Module:Catalog lookup link

--[[	Whitespace is trimmed off both ends and the strings are urlencoded as if they were query strings.	If not specified, |article-link= is used for display as well. If both parameters are not specified, the prefix is omitted completely.	This gets added in front of the last list item instead of the default whitespace which is added without this parameter.	This may be necessary if |list-separator= is used not only to define the list separator but also parts of the item prefix	(except for the first one). (At present, this is used only to cope with format oddities of the template.)
 * 1=, |2=, |3=, |4=, |5=, |6=, |7=, |8=, |9=: Optional unnamed parameters for 0 to 9 items to be listed.
 * article-link=: Optional Wikipedia article name to link to.
 * article-name=: Optional alternative text to be displayed for |article-link= link in front of catalog link.
 * article-postfix=: Optional symbol to be displayed after article name or link (f.e. ":"; omitted, if not defined).
 * link-prefix=: Optional prefix portion of url to external catalog item(s).
 * link-postfix=: Optional postfix portion of url to external catalog item(s).
 * item-prefix=: Optional text displayed in front of each external link (omitted, if not defined)
 * item-postfix=: Optional text displayed immediately after each external link (omitted, if not defined)
 * list-separator=: Optional alternative separator displayed between list items (default: ", ", if not specified). Whitespace must be encoded.
 * list-leadout=: Optional alternative leadout text displayed between the last two list items (f.e. "and", "or", "as well as", etc., default is the |list-separator= or ", ".)
 * leadout-postfix=: Optional alternative postfix text of the leadout (see |list-leadout=) displayed between the last two list items.

new parameters that support access icons: the icons specified in the following parameters are checked agains the list in |allowed-icons=; not in the list? not displayed
 * allowed_icons= – comma-separated list of keywords: free, limited, registration, subscription, none, all (default; same as parameter empty or omitted)
 * url-access-all= – applies specified icon to all items in the list; accepted keywords: free, limited, registration, subscription;
 * url-accessn= – applies specified icon to item n of the list (the nth positional parameter); accepted keywords: free, limited, registration, subscription;

]]

require('Module:No globals'); local getArgs = require ('Module:Arguments').getArgs; local lock_icons = { ['free'] = '', ['registration'] = '', ['limited'] = '', ['subscription'] = '', }

--[[--< I S _ S E T >--

Returns true if argument is set; false otherwise. Argument is 'set' when it exists (not nil) or when it is not an empty string.

]]

local function is_set( var ) return not (var == nil or var == ''); end

--[=[-< M A K E _ L A B E L >--

Makes a wikilinked or plain text label from arguments; when both link and display text is provided, makes a wikilink in the form L|D; if only link is provided, makes a wikilinked label in the form L; if only display is provided, makes a plain-text label; if neither are provided makes a label from postfix, returns an empty string else.

]=]

local function make_label (link, display, postfix) local label = ''; if is_set (link) then if is_set (display) then label = table.concat ({, display, });			-- make L|D wikilinked label else label = table.concat ({, link, });							-- make L wikilinked label end elseif is_set (display) then label = display;														-- plain-text label end

if is_set (label) then return table.concat ({label, postfix, ' '});						-- assemble the complete label else return postfix;															-- no space after postfix if no label end end

--[[--< I C O N _ I N D E X _ G E T >--

returns index into lock_icons[] if value assigned to |url-access= or |url-access-all= is a valid icon selector (free, limited, registration, subscription)

icon selection may be limited to a subset of the icons with: |allow_icons=  may be any of the keywords: free, limited, registration, subscription, none, all

keyword 'all' is default condition; same when |allowed=icons= is empty of omitted

keyword 'none' for use with identifiers where icons are inappropriate (isbn, issn, oclc)

Templates using this module should set: |allow_icons=free for most identifiers; |allow_icons=none for isbn, issn, oclc, etc


 * url-access= is alias of |url-access1=

]]

local function icon_index_get (args, k)	local icon; local param_name = (1 == k and is_set (args['url-access']) and 'url-access') or table.concat ({'url-access', k});	-- make an enumerated parameter name

if is_set (args['url-access-all']) and lock_icons[args['url-access-all']] then	-- if set and valid icon = args['url-access-all'];											-- tentatively

elseif is_set (args[param_name]) and lock_icons[args[param_name]] then		-- if set and valid icon = args[param_name];												-- tentatively

else return nil;																-- neither |url-access-all= nor |url-accessn= set so return nil end

if args['allow_icons'] and args['allow_icons']:find ('none') then			-- if 'none' keyword is present return nil;																-- icons display not allowed end

if not is_set (args['allow_icons']) or args['allow_icons']:find ('all') or args['allow_icons']:find (icon) then	--if all allowed or specified icon is allowed return icon;															-- return selected icon as index into icon table end end

--[[--< M A I N >--

Template entrypoint to this module; arguments come primarily from the parent frame though in templates that use this module, |allowed-icons= is typically set, if needed, in the.

]]

local function main (frame) local args = getArgs (frame); local out_text = '';

if is_set(args[1]) then local result = {}; local label; local article_postfix = args['article-postfix'] or ''; local link_prefix = args['link-prefix'] or ''; local link_postfix = args['link-postfix'] or ''; local item_prefix = args['item-prefix'] or ''; local item_postfix = args['item-postfix'] or ''; local list_separator = args['list-separator'] or ', '; local leadout_postfix = args['leadout-postfix'] or ' '; local list_leadout;

local icon_index; if is_set (args['list-leadout']) then list_leadout = table.concat ({				mw.ustring.gsub (args['list-leadout'], '^(%a)', ' %1'),			-- insert leading space if first character is a letter				leadout_postfix,			}); else list_leadout = ''; end label = make_label (args['article-link'], args['article-name'], article_postfix);

for k, item in ipairs (args) do											-- for each of the positional parameters item = mw.text.trim (item);											-- remove extraneous whitespace if is_set (link_prefix) then										-- if there is link prefix... item = table.concat ({											-- create an external link item					'[',														-- open ext link markup					link_prefix,												-- url prefix					mw.uri.encode (item),										-- item is part of url					link_postfix,												-- url postfix					' ',														-- required space between url and label					item_prefix,												-- label prefix					item,														-- item as label					item_postfix,												-- item postfix					']'															-- close ext link markup				});

icon_index = icon_index_get (args, k);							-- set if icon specified and allowed for this item; nil else if icon_index then item = table.concat ({										-- add access icon markup to this item						' ',							-- this link is plain						item,						' ',					-- and replaced with						lock_icons[icon_index],									-- the appropriate icon						' ',												-- and close the spans						' '					}); end else item = table.concat ({											-- create an unlinked item					item_prefix,												-- label prefix					item,														-- item as label					item_postfix,												-- item postfix				}); end table.insert (result, item);										-- add the item to the result list end if is_set (args['list-leadout']) then out_text = table.concat ({label, mw.text.listToText (result, list_separator, list_leadout)}); else out_text = table.concat ({label, table.concat (result, list_separator)}); end

end	--is_set (args[1]) return out_text end

return {main = main};