# Module:Delink

-- This module de-links most wikitext.  
require("strict")  
local p = {}  
local getArgs  
local function delinkReversePipeTrick(s)
if s:match("^%[%[|.*[|\n]") then -- Check for newlines or multiple pipes.
return s
end
return s:match("%[%[|(.*)%]%]")  
end  
local function delinkPipeTrick(s)
-- We need to deal with colons, brackets, and commas, per .
-- First, remove the text before the first colon, if any.
if s:match(":") then
s = s:match("%[%[.-:(.*)|%]%]")
-- If there are no colons, grab all of the text apart from the square brackets and the pipe.
else
s = s:match("%[%[(.*)|%]%]")
end  
-- Next up, brackets and commas.
if s:match("%(.-%)$") then -- Brackets trump commas.
s = s:match("(.-) ?%(.-%)$")
elseif s:match(",") then -- If there are no brackets, display only the text before the first comma.
s = s:match("(.-),.*$")
end
return s
end  
-- Return wikilink target |wikilinks=target
local function getDelinkedTarget(s)
local result = s
-- Deal with the reverse pipe trick.
if result:match("%[%[|") then
return delinkReversePipeTrick(result)
end  
result = mw.uri.decode(result, "PATH") -- decode percent-encoded entities. Leave underscores and plus signs.
result = mw.text.decode(result, true) -- decode HTML entities.  
-- Check for bad titles. To do this we need to find the
-- title area of the link, i.e. the part before any pipes.
local target_area
if result:match("|") then -- Find if we're dealing with a piped link.
target_area = result:match("^%[%[(.-)|.*%]%]")
else
target_area = result:match("^%[%[(.-)%]%]")
end  
-- Check for bad characters.
if mw.ustring.match(target_area, "[%[%]<>{}%%%c\n]") and mw.ustring.match(target_area, "[%[%]<>{}%%%c\n]") ~= "?" then
return s
end  
return target_area
end  
local function getDelinkedLabel(s)
local result = s
-- Deal with the reverse pipe trick.
if result:match("%[%[|") then
return delinkReversePipeTrick(result)
end  
result = mw.uri.decode(result, "PATH") -- decode percent-encoded entities. Leave underscores and plus signs.
result = mw.text.decode(result, true) -- decode HTML entities.  
-- Check for bad titles. To do this we need to find the
-- title area of the link, i.e. the part before any pipes.
local target_area
if result:match("|") then -- Find if we're dealing with a piped link.
target_area = result:match("^%[%[(.-)|.*%]%]")
else
target_area = result:match("^%[%[(.-)%]%]")
end  
-- Check for bad characters.
if mw.ustring.match(target_area, "[%[%]<>{}%%%c\n]") and mw.ustring.match(target_area, "[%[%]<>{}%%%c\n]") ~= "?" then
return s
end  
-- Check for categories, interwikis, and files.
local colon_prefix = result:match("%[%[(.-):.*%]%]") or "" -- Get the text before the first colon.
local ns = mw.site.namespaces[colon_prefix] -- see if this is a known namespace
if mw.language.isKnownLanguageTag(colon_prefix) or (ns and (ns.canonicalName == "File" or ns.canonicalName == "Category")) then
return ""
end  
-- Remove the colon if the link is using the .
if result:match("%[%[:") then
result = "[[" .. result:match("%[%[:(.*%]%])")
end  
-- Deal with links using the .
if mw.ustring.match(result, "^%[%[[^|]*|%]%]") then
return delinkPipeTrick(result)
end  
-- Find the display area of the wikilink
if result:match("|") then -- Find if we're dealing with a piped link.
result = result:match("^%[%[.-|(.+)%]%]")
-- Remove new lines from the display of multiline piped links,
-- where the pipe is before the first new line.
result = result:gsub("\n", "")
else
result = result:match("^%[%[(.-)%]%]")
end  
return result
end  
local function delinkURL(s)
-- Assume we have already delinked internal wikilinks, and that
-- we have been passed some text between two square brackets [foo].  
-- If the text contains a line break it is not formatted as a URL, regardless of other content.
if s:match("\n") then
return s
end  
-- Check if the text has a valid URL prefix and at least one valid URL character.
local valid_url_prefixes = {"//", "http://", "https://", "ftp://", "gopher://", "mailto:", "news:", "irc://"}
local url_prefix
for _ ,v in ipairs(valid_url_prefixes) do
if mw.ustring.match(s, '^%[' .. v ..'[^"%s].*%]' ) then
url_prefix = v
break
end
end  
-- Get display text
if not url_prefix then
return s
end
s = s:match("^%[" .. url_prefix .. "(.*)%]") -- Grab all of the text after the URL prefix and before the final square bracket.
s = s:match('^.-(["<> ].*)') or "" -- Grab all of the text after the first URL separator character ("<> ).
s = mw.ustring.match(s, "^%s*(%S.*)$") or "" -- If the separating character was a space, trim it off.  
local s_decoded = mw.text.decode(s, true)
if mw.ustring.match(s_decoded, "%c") then
return s
end  
return s_decoded  
end  
local function delinkLinkClass(text, pattern, delinkFunction)
if type(text) ~= "string" then
error("Attempt to de-link non-string input.", 2)
end
if type(pattern) ~= "string" or mw.ustring.sub(pattern, 1, 1) ~= "^" then
error('Invalid pattern detected. Patterns must begin with "^".', 2)
end
-- Iterate over the text string, and replace any matched text. using the
-- delink function. We need to iterate character by character rather
-- than just use gsub, otherwise nested links aren't detected properly.
local result = ""
while text ~= "" do
-- Replace text using one iteration of gsub.
text = mw.ustring.gsub(text, pattern, delinkFunction, 1)
-- Append the -most character to the result string.
result = result .. mw.ustring.sub(text, 1, 1)
text = mw.ustring.sub(text, 2, -1)
end
return result
end  
function p._delink(args)
local text = args[1] or ""
if args.refs == "yes" then
-- Remove any representing ref tags. In most situations
-- this is not a good idea - only use it if you know what you are doing!
text = mw.ustring.gsub(text, "UNIQ%w*%-ref%-%d*%-QINU", "")
end
if args.comments ~= "no" then
text = text:gsub("<!%-%-.-%-%->", "") -- Remove html comments.
end  
if args.wikilinks ~= "no" and args.wikilinks ~= "target" then
-- De-link wikilinks and return the label portion of the wikilink.
text = delinkLinkClass(text, "^%[%[.-%]%]", getDelinkedLabel)
elseif args.wikilinks == "target" then
-- De-link wikilinks and return the target portions of the wikilink.
text = delinkLinkClass(text, "^%[%[.-%]%]", getDelinkedTarget)
end
if args.urls ~= "no" then
text = delinkLinkClass(text, "^%[.-%]", delinkURL) -- De-link URLs.
end
if args.whitespace ~= "no" then
-- Replace single new lines with a single space, but leave double new lines
-- and new lines only containing spaces or tabs before a second new line.
text = mw.ustring.gsub(text, "([^\n \t][ \t]*)\n([ \t]*[^\n \t])", "%1 %2")
text = text:gsub("[ \t]+", " ") -- Remove extra tabs and spaces.
end
return text
end  
function p.delink
if not getArgs then
getArgs = require('Module:Arguments').getArgs
end
return p._delink(getArgs(, {wrappers = 'Template:Delink'}))
end  
return p