# Module:WPSHIPS utilities

require('Module:No globals')  

local wpsu={}  

--[[-------------------------< S H I P P R E F I X L I S T >-----------------------------------------------  

This is a list of currently supported ship prefixes.  

To add to this list the form is:  
['prefix'] = true,  
the trailing comma is important.  


local ship_prefix_list =  
{  
['ARA'] = true, -- Armada de la República Argentina  
['ARC'] = true, -- Armada Nacional de la República de Colombia  
['ARM'] = true, -- Armada de la República Mexicana  
['ARV'] = true, -- Armada Republica de Venezuela  
['BAE'] = true, -- Buque de la Armada de Ecuador  
['BAP'] = true, -- Peruvian Navy Ship  
['BNS'] = true, -- Bangladesh Navy Ship  
['BRP'] = true, -- Barko ng Republika ng Pilipinas  
['CCGS'] = true, -- Canadian Coast Guard Ship  
['CFAV'] = true, -- Canadian Forces Auxiliary Vessel  
['CS'] = true, -- Cable Ship  
['CSS'] = true, -- Confederate States Ship  
['FGS'] = true, -- Federal German Ship  
['GTS'] = true, -- Gas Turbine Ship  
['HDMS'] = true, -- His/Her Danish Majesty's Ship  
['HM'] = true, -- His/Her Majesty's, then used with the type of ship in military use (UK)  
['HMAS'] = true, -- Her/His Majesty's Australian Ship  
['HMBS'] = true, -- Her/His Majesty's Britannic Ship (also: Bahamian, Bermudian, Burmese)  
['HMC'] = true, -- Her/His Majesty's Cutter  
['HMCS'] = true, -- Her/His Majesty's Canadian Ship (also Colonial)  
['HMHS'] = true, -- His/Her Majesty's Hospital Ship  
['HMIS'] = true, -- Her/His Majesty's Indian Ship (pre republic)  
['HMNZS'] = true, -- Her/His Majesty's New Zealand Ship  
['HMPNGS'] = true, -- His/Her Majesty's Papua New Guinea Ship  
['HMQS'] = true, -- Her/His Majesty's Queensland Ship  
['HMRC'] = true, -- His/Her Majesty's Revenue Cutter  
['HMS'] = true, -- Her/His Majesty's Ship  
['HMSAS'] = true, -- Her/His Majesty's South African Ship  
['HMT'] = true, -- Her/His Majesty's Trawler  
['HMVS'] = true, -- Her/His Majesty's Victorian Ship  
['HMY'] = true, -- His/Her Majesty's Yacht  
['HNLMS'] = true, -- His/Her Netherlands Majesty’s Ship  
['HNoMS'] = true, -- His/Her Norwegian Majesty's Ship  
['HSwMS'] = true, -- His/Her Swedish Majesty's Ship  
['HTMS'] = true, -- His Thai Majesty's Ship  
['INS'] = true, -- Indian Naval Ship, Israeli Naval Ship  
['JDS'] = true, -- Japanese Defence Ship  
['JS'] = true, -- Japanese Ship (post 2008)  
['KD'] = true, -- Kapal Di-Raja — His Majesty's Ship (Malaysia)  
['KDM'] = true, -- Kongelige Danske Marine  
['KRI'] = true, -- Kapal Republik Indonesia  
['LÉ'] = true, -- Long Éireannach – Irish ship  
['MF'] = true, -- Motor Ferry  
['LKL'] = true, -- Lietuvos Karinis Laivas – Lithuania  
['MS'] = true, -- Motor Ship  
['MT'] = true, -- Motor Tanker  
['MV'] = true, -- Motor Vessel  
['NLV'] = true, -- Northern Lighthouse Vessel  
['NMS'] = true, -- Nava Majestăţii Sale (His/Her Majesty's Ship) - used before 1945 by the Royal Romanian Navy  
['NoCGV'] = true, -- Norwegian Coast Guard Vessel  
['NOAAS'] = true, -- National Oceanic and Atmospheric Administration Ship  
['NRP'] = true, -- Navio da República Portuguesa  
['ORP'] = true, -- Okręt Rzeczypospolitej Polskiej  
['PNS'] = true, -- Pakistani Naval Ship  
['PS'] = true, -- Paddle Steamer  
['RFA'] = true, -- Royal Fleet Auxiliary  
['RMAS'] = true, -- Royal Maritime Auxiliary Service  
['RMS'] = true, -- Royal Mail Ship  
['RNLB'] = true, -- Royal National Lifeboat  
['ROCS'] = true, -- Republic of China Ship  
['ROKS'] = true, -- Republic of Korea Ship  
['RPS'] = true, -- Republic of the Philippines Ship  
['RRS'] = true, -- Royal Research Ship  
['RSS'] = true, -- Republic of Singapore Ship  
['RV'] = true, -- Research Vessel  
['SAS'] = true, -- South African Ship  
['SLNS'] = true, -- Sri Lanka Naval Ship  
['SM'] = true, -- Seiner Majestät Unterseeboot  
['SMS'] = true, -- Seiner Majestät Schiff  
['SS'] = true, -- Screw Steamer or Steamship  
['TCG'] = true, -- Türkiye Cumhuriyeti Gemisi  
['TS'] = true, -- Training ship  
['TV'] = true, -- Training vessel  
['UAM'] = true, -- Unidade Auxiliar da Marinha - Navy Auxiliary Unit (Portuguese Navy non-military ships)  
['USAFS'] = true, -- United States Air Force ship  
['USAHS'] = true, -- United States Army Hospital Ship  
['USAS'] = true, -- United States Army Ship  
['USAT'] = true, -- United States Army Transport  
['USAV'] = true, -- United States Army Vessel  
['USC&GS'] = true, -- United States Coast and Geodetic Survey  
['USC&amp;GS'] = true, -- United States Coast and Geodetic Survey (crude work-around)  
['USC&#38;GS'] = true, -- United States Coast and Geodetic Survey (crude work-around)  
['USC&GSS'] = true, -- United States Coast and Geodetic Survey Ship  
['USC&amp;GSS'] = true, -- United States Coast and Geodetic Survey Ship (crude work-around)  
['USC&#38;GSS'] = true, -- United States Coast and Geodetic Survey Ship (crude work-around)  
['USCGC'] = true, -- United States Coast Guard Cutter  
['USLHT'] = true, -- United State Light House Tender  
['USNS'] = true, -- United States Naval Ship  
['USRC'] = true, -- United States Revenue Cutter  
['USS'] = true, -- United States Ship  
}  

--[[--------------------------< N A T I O N A L I T Y >--------------------------------------------------------  

Article titles for ships in navies that do not use a standardized prefix follow the title format:  
<nationality> <ship type> <name> <(disambiguator)>  

This is a list of nationalities.  

To add to this list the form is:  
['Nationality'] = true,  
the trailing comma is important. Use the adjective form for nationality, always capitalize. Please insert nationalities in alphabetical order.  


local nationality_list =  
{  
['Albanian'] = true,  
['American'] = true,  
['Australian'] = true,  
['Belgian'] = true,  
['Brazilian'] = true,  
['Bulgarian'] = true,  
['Chilean'] = true,  
['Chinese'] = true,  
['Croatian'] = true,  
['Danish'] = true,  
['Dominican'] = true,  
['Dutch'] = true,  
['East Timorese'] = true,  
['Egyptian'] = true,  
['English'] = true,  
['Finnish'] = true,  
['French'] = true,  
['German'] = true,  
['Greek'] = true,  
['Grenadan'] = true,  
['Iranian'] = true,  
['Irish'] = true,  
['Italian'] = true,  
['Japanese'] = true,  
['Latvian'] = true,  
['Libyan'] = true,  
['Lithuanian'] = true,  
['Maltese'] = true,  
['Mexican'] = true,  
['Nigerian'] = true,  
['Ottoman'] = true,  
['Peruvian'] = true,  
['Portuguese'] = true,  
['Romanian'] = true,  
['Russian'] = true,  
['Scottish'] = true,  
['Slovenian'] = true,  
['Soviet'] = true,  
['Spanish'] = true,  
['Swedish'] = true,  
['Texan'] = true,  
['Ukrainian'] = true,  
['United States'] = true,  
['Vietnamese'] = true,  
['Yugoslav'] = true,  
}  

--[[--------------------------< S H I P T Y P E >------------------------------------------------------------  

Article titles for ships in navies that do not use a standardized prefix follow the title format:  
<nationality> <ship type> <name> <(disambiguator)>  

Article titles for ships may or may not be naval ships may follow the title format:  
<name> <(disambiguator)>  
where <(disambiguator)> may be some form of ship type, hull designator or pennant number, or year. This tool will  
format ship names that contain a recognized ship type in <(disambiguator)>.  

This list is used to <find ship> when the article title begins with a nationality. This is important because the tool  
needs to know where the <ship type> ends and <name> begins so that it can properly place the italic markup. The search  
will find an exact match (including case) for ship types that are 1 to 4 words long.  

This list is also used to find ship type in <(disambiguator)>. The search is whole word; use the simplest form.  
For example, because 'icebreaker' is defined, that ship type is sufficient to cause the tool to properly format:  
Astrolabe (icebreaker)  
Krassin (1917 icebreaker)  
Taymyr (nuclear icebreaker)  

Searches for ship type in <(disambiguator)> are whole word. When looking for 'ship', the tool will find  
Auguste (ship)  
Queen of Nations (clipper ship)  
but will not find:  
Sibir (steamship icebreaker) – the search for 'icebreaker' will  

This is a list of ship types. When adding new ship types, do not be too specific: 'aircraft carrier' but not 'light aircraft carrier'  

To add to this list the form is:  
['ship type'] = true,  
the trailing comma is important. At the time of this writing, a ship type may be one to four words, almost always lowercase.  
Please insert ship types in alphabetical order.  


local ship_type_list =  
{  
['armoured cruiser'] = true,  
['aircraft carrier'] = true,  
['amphibious assault ship'] = true,  
['Army ship'] = true, -- should be capitalized  
['auxiliary cruiser'] = true,  
['auxiliary raider'] = true,  
['auxiliary'] = true,  
['aviso'] = true,  
['barge'] = true,  
['barque'] = true,  
['barquentine'] = true,  
['battlecruiser'] = true,  
['battleship'] = true,  
['boat'] = true,  
['brig sloop'] = true,  
['brig-sloop'] = true,  
['brig'] = true,  
['brigantine'] = true,  
['carrack'] = true,  
['clipper'] = true,  
['coast defense ship'] = true,  
['coastal defence ship'] = true,  
['coastal defense ship'] = true,  
['communications ship'] = true,  
['corvette'] = true,  
['cruiser'] = true,  
['cutter'] = true,  
['deep submergence rescue vehicle'] = true,  
['destroyer leader'] = true,  
['destroyer'] = true,  
['dragger'] = true,  
['dredge'] = true,  
['East Indiaman'] = true, -- should be capitalized  
['escort ship'] = true,  
['escort'] = true,  
['ferry'] = true,  
['ferryboat'] = true,  
['fireboat'] = true,  
['fleet oiler'] = true,  
['floating battery'] = true,  
['floating crane'] = true,  
['fluyt'] = true,  
['food supply ship'] = true,  
['freighter'] = true,  
['frigate'] = true,  
['galleon'] = true,  
['galley'] = true,  
['gunboat'] = true,  
['helicopter carrier'] = true,  
['hospital ship'] = true,  
['hovercraft'] = true,  
['hydrofoil'] = true,  
['icebreaker'] = true,  
['Indiaman'] = true, -- should be capitalized  
['ironclad'] = true,  
['ketch'] = true,  
['landing ship medium'] = true,  
['lifeboat'] = true,  
['lightship'] = true,  
['log canoe'] = true,  
['lugger'] = true,  
['merchant cruiser'] = true,  
['minehunter'] = true,  
['minelayer'] = true,  
['minelaying cruiser'] = true,  
['minesweeper'] = true,  
['missile boat'] = true,  
['monitor'] = true,  
['munition ship'] = true,  
['naval ship'] = true,  
['night fighter direction vessel'] = true,  
['ocean liner'] = true,  
['oiler'] = true,  
['paddle steamer'] = true,  
['patrol boat'] = true,  
['patrol gunboat'] = true,  
['patrol vessel'] = true,  
['pinnace'] = true,  
['pollution control vessel'] = true,  
['privateer'] = true,  
['protected cruiser'] = true,  
['pusher'] = true,  
['rescue ship'] = true,  
['riverboat'] = true,  
['ROV'] = true,  
['sailboat'] = true,  
['schooner'] = true,  
['seaplane carrier'] = true,  
['seaplane tender'] = true,  
['ship of the line'] = true,  
['ship'] = true,  
['shipwreck'] = true,  
['shore establishment'] = true, -- use stone frigate instead?  
['showboat'] = true,  
['sidewheeler'] = true,  
['skipjack'] = true,  
['sloop-of-war'] = true,  
['sloop'] = true,  
['smack'] = true,  
['snagboat'] = true,  
['speedboat'] = true,  
['steam frigate'] = true,  
['steam warship'] = true,  
['steamboat'] = true,  
['steamer'] = true,  
['steamship'] = true,  
['sternwheeler'] = true,  
['stores lighter'] = true,  
['submarine chaser'] = true,  
['submarine rescue vehicle'] = true,  
['submarine tender'] = true,  
['submarine'] = true,  
['submersible'] = true,  
['supertanker'] = true,  
['support ship'] = true,  
['survey ship'] = true,  
['tanker'] = true,  
['target ship'] = true,  
['tender'] = true,  
['torpedo boat'] = true,  
['torpedo gunboat'] = true,  
['towboat'] = true,  
['training cruiser'] = true,  
['training ship'] = true,  
['transport'] = true,  
['trawler'] = true,  
['trireme'] = true,  
['tug'] = true,  
['tugboat'] = true,  
['vessel'] = true,  
['warship'] = true,  
['weather ship'] = true,  
['whaler'] = true,  
['whaleship'] = true,  
['wherry'] = true,  
['yacht'] = true,  
['yawl'] = true,  
}  

----------------------------< 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  

----------------------------< S I Z E O F _ S H I P _ T Y P E >----------------------------------------------  

Returns the size in words of ship type. Inputs are the fragment table, the number of elements in the fragment table,  
and the number of words that make up nationality.  

The number of fragments (words) in a ship name dictate the possible sizes of ship type. If nationality takes one fragment,  
and ship type takes four fragments, then the minimum number of fragments in a composite ship name is:  
5 = 1 (nationality) + 3 (ship type) + 1 (ship name) (same as 4 fragments (words) after nationality)  

This function starts at the longest possible series of fragments that might be ship type. This order is important becuase  
some ship types might begin with similar fragments: 'ship' and 'ship of the line'. Starting with the least possible  
series of fragments (1) would find 'ship' and make 'of the line' part of the italicized name.  

Returns 0 if there is no recognizable ship type.  

local function sizeof_ship_type (frag, frag_len, nat_len)  
local ship_type;  

if 5 <= (frag_len - nat_len) then -- must have at least five fragments after nationality for four-word ship type  
ship_type = table.concat (frag, ' ', nat_len+1, nat_len+4); -- four-word ship type  
if ship_type_list [ship_type] then  
return 4;  
end  
end  
if 4 <= (frag_len - nat_len) then -- must have at least four fragments after nationality for three-word ship type  
ship_type = table.concat (frag, ' ', nat_len+1, nat_len+3); -- three-word ship type  
if ship_type_list [ship_type] then  
return 3;  
end  
end  
if 3 <= (frag_len - nat_len) then -- must have at least three fragments after nationality for two-word ship type  
ship_type = table.concat (frag, ' ', nat_len+1, nat_len+2); -- two-word ship type  
if ship_type_list [ship_type] then  
return 2;  
end  
end  
if 2 <= (frag_len - nat_len) then -- must have at least two fragments after nationality for one-word ship type  
if ship_type_list [frag[nat_len+1]] then -- one-word ship type  
return 1;  
end  
end  
return 0; -- no recognizable ship type  
end  

----------------------------< S I Z E O F _ N A T I O N A L I T Y >------------------------------------------  

This function the size (in words) of the nationality from the fragments table. Nationality may be one or two  
words that occupy the first one or two positions in the table.  

Returns the number of words that identify the nationality:  
1 for French or German, etc.  
2 for United States;  
0 when table doesn't have a recognizable nationality  

local function sizeof_nationality (frag, frag_len)  
local nat = '';  

if not nationality_list [frag[1]] then -- if not a one-word nationality  
if 2 <= frag_len - 2 then -- must have at least two fragments after nationality for minimal ship type and name  
nat = table.concat (frag, ' ', 1, 2);  
if nationality_list [nat] then -- is it a two-word nationality?  
return 2; -- yes  
else  
return 0; -- no  
end  
end  
return 0; -- not one-word and not enough fragments for two-word  
end  
return 1; -- one-word nationality  
end  

--[[-------------------------< S H I P _ N A M E _ F O R M A T >-----------------------------------------------  

This function applies correct styling to ship and ship-class names. These names are, for example, ship-article titles  
used by templates , , where the article title is to be rendered with proper  
styling.  

This function requires one argument:  
|name= (required): a name is required; if missing or empty, this function returns an error message (may or may not be visible depending on where it is used)  
used in to provide a value for and to provide a value for |infobox caption=  

Optional arguments to support :  
|dab= – displays ship name without parenthetical disambiguator; use when |infobox caption=nodab  
|sclass=2 – for ship classes only; displays class name without italics (parameter name is loosely similar to which does the same thing); use when |infobox caption=class  
|adj=off – for ship classes only; displays class name as a noun (no hyphen, no ship type); use when |infobox caption=class  

Arguments are passed in a table.  

to call this function locally:  
do_ship_name_format ({['name=name'], ['dab']=dab, ['sclass']=sclass, ['adj']=adj, ['showerrs']=showerrs}) or  
args = {['name=name'], ['dab']=dab, ['sclass']=sclass, ['adj']=adj, ['showerrs']=showerrs};  
do_ship_name_format (args)  

The function returns the formatted name or, if unable to format the name, the original name and an unformatted error message.  


local function do_ship_name_format (args)  
local name_sans_dab; -- the ship or class name without a trailing parenthetical dab  
local dab; -- the dab stripped from the name  
local fragments = {}; -- a table of words that make up name_sans_dab  
local ship_type; -- a word or phrase that describes a ship  
local type_len; -- the number of words that describe a ship  
local nat_len; -- the number of words used to specify a ship's nationality  
local name = ''; -- the reassembles and formatted ship name  
local error_msg = ''; -- a repository for error messages if any  

-- args.name = mw.text.decode (args.name); -- replace html entities in title with their characters; doesn't work for &amp; and &#38; in prefix  
args.name = args.name:gsub ("&#39;", "\'"); -- replace html appostrophe with the character  
-- args.name = args.name:gsub ("&amp;", "&");  
-- args.name = args.name:gsub ("&#38;", "&");  
-- args.name = args.name:gsub ("&amp;", "&#38;");  

if args.name:match ('.+%-class%s+%a+') then -- if a ship-class  
fragments = mw.text.split (args.name, '-class' ); -- split at -class  
if '2' == args.sclass then -- for DISPLAYTITLE and infobox caption when class not named for a member of the class  
if 'off' == args.adj then  
return fragments[1] .. ' class'; -- for infobox caption do noun form <name> class (no hyphen, no ship type)  
end  
return args.name; -- nothing to do so return original unformatted name  
end  
if 'off' == args.adj then  
return "*" .. fragments[1] .. "* class"; -- for infobox caption do noun form <name> class (no hyphen, no ship type)  
end  
return "*" .. fragments[1] .. "*-class" .. fragments[2]; -- and return formatted adjectival name  
end  
-- not a ship class so try to format a ship name  
name_sans_dab, dab = args.name:match('^(.+)%s+(%b)%s*$'); -- split name into name_sans_dab and dab  
if is_set (dab) then  
dab = ' ' .. dab; -- insert a space for later reassembly  
else  
name_sans_dab = args.name; -- because without a dab, the string.match returns nil  
dab = ''; -- empty string for concatenation  
end  

fragments = mw.text.split (name_sans_dab, '%s' ); -- split into a table of separate words  

nat_len = sizeof_nationality (fragments, #fragments); -- get the number of words in the ship's nationality  
if 0 < nat_len then -- if not zero we have a valid nationality  
type_len = sizeof_ship_type (fragments, #fragments, nat_len); -- get the number of words in the ship type  
if 0 < type_len then -- if not zero, ship type is valid; nationality and type not italics, the rest is name  
name = "*" .. table.concat (fragments, ' ', nat_len + type_len + 1) .. "*"; -- format name  
if '' == args.dab then -- for |infobox caption=nodab  
return name; -- return the formatted name without the nationality or ship type or dab  
end  
name = table.concat (fragments, ' ', 1, nat_len + type_len) .. " " .. name; -- assemble everything but dab  
else  
error_msg = ' unrecognized ship type;'; -- valid nationality, invalid ship type  
end  
elseif ship_prefix_list[fragments[1]] then -- if the first fragment is a ship prefix  
name = table.remove (fragments, 1); -- fetch it from the table  
name = name .. " *" .. table.concat (fragments, ' ') .. "*"; -- assemble formatted name  
else  
error_msg = ' no nationality or prefix;'; -- invalid nationality and first word in ship name not a valid prefix  
end  

if is_set (name) then -- name will be set if we were able to format it  
if '' == args.dab then -- for |infobox caption=nodab  
return name; -- return the formatted name without the dab  
end  
return name .. dab; -- return the formatted name with the dab  
end  

if is_set (dab) then  
if dab:match ('%(%u+[%- ]?%d+%)') or -- one or more uppercase letters, optional space or hyphen, one or more digits  
dab:match ('%(%d+[%- ]?%u+%)') or -- one or more digits, optional space or hyphen, one or more uppercase letters  
dab:match ('%(%u[%u%-]*%-%d+%)') or -- one or more uppercase letters with hyphens, a hyphen, one or more digits (e.g., T-AO-157)  
dab:match ('%([12]%d%d%d%)') then -- four digits representing year in the range 1000–2999  
name = "*" .. table.concat (fragments, ' ') .. "*"; -- format the name  
if '' == args.dab then -- for |infobox caption=nodab  
return name; -- return the formatted name without the dab  
end  
return name .. dab; -- return the formatted name with the dab  
end  
-- last chance, is there a ship type in the dab?  
for key, _ in pairs (ship_type_list) do -- spin through the ship type list and see if there is a ship type (key) in the dab  
if dab:find ('%f[%a]' .. key .. '%f[^%a]') then -- avoid matches that are not whole word  
name = "*" .. table.concat (fragments, ' ') .. "*"; -- format the name  
if '' == args.dab then -- for |infobox caption=nodab  
return name; -- return the formatted name without the dab  
end  
return name .. dab; -- return the formatted name with the dab  
end  
end  
error_msg = error_msg .. ' no ship type in dab;';  

if '' == args.dab then -- for |infobox caption=nodab  
return table.concat (fragments, ' '), error_msg; -- return the unformatted name without the dab, and an error message  
end  
end  

return args.name, error_msg; -- return original un-formatted name with unformatted error message if any  
end  

--name= (required): a name is required; if missing or empty, this function returns an error message (may or may not be visible depending on where it is used)  
used in to provide a value for and to provide a value for |infobox caption=  

Optional parameters to support :  
|dab= – displays ship name without parenthetical disambiguator; use when |infobox caption=nodab  
|sclass=2 – for ship classes only; displays class name without italics (parameter name is loosely similar to which does the same thing); use when |infobox caption=class  
|adj=off – for ship classes only; displays class name as a noun (no hyphen, no ship type); use when |infobox caption=class  
Other optional parameters:  
|showerrs=yes – marginally useful; can display error messages if the module invocation is not buried in a template  

Values from the above parameters are placed in a table and that table passed as an argument in the call to do_ship_name_format.  

do_ship_name_format returns two strings: a name and an error message. If do_ship_name_format could format the name, it returns the formatted name and  
an empty string for the error message. If it could not format the name, do_ship_name_format returns the original name and an error message.  

Formatting of the error message, in response to |showerrs=yes is the responsibility of the calling function.  

function wpsu.ship_name_format  
local name = ''; -- destination of the formatted ship name  
local error_msg = ''; -- destination of any error message  

if not is_set (.args.name) then -- if a ship name not provided  
if 'yes' == .args.showerrs then -- and we're supposed to show errors  
error_msg = '<span>Empty name</span>'; -- return an empty string error message if there is no name  
end  
else  
name, error_msg = do_ship_name_format (.args); -- get formatted name and error message  
if is_set (error_msg) and 'yes' == .args.showerrs then -- if appropriate, show error message  
error_msg = '<span>' .. error_msg .. '</span>';  
else  
error_msg = ''; -- for concatenation  
end  
end  

return name .. error_msg; -- return name and error message  
end  

----------------------------< H N S A >----------------------------------------------------------------------  

Similar to , this code supports by attempting to construct a link to a ship article at the  
the Historic Nava Ships Association website.  

The template has the form:  

where:  
<page> is the name of the page at http://hnsa.org/hnsa-ships/<page>  
<name> (optional) is the name of the ship; if blank, the template uses the current page title; if a ship name, it is formatted  
from which this code produces:  
<name> at Historic Naval Ships Association  

function wpsu.hnsa  
local pframe = :getParent -- get arguments from calling template  
local ship_name = '';  
local error_msg = '';  
local article_title = mw.title.getCurrentTitle.text; -- fetch the article title  

if not is_set (pframe.args[1]) then  
return '<span>missing hsna page</span>';  
end  

local fmt_params = {['name']='', ['showerrs']=nil};  

if is_set (pframe.args.showerrs) then -- if showerrs set in template, override showerrs in #invoke:  
fmt_params.showerrs = pframe.args.showerrs; -- template value  
else  
fmt_params.showerrs = .args.showerrs; -- invoke value  
end  

if is_set (pframe.args[2]) then  
fmt_params.name = pframe.args[2];  
else  
fmt_params.name = article_title; -- use article title  
end  

ship_name, error_msg = do_ship_name_format (fmt_params);  

if is_set (error_msg) and is_set (pframe.args[2]) then -- if unable to format the name  
local escaped_name = pframe.args[2]:gsub("([%(%)%.%-])", "%%%1"); -- escape some of the Lua magic characters  
if pframe.args[2] == article_title or -- is name same as article title?  
nil ~= article_title:find ('%f[%a]' .. escaped_name .. '%f[%s]') or -- is name a word or words substring of article title?  
nil ~= article_title:find ('%f[%a]' .. escaped_name .. '$') then -- is name a word or words substring that ends article title?  
ship_name = "*" .. pframe.args[2] .. "*"; -- non-standard 'name'; perhaps just the name without prefix and dab;  
error_msg = ''; -- unset because we think we have a name  
end  
end  
if is_set (error_msg) and 'yes' == fmt_params.showerrs then  
error_msg = '<span>' .. error_msg .. '</span>';  
else  
error_msg = ''; -- unset so it doesn't diplay  
end  

local output = {  
'pframe.args[1,  
'/ ',  
ship_name,  
'] at Historic Naval Ships Association',  
error_msg,  
}  

return table.concat (output);  
end  

----------------------------< N A V S O U R C E >------------------------------------------------------------  

This version of the template was added as a test vehicle for do_ship_name_format.  

function wpsu.navsource  
local pframe = :getParent -- get arguments from calling template  
local ship_name = '';  
local error_msg = '';  
local article_title = mw.title.getCurrentTitle.text; -- fetch the article title  

if not is_set (pframe.args[1]) then  
return '<span>missing navsource URLcode</span>';  
end  

local fmt_params = {['name']='', ['showerrs']=nil};  

if is_set (pframe.args.showerrs) then -- if showerrs set in template, override showerrs in #invoke:  
fmt_params.showerrs = pframe.args.showerrs; -- template value  
else  
fmt_params.showerrs = .args.showerrs; -- invoke value  
end  

if is_set (pframe.args[2]) then  
fmt_params.name = pframe.args[2];  
else  
fmt_params.name = article_title; -- use article title  
end  

ship_name, error_msg = do_ship_name_format (fmt_params);  

if is_set (error_msg) and is_set (pframe.args[2]) then -- if unable to format the name  
local escaped_name = pframe.args[2]:gsub("([%(%)%.%-])", "%%%1"); -- escape some of the Lua magic characters  
if pframe.args[2] == article_title or -- is name same as article title?  
nil ~= article_title:find ('%f[%a]' .. escaped_name .. '%f[%s]') or -- is name a word or words substring of article title?  
nil ~= article_title:find ('%f[%a]' .. escaped_name .. '$') then -- is name a word or words substring that ends article title?  
ship_name = "*" .. pframe.args[2] .. "*"; -- non-standard 'name'; perhaps just the name without prefix and dab;  
error_msg = ''; -- unset because we think we have a name  
end  
end  
if is_set (error_msg) and 'yes' == fmt_params.showerrs then  
error_msg = '<span>' .. error_msg .. '</span>';  
else  
error_msg = ''; -- unset so it doesn't diplay  
end  

local output = {  
'pframe.args[1,  
'.htm Photo gallery] of ',  
ship_name,  
' at NavSource Naval History',  
error_msg,  
}  

return table.concat (output);  
end  

----------------------------< _ S H I P >--------------------------------------------------------------------  

This is a possible replacement for the template . It has better error detection and handling.  

local function _ship (prefix, name, dab, control, unlinked_prefix)  
local error_msg = '';  

if not is_set (control) then  
control = '';  
end  
-- dispose of error conditions straight away  
if not is_set (name) then -- this is the only required parameter  
error_msg = ' missing name';  
elseif not is_set (dab) and ('1' == control or '3' == control or '5' == control) then -- dab required when control value set to expect it  
error_msg = ' missing disambiguator';  
elseif not is_set (prefix) and ('5' == control or '6' == control) then -- prefix required when control value set to expect it  
error_msg = ' missing prefix';  
elseif '4' == control then -- displaying only the prefix  
error_msg = 'invalid control parameter: ' .. control;  
elseif is_set (control) then  
if 1 > tonumber (control) or 6 < tonumber (control) then -- control must be a number between 1 through 6  
error_msg = 'invalid control parameter: ' .. control;  
end  
elseif not is_set (prefix) and unlinked_prefix then -- prefix required when |up=yes  
error_msg = ' missing prefix';  
end  

if is_set (error_msg) then  
return '<span>' .. error_msg .. '</span>'; -- return an error message; don't bother with making a link  
end  

local link_name;  
local link = * .. link_name .. *;  
end  

----------------------------< W P S U . S H I P >------------------------------------------------------------  

This is a possible replacement for the template . It has better error detection and handling.  

This function is the externally accessible entry point for template , , , etc  

function wpsu.ship -- this version not supported from the template yet  
local prefix = mw.text.trim (.args[1] or ''); -- fetch positional parameters into named variables for readability  
local name = mw.text.trim (.args[2] or ''); -- stripped of leading and trailing whitespace  
local dab = mw.text.trim (.args[3] or ''); -- and and set to empty string (is that needed?)  
local control = .args[4];  
local unlinked_prefix = 'yes' == .args.up;  

return _ship (prefix, name, dab, control, unlinked_prefix);  
end  

----------------------------< L I S T _ E R R O R >----------------------------------------------------------  

Assembles an error message, the original parameter value and, if appropriate a category. The error message precedes  
the existing value of the parameter. If the first non-whitespace character in the parameter is a '*', set prefix to  
a '*' and sep to '\n'. For line-break lists, set prefix to empty string and sep to '  
'.  

Category is appended to the end of the returned value only for pages in article space.  

Inputs:  
prefix – a string of characters that precede the error message span; typically '' and '*'  
message – the error message to be displayed; goes inside the span  
sep – a string of characters that separates the span from the parameter value; typically '\n' and '  
'  
param_val – the unmodified parameter value  
showerrs – a boolean, true to display the error message text  

local function list_error (prefix, message, sep, param_val, showerrs)  
local err_msg = '%s<span>list error: %s (help)</span>%s%s%s';  
local category = '';  

if 0 == mw.title.getCurrentTitle.namespace then -- only categorize pages in article space  
category = '';  
end  
if true == showerrs then  
return string.format (err_msg, prefix, message, sep, param_val, category); -- put it all together  
else  
return param_val .. category;  
end  
end  

----------------------------< I N F O B O X _ L I S T S >----------------------------------------------------  

Mediawiki:Common.css imposes limitations on plain, unbulleted lists. The template does not render this correctly:  

The above renders without proper indents for items marked ** and ***.  

If the list is not wrapped in then the above list is rendered with bullets which is contrary to the Infobox ship usage guide.  

This code translates a bulleted list into an html unordered list:  

<ul>  
<li>Name 1</li>  
<li>Name 2</li>  
<ul>  
<li>Subname 2a</li>  
<ul>  
<li>Subname 2a1</li>  
</ul>  
<li>Subname 2b</li>  
</ul>  
<li>Name 3</li>  
</ul>  

There are rules:  
1. The parameter value must begin with a splat but may have leading and trailing whitespace.  
2. Each list item after the first must begin on a new line just as is required by normal bulleted lists.  
3. When adding a sublevel, the number of splats may increase by one and never more. This is illegal:  
- item
    - item
When any of these rules are violated, wpsu.unbulleted_list returns the original text and adds the article  
to Category:WPSHIPS:Infobox list errors. Error messaging in this function is somewhat sketchy so they are  
disabled. After initial adoption, better error messaging could/should be implemented.  

This function receives the content of one parameter:  
}  

function wpsu.unbulleted_list  
local showerrs = true; -- set to false to hide error messages  
local List_item_otag = '<li>'; -- hanging indent markup; everything moves with padding-; first line moved by neg indent  

if nil == .args[1]:match ('^%s*%*') then -- parameter value must begin with a splat (ignoring leading white space)  
if .args[1]:match ('<[%s/]*[Bb][Rr][%s/]*>') then -- if the parameter value has a list using variants of  
tag  
return list_error ('', '&lt;br /> list', '  
', .args[1], showerrs); -- return an error message with maintenance category  
elseif .args[1]:match ('.+\n%*') then -- if the parameter value has text followed by an unordered list  
return list_error ('', 'mixed text and list', '  
', .args[1], showerrs); -- return an error message with maintenance category  
end  
return .args[1]; -- return the parameter as is  
end  

local item_table = mw.text.split (mw.text.trim (.args[1]), '\n'); -- trim white space from end then make a table of bulleted items by splitting on newlines  
if 1 == #item_table then -- if only one bulleted item, no need for a list  
return (item_table[1]:gsub ('^%*%s*', '')); -- trim off the splat and any following white space and done  
end  

if item_table[1]:match ('^%*%*+') then -- if first list item uses more than one splat, that's an error  
return list_error ('*', 'too many * at start of list', '\n', .args[1], showerrs); -- return an error message with maintenance category  
end  

local html_table = {}; -- table to hold the html output  
local level = 1; -- used to indicate when a new <ul> is required  
local splats = 0; -- number of splats that start each item in the list  
local item = ''; -- the item text  

table.insert (html_table, '<ul>') -- this for first <ul> tag; sets no bullets and no indent  

for _,v in ipairs (item_table) do  
splats, item = v:match ('(%*+)%s*(.*)'); -- split the item into splats and item text  
if nil == splats then -- nil if there is an extra line between items  
return list_error ('*', 'list item missing markup', '\n', .args[1], showerrs); -- return an error message with maintenance category  
elseif '' == item then  
return list_error ('*', 'empty list item', '\n', .args[1], showerrs); -- return an error message with maintenance category  
elseif item:match ('^[;:]') then -- if the list item is mixed unordered list / description list markup (*:)  
return list_error ('*', 'mixed list type', '\n', .args[1], showerrs); -- return an error message with maintenance category  
end  

splats = splats:len; -- change string of splats into a number indicating how many splats there are  

if splats == level then -- if at the same level as previous item  
table.insert (html_table, List_item_otag .. item .. '</li>');  
elseif splats == level + 1 then -- number of splats can only increase by one  
level = splats; -- record the new level  
table.insert (html_table, '<ul>'); -- add a new sublist  
table.insert (html_table, List_item_otag .. item .. '</li>'); -- and the item  
elseif splats < level then -- from three splats to one splat for example  
while splats < level do  
table.insert (html_table, '</ul>'); -- close each sub <ul> until level and splats match  
level = level - 1;  
end  
table.insert (html_table, List_item_otag .. item .. '</li>'); -- add the item  
else -- jumping more than one level up – one splat to three splats for example – is an error  
return list_error ('*', 'too many asterisks', '\n', .args[1], showerrs); -- return an error message with maintenance category  
end  
end  

while 0 < level do  
table.insert (html_table, '</ul>'); -- close each <ul> until level counted down to zero  
level = level - 1;  
end  

return table.concat (html_table, '\n'); -- return the list as a string  
end  

--[=[-------------------------< I N F O B O X _ S H I P _ F L A G >--------------------------------------------  

Output of :  

Image syntax:  

This function standardizes the size of flag images in the infobox ship career header by simply overwriting the Size  
parameter value in the Image wikilink with |100x28px. This size leave a gap between the top and bottom of the flag image and  
the header edge. A similar -side gap of is supplied by .  

]=]  

function wpsu.infobox_ship_flag  
if not is_set (.args[1]) then -- if |Ship flag= not set  
return ''; -- return empty string  
end  

if .args[1]:match ('|[%s%dx]+px%s*') then -- is there a size positional parameter?  
.args[1] = .args[1]:gsub('|[%s%dx]+px%s*', '%|100x28px'); -- overwrite it with |100x28px  
else  
return '<span>malformed flag image</span>'  
end  
return .args[1]; -- return the modified image  
end  
return wpsu;