langcode = frame:callParserFunction{ name = "int", args = "lang" }
	end
	function checkLanguage(id)
		-- id should represent a language like "British English (Q7979)"
		-- it should have string property "Wikimedia language code (P424)"
		-- qlcode will be a table:
		local qlcode = mw.wikibase.getBestStatements(id, "P424")
		if (#qlcode > 0) and (qlcode[1].mainsnak.datavalue.value == langcode) then
			return true
		end
	end
	return _getvaluebyqual(frame, "P407", checkLanguage)
end
-------------------------------------------------------------------------------
-- Common code for p.getValueByQual and p.getValueByLang
-------------------------------------------------------------------------------
-- Dependencies: parseParam; setRanks; parseInput; sourced; assembleoutput;
-------------------------------------------------------------------------------
function _getvaluebyqual(frame, qualID, checkvalue)

	-- The property ID that will have a qualifier is the first unnamed parameter
	local propertyID = mw.text.trim(frame.args[1] or "")
	if propertyID == "" then return "no property supplied" end
	
	if qualID == "" then return "no qualifier supplied" end

	-- onlysourced is a boolean passed to return property values
	-- only when property values are sourced to something other than Wikipedia
	-- if nothing or an empty string is passed set it true
	-- if "false" or "no" or 0 is passed set it false
	local onlysrc = parseParam(frame.args.onlysourced or frame.args.osd, true)

	-- set the requested ranks flags
	frame.args.reqranks = setRanks(frame.args.rank)

	-- check for locally supplied parameter in second unnamed parameter
	-- success means no local parameter and the property exists
	local qid, props = parseInput(frame, frame.args[2], propertyID)

	if qid then
		local out = {}
		-- Scan through the values of the property
		-- we want something like property is "pronunciation audio (P443)" in propertyID
		-- with a qualifier like "language of work or name (P407)" in qualID
		-- whose value has the required ID, like "British English (Q7979)", in qval
		for k1, v1 in pairs(props) do
			if v1.mainsnak.snaktype == "value" and v1.mainsnak.datavalue.type == "string" then
				-- We'll only deal with returning strings for now
				-- so check if it has the right qualifier
				local v1q = v1.qualifiers
				if v1q and v1q[qualID] then
					if onlysrc == false or sourced(v1) then
						-- if we've got this far, we have a (sourced) claim with qualifiers
						-- so see if matches the required value
						-- We'll only deal with wikibase-items for now
						if v1q[qualID][1].datatype == "wikibase-item" then
							if checkvalue(v1q[qualID][1].datavalue.value.id) then
								out[#out + 1] = v1.mainsnak.datavalue.value
							end
						end
					end -- of check for sourced
				end -- of check for matching required value and has qualifiers
			else
				return "not string"
			end -- of check for string
		end -- of loop through values of propertyID
		return assembleoutput(out, frame.args, qid, propertyID)
	else
		return props -- either local parameter or nothing
	end -- of test for success
	return nil
end

-------------------------------------------------------------------------------
-- getLink has the qid of a Wikidata entity passed as the first unnamed parameter or as |qid=
-- If there is a sitelink to an article on the local Wiki, it returns a link to the article
-- with the Wikidata label as the displayed text.
-- If there is no sitelink, it returns the label as plain text.
-- If there is no label in the local language, it displays the qid instead.
-------------------------------------------------------------------------------
p.getLink = function(frame)
	local itemID = mw.text.trim(frame.args[1] or frame.args.qid or "")
	if itemID == "" then return end
	local sitelink = mw.wikibase.sitelink(itemID)
	local label = labelOrId(itemID)
	if sitelink then
		return "[[" .. sitelink .. "|" .. label .. "]]"
	else
		return label
	end
end


-------------------------------------------------------------------------------
-- getLabel has the qid of a Wikidata entity passed as the first unnamed parameter or as |qid=
-- It returns the Wikidata label for the local language as plain text.
-- If there is no label in the local language, it displays the qid instead.
-------------------------------------------------------------------------------
p.getLabel = function(frame)
	local itemID = mw.text.trim(frame.args[1] or frame.args.qid or "")
	if itemID == "" then return end
	local label = labelOrId(itemID)
	return label
end


-------------------------------------------------------------------------------
-- getAT has the qid of a Wikidata entity passed as the first unnamed parameter or as |qid=
-- If there is a sitelink to an article on the local Wiki, it returns the sitelink as plain text.
-- If there is no sitelink, it returns nothing.
-------------------------------------------------------------------------------
p.getAT = function(frame)
	local itemID = mw.text.trim(frame.args[1] or frame.args.qid or "")
	if itemID == "" then return end
	return mw.wikibase.sitelink(itemID)
end


-------------------------------------------------------------------------------
-- getDescription has the qid of a Wikidata entity passed as |qid=
-- (it defaults to the associated qid of the current article if omitted)
-- and a local parameter passed as the first unnamed parameter.
-- Any local parameter passed (other than "Wikidata" or "none") becomes the return value.
-- It returns the article description for the Wikidata entity if the local parameter is "Wikidata".
-- Nothing is returned if the description doesn't exist or "none" is passed as the local parameter.
-------------------------------------------------------------------------------
p.getDescription = function(frame)
	local desc = mw.text.trim(frame.args[1] or "")
	local itemID = mw.text.trim(frame.args.qid or "")
	if itemID == "" then itemID = nil end
	if desc:lower() == 'wikidata' then
		return mw.wikibase.description(itemID)
	elseif desc:lower() == 'none' then
		return nil
	else
		return desc
	end
end


-------------------------------------------------------------------------------
-- pageId returns the page id (entity ID, Qnnn) of the current page
-- returns nothing if the page is not connected to Wikidata
-------------------------------------------------------------------------------
function p.pageId(frame)
	return mw.wikibase.getEntityIdForCurrentPage()
end


-------------------------------------------------------------------------------
-- formatDate is a wrapper to export the private function format_Date
-------------------------------------------------------------------------------
-- Dependencies: format_Date
-------------------------------------------------------------------------------
p.formatDate = function(frame)
	return format_Date(frame.args[1], frame.args.df, frame.args.bc)
end


-------------------------------------------------------------------------------
-- checkBlacklist allows a test to check whether a named field is allowed
-- returns true if the field is not blacklisted (i.e. allowed)
-- returns false if the field is blacklisted (i.e. disallowed)
-- {{#if:{{#invoke:WikidataIB |checkBlacklist |name=Joe |suppressfields=Dave; Joe; Fred}} | not blacklisted | blacklisted}}
-- displays "blacklisted"
-- {{#if:{{#invoke:WikidataIB |checkBlacklist |name=Jim |suppressfields=Dave; Joe; Fred}} | not blacklisted | blacklisted}}
-- displays "not blacklisted"
-------------------------------------------------------------------------------
p.checkBlacklist = function(frame)
	local blacklist = frame.args.suppressfields or frame.args.spf or ""
	local fieldname = frame.args.name or ""
	if blacklist ~= "" and fieldname ~= "" then
		if blacklist:find(fieldname) then
			return false
		else
			return true
		end
	else
		-- one of the fields is missing: let's call that "not on the list"
		return true
	end
end


-------------------------------------------------------------------------------
-- emptyor returns nil if its first unnamed argument is just punctuation, whitespace or html tags
-- otherwise it returns the argument unchanged (including leading/trailing space).
-- If the argument may contain "=", then it must be called explicitly:
-- |1=arg
-- (In that case, leading and trailing spaces are trimmed)
-- It finds use in infoboxes where it can replace tests like:
-- {{#if: {{#invoke:WikidatIB |getvalue |P99 |fwd=ALL}} | <span class="xxx">{{#invoke:WikidatIB |getvalue |P99 |fwd=ALL}}</span> | }}
-- with a form that uses just a single call to Wikidata:
-- {{#invoke |WikidataIB |emptyor |1= <span class="xxx">{{#invoke:WikidataIB |getvalue |P99 |fwd=ALL}}</span> }}
-------------------------------------------------------------------------------
p.emptyor = function(frame)
	local s = frame.args[1] or ""
	if s == "" then return nil end
	local sx = s:gsub("%s", ""):gsub("<[^>]*>", ""):gsub("%p", "")
	if sx == "" then
		return nil
	else
		return s
	end
end


-------------------------------------------------------------------------------
-- labelorid is a public function to expose the output of labelOrId()
-- Pass the Q-number as |qid= or as an unnamed parameter.
-- It returns the Wikidata label for that entity or the qid if no label exists.
-------------------------------------------------------------------------------
-- Dependencies: labelOrId
-------------------------------------------------------------------------------
p.labelorid = function(frame)
	local label = labelOrId( frame.args.qid or frame.args[1] )
	return label
end


-------------------------------------------------------------------------------
-- getLang returns the MediaWiki language code of the current content.
-- If optional parameter |style=full, it returns the language name.
p.getLang = function(frame)
	local style = (frame.args.style or ""):lower()
	local langcode = mw.language.getContentLanguage().code
	if style == "full" then
		return mw.language.fetchLanguageName( langcode )
	end
	return langcode
end


-------------------------------------------------------------------------------
-- getQid returns the qid, if supplied
-- failing that, the Wikidata entity ID of the "category's main topic (P301)", if it exists
-- failing that, the Wikidata entity ID asociated with the curent page, if it exists
-- otherwise, nothing
p.getQid = function(frame)
	local qid = (frame.args.qid or ""):upper()
	-- check if a qid was passed; if so, return it:
	if qid ~= "" then return qid end
	-- check if there's a "category's main topic (P301)":
	local qid = mw.wikibase.getEntityIdForCurrentPage()
	if qid then
		local prop301 = mw.wikibase.getBestStatements(qid, "P301")
		if prop301[1] then
			local mctid = prop301[1].mainsnak.datavalue.value.id
			if mctid then return mctid end
		end
	end
	-- otherwise return the page qid (if any)
	return qid
end


-------------------------------------------------------------------------------
-- formatNumber formats a number according to the the supplied language code ("|lang=")
-- or the default language if not supplied.
-- The number is the first unnamed parameter or "|num="
-------------------------------------------------------------------------------
-- Dependencies: findLang
-------------------------------------------------------------------------------
p.formatNumber = function(frame)
	local lang
	local num = tonumber(frame.args[1] or frame.args.num) or 0
	lang = findLang(frame.args.lang)
	return lang:formatNum( num )
end

-------------------------------------------------------------------------------
-- examine dumps the property (the unnamed parameter) from the item given by the parameter 'qid'
-- or from the item corresponding to the current page if qid is not supplied.
-------------------------------------------------------------------------------
p.examine = function( frame )
	pid = mw.text.trim( frame.args[1] or frame.args.pid or "" )
	if pid == "" then return "No property supplied" end
	qid = frame.args.qid or ""
	if qid == "" then qid = mw.wikibase.getEntityIdForCurrentPage end
	if not qid then return "No item for this page" end
	return mw.dumpObject( mw.wikibase.getAllStatements( qid, pid ) )
end

return p