Module:Wikidata label

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

--[[  
This module is intended to be the engine behind "Template:Label".

Please do not modify this code without applying the changes first at "Module:Wikidata label/sandbox" and testing 
at "Module:Wikidata label/testcases".

Authors and maintainers:
* User:Jarekt - original version 
]]

-- use different sitelink call depending if you already have an entity or not
local function getSitelink(item, entity, lang)
	if entity then -- if we have entity than use it
		return entity:getSitelink(lang .. 'wiki') 
	else -- if no entity than use different function
		return mw.wikibase.sitelink( item, lang .. 'wiki' )
	end
end

local p = {}

--[[
_getLabel

This function returns a label translated to desired language, created based on wikidata

Inputs:
	1: item - wikidata's item's q-code or entity class
	2: lang - desired language of the label
	3: link_type - link style. Possible values: "wikipedia", "Wikidata", "Commons", or "-" (no link)
	4: capitalization - can be "uc" (upper case), "lc" (lower case), "ucfirst" (upper case for the first letter), 
			"lcfirst" (lower case for the first letter)
 
Error Handling:
	Bad q-code will result in displayed error
]]
function p._getLabel(item, lang, link_type, capitalization)
	local entity, s, link, label, language

	-- clean up the input parameters
	if type(item)~='string' then -- "item" is not a q-code
		entity = item            -- "item" must be the entity
		item   = entity.id       -- look-up q-code
	end
	
	-- build language fallback list
	lang = string.lower(lang) or 'en'
	local langList = mw.language.getFallbacksFor(lang)
	table.insert(langList, 1, lang)
	local userLang = mw.getCurrentFrame():callParserFunction( "int", "lang" )
	
	-- get label (visible part of the link)
	if (userLang==lang) and (not entity) then -- call if requesting label in user's language, but skip if we already have entity
		label, language = mw.wikibase.getLabelWithLang( item ) -- prefered way of calling that do es not need to load entire entity
	end
	-- hard way to get label by querying all the languages on the langList
	if not label then -- used if requesting label in language different than user's, or if we already have entity
		entity = entity or mw.wikibase.getEntity(item) -- load entity if we do not have it yet
		for _, language in ipairs(langList) do         -- loop over language fallback list
			label = entity:getLabel(language)            -- look for label in the specific language
			if label then break end                      -- label found and we are done
		end
	end
	if not label then                                -- no labels found, so just show the q-code
		label = item
	end
	
	-- change capitalization of the label
	if capitalization=='ucfirst' then
		label = mw.language.new(lang):ucfirst(label)
	elseif capitalization=='lcfirst' then
		label = mw.language.new(lang):lcfirst(label)
	elseif capitalization=='uc' then
		label = mw.language.new(lang):uc(label)
	elseif capitalization=='lc' then
		label = mw.language.new(lang):lc(label)
	end

	-- create URL part of the link
	link_type = string.lower(link_type or '')
	local dLink = 'd:'..item; -- create fallback wikidata link
	if string.upper(string.sub(item, 1, 1)) == 'P' then
		dLink = 'd:Property:'.. item
	end
	if link_type=='-' then -- allow different link formats
		link = ''            -- no link
	elseif link_type=='wikidata'  then
		link = dLink         -- link to wikidata
	elseif link_type=='commons' then
		link = getSitelink(item, entity, 'commons')  -- look for sitelink to commons
		if not link then -- try linking to P373 category
			entity = entity or mw.wikibase.getEntity(item);
			s = entity:getBestStatements( 'P373' )
			if s[1] and s[1].mainsnak.datavalue.value then 
				 link = ':Category:' .. s[1].mainsnak.datavalue.value
			end
		end
		if not link then -- try linking to P935 gallery
			s = entity:getBestStatements( 'P935' )
			if s[1] then 
				 link = s[1].mainsnak.datavalue.value
			end
		end
	end
	if not link then-- apply default "Wikipedia" link type
		for _, language in ipairs(langList) do 
			local sitelink = getSitelink(item, entity, language)
			if sitelink then 
				link = mw.ustring.format('w:%s:%s', language, sitelink)
				break 
			end
		end
	end
	link = link or dLink  -- no wiki sitelink, so link to wikidata
	
	-- return the results
	--if entity then label = label .. '_'	end -- this line is uncommented if it is needed for debugging
	if link~='' then
		return mw.ustring.format('[[%s|%s]]', link, label) -- return link
	else
		return label -- return just a label
	end
end


--[[
getLabel
 
This function returns a label translated to desired language, created based on wikidata

Usage:
{{#invoke:Wikidata label|getLabel|item=Q...|lang=..|link_style=..|capitalization=..}}

Parameters
	1: wikidata's item's q-code (required)
	2: language (optional; default {{int:lang}} )
	3: link_style: "wikipedia" (default), "Wikidata", "Commons", or "-" (no link)
	4: capitalization - can be "uc", "lc", "ucfirst", "lcfirst"

Error Handling:
	Bad q-code will result in displayed error
]]
function p.getLabel(frame)
	local args = frame.args
	if not (args.lang and mw.language.isSupportedLanguage(args.lang)) then 
		args.lang = frame:callParserFunction( "int", "lang" ) -- get user's chosen language 
	end
	if (not args.link) or (mw.text.trim(args.link) == "") then
		args.link = "wikipedia"
	end
	if (not args.capitalization) or (mw.text.trim(args.capitalization) == "") then
		args.capitalization = "none"
	end
	args.item = mw.text.trim(args.item or '')
	return p._getLabel(args.item, args.lang, args.link, args.capitalization)
end

--[[
_sitelinks

This function returns a table of sitelinks for a single project organized by language

Inputs:
	1: item - wikidata's item's q-code or entity class
	2: project - "wikipedia", "wikisource", "wikiquote", "wikibooks", "wikinews", "wikiversity", 
			"wikivoyage", "wiktionary", "commons", "mediawiki", "wikispecies", "wikidata",  etc.

Output:
	Table with language fields
]]
function p._sitelinks( item, project )
	local entity, sitelink
	-- get entity
	if type(item)=='string' then -- "item" is a q-code
		entity = mw.wikibase.getEntity(item); 
	else
		entity = item            -- "item" is the entity
		item   = entity.id       -- look-up q-code
	end
	
	-- get project code
	local LUT = {wikipedia='wiki', commons='commonswiki', mediawiki='mediawikiwiki', wikispecies='specieswiki', wikidata='wikidatawiki'}
	project = string.lower(project)
	if LUT[project] then -- correct the project name
		project=LUT[project]
	end
	local n = string.len(project);
	local s ={}
	if entity and entity.sitelinks then 					  -- See if entity exists, and that it has sitelinks
		for _, sitelink in pairs(entity.sitelinks) do 				-- loop over all sitelinks
		  local site = sitelink.site
			local lang = mw.ustring.sub( site, 1, mw.ustring.len(site) - n  )  -- language part of the siteID
			local proj = mw.ustring.sub( site, mw.ustring.len(site) - n + 1 )  -- project part of the siteID
			if proj == project then -- proj matches desired "project"
				s[lang] = sitelink.title
			end
		end
	end
	return s
end

--[[
sitelinks

This function returns a comma separated list of sitelinks for a single project organized by language
Its main purpose is to help with testing of _sitelinks function.

Usage:
{{#invoke:Wikidata label|sitelinks|item=Q...|project=..}}

Inputs:
	1: item - wikidata's item's q-code or entity class
	2: project - "wikipedia" (or "wiki"), "wikisource", "wikiquote", "wikibooks", "wikinews", "wikiversity", "wikivoyage", "wiktionary", etc.

Output:
	comma separated list
]]
function p.sitelinks(frame)
	local sitelinks = p._sitelinks(frame.args.item, frame.args.project)
	local s = {}
	for i, j in pairs(sitelinks) do
		table.insert(s, i .. ':' .. j)
	end
	return table.concat(s, ', ')	
end

--[[
_aliases

This function returns a table of aliases for a single language

Inputs:
	1: item - wikidata's item's q-code or entity class
	2: lang - language code, like 'en' or 'de'

Output:
	Table of aliases
]]
function p._aliases( item, lang )
	local entity
	if type(item)=='string' then -- "item" is a q-code
		entity = mw.wikibase.getEntity(item); 
	else
		entity = item            -- "item" is the entity
		item   = entity.id       -- look-up q-code
	end
	local s = {}
	if entity and entity.aliases then						-- See if there is an entity and that is has aliases
		if entity.aliases[lang] then						-- See if it has English Aliases
			for i, j in pairs(entity.aliases[lang]) do		-- Make a loop around the English aliases
				table.insert(s, j.value)					-- Create a table of English aliases
			end
		end
	end
	return s
end

--[[
aliases

This function returns a comma separated list of aliases for a single language
Its main purpose is to help with testing of _aliases function.

Usage:
{{#invoke:Wikidata label|aliases|item=Q...|lang=..}}

Inputs:
	1: item - wikidata's item's q-code or entity class
	2: lang - language code, like 'en' or 'de'

Output:
	Comma separated list of aliases
]]
function p.aliases(frame)
	return table.concat(p._aliases(frame.args.item, frame.args.lang), ', ')	
end

return p