---------------- Defining variables--------------------

local Pop_P = "P1082"	-- population property

local Applies_P = "P518"	-- applies to part property

local Pointin_P = "P585" -- point in time property

local DetMeth_P = "P459"	-- determination method property

local RefURL_P = "P854"		-- reference URL

local RefTitle_P = "P1476"	-- reference title

local RefPubIn_P = "P1433"	--reference published in property

local DatePub_P = "P577"	-- date of publication property

local Publisher_P = "P123"	-- publisher property

local Retrieved_P = "P813"	-- retrieved property

local CensusAU_I = "Q5058971"	-- Australian census item

local Instof_P = "P31"			-- instance of property

local ShortN_P = "P1813"		-- short name property



local SAL_I = "Q33112019"	-- state suburb item (includes SSC and SAL)

--local GCCSA_I = "Q112762887"			-- Greater Capital City Statistical Area item

local LGA_I = "Q33127844"			-- Local Government Area item

local UCL_I = "Q33127891"		-- Urban Centre or Locality

--local SA2_I = "Q33128776"		-- SA2

local ILOC_I = "Q112729549"		-- Indigenous Location





local item = nil



--------------- Function GetRefsForClaim to check, collate and format all the reference components----------------------



local function GetRefsForClaim(claim, defaulttitle)

	local refs = ""

	for b,x in pairs(claim.references) do																	-- Loop through all references in a claim and pull out the components

		local refurl = ""																					-- initialise an empty URL, check if there is one then populate with the actual value (if not it stays as an empty string)

		if claim.referencesb].snaksRefURL_P ~= nil then

			refurl = claim.referencesb].snaksRefURL_P][1].datavalue.value

		end



		local reftitle = defaulttitle																		-- Initialise the default title as the Wikidata item title. This is the fallback title if one isn't provided in the references

		if claim.referencesb].snaksRefTitle_P ~= nil then

			reftitle = claim.referencesb].snaksRefTitle_P][1].datavalue.value.text

		end



		local detmet = mw.wikibase.getEntity(claim.qualifiersDetMeth_P][1].datavalue.value.id)					-- Get the dertermination method item



		local pubinlabel = ""																					--Initalising an empty published in label. This is the last option for this value.

		if claim.referencesb].snaksRefPubIn_P ~= nil then													--Checking if the published in part of reference exists (it should for all references)

			local pubin = mw.wikibase.getEntity(claim.referencesb].snaksRefPubIn_P][1].datavalue.value.id)	--If it does then grab the published item and the label of that item

			pubinlabel = pubin.labels.en.value

		end



		local refwork = pubinlabel																				-- This value is used for non-census references, or as a fall-back value for census references with missing parts

		local pubdate = ""																						-- This is the fallback option if published date is missing (no date)

		if claim.referencesb].snaksDatePub_P ~= nil then														-- This is the second option for the published date (given with references - this is used for non-census references)

			pubdate = mw.language.getContentLanguage():formatDate('j F Y', claim.referencesb].snaksDatePub_P][1].datavalue.value.time)

		end



		if detmet.claimsInstof_P ~=nil and detmet.claimsInstof_P][1].mainsnak.datavalue.value.id == CensusAU_I then		-- Checking for census references (which will have different refwork and published date sources)

			refwork = detmet.labels.en.value.." "..pubinlabel																-- Concatenating to get work - determination method + published in (this overwrites the refwork value for census references)

			if detmet.claimsDatePub_P ~=nil then

				pubdate = mw.language.getContentLanguage():formatDate('j F Y', detmet.claimsDatePub_P][1].mainsnak.datavalue.value.time) -- Overwrite the published date value if the determination method item has a date published (for census references)

			end

		end



		local refpublisher = ""																								-- The publisher is empty if missing

		if detmet.claimsPublisher_P ~= nil then

			local publisheritem = mw.wikibase.getEntity(detmet.claimsPublisher_P][1].mainsnak.datavalue.value.id)			-- Get the determination method item and the publisher item ID

			refpublisher = publisheritem.labels.en.value																	-- Get the label of the publisher item

		end



		local refaccessdate = ""																							-- The retrieved date fallback is empty

		if claim.referencesb].snaksRetrieved_P ~= nil then

			refaccessdate = mw.language.getContentLanguage():formatDate('j F Y', claim.referencesb].snaksRetrieved_P][1].datavalue.value.time) -- Populate the retrieved date if it's there

		end



		local appliespart = mw.wikibase.getEntity(claim.qualifiersApplies_P][1].datavalue.value.id).labels.en.value					-- The ABS geography type for the particular claim (to use in reference name)

		local pointintime = mw.language.getContentLanguage():formatDate('Y', claim.qualifiersPointin_P][1].datavalue.value.time)		-- Getting the point in time as a YYYY (to use in the reference name)



		local citewebargs = {																								--Putting all the cite_web arguments into a list (for a single reference)

			url = refurl,

			title = reftitle.." ("..appliespart..")" ,

			date = pubdate,

			work = refwork,

			author = "[["..refpublisher.."]]",																				-- Changed the publisher to author for now to match existing population references

			accessdate = refaccessdate

		}



		local wdeditpencil = mw.getCurrentFrame():expandTemplate{title = 'EditAtWikidata', args = {qid = item.id, pid = claim.id, nbsp = 1}}		--Call the Edit At Wikidata template (to add the edit pencil to end of references)



		local reference = mw.getCurrentFrame():expandTemplate{ title = 'cite web', args = citewebargs }						--expand template to feed arguments to cite_web



		refs = refs..mw.getCurrentFrame():extensionTag{ name = 'ref', content = reference..wdeditpencil, { name = refwork.."_"..pointintime.."_"..appliespart.."_"..reftitle } }	--Add the reference from this iteration to the list of references for this particular claim



	end

	return refs																												-- List of references to be given to reflist

end



---------------This is a function for getting the population geography abbreviation and the Wikipedia article link for the population year  ---------------

local function GetAbbrLabelYearLink(returnclaim)

	local appliespartitem = mw.wikibase.getEntity(returnclaim.qualifiersApplies_P][1].datavalue.value.id)											-- This gets the item ID for the current claim Applied to Part value

	local abbrelabel = appliespartitem.labels.en.value																								-- This is the fall back value for the geography label if no abbreviation (short name) value exists in Wikidata item

	if appliespartitem.claimsShortN_P ~= nil then																									-- If a short name value exists then use thi value instead of the full item label.

		abbrelabel = mw.getCurrentFrame():expandTemplate{title = 'Abbr', args = {appliespartitem.claimsShortN_P][1].mainsnak.datavalue.value.text , appliespartitem.labels.en.value }}		-- Output the abbreviated name with tooltip showing the full label

	end



	local year = string.sub(returnclaim.qualifiersPointin_P][1].datavalue.value.time, 2, 5)														-- Get the population point in time as a year string

	local yearreturn = year																															-- If no links to Wikipedia articles describing population determination method exist then just output year



	local detmetitem = mw.wikibase.getEntity(returnclaim.qualifiersDetMeth_P][1].datavalue.value.id)												-- Get the current claim determination method item

	if detmetitem.sitelinks ~=nil and detmetitem.sitelinks.enwiki ~=nil then																		-- Check if the determination method item has an enwiki URL

		yearreturn = "[["..detmetitem.sitelinks.enwiki.title.."|".. year.."]]"																		-- If it does, use this URL as the link with the year value

	elseif detmetitem.claimsInstof_P ~=nil and detmetitem.claimsInstof_P][1].mainsnak.datavalue.value.id == CensusAU_I	then					-- If there isn't a populated enwiki URL for determination method item AND it's a census determination method then...

		yearreturn = "[[Census_in_Australia#"..year.."|".. year.."]]"																				-- ... return the population year linked to the corresponding section of the Census in Australia article

	end

	return abbrelabel.." "..yearreturn																												-- Join the geography abbreviation to the year (with link) ready for the final output

end







---------------- This ListForInfobox function is being used to grab the correct population value ---------------



local p = {}



function p.ListForInfobox( frame )

	local luaplacetype = ""														--Initialise the local place type

	if frame.args.type == nil then

		return ""

	end

	local articleplacetype = string.lower(frame.args.type)						-- Bring in the place type entered into Infobox Australian place template, change to a lower case string

	if articleplacetype == "town" then											-- Check which place type and match to the equivalent ABS geographic area "city", "suburb", "town", "lga", "region"

		luaplacetype = UCL_I

	elseif articleplacetype == "suburb" then

		luaplacetype = SAL_I

	elseif articleplacetype == "city" then

		luaplacetype = UCL_I

	elseif articleplacetype == "lga" then

		luaplacetype = LGA_I

	elseif articleplacetype == "region" then	-- for now saying region == LGA_I... but unclear what is most apprpriate ABS geography type.... can revise

		luaplacetype = LGA_I

	end



	if frame.args.wikidata ~= nil and frame.args.wikidata ~= "" then			-- checking if there's a linked Wikidata item for the article

		item = mw.wikibase.getEntity(frame.args.wikidata)						-- this is the default item specified by the wikidata parameter in the template

	else

		item = mw.wikibase.getEntity()											-- If there's a Wikidata item connected to the article it will find it here.

	end





--	mw.logObject(item)



--------------- CHECK: If item.claims[Pop_P] is nil. If it is return an empty string ----------------------

	if not (item and item.claims and item.claimsPop_P]) then

		return ""

	end





------------ PART 1: Find claims with (1) point in time is not nil, (2) applies to part is not nil, (3) determination method is not nil and (4) References table is not empty-------------



	local validpopclaims = {}													--initialise the blank claim table for storing all population claims that satisfy the four conditions

	local z = 0																	-- initialise the table row count

	for j, s in pairs(item.claimsPop_P]) do

		if	s.qualifiers ~= nil and

			s.qualifiersPointin_P~= nil and

			s.qualifiersApplies_P ~= nil and

			s.qualifiersDetMeth_P ~= nil and

			s.references ~= nil then

			z = z + 1

			validpopclaimsz=s													-- give the claim a new key in the table

		end

	end



--------------- CHECK: If count of validpopclaims is less than one (eg 0) then return a html message. This checks we have something from which to get a population value and basic reference.--------------

	if #validpopclaims <1 then

		return ""

	end



--------------- PART 2: Compare claim 'applies to part' values against template place type-------------------------

	local templategeog = {}												--initialise the blank claim table for if the template type matches to Wikidata claim applies to part

	local othergeog = {}												--initialise the blank claim table for when the template type doesn't match Wikidata claims applies to part

	local c=0

	local d=0

	for i, q in pairs(validpopclaims) do

		if q.qualifiersApplies_P][1].datavalue.value.id == luaplacetype then		--filter for claims where applies to part = Infobox template type

			c=c+1																	-- give the claim a new key in the table

			templategeogc=q														-- claims with Infobox template type geography

		else

			d=d+1

			othergeogd=q															-- claims with geography other than specified in the Infobox template type.

		end

	end



----------PART 3: Get claims with the maximum 'Point in time' values ------------------

----------PART 3A: Find the max date of claims with template geography-----------------



	local maxclaimspertemplategeog = nil												--initialise the blank claim corresponding to the max date

	for k, v in pairs(templategeog) do													--loop through all the claims with geography type = Infobox template type

		local tclaimdate = v.qualifiersPointin_P][1].datavalue.value.time

		if  maxclaimspertemplategeog == nil

			or (maxclaimspertemplategeog ~= nil

				and tclaimdate >= maxclaimspertemplategeog.qualifiersPointin_P][1].datavalue.value.time)

			then

				maxclaimspertemplategeog=v

		end

	end





----------PART 3B: Find the max date of claims with non-Infobox template geography-----------------



	local maxclaimsperothergeog = {}



	for l, m in pairs(othergeog) do														--loop through all the claims with geography type = non Infobox place type

		local oclaimdate = m.qualifiersPointin_P][1].datavalue.value.time

		local claimgeog = m.qualifiersApplies_P][1].datavalue.value.id

		if  maxclaimsperothergeogclaimgeog == nil										-- using the applies to part value as the table key

			or (maxclaimsperothergeogclaimgeog ~= nil

				and oclaimdate >= maxclaimsperothergeogclaimgeog].qualifiersPointin_P][1].datavalue.value.time)  -- checking the max date for a particular geography value

			then

				maxclaimsperothergeogclaimgeog=m										-- overwrites with a geography-max date claim pair whenever the point in time is bigger than the last iteration.

		end

	end







------------------------------Compiling the module output--------------------------------



	local returnlist = {}																							-- Initiate an empty table to store the output claims

	if maxclaimspertemplategeog ~=nil then													-- Situation 1: Getting population for max date claim where applies to part matches the Infobox place type

		local templategeogrefs = GetRefsForClaim(maxclaimspertemplategeog, item.labels.en.value)					-- Getting the references for max date claim where Wikidata applies to part matches the Infobox place type

		table.insert (returnlist, mw.language.getContentLanguage():formatNum(tonumber(maxclaimspertemplategeog.mainsnak.datavalue.value.amount)).." ("..GetAbbrLabelYearLink(maxclaimspertemplategeog)..")"..templategeogrefs)  --Insert the return string to returnlist. With population value, applies to part, point in time, reference



	elseif articleplacetype == "town" then													-- Situation 2: Getting population for max date claims where Infobox place type = town. If no UCL populations (earlier default) then get ILOC and SAL populations.

		if maxclaimsperothergeogILOC_I~=nil then

			local ILOCrefs = GetRefsForClaim(maxclaimsperothergeogILOC_I], item.labels.en.value)					-- Getting the references for max date claim where applies to part = ILOC

			table.insert (returnlist, mw.language.getContentLanguage():formatNum(tonumber(maxclaimsperothergeogILOC_I].mainsnak.datavalue.value.amount)).." ("..GetAbbrLabelYearLink(maxclaimsperothergeogILOC_I])..")"..ILOCrefs) --Insert the return string to returnlist. With population value, applies to part, point in time, reference

		end

		if maxclaimsperothergeogSAL_I~=nil then

			local SALrefs = GetRefsForClaim(maxclaimsperothergeogSAL_I], item.labels.en.value)						-- Getting the references for max date claim where applies to part = SAL

			table.insert (returnlist, mw.language.getContentLanguage():formatNum(tonumber(maxclaimsperothergeogSAL_I].mainsnak.datavalue.value.amount)).." ("..GetAbbrLabelYearLink(maxclaimsperothergeogSAL_I])..")"..SALrefs)		--Insert the return string to returnlist. With population value, applies to part, point in time, reference

		end

	else

		for a, w in pairs(maxclaimsperothergeog) do											-- Situation 3: Getting population for max date claims where applies to part doesn't = Infobox place type, and Infobox place type doesn't = town.

			local othergeogrefs = GetRefsForClaim(w, item.labels.en.value)											-- Loop through the claims in maxclaimsperothergeog and output all of them

			table.insert (returnlist, mw.language.getContentLanguage():formatNum(tonumber(maxclaimsperothergeoga].mainsnak.datavalue.value.amount)).." ("..GetAbbrLabelYearLink(maxclaimsperothergeoga])..")"..othergeogrefs)		--Insert the return string to returnlist. With population value, applies to part, point in time, reference

		end

	end



	local wikitext = ""																								-- Initialise an empty string output (this is the value that goes back to the Infobox Australian place)

	if #returnlist == 1 then																						-- If there is only one formatted "population (geography year)" string (one row) in returnlist then return it without a bullet point

		wikitext = returnlist1

	else

		wikitext = "\n*"..table.concat(returnlist,"\n*")															-- If there are multiple formatted "population (geography year)" strings (multiple rows) in returnlist then return all the rows with new line and bullet points between them

	end

	return  wikitext..'[[Category:Australian place articles using Wikidata population values]]'						-- Append the category to the output so we can keep track of which articles are using this module to output a population value

end



return p