-- allowing the parameter to be true or false by default.
-- It returns a boolean.
---
-- Dependencies:
---
local parseParam = function(param, default)
if type(param) == "boolean" then param = tostring(param) end
if param and param ~= "" then
param = param:lower
if (param == "false") or (param:sub(1,1) == "n") or (param == "0") then
return false
else
return true
end
else
return default
end
end  
---
-- _getSitelink takes the qid of a Wikidata entity passed as |qid=
-- It takes an optional parameter |wiki= to determine which wiki is to be checked for a sitelink
-- If the parameter is blank, then it uses the local wiki.
-- If there is a sitelink to an article available, it returns the plain text link to the article
-- If there is no sitelink, it returns nil.
---
-- Dependencies:
---
local _getSitelink = function(qid, wiki)
qid = (qid or ""):upper
if qid == "" then qid = mw.wikibase.getEntityIdForCurrentPage end
if not qid then return nil end
wiki = wiki or ""
local sitelink
if wiki == "" then
sitelink = mw.wikibase.getSitelink(qid)
else
sitelink = mw.wikibase.getSitelink(qid, wiki)
end
return sitelink
end  
---
-- _getCommonslink takes an optional qid of a Wikidata entity passed as |qid=
-- It returns one of the following in order of preference:
-- the Commons sitelink of the Wikidata entity - but not if onlycat=true and it's not a category;
-- the Commons sitelink of the topic's main category of the Wikidata entity;
-- the Commons category of the Wikidata entity - unless fallback=false.
---
-- Dependencies: _getSitelink; parseParam
---
local _getCommonslink = function(qid, onlycat, fallback)
qid = (qid or ""):upper
if qid == "" then qid = mw.wikibase.getEntityIdForCurrentPage end
if not qid then return nil end
onlycat = parseParam(onlycat, false)
if fallback == "" then fallback = nil end
local sitelink = _getSitelink(qid, "commonswiki")
if onlycat and sitelink and sitelink:sub(1,9) ~= "Category:" then sitelink = nil end
if not sitelink then
-- check for topic's main category
local prop910 = mw.wikibase.getBestStatements(qid, "P910")[1]
if prop910 then
local tmcid = prop910.mainsnak.datavalue and prop910.mainsnak.datavalue.value.id
sitelink = _getSitelink(tmcid, "commonswiki")
end
if not sitelink then
-- check for list's main category
local prop1754 = mw.wikibase.getBestStatements(qid, "P1754")[1]
if prop1754 then
local tmcid = prop1754.mainsnak.datavalue and prop1754.mainsnak.datavalue.value.id
sitelink = _getSitelink(tmcid, "commonswiki")
end
end
end
if not sitelink and fallback then
-- check for Commons category (string value)
local prop373 = mw.wikibase.getBestStatements(qid, "P373")[1]
if prop373 then
sitelink = prop373.mainsnak.datavalue and prop373.mainsnak.datavalue.value
if sitelink then sitelink = "Category:" .. sitelink end
end
end
return sitelink
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
---
-- Dependencies:
---
local labelOrId = function(id, lang)
if lang == "default" then lang = findLang.code end
local label
if lang then
label = mw.wikibase.getLabelByLang(id, lang)
else
label = mw.wikibase.getLabel(id)
end
if label then
return mw.text.nowiki(label), true
else
return id, false
end
end  
---
-- linkedItem takes an entity-id and returns a string, linked if possible.
-- This is the handler for "wikibase-item". Preferences:
-- 1. Display linked disambiguated sitelink if it exists
-- 2. Display linked label if it is a redirect
-- 3. TBA: Display an inter-language link for the label if it exists other than in default language
-- 4. Display unlinked label if it exists
-- 5. Display entity-id for now to indicate a label could be provided
-- dtxt is text to be used instead of label, or nil.
-- shortname is boolean switch to use P1813 (short name) instead of label if true.
-- lang is the current language code.
-- uselbl is boolean switch to force display of the label instead of the sitelink (default: false)
-- linkredir is boolean switch to allow linking to a redirect (default: false)
-- formatvalue is boolean switch to allow formatting as italics or quoted (default: false)
---
-- Dependencies: labelOrId; donotlink[]
---
local linkedItem = function(id, args)
local lprefix = (args.lp or args.lprefix or args.linkprefix or ""):gsub('"', '') -- toughen against nil values passed
local lpostfix = (args.lpostfix or ""):gsub('"', '')
local prefix = (args.prefix or ""):gsub('"', '')
local postfix = (args.postfix or ""):gsub('"', '')
local dtxt = args.dtxt
local shortname = args.shortname
local lang = args.lang or "en" -- fallback to default if missing
local uselbl = args.uselabel or args.uselbl
uselbl = parseParam(uselbl, false)
local linkredir = args.linkredir
linkredir = parseParam(linkredir, false)
local formatvalue = args.formatvalue or args.fv
formatvalue = parseParam(formatvalue, false)
-- see if item might need italics or quotes
local fmt = ""
if next(formats) and formatvalue then
for k, v in ipairs( mw.wikibase.getBestStatements(id, "P31") ) do
if v.mainsnak.datavalue and formats[v.mainsnak.datavalue.value.id] then
fmt = formats[v.mainsnak.datavalue.value.id]
break -- pick the first match
end
end
end
local disp
local sitelink = mw.wikibase.getSitelink(id)
local label, islabel
if dtxt then
label, islabel = dtxt, true
elseif shortname then
-- see if there is a shortname in our language, and set label to it
for k, v in ipairs( mw.wikibase.getBestStatements(id, "P1813") ) do
if v.mainsnak.datavalue.value.language == lang then
label, islabel = v.mainsnak.datavalue.value.text, true
break
end -- test for language match
end -- loop through values of short name
-- if we have no label set, then there was no shortname available
if not islabel then
label, islabel = labelOrId(id)
shortname = false
end
else
label, islabel = labelOrId(id)
end
if mw.site.siteName ~= "Wikimedia Commons" then
if sitelink then
if not (dtxt or shortname) then
-- if sitelink and label are the same except for case, no need to process further
if sitelink:lower ~= label:lower then
-- strip any namespace or dab from the sitelink
local pos = sitelink:find(":") or 0
local slink = sitelink
if pos > 0 then
local pfx = sitelink:sub(1,pos-1)
if mw.site.namespaces[pfx] then -- that prefix is a valid namespace, so remove it
slink = sitelink:sub(pos+1)
end
end
-- remove stuff after commas or inside parentheses - ie. dabs
slink = slink:gsub("%s%(.+%)$", ""):gsub(",.+$", "")
-- if uselbl is false, use sitelink instead of label
if not uselbl then
-- use slink as display, preserving label case - find("^%u") is true for 1st char uppercase
if label:find("^%u") then
label = slink:gsub("^(%l)", string.upper)
else
label = slink:gsub("^(%u)", string.lower)
end
end
end
end
if donotlink[label] then
disp = prefix .. fmt .. label .. fmt .. postfix
else
disp = "" .. prefix .. fmt .. label .. fmt .. postfix .. ""
end
elseif islabel then
-- no sitelink, label exists, so check if a redirect with that title exists, if linkredir is true
-- display plain label by default
disp = prefix .. fmt .. label .. fmt .. postfix
if linkredir then
local artitle = mw.title.new(label, 0) -- only nil if label has invalid chars
if not donotlink[label] and artitle and artitle.redirectTarget then
-- there's a redirect with the same title as the label, so let's link to that
disp = "" .. prefix .. fmt .. label .. fmt .. postfix .. ""
end
end -- test if article title exists as redirect on current Wiki
else
-- no sitelink and no label, so return whatever was returned from labelOrId for now
-- add tracking category
-- for enwiki, just return the tracking category
if mw.wikibase.getGlobalSiteId == "enwiki" then
disp = i18n.missinginfocat
else
disp = prefix .. label .. postfix .. i18n.missinginfocat
end
end
else
local ccat = mw.wikibase.getBestStatements(id, "P373")[1]