Module:Sort title

local match = require("Module:String")._match

local p = {}

--[[

Local function which is used to return a number without commas.

For example: 4,722 will become 4722.

--]]

local function cleanNumberFromCommas(title)

return string.gsub(title, "(%d+)(,+)", "%1")

end

--[[

Local function which is used to check if the word is an article.

Returns true if it is, false if it isn't.

--]]

local function isFirstWordAnArticle(word)

word = string.lower(word)

if (word == "a" or word == "an" or word == "the") then

return true

else

return false

end

end

--[[

Local function which is used to return the title without its disambiguation.

--]]

local function getTitleWithoutDisambiguation(title, disambiguation)

local newTitle = string.gsub(title, "%(".. disambiguation .. "%)", "")

return mw.text.trim(newTitle)

end

--[[

Local function which is used to return a title without its first word.

--]]

local function getTitleWithoutFirstWord(title)

return mw.ustring.gsub(title, "^[^%s]*%s*", "")

end

--[[

Local function which is used to return the first word from a title.

--]]

local function getFirstWord(title)

return match(title, "^[^%s]*", 1, 1, false, "")

end

--[[

Local function which is used to return a sort key for a specific part.

--]]

local function getSortKey(title, firstWord)

local sortKey = title

if (isFirstWordAnArticle(firstWord) and firstWord ~= title) then

title = getTitleWithoutFirstWord(title)

sortKey = title .. ", " .. firstWord

end

return sortKey

end

--[[

Local function which is used to return the disambiguation sort key.

--]]

local function getDisambiguationSortKey(disambiguation)

if (disambiguation == "") then

return ""

end

local firstWord = getFirstWord(disambiguation)

local disambiguationSortKey = getSortKey(disambiguation, firstWord)

return "(" .. disambiguationSortKey .. ")"

end

--[[

Local function which is used to return the disambiguation from a title.

--]]

local function getDisambiguation(title)

local disambiguation = match(title, "%s%((.-)%)", 1, -1, false, "")

if (disambiguation == "") then

return ""

else

return disambiguation

end

end

--[[

The main function.

--]]

local function _main(title)

if (not title) then

title = mw.title.getCurrentTitle().text

end

local firstWord = getFirstWord(title)

local disambiguation = getDisambiguation(title)

local disambiguationSortKey = getDisambiguationSortKey(disambiguation)

title = getTitleWithoutDisambiguation(title, disambiguation)

title = cleanNumberFromCommas(title)

title = getSortKey(title, firstWord)

local sortKey = title .. " " .. disambiguationSortKey

return mw.text.trim(sortKey)

end

--[[

Public function which allows modules to retrieve a sort key.

--]]

function p._getSortKey()

return _main(nil)

end

--[[

Public function which allows templates to retrieve a sort key.

--]]

function p.getSortKey(frame)

return _main(nil)

end

--[[

Public function which allows templates to retrieve the sort key inside a DEFAULTSORT.

--]]

function p.getDefaultSort(frame)

local sortKey = _main(nil)

return frame:preprocess{text = "{{DEFAULTSORT:" .. sortKey .. "}}"}

end

--[[

Public function which is used for testing various names and not the current page name.

--]]

function p.testcases(frame)

local getArgs = require('Module:Arguments').getArgs

local args = getArgs(frame)

return _main(args[1])

end

return p