Шаблон:High-risk


Шаблон:Mi

Цей модуль та його підмодулі підтримують шаблони цитування {{cs1}} та {{cs2}}. Загалом, вони не призначені для безпосереднього виклику, а викликаються одним з основних шаблонів цитувань.

Наступні файли є частиною модуля, що забезпечує підтримку шаблонів цитувань cs1|2:

Модулі CS1|CS2
  У вжитку Пісочниця Опис
sysop Модуль:Citation/CS1 Модуль:Citation/CS1/пісочниця [редагувати] Функції рендерінгу та підтримки
Модуль:Citation/CS1/Configuration Модуль:Citation/CS1/Configuration/пісочниця [редагувати] Таблиці перекладу; функції-обробники помилок та ідентифікаторів
Модуль:Citation/CS1/Whitelist Модуль:Citation/CS1/Whitelist/пісочниця [редагувати] Перелік поточних, застарілих та таких, що більше не підтримуються, cs1|2 параметрів
Модуль:Citation/CS1/Date validation Модуль:Citation/CS1/Date validation/пісочниця [редагувати] Функції валідації форматування дат
Модуль:Citation/CS1/Identifiers Модуль:Citation/CS1/Identifiers/пісочниця [редагувати] Функції, які підтримують іменовані ідентифікатори (isbn, doi, pmid тощо)
Модуль:Citation/CS1/Utilities Модуль:Citation/CS1/Utilities/пісочниця [редагувати] Загальні функції і таблиці
Модуль:Citation/CS1/COinS Модуль:Citation/CS1/COinS/пісочниця [редагувати] Функції відображення (рендерінгу) метаданих шаблонів "cs1|2"
Модуль:Citation/CS1/styles.css Модуль:Citation/CS1/пісочниця/styles.css [редагувати] Стилі CSS, що застосовуються до шаблонів "cs1|2"
auto confirmed Module:Citation/CS1/Suggestions Модуль:Citation/CS1/Suggestions/пісочниця [редагувати] Перелік, який перевизначає загальновживані помилкові назви параметрів на правильні, підтримувані модулем назви параметрів


Інша документація:

Тести:

Див. також

ред.

Шаблон:Запозичений код


require ('strict');

--[[--------------------------< F O R W A R D   D E C L A R A T I O N S >--------------------------------------

each of these counts against the Lua upvalue limit

]]

--local validation;																-- functions in Module:Citation/CS1/Date_validation (додано буде в наступних оновленнях)

local utilities;																-- functions in Module:Citation/CS1/Utilities
local z = {};																	-- table of tables in Module:Citation/CS1/Utilities

local identifiers;																-- functions and tables in Module:Citation/CS1/Identifiers
local metadata;																	-- functions in Module:Citation/CS1/COinS
local cfg = {};																	-- table of configuration tables that are defined in Module:Citation/CS1/Configuration
local whitelist = {};															-- table of tables listing valid template parameter names; defined in Module:Citation/CS1/Whitelist

--[[------------------< P A G E   S C O P E   V A R I A B L E S >---------------

declare variables here that have page-wide scope that are not brought in from
other modules; that are created here and used here

]]

local added_deprecated_cat;														-- Boolean flag so that the category is added only once
local added_vanc_errs;															-- Boolean flag so we only emit one Vancouver error / category
local is_sandbox;																-- true when using sandbox modules to render citation

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

Locates and returns the first set value in a table of values where the order established in the table,
left-to-right (or top-to-bottom), is the order in which the values are evaluated.  Returns nil if none are set.

This version replaces the original 'for _, val in pairs do' and a similar version that used ipairs.  With the pairs
version the order of evaluation could not be guaranteed.  With the ipairs version, a nil value would terminate
the for-loop before it reached the actual end of the list.

]]

local function first_set (list, count)
	local i = 1;
	while i <= count do															-- loop through all items in list
		if utilities.is_set( list[i] ) then
			return list[i];														-- return the first set list member
		end
		i = i + 1;																-- point to next
	end
end

--[[--------------------------< A D D _ V A N C _ E R R O R >----------------------------------------------------

Adds a single Vancouver system error message to the template's output regardless of how many error actually exist.
To prevent duplication, added_vanc_errs is nil until an error message is emitted.

added_vanc_errs is a Boolean declared in page scope variables above

]]

local function add_vanc_error (source, position)
	if added_vanc_errs then return end
		
	added_vanc_errs = true;														-- note that we've added this category
	utilities.set_message ('err_vancouver', {source, position});
end

--[[--------------------------< I S _ S C H E M E >------------------------------------------------------------

does this thing that purports to be a URI scheme seem to be a valid scheme?  The scheme is checked to see if it
is in agreement with http://tools.ietf.org/html/std66#section-3.1 which says:
	Scheme names consist of a sequence of characters beginning with a
   letter and followed by any combination of letters, digits, plus
   ("+"), period ("."), or hyphen ("-").

returns true if it does, else false

]]

local function is_scheme (scheme)
	return scheme and scheme:match ('^%a[%a%d%+%.%-]*:');						-- true if scheme is set and matches the pattern
end


--[=[-------------------------< I S _ D O M A I N _ N A M E >--------------------------------------------------

Does this thing that purports to be a domain name seem to be a valid domain name?

Syntax defined here: http://tools.ietf.org/html/rfc1034#section-3.5
BNF defined here: https://tools.ietf.org/html/rfc4234
Single character names are generally reserved; see https://tools.ietf.org/html/draft-ietf-dnsind-iana-dns-01#page-15;
	see also [[Single-letter second-level domain]]
list of TLDs: https://www.iana.org/domains/root/db

RFC 952 (modified by RFC 1123) requires the first and last character of a hostname to be a letter or a digit.  Between
the first and last characters the name may use letters, digits, and the hyphen.

Also allowed are IPv4 addresses. IPv6 not supported

domain is expected to be stripped of any path so that the last character in the last character of the TLD.  tld
is two or more alpha characters.  Any preceding '//' (from splitting a URL with a scheme) will be stripped
here.  Perhaps not necessary but retained in case it is necessary for IPv4 dot decimal.

There are several tests:
	the first character of the whole domain name including subdomains must be a letter or a digit
	internationalized domain name (ASCII characters with .xn-- ASCII Compatible Encoding (ACE) prefix xn-- in the TLD) see https://tools.ietf.org/html/rfc3490
	single-letter/digit second-level domains in the .org, .cash, and .today TLDs
	q, x, and z SL domains in the .com TLD
	i and q SL domains in the .net TLD
	single-letter SL domains in the ccTLDs (where the ccTLD is two letters)
	two-character SL domains in gTLDs (where the gTLD is two or more letters)
	three-plus-character SL domains in gTLDs (where the gTLD is two or more letters)
	IPv4 dot-decimal address format; TLD not allowed

returns true if domain appears to be a proper name and TLD or IPv4 address, else false

]=]

local function is_domain_name (domain)
	if not domain then
		return false;															-- if not set, abandon
	end
	
	domain = domain:gsub ('^//', '');											-- strip '//' from domain name if present; done here so we only have to do it once
	
	if not domain:match ('^[%w]') then											-- first character must be letter or digit
		return false;
	end

	if domain:match ('^%a+:') then												-- hack to detect things that look like s:Page:Title where Page: is namespace at Wikisource
		return false;
	end

	local patterns = {															-- patterns that look like URLs
		'%f[%w][%w][%w%-]+[%w]%.%a%a+$',										-- three or more character hostname.hostname or hostname.tld
		'%f[%w][%w][%w%-]+[%w]%.xn%-%-[%w]+$',									-- internationalized domain name with ACE prefix
		'%f[%a][qxz]%.com$',													-- assigned one character .com hostname (x.com times out 2015-12-10)
		'%f[%a][iq]%.net$',														-- assigned one character .net hostname (q.net registered but not active 2015-12-10)
		'%f[%w][%w]%.%a%a$',													-- one character hostname and ccTLD (2 chars)
		'%f[%w][%w][%w]%.%a%a+$',												-- two character hostname and TLD
		'^%d%d?%d?%.%d%d?%d?%.%d%d?%d?%.%d%d?%d?',								-- IPv4 address
		}

	for _, pattern in ipairs (patterns) do										-- loop through the patterns list
		if domain:match (pattern) then
			return true;														-- if a match then we think that this thing that purports to be a URL is a URL
		end
	end

	for _, d in ipairs (cfg.single_letter_2nd_lvl_domains_t) do					-- look for single letter second level domain names for these top level domains
		if domain:match ('%f[%w][%w]%.' .. d) then
			return true
		end
	end
	return false;																-- no matches, we don't know what this thing is
end


--[[--------------------------< I S _ U R L >------------------------------------------------------------------

returns true if the scheme and domain parts of a URL appear to be a valid URL; else false.

This function is the last step in the validation process.  This function is separate because there are cases that
are not covered by split_url(), for example is_parameter_ext_wikilink() which is looking for bracketted external
wikilinks.

]]

local function is_url (scheme, domain)
	if utilities.is_set (scheme) then											-- if scheme is set check it and domain
		return is_scheme (scheme) and is_domain_name (domain);
	else
		return is_domain_name (domain);											-- scheme not set when URL is protocol-relative
	end
end

--[[--------------------------< S P L I T _ U R L >------------------------------------------------------------

Split a URL into a scheme, authority indicator, and domain.

First remove Fully Qualified Domain Name terminator (a dot following TLD) (if any) and any path(/), query(?) or fragment(#).

If protocol-relative URL, return nil scheme and domain else return nil for both scheme and domain.

When not protocol-relative, get scheme, authority indicator, and domain.  If there is an authority indicator (one
or more '/' characters immediately following the scheme's colon), make sure that there are only 2.

Any URL that does not have news: scheme must have authority indicator (//).  TODO: are there other common schemes
like news: that don't use authority indicator?

Strip off any port and path;

]]

local function split_url (url_str)
	local scheme, authority, domain;
	
	url_str = url_str:gsub ('([%a%d])%.?[/%?#].*$', '%1');						-- strip FQDN terminator and path(/), query(?), fragment (#) (the capture prevents false replacement of '//')

	if url_str:match ('^//%S*') then											-- if there is what appears to be a protocol-relative URL
		domain = url_str:match ('^//(%S*)')
	elseif url_str:match ('%S-:/*%S+') then										-- if there is what appears to be a scheme, optional authority indicator, and domain name
		scheme, authority, domain = url_str:match ('(%S-:)(/*)(%S+)');			-- extract the scheme, authority indicator, and domain portions
		if utilities.is_set (authority) then
			authority = authority:gsub ('//', '', 1);							-- replace place 1 pair of '/' with nothing;
			if utilities.is_set(authority) then									-- if anything left (1 or 3+ '/' where authority should be) then
				return scheme;													-- return scheme only making domain nil which will cause an error message
			end
		else
			if not scheme:match ('^news:') then									-- except for news:..., MediaWiki won't link URLs that do not have authority indicator; TODO: a better way to do this test?
				return scheme;													-- return scheme only making domain nil which will cause an error message
			end
		end
		domain = domain:gsub ('(%a):%d+', '%1');								-- strip port number if present
	end
	
	return scheme, domain;
end


--[[--------------------------< L I N K _ P A R A M _ O K >---------------------------------------------------

checks the content of |title-link=, |series-link=, |author-link=, etc. for properly formatted content: no wikilinks, no URLs

Link parameters are to hold the title of a Wikipedia article, so none of the WP:TITLESPECIALCHARACTERS are allowed:
	# < > [ ] | { } _
except the underscore which is used as a space in wiki URLs and # which is used for section links

returns false when the value contains any of these characters.

When there are no illegal characters, this function returns TRUE if value DOES NOT appear to be a valid URL (the
|<param>-link= parameter is ok); else false when value appears to be a valid URL (the |<param>-link= parameter is NOT ok).

]]

local function link_param_ok (value)
	local scheme, domain;
	if value:find ('[<>%[%]|{}]') then											-- if any prohibited characters
		return false;
	end

	scheme, domain = split_url (value);											-- get scheme or nil and domain or nil from URL; 
	return not is_url (scheme, domain);											-- return true if value DOES NOT appear to be a valid URL
end


--[[--------------------------< L I N K _ T I T L E _ O K >---------------------------------------------------

Use link_param_ok() to validate |<param>-link= value and its matching |<title>= value.

|<title>= may be wiki-linked but not when |<param>-link= has a value.  This function emits an error message when
that condition exists

check <link> for inter-language interwiki-link prefix.  prefix must be a MediaWiki-recognized language
code and must begin with a colon.

]]

local function link_title_ok (link, lorig, title, torig)
	local orig;
	if utilities.is_set (link) then 											-- don't bother if <param>-link doesn't have a value
		if not link_param_ok (link) then										-- check |<param>-link= markup
			orig = lorig;														-- identify the failing link parameter
		elseif title:find ('%[%[') then											-- check |title= for wikilink markup
			orig = torig;														-- identify the failing |title= parameter
		elseif link:match ('^%a+:') then										-- if the link is what looks like an interwiki
			local prefix = link:match ('^(%a+):'):lower();						-- get the interwiki prefix

			if cfg.inter_wiki_map[prefix] then									-- if prefix is in the map, must have preceding colon
				orig = lorig;													-- flag as error
			end
		end
	end

	if utilities.is_set (orig) then
		link = '';																-- unset
		utilities.set_message ('err_bad_paramlink', orig);						-- URL or wikilink in |title= with |title-link=;
	end
	
	return link;																-- link if ok, empty string else
end

-- Wraps a string using a message_list configuration taking one argument
local function wrap( key, str )
    if not utilities.is_set( str ) then
        return "";
    elseif utilities.in_array( key, { 'italic-title', 'trans-italic-title' } ) then
        str = utilities.safe_for_italics( str );
    end
    return utilities.substitute( cfg.messages[key], {str} );
end

--[[--------------------------< W R A P _ M S G >--------------------------------------------------------------

Applies additional message text to various parameter values. Supplied string is wrapped using a message_list
configuration taking one argument.  Supports lower case text for {{citation}} templates.  Additional text taken
from citation_config.messages - the reason this function is similar to but separate from wrap_style().

]]

local function wrap_msg (key, str, lower)
	if not utilities.is_set ( str ) then
		return "";
	end
	if true == lower then
		local msg;
		msg = cfg.messages[key]:ulower();										-- set the message to lower case before 
		return utilities.substitute ( msg, str );								-- including template text
	else
		return utilities.substitute ( cfg.messages[key], str );
	end		
end

--[[--------------------------< I S _ T A G  >------------------------------------------------------------------
 
 Ця функція перевіряє довжуни поданого параметру мови і його підтримку модулем. Якщо він довжиною від 2 до 7 та 
 є в cfg.supported_langauge_codes, то повертається true, якщо ні, то — false.
 
]]

local function is_tag (lang_param)
	if #lang_param>=2 and #lang_param<=7 and utilities.in_array(lang_param, cfg.supported_langauge_codes[#lang_param]) then -- перевіряємо чи вказано мовний код і чи підтримується він модулем
		return true																--якщо код мови, що підтримується, то повертаємо true
	else
		return false															--якщо не код мови або код мови, що не підтримується, то повертаємо false
	end	
end

--[[--------------------------< L A N G U A G E _ P A R A M E T E R  >-------------------------------------------

Ця функція впроваджує роботу шаблонів {{ref-lang}} та {{lg}} в межах самого модулю для унукнення виходу за межі
розкриття шаблонів. Якщо значенням змінної is_dstu є true, то оформлення відбувається за шаблон {{lg}}, в іншому 
випадку оформлення відбувається за {{ref-lang}}.

Змінна lang_code містить мовний код мови, що передано в параметр |language=.

]]

local function language_parameter(lang, is_dstu)
	local name;																	-- the language name
	local wraped_name;
	local language_list = {};													-- table of language names to be rendered
	local language_list_wraped = {};											-- table of language names to be rendered
	local language_string
	local names_t = {};															-- table made from the value assigned to |language=
	
	names_t = mw.text.split (lang, '%s*,%s*');									-- names should be a comma separated list
	
	for _, lang in ipairs (names_t) do											-- reuse lang here because we don't yet know if lang is a language name or a language tag
	
		local is_tag = is_tag (lang)												-- містить значення чи є вказаний параметр тегом
		
		if is_tag then -- перевіряємо чи вказано мовний код і чи підтримується він модулем
			local class, tip, shorten_name;											--оголошуємо змінні
			local lang_t = cfg.language_table[lang]									--отримуємо рядок таблиці з cfg.language_table відповідно до вказаного мовного коду
		
			if is_dstu then															--якщо стиль оформлення дсту, то
				class = 'cs1-ref-lg';												--вказуємо клас за яким буде оформлено загальний <span>
				local formated_short;
				if utilities.is_set(lang_t.link) then								--якщо є параметр link заповнений, то
					formated_short = utilities.make_wikilink (lang_t.link, utilities.substitute (cfg.presentation['ref-text'], {'cs1-ref-lg-text', lang_t.short})) --стоворюємо вікіпосилання, взявши назву статті та скорочену назву мови з таблиці, а також огортаємо останню <span> з відповідними каласами (це реалізація шаблону {{masklink}})
				else																--якщо не заповнений, то
					formated_short = lang_t.short									--просто передаємо скорочену назву (не має назви статті на яку потрібно посилатися, тому не має сенсу робити те все оформлення)
				end
				shorten_name = wrap_msg( 'dstulanguage', formated_short)			--огортаємо відформатовану скорочену назву одинарними квадратними дужками
				tip = "мова: " .. lang_t.nominative									--формуємо підказку, що виводитиметься при наведені миші
			else																	--якщо стиль оформлення не дсту, то
				class = 'cs1-ref-lang';												--вказуємо клас за яким буде оформлено загальний <span>
				shorten_name = wrap_msg( 'language', lang_t.short)					--огортаємо скорочену назву одинарними круглими дужками
				if lang_t.is_noun then												--якщо назва іменник, то
					tip = "мовою " .. utilities.is_set(lang_t.instrumental) and lang_t.instrumental or lang_t.nominative --формуємо підказку, де «мовою» йде перед назвою мови, назву мови вибираємо залежно від того чи вкзано орудний відмінок для мови
				else																--якщо назва прикметник, то
					tip = lang_t.instrumental .. " мовою"							--формуємо підказку, де «мовою» йде після назви мови та використовуємо назву мови в орудному відмінку
				end	
			end
		
		local wraped =  utilities.substitute (cfg.presentation['ref-lang'], {class, tip, shorten_name}) --огортаємо shorten_name загальним <span> з відповідним класом і підказкою
		table.insert (language_list_wraped, wraped)
--		error(language_list_wraped[1])
																				--повертаємо повністю відформатований рядок
		else
			table.insert (language_list, lang)
		end
	end	
	
	if #language_list > 0 then
    	name =  wrap_msg( is_dstu and 'dstulanguage' or 'language', utilities.make_sep_list (#language_list, language_list) );
	else
		name = "";
	end
	
	if #language_list_wraped > 0 then
		wraped_name = utilities.make_sep_list (#language_list_wraped, language_list_wraped, " ", " ");
	else
		wraped_name = "";
	end	
	
	language_string =  (is_dstu and cfg.presentation['sep_colon_dstu2006'] or ' ') .. name .. " " .. wraped_name;
	
--	if (1 == #language_list) and (lang_subtag == cfg.this_wiki_code) then		-- when only one language, find lang name in this wiki lang name; for |language=en-us, 'English' in 'American English'
--		return '';																-- if one language and that language is this wiki's return an empty string (no annotation)
--	end
	
	return language_string
end

--convert date from 'YYYY-MM-DD' format to 'DD month YYYY' format
local monthsDaysCounts = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
local englishMonthNames = 
{
	"January", "February", 
	"March", "April", "May", 
	"June", "July", "August", 
	"September", "October", "November", 
	"December"
}
local ukrainianMonthNamesGen = 
{
	'січня', 'лютого', 
	'березня', 'квітня', 'травня', 
	'червня', 'липня', 'серпня', 
	'вересня', 'жовтня', 'листопада', 
	'грудня'
}

local function ParseDateIfPossible(dateString, is_embargo_pmc)
	local year, month, day = string.match(dateString, "^(%d%d%d%d)%-(%d%d)%-(%d%d)$")
	if year then
		local day_int, month_int = tonumber(day), tonumber(month)
		if type(day_int)~='number' or type(month_int)~='number' 
		 or month_int<1 or month_int>12
		 or day_int<1 or day_int>monthsDaysCounts[month_int] then
			return dateString
		end
		return day_int..' '..ukrainianMonthNamesGen[month_int]..' '..year
	end
	
	local month, day, year = string.match(dateString, "^(%a+) +([1-9]%d?), (%d%d%d%d)$")
	if not month then
		day, month, year = string.match(dateString, "^+([1-9]%d?) (%a+) (%d%d%d%d)$")
	end
	
	if is_embargo_pmc then
		day, month, year = mw.ustring.match(dateString, "^([1-9]%d?) (%a+) (%d%d%d%d)$")
	end
	
	if day and month then
		local month_int
		
		if is_embargo_pmc then
			 month_int = utilities.in_array(month, ukrainianMonthNamesGen)
		else
			month_int = utilities.in_array(month, englishMonthNames)
		end	
		
		if not month_int then return dateString end
		local day_int = tonumber(day)
		
		if is_embargo_pmc then
			return day_int..' '..englishMonthNames[month_int]..' '..year
		end	
		
		return day_int..' '..ukrainianMonthNamesGen[month_int]..' '..year
	end
	
	return dateString
end

--[[
Argument wrapper.  This function provides support for argument 
mapping defined in the configuration file so that multiple names
can be transparently aliased to single internal variable.
]]
local function argument_wrapper( args )
    local origin = {};
    
    return setmetatable({
        ORIGIN = function( self, k )
            local dummy = self[k]; --force the variable to be loaded.
            return origin[k];
        end
    },
    {
        __index = function ( tbl, k )
            if origin[k] ~= nil then
                return nil;
            end
            
            local args, list, v = args, cfg.aliases[k];
            
            if type( list ) == 'table' then
				v, origin[k] = utilities.select_one ( args, list, 'err_redundant_parameters' );
				if origin[k] == nil then
					origin[k] = '';												-- Empty string, not nil
				end
			elseif list ~= nil then
				v, origin[k] = args[list], list;
			else
				-- maybe let through instead of raising an error?
				-- v, origin[k] = args[k], k;
				error( cfg.messages['unknown_argument_map'] .. ': ' .. k);
			end
            
            -- Empty strings, not nil;
            if v == nil then
                v = cfg.defaults[k] or "";
                origin[k] = '';
            end
            
            tbl = rawset( tbl, k, v );
            return v;
        end,
    });
end

--[[--------------------------< D E P R E C A T E D _ P A R A M E T E R >--------------------------------------

Categorize and emit an error message when the citation contains one or more deprecated parameters.  The function includes the
offending parameter name to the error message.  Only one error message is emitted regardless of the number of deprecated
parameters in the citation.

added_deprecated_cat is a Boolean declared in page scope variables above

]]

local function deprecated_parameter(name)
	if not added_deprecated_cat then
		added_deprecated_cat = true;											-- note that we've added this category
		utilities.set_message ('err_deprecated_params', {name});				-- add error message
	end
end	

--[[
Determines whether an URL string is valid

At present the only check is whether the string appears to 
be prefixed with a URI scheme.  It is not determined whether 
the URI scheme is valid or whether the URL is otherwise well 
formed.
]]

local function check_url( url_str )
    -- Protocol-relative or URL scheme
    return url_str:sub(1,2) == "//" or url_str:match( "^[^/]*:" ) ~= nil;
end

--[[--------------------------< S A F E _ F O R _ U R L >------------------------------------------------------

Escape sequences for content that will be used for URL descriptions

]]

local function safe_for_url( str )
    if str:match( "%[%[.-%]%]" ) ~= nil then 
        utilities.set_message( 'err_wikilink_in_url', {});
    end
    
    return str:gsub( '[%[%]\n]', {    
        ['['] = '&#91;',
        [']'] = '&#93;',
        ['\n'] = ' ' } );
end

--[=[-------------------------< I S _ G E N E R I C >----------------------------------------------------------

Compares values assigned to various parameters according to the string provided as <item> in the function call.
<item> can have on of two values:
	'generic_names' – for name-holding parameters: |last=, |first=, |editor-last=, etc
	'generic_titles' – for |title=

There are two types of generic tests.  The 'accept' tests look for a pattern that should not be rejected by the
'reject' test.  For example,
	|author=[[John Smith (author)|Smith, John]]
would be rejected by the 'author' reject test.  But piped wikilinks with 'author' disambiguation should not be
rejected so the 'accept' test prevents that from happening.  Accept tests are always performed before reject
tests.

Each of the 'accept' and 'reject' sequence tables hold tables for en.wiki (['en']) and local.wiki (['local'])
that each can hold a test sequence table  The sequence table holds, at index [1], a test pattern, and, at index
[2], a boolean control value.  The control value tells string.find() or mw.ustring.find() to do plain-text search (true)
or a pattern search (false).  The intent of all this complexity is to make these searches as fast as possible so
that we don't run out of processing time on very large articles.

Returns
	true when a reject test finds the pattern or string
	false when an accept test finds the pattern or string
	nil else

]=]

local function is_generic (item, value, wiki)
	local test_val;
	local str_lower = {															-- use string.lower() for en.wiki (['en']) and use mw.ustring.lower() or local.wiki (['local'])
		['en'] = string.lower,
		['local'] = mw.ustring.lower,
		}
	local str_find = {															-- use string.find() for en.wiki (['en']) and use mw.ustring.find() or local.wiki (['local'])
		['en'] = string.find,
		['local'] = mw.ustring.find,
		}

	local function test (val, test_t, wiki)										-- local function to do the testing; <wiki> selects lower() and find() functions
		val = test_t[2] and str_lower[wiki](value) or val;						-- when <test_t[2]> set to 'true', plaintext search using lowercase value
		return str_find[wiki] (val, test_t[1], 1, test_t[2]);					-- return nil when not found or matched
	end
		
	local test_types_t = {'accept', 'reject'};									-- test accept patterns first, then reject patterns
	local wikis_t = {'en', 'local'};											-- do tests for each of these keys; en.wiki first, local.wiki second

	for _, test_type in ipairs (test_types_t) do								-- for each test type
		for _, generic_value in pairs (cfg.special_case_translation[item][test_type]) do	-- spin through the list of generic value fragments to accept or reject
			for _, wiki in ipairs (wikis_t) do
				if generic_value[wiki] then
					if test (value, generic_value[wiki], wiki) then				-- go do the test
						return ('reject' == test_type);							-- param value rejected, return true; false else
					end
				end
			end
		end
	end
end

--[[--------------------------< E X T E R N A L _ L I N K >----------------------------------------------------

Format an external link with error checking

]]

local function external_link (URL, label, source, access)
	local base_url;
	
    if not utilities.is_set (label) then
        label = URL;
        if utilities.is_set (source) then
            utilities.set_message ('err_bare_url_missing_title', { wrap( 'parameter', source ) }, false, " ");
        else
            error( cfg.messages["bare_url_no_origin"] );
        end            
    end
    if not check_url( URL ) then
        utilities.set_message( 'err_bad_url', {}, false, " " );
    end
    
    base_url = table.concat({ "[", URL, " ", safe_for_url( label ), "]"})
    
    if utilities.is_set (access) then											-- access level (subscription, registration, limited)
		base_url = utilities.substitute (cfg.presentation['ext-link-access-signal'], {cfg.presentation[access].class, cfg.presentation[access].title, base_url});	-- add the appropriate icon
	end
    
    return base_url;
end

--[[--------------------------< F O R M A T _ S C R I P T _ V A L U E >----------------------------------------

|script-title= holds title parameters that are not written in Latin-based scripts: Chinese, Japanese, Arabic, Hebrew, etc. These scripts should
not be italicized and may be written right-to-left.  The value supplied by |script-title= is concatenated onto Title after Title has been wrapped
in italic markup.

Regardless of language, all values provided by |script-title= are wrapped in <bdi>...</bdi> tags to isolate RTL languages from the English left to right.

|script-title= provides a unique feature.  The value in |script-title= may be prefixed with a two-character ISO 639-1 language code and a colon:
	|script-title=ja:*** *** (where * represents a Japanese character)
Spaces between the two-character code and the colon and the colon and the first script character are allowed:
	|script-title=ja : *** ***
	|script-title=ja: *** ***
	|script-title=ja :*** ***
Spaces preceding the prefix are allowed: |script-title = ja:*** ***

The prefix is checked for validity.  If it is a valid ISO 639-1 language code, the lang attribute (lang="ja") is added to the <bdi> tag so that browsers can
know the language the tag contains.  This may help the browser render the script more correctly.  If the prefix is invalid, the lang attribute
is not added.  At this time there is no error message for this condition.

Supports |script-title=, |script-chapter=, |script-<periodical>=

]]

local function format_script_value (script_value, script_param)
	local lang='';																-- initialize to empty string
	local name;
	if script_value:match('^%l%l%l?%s*:') then									-- if first 3 or 4 non-space characters are script language prefix
		lang = script_value:match('^(%l%l%l?)%s*:%s*%S.*');						-- get the language prefix or nil if there is no script
		if not utilities.is_set (lang) then
			utilities.set_message ('err_script_parameter', {script_param, cfg.err_msg_supl['missing title part']});		-- prefix without 'title'; add error message
			return '';															-- script_value was just the prefix so return empty string
		end
																				-- if we get this far we have prefix and script
		name = cfg.lang_tag_remap[lang] or mw.language.fetchLanguageName( lang, cfg.this_wiki_code );	-- get language name so that we can use it to categorize
		if utilities.is_set (name) then											-- is prefix a proper ISO 639-1 language code?
			script_value = script_value:gsub ('^%l+%s*:%s*', '');				-- strip prefix from script
																				-- is prefix one of these language codes?
			if utilities.in_array (lang, cfg.script_lang_codes) then
				utilities.add_prop_cat ('script', {name, lang})
			else
				utilities.set_message ('err_script_parameter', {script_param, cfg.err_msg_supl['unknown language code']});	-- unknown script-language; add error message
			end
			lang = ' lang="' .. lang .. '" ';									-- convert prefix into a lang attribute
		else
			utilities.set_message ('err_script_parameter', {script_param, cfg.err_msg_supl['invalid language code']});		-- invalid language code; add error message
			lang = '';															-- invalid so set lang to empty string
		end
	else
		utilities.set_message ('err_script_parameter', {script_param, cfg.err_msg_supl['missing prefix']});				-- no language code prefix; add error message
	end
	script_value = utilities.substitute (cfg.presentation['bdi'], {lang, script_value});	-- isolate in case script is RTL

	return script_value;
end


--[[--------------------------< S C R I P T _ C O N C A T E N A T E >------------------------------------------

Initially for |title= and |script-title=, this function concatenates those two parameter values after the script
value has been wrapped in <bdi> tags.

]]

local function script_concatenate (title, script, script_param)
	if utilities.is_set (script) then
		script = format_script_value (script, script_param);					-- <bdi> tags, lang attribute, categorization, etc.; returns empty string on error
		if utilities.is_set (script) then
			title = title .. ' ' .. script;										-- concatenate title and script title
		end
	end
	return title;
end

-- Gets the display text for a wikilink like [[A|B]] or [[B]] gives B
local function remove_wiki_link( str )
    return (str:gsub( "%[%[([^%[%]]*)%]%]", function(l)
        return l:gsub( "^[^|]*|(.*)$", "%1" ):gsub("^%s*(.-)%s*$", "%1");
    end));
end

-- Converts a hyphen to a dash
local function hyphen_to_dash( str )
    if not utilities.is_set(str) or str:match( "[%[%]{}<>]" ) ~= nil then
        return str;
    end    
    return str:gsub( '-', '–' );
end

--[[----------------< W I K I S O U R C E _ U R L _ M A K E >-------------------

Makes a Wikisource URL from Wikisource interwiki-link.  Returns the URL and appropriate
label; nil else.

str is the value assigned to |chapter= (or aliases) or |title= or |title-link=

]]

local function wikisource_url_make (str)
	local wl_type, D, L;
	local ws_url, ws_label;
	local wikisource_prefix = table.concat ({'https://', cfg.this_wiki_code, '.wikisource.org/wiki/'});

	wl_type, D, L = utilities.is_wikilink (str);								-- wl_type is 0 (not a wikilink), 1 (simple wikilink), 2 (complex wikilink)

	if 0 == wl_type then														-- not a wikilink; might be from |title-link=
		str = D:match ('^[Ww]ikisource:(.+)') or D:match ('^[Ss]:(.+)');		-- article title from interwiki link with long-form or short-form namespace
		if utilities.is_set (str) then
			ws_url = table.concat ({											-- build a Wikisource URL
				wikisource_prefix,												-- prefix
				str,															-- article title
				});
			ws_label = str;														-- label for the URL
		end
	elseif 1 == wl_type then													-- simple wikilink: [[Wikisource:ws article]]
		str = D:match ('^[Ww]ikisource:(.+)') or D:match ('^[Ss]:(.+)');		-- article title from interwiki link with long-form or short-form namespace
		if utilities.is_set (str) then
			ws_url = table.concat ({											-- build a Wikisource URL
				wikisource_prefix,												-- prefix
				str,															-- article title
				});
			ws_label = str;														-- label for the URL
		end
	elseif 2 == wl_type then													-- non-so-simple wikilink: [[Wikisource:ws article|displayed text]] ([[L|D]])
		str = L:match ('^[Ww]ikisource:(.+)') or L:match ('^[Ss]:(.+)');		-- article title from interwiki link with long-form or short-form namespace
		if utilities.is_set (str) then
			ws_label = D;														-- get ws article name from display portion of interwiki link
			ws_url = table.concat ({											-- build a Wikisource URL
				wikisource_prefix,												-- prefix
				str,															-- article title without namespace from link portion of wikilink
				});
		end
	end

	if ws_url then
		ws_url = mw.uri.encode (ws_url, 'WIKI');								-- make a usable URL
		ws_url = ws_url:gsub ('%%23', '#');										-- undo percent-encoding of fragment marker
	end

	return ws_url, ws_label, L or D;											-- return proper URL or nil and a label or nil
end

--[[----------------< F O R M A T _ P E R I O D I C A L >-----------------------

Format the three periodical parameters: |script-<periodical>=, |<periodical>=,
and |trans-<periodical>= into a single Periodical meta-parameter.

]]

local function format_periodical (script_periodical, script_periodical_source, periodical, trans_periodical, trans_italic_title)

	if not utilities.is_set (periodical) then
		periodical = '';														-- to be safe for concatenation
	else
		periodical = utilities.wrap_style ('italic-title', periodical);			-- style 
	end

	periodical = script_concatenate (periodical, script_periodical, script_periodical_source);	-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped

	if utilities.is_set (trans_periodical) then
		trans_periodical = utilities.wrap_style (trans_italic_title, trans_periodical);
		if utilities.is_set (periodical) then
			periodical = periodical .. ' ' .. trans_periodical;
		else																	-- here when trans-periodical without periodical or script-periodical
			periodical = trans_periodical;
			utilities.set_message ('err_trans_missing_title', {'periodical'});
		end
	end

	return periodical;
end

--[[------------------< F O R M A T _ C H A P T E R _ T I T L E >---------------

Format the four chapter parameters: |script-chapter=, |chapter=, |trans-chapter=,
and |chapter-url= into a single chapter meta- parameter (chapter_url_source used
for error messages).

]]

local function format_chapter_title (script_chapter, script_chapter_source, chapter, chapter_source, trans_chapter, trans_chapter_source, chapter_url, chapter_url_source, no_quotes, access)
	local ws_url, ws_label, L = wikisource_url_make (chapter);					-- make a wikisource URL and label from a wikisource interwiki link
	if ws_url then
		ws_label = ws_label:gsub ('_', ' ');									-- replace underscore separators with space characters
		chapter = ws_label;
	end

	if not utilities.is_set (chapter) then
		chapter = '';															-- to be safe for concatenation
	else
		if false == no_quotes then
		--	chapter = kern_quotes (chapter);									-- if necessary, separate chapter title's leading and trailing quote marks from module provided quote marks
			chapter = utilities.wrap_style ('quoted-title', chapter);
		end
	end

	chapter = script_concatenate (chapter, script_chapter, script_chapter_source);	-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped

	if utilities.is_set (chapter_url) then
		chapter = external_link (chapter_url, chapter, chapter_url_source, access);	-- adds bare_url_missing_title error if appropriate
	elseif ws_url then
		chapter = external_link (ws_url, chapter .. '&nbsp;', 'ws link in chapter');	-- adds bare_url_missing_title error if appropriate; space char to move icon away from chap text; TODO: better way to do this?
		chapter = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, chapter});				
	end

	if utilities.is_set (trans_chapter) then
		trans_chapter = utilities.wrap_style ('trans-quoted-title', trans_chapter);
		if utilities.is_set (chapter) then
			chapter = chapter .. ' ' .. trans_chapter;
		else																	-- here when trans_chapter without chapter or script-chapter
			chapter = trans_chapter;
			chapter_source = trans_chapter_source:match ('trans%-?(.+)');		-- when no chapter, get matching name from trans-<param>
			utilities.set_message ('err_trans_missing_title', {chapter_source});
		end
	end

	return chapter;
end

--[[--------------------------< S E T _ T I T L E T Y P E >---------------------

This function sets default title types (equivalent to the citation including
|type=<default value>) for those templates that have defaults. Also handles the
special case where it is desirable to omit the title type from the rendered citation
(|type=none).

]]

local function set_titletype (cite_class, title_type)
	if utilities.is_set (title_type) then
		if 'none' == cfg.keywords_xlate[title_type] then
			title_type = '';													-- if |type=none then type parameter not displayed
		end
		return title_type;														-- if |type= has been set to any other value use that value
	end

	return cfg.title_types [cite_class] or '';									-- set template's default title type; else empty string for concatenation
end

--[[--------------------------< S A F E _ J O I N >-----------------------------

Joins a sequence of strings together while checking for duplicate separation characters.

]]

local function safe_join( tbl, duplicate_char, dstu_sepc )
	local f = {};																-- create a function table appropriate to type of 'duplicate character'
		if 1 == #duplicate_char then											-- for single byte ASCII characters use the string library functions
			f.gsub = string.gsub
			f.match = string.match
			f.sub = string.sub
		else																	-- for multi-byte characters use the ustring library functions
			f.gsub = mw.ustring.gsub
			f.match = mw.ustring.match
			f.sub = mw.ustring.sub
		end

	local str = '';																-- the output string
	local comp = '';															-- what does 'comp' mean?
	local end_chr = '';
	local trim;
	for _, value in ipairs( tbl ) do
		if value == nil then value = ''; end
		
		if str == '' then														-- if output string is empty
			str = value;														-- assign value to it (first time through the loop)
		elseif value ~= '' then
			if value:sub(1, 1) == '<' then										-- special case of values enclosed in spans and other markup.
				comp = value:gsub( "%b<>", "" );								-- remove HTML markup (<span>string</span> -> string)
			else
				comp = value;
			end
																				-- typically duplicate_char is sepc
			if f.sub(comp, 1, 1) == duplicate_char then							-- is first character same as duplicate_char? why test first character?
																				--   Because individual string segments often (always?) begin with terminal punct for the
																				--   preceding segment: 'First element' .. 'sepc next element' .. etc.?
				trim = false;
				end_chr = f.sub(str, -1, -1);									-- get the last character of the output string
				-- str = str .. "<HERE(enchr=" .. end_chr .. ")"				-- debug stuff?
				if end_chr == duplicate_char then								-- if same as separator
					str = f.sub(str, 1, -2);									-- remove it
				--elseif end_chr == "—" and utilities.is_set(dstu_sepc) then	
					--str = f.sub(str, 1, -dstu_sepc:len());
				elseif end_chr == "'" then										-- if it might be wiki-markup
					if f.sub(str, -3, -1) == duplicate_char .. "''" then		-- if last three chars of str are sepc'' 
						str = f.sub(str, 1, -4) .. "''";						-- remove them and add back ''
					elseif  f.sub(str, -5, -1) == duplicate_char .. "]]''" then	-- if last five chars of str are sepc]]'' 
						trim = true;											-- why? why do this and next differently from previous?
					elseif f.sub(str, -4, -1) == duplicate_char .. "]''" then	-- if last four chars of str are sepc]'' 
						trim = true;											-- same question
					end
				elseif end_chr == "]" then										-- if it might be wiki-markup
					if f.sub(str, -3, -1) == duplicate_char .. "]]" then		-- if last three chars of str are sepc]] wikilink 
						trim = true;
					elseif f.sub(str, -3, -1) == duplicate_char .. '"]' then	-- if last three chars of str are sepc"] quoted external link 
						trim = true;
					elseif  f.sub(str, -2, -1) == duplicate_char .. "]" then	-- if last two chars of str are sepc] external link
						trim = true;
					elseif f.sub(str, -4, -1) == duplicate_char .. "'']" then	-- normal case when |url=something & |title=Title.
						trim = true;
					end
				elseif end_chr == " " then										-- if last char of output string is a space
					if f.sub(str, -2, -1) == duplicate_char .. " " then			-- if last two chars of str are <sepc><space>
						str = f.sub(str, 1, -3);								-- remove them both
                    --elseif f.sub(str, -2, -1) == "—" .. " " and utilities.is_set(dstu_sepc) then
                        --str = f.sub(str, 1, -dstu_sepc:len()-1);      
					end
				end

				if trim then
					if value ~= comp then 										-- value does not equal comp when value contains HTML markup
						local dup2 = duplicate_char;
						if f.match(dup2, "%A" ) then dup2 = "%" .. dup2; end	-- if duplicate_char not a letter then escape it
						
						value = f.gsub(value, "(%b<>)" .. dup2, "%1", 1 )		-- remove duplicate_char if it follows HTML markup
					else
						value = f.sub(value, 2, -1 );							-- remove duplicate_char when it is first character
					end
				end
			end
			str = str .. value; 												-- add it to the output string
		end
	end
	return str;
end
			
	
--[[
Return the year portion of a date string, if possible.  
Returns empty string if the argument can not be interpreted
as a year.
]]
local function select_year( str )
    -- Is the input a simple number?
    local num = tonumber( str ); 
    if num ~= nil and num > 0 and num < 2100 and num == math.floor(num) then
        return str;
    else
        -- Use formatDate to interpret more complicated formats
        local lang = mw.getContentLanguage();
        local good, result;
        good, result = pcall( lang.formatDate, lang, 'Y', str )
        if good then 
            return result;
        else
            -- Can't make sense of this input, return blank.
            return "";
        end
    end
end

--[[--------------------------< I S _ S U F F I X >-----------------------------

returns true if suffix is properly formed Jr, Sr, or ordinal in the range 1–9.
Puncutation not allowed.

]]

local function is_suffix (suffix)
	if utilities.in_array (suffix, {'Jr', 'Sr', 'Jnr', 'Snr', '1st', '2nd', '3rd'}) or suffix:match ('^%dth$') then
		return true;
	end
	return false;
end

--[[--------------------< I S _ G O O D _ V A N C _ N A M E >-------------------

For Vancouver style, author/editor names are supposed to be rendered in Latin
(read ASCII) characters.  When a name uses characters that contain diacritical
marks, those characters are to be converted to the corresponding Latin
character. When a name is written using a non-Latin alphabet or logogram, that
name is to be transliterated into Latin characters. The module doesn't do this
so editors may/must.

This test allows |first= and |last= names to contain any of the letters defined
in the four Unicode Latin character sets
	[http://www.unicode.org/charts/PDF/U0000.pdf C0 Controls and Basic Latin] 0041–005A, 0061–007A
	[http://www.unicode.org/charts/PDF/U0080.pdf C1 Controls and Latin-1 Supplement] 00C0–00D6, 00D8–00F6, 00F8–00FF
	[http://www.unicode.org/charts/PDF/U0100.pdf Latin Extended-A] 0100–017F
	[http://www.unicode.org/charts/PDF/U0180.pdf Latin Extended-B] 0180–01BF, 01C4–024F

|lastn= also allowed to contain hyphens, spaces, and apostrophes.
	(http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35029/)
|firstn= also allowed to contain hyphens, spaces, apostrophes, and periods

This original test:
	if nil == mw.ustring.find (last, "^[A-Za-zÀ-ÖØ-öø-ƿDŽ-ɏ%-%s%']*$")
	or nil == mw.ustring.find (first, "^[A-Za-zÀ-ÖØ-öø-ƿDŽ-ɏ%-%s%'%.]+[2-6%a]*$") then
was written outside of the code editor and pasted here because the code editor
gets confused between character insertion point and cursor position. The test has
been rewritten to use decimal character escape sequence for the individual bytes
of the Unicode characters so that it is not necessary to use an external editor
to maintain this code.

	\195\128-\195\150 – À-Ö (U+00C0–U+00D6 – C0 controls)
	\195\152-\195\182 – Ø-ö (U+00D8-U+00F6 – C0 controls)
	\195\184-\198\191 – ø-ƿ (U+00F8-U+01BF – C0 controls, Latin extended A & B)
	\199\132-\201\143 – DŽ-ɏ (U+01C4-U+024F – Latin extended B)

]]

local function is_good_vanc_name (last, first, suffix, position)
	if not suffix then
		if first:find ('[,%s]') then											-- when there is a space or comma, might be first name/initials + generational suffix
			first = first:match ('(.-)[,%s]+');									-- get name/initials
			suffix = first:match ('[,%s]+(.+)$');								-- get generational suffix
		end
	end
	if utilities.is_set (suffix) then
		if not is_suffix (suffix) then
			add_vanc_error (cfg.err_msg_supl.suffix, position);
			return false;														-- not a name with an appropriate suffix
		end
	end
	if nil == mw.ustring.find (last, "^[A-Za-z\195\128-\195\150\195\152-\195\182\195\184-\198\191\199\132-\201\143\225\184\128-\225\187\191%-%s%']*$") or
		nil == mw.ustring.find (first, "^[A-Za-z\195\128-\195\150\195\152-\195\182\195\184-\198\191\199\132-\201\143\225\184\128-\225\187\191%-%s%'%.]*$") then
			add_vanc_error (cfg.err_msg_supl['non-Latin char'], position);
			return false;														-- not a string of Latin characters; Vancouver requires Romanization
	end;
	return true;
end

--[[--------------------------< R E D U C E _ T O _ I N I T I A L S >------------------------------------------

Attempts to convert names to initials in support of |name-list-style=vanc.  

Names in |firstn= may be separated by spaces or hyphens, or for initials, a period.
See http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35062/.

Vancouver style requires family rank designations (Jr, II, III, etc.) to be rendered
as Jr, 2nd, 3rd, etc.  See http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35085/.
This code only accepts and understands generational suffix in the Vancouver format
because Roman numerals look like, and can be mistaken for, initials.

This function uses ustring functions because firstname initials may be any of the
Unicode Latin characters accepted by is_good_vanc_name ().

]]

local function reduce_to_initials (first, position)
	if first:find (',', 1, true) then
		return first;															-- commas not allowed; abandon
	end

	local name, suffix = mw.ustring.match (first, "^(%u+) ([%dJS][%drndth]+)$");

	if not name then															-- if not initials and a suffix
		name = mw.ustring.match (first, "^(%u+)$");								-- is it just initials?
	end

	if name then																-- if first is initials with or without suffix
		if 3 > mw.ustring.len (name) then										-- if one or two initials
			if suffix then														-- if there is a suffix
				if is_suffix (suffix) then										-- is it legitimate?
					return first;												-- one or two initials and a valid suffix so nothing to do
				else
					add_vanc_error (cfg.err_msg_supl.suffix, position);			-- one or two initials with invalid suffix so error message
					return first;												-- and return first unmolested
				end
			else
				return first;													-- one or two initials without suffix; nothing to do
			end
		end
	end																			-- if here then name has 3 or more uppercase letters so treat them as a word

	local initials_t, names_t = {}, {};											-- tables to hold name parts and initials
	local i = 1;																-- counter for number of initials

	names_t = mw.text.split (first, '[%s%-]+');									-- split into a sequence of names and possible suffix

	while names_t[i] do															-- loop through the sequence
		if 1 < i and names_t[i]:match ('[%dJS][%drndth]+%.?$') then				-- if not the first name, and looks like a suffix (may have trailing dot)
			names_t[i] = names_t[i]:gsub ('%.', '');							-- remove terminal dot if present
			if is_suffix (names_t[i]) then										-- if a legitimate suffix
				table.insert (initials_t, ' ' .. names_t[i]);					-- add a separator space, insert at end of initials sequence
				break;															-- and done because suffix must fall at the end of a name
			end																	-- no error message if not a suffix; possibly because of Romanization
		end
		if 3 > i then
			table.insert (initials_t, mw.ustring.sub (names_t[i], 1, 1));		-- insert the initial at end of initials sequence
		end
		i = i + 1;																-- bump the counter
	end
			
	return table.concat (initials_t);											-- Vancouver format does not include spaces.
end

--[[--------------------------< D S T U _ R E D U C E _ T O _ I N I T I A L S >------------------------------------------

Attempts to convert names to initials in support of |mode=dstu.  

This function uses ustring functions because firstname initials may be any of the
Unicode characters.

]]

local function dstu_reduce_to_initials(first, position)
	local name, patronym = mw.ustring.match(first, "^(%u?%l?)%. (%u?%l?)%.$");
	
	if not name then															-- if not name or patronym
		name = mw.ustring.match(first, "^(%u?%l?)%.$");								-- is it just initials?
	end
	
	if name then																-- if first is initials with or without patronym
		if 3 > mw.ustring.len (name) then										-- if one or two initials
			if patronym then
				if 3 > mw.ustring.len (patronym) then
					return first;
				end
			else
				return first;
			end
		end
	end
	
	local initials, names = {}, {};												-- tables to hold name parts and initials
	local i = 1;																-- counter for number of initials

	names = mw.text.split (first, '[%s,]+');									-- split into a table of names and possible patronym
	
	while names[i] do
		if 3 > i then
			local sep;
			if i%2==0 then
				sep = '.';
			else
				sep = '. '
			end
			table.insert (initials, mw.ustring.sub(names[i], 1, 1) .. sep);			-- insert the initial at end of initials table
		end	
		i = i + 1;																-- bump the counter
	end
	
	return table.concat(initials)												
end

-- Formats a list of people (e.g. authors / editors) 
local function list_people(control, people, etal, is_dstu)
    local sep;
    local namesep;
    local format = control.format;
    local maximum = control.maximum;
    local lastauthoramp = control.lastauthoramp;
    local name_list = {};

    if 'vanc' == format or is_dstu then													-- Vancouver/DSTU2006-like name styling?
		sep = cfg.presentation['sep_nl_vanc_dstu'];										-- name-list separator between names is a comma
		namesep = cfg.presentation['sep_name_vanc_dstu'];								-- last/first separator is a space
    elseif utilities.is_set(control.sep) and utilities.is_set(control.namesep) then --перевірка чи використовується стара реалізація цієї функції
        sep = control.sep;                                                      	--присвоєння роздільника між іменами
        namesep = control.namesep;                                              	--присвоєння роздільника між прізвищем і ім'ям                                              
	else
		sep = cfg.presentation['sep_nl'];											-- name-list separator between names is a semicolon
		namesep = cfg.presentation['sep_name'];										-- last/first separator is <comma><space>
	end
    
    if sep:sub(-1,-1) ~= " " then sep = sep .. " " end
    if utilities.is_set (maximum) and maximum < 1 then return "", 0; end        	-- returned 0 is for EditorCount; not used for other names
    
    for i,person in ipairs(people) do
        if utilities.is_set(person.last) then
            local mask = person.mask
            local one
            local sep_one = sep;

            if utilities.is_set (maximum) and i > maximum then
                etal = true;
                break;
            end

            if (mask ~= nil) then
                local n = tonumber(mask)										-- convert to a number if it can be converted; nil else
                if (n ~= nil) then
                    one = string.rep("&mdash;",n)                               -- make a string of (n > 0) mdashes, nil else, to replace name
                else
                    one = mask;													-- replace name with mask text (must include name-list separator)
                    sep_one = " ";												-- modify name-list separator
                end
            else
                one = person.last												-- get surname
                local first = person.first										-- get given name
                if utilities.is_set(first) then 
                    if ( "vanc" == format ) then
                        one = one:gsub ('%.', '');								-- remove periods from surnames (http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35029/) 
                        if not person.corporate and is_good_vanc_name (one, first, nil, i) then		-- and name is all Latin characters; corporate authors not tested
							first = reduce_to_initials (first, i);				-- attempt to convert first name(s) to initials
						end
                    end
                    if is_dstu then
                    	local temp_name, accept = utilities.has_accept_as_written(first);
                    	if accept then
                    		first = temp_name;
                    	else	
                    		first = dstu_reduce_to_initials (first, i);
                    	end	
                    end    
                    one = one .. namesep .. first; 
                end
                if utilities.is_set(person.link) then 
                    one = "[[" .. person.link .. "|" .. one .. "]]"; 				-- link author/editor
                end
            end

            table.insert( name_list, one )
            table.insert( name_list, sep_one )
        end
    end

    local count = #name_list / 2;											-- (number of names + number of separators) divided by 2
    if count > 0 then 
        if count > 1 and not etal then
        	if utilities.is_set(lastauthoramp) or 'amp' == format then
            	name_list[#name_list-2] = " & ";								-- replace last separator with ampersand text
        	elseif 'and' == format then
            	name_list[#name_list-2] = cfg.presentation.sep_nl_and;			-- replace last separator with 'and' text
        	end
        end
        name_list[#name_list] = nil; 
    end
    
    local result = table.concat(name_list)									-- construct list
    if etal and utilities.is_set (result) then							    -- etal may be set by |display-authors=etal but we might not have a last-first list  
        result = result .. " " .. cfg.messages['et al'];					-- we've got a last-first list and etal so add et al.
    end
    
    return result, count
end

-- Generates a CITEREF anchor ID.
local function anchor_id( options )
    return "CITEREF" .. table.concat( options );
end

--[[--------------------------< C I T E _ C L A S S _A T T R I B U T E _M A K E >------------------------------

construct <cite> tag class attribute for this citation.

<cite_class> – config.CitationClass from calling template
<mode> – value from |mode= parameter

]]

local function cite_class_attribute_make (cite_class, mode)
	local class_t = {};
	table.insert (class_t, 'citation');											-- required for blue highlight
	if 'citation' ~= cite_class then
		table.insert (class_t, cite_class);										-- identify this template for user css
		table.insert (class_t, utilities.is_set (mode) and mode or 'cs1');		-- identify the citation style for user css or javascript
	else
		table.insert (class_t, utilities.is_set (mode) and mode or 'cs2');		-- identify the citation style for user css or javascript
	end
	for _, prop_key in ipairs (z.prop_keys_t) do
		table.insert (class_t, prop_key);										-- identify various properties for user css or javascript
	end

	return table.concat (class_t, ' ');											-- make a big string and done
end

--[[---------------------< N A M E _ H A S _ E T A L >--------------------------

Evaluates the content of name parameters (author, editor, etc.) for variations on
the theme of et al.  If found, the et al. is removed, a flag is set to true and
the function returns the modified name and the flag.

This function never sets the flag to false but returns its previous state because
it may have been set by previous passes through this function or by the associated
|display-<names>=etal parameter

]]

local function name_has_etal (name, etal, nocat, param)

	if utilities.is_set (name) then												-- name can be nil in which case just return
		local patterns = cfg.et_al_patterns; 									-- get patterns from configuration
		
		for _, pattern in ipairs (patterns) do									-- loop through all of the patterns
			if  mw.ustring.match(name, pattern) then										-- if this 'et al' pattern is found in name
				name = mw.ustring.gsub (name, pattern, '');									-- remove the offending text
				etal = true;													-- set flag (may have been set previously here or by |display-<names>=etal)
				if not nocat then												-- no categorization for |vauthors=
					utilities.set_message ('err_etal', {param});				-- and set an error if not added
				end
			end
		end
	end

	return name, etal;
end

--[[----------------------< E X T R A C T _ N A M E S >-------------------------

Gets name list from the input arguments

Searches through args in sequential order to find |lastn= and |firstn= parameters
(or their aliases), and their matching link and mask parameters. Stops searching
when both |lastn= and |firstn= are not found in args after two sequential attempts:
found |last1=, |last2=, and |last3= but doesn't find |last4= and |last5= then the
search is done.

This function emits an error message when there is a |firstn= without a matching
|lastn=.  When there are 'holes' in the list of last names, |last1= and |last3=
are present but |last2= is missing, an error message is emitted. |lastn= is not
required to have a matching |firstn=.

When an author or editor parameter contains some form of 'et al.', the 'et al.'
is stripped from the parameter and a flag (etal) returned that will cause list_people()
to add the static 'et al.' text from Module:Citation/CS1/Configuration.  This keeps
'et al.' out of the template's metadata.  When this occurs, an error is emitted.

]]
local function extract_names(args, list_name)
    local names = {};															-- table of names
	local last;																	-- individual name components
	local first;
	local link;
	local mask;
    local i = 1;
    local n = 1;																-- output table indexer
	local count = 0;															-- used to count the number of times we haven't found a |last= (or alias for authors, |editor-last or alias for editors)
	local etal = false;															-- return value set to true when we find some form of et al. in an author parameter
	
    local last_alias, first_alias, link_alias;	
    while true do
        last, last_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'err_redundant_parameters', i );		-- search through args for name components beginning at 1
		first, first_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'err_redundant_parameters', i );
		link, link_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-Link'], 'err_redundant_parameters', i );
		mask = utilities.select_one ( args, cfg.aliases[list_name .. '-Mask'], 'err_redundant_parameters', i );

        last, etal = name_has_etal (last, etal, false, last_alias);				-- find and remove variations on et al.
		first, etal = name_has_etal (first, etal, false, first_alias);			-- find and remove variations on et al.

        if first and not last then												-- if there is a firstn without a matching lastn
			local alias = first_alias:find ('given', 1, true) and 'given' or 'first';	-- get first or given form of the alias
			utilities.set_message ('err_first_missing_last', {
				first_alias,													-- param name of alias missing its mate
				first_alias:gsub (alias, {['first'] = 'last', ['given'] = 'surname'}),	-- make param name appropriate to the alias form
				});																-- add this error message
		elseif not first and not last then										-- if both firstn and lastn aren't found, are we done?
			count = count + 1;													-- number of times we haven't found last and first
			if 2 <= count then													-- two missing names and we give up
				break;															-- normal exit or there is a two-name hole in the list; can't tell which
			end
		else
            local result;
            link = link_title_ok (link, link_alias, last, last_alias);			-- check for improper wiki-markup

			if first then
				link = link_title_ok (link, link_alias, first, first_alias);	-- check for improper wiki-markup
			end

            names[n] = {last = last, first = first, link = link, mask = mask, corporate = false};	-- add this name to our names list (corporate for |vauthors= only)
			n = n + 1;															-- point to next location in the names table
			if 1 == count then													-- if the previous name was missing
				utilities.set_message ('err_missing_name', {list_name:match ("(%w+)List"):ulower(), i - 1});	-- add this error message
			end
			count = 0;															-- reset the counter, we're looking for two consecutive missing names
        end
        i = i + 1;
    end

    return names, etal;
end

--[[-----------------------< S E T _ C S _ S T Y L E >--------------------------

Gets the default CS style configuration for the given mode.
Returns default separator and either postscript as passed in or the default.
In CS1, the default postscript and separator are '.'.
In CS2, the default postscript is the empty string and the default separator is ','.

]]

local function set_cs_style (postscript, mode)
	if utilities.is_set(postscript) then
		-- emit a maintenance message if user postscript is the default cs1 postscript
		-- we catch the opposite case for cs2 in set_style
		if mode == 'cs1' and postscript == cfg.presentation['ps_' .. mode] then
			utilities.set_message ('maint_postscript');
		end
	else
		postscript = cfg.presentation['ps_' .. mode];
	end
	return cfg.presentation['sep_' .. mode], postscript;
end


--[[--------------------------< S E T _ S T Y L E >-----------------------------

Sets the separator and postscript styles. Checks the |mode= first and the
#invoke CitationClass second. Removes the postscript if postscript == none.

]]

local function set_style (mode, postscript, cite_class)
	local sep;
	if 'cs2' == mode then
		sep, postscript = set_cs_style (postscript, 'cs2');
	elseif 'cs1' == mode then
		sep, postscript = set_cs_style (postscript, 'cs1');
	elseif 'dstu2006' == mode then
		sep, postscript = set_cs_style (postscript, 'dstu2006');		
	elseif 'citation' == cite_class	then
		sep, postscript = set_cs_style (postscript, 'cs2');
	else
		sep, postscript = set_cs_style (postscript, 'cs1');
	end

	if cfg.keywords_xlate[postscript:ulower()] == 'none' then
		-- emit a maintenance message if user postscript is the default cs2 postscript
		-- we catch the opposite case for cs1 in set_cs_style
		if 'cs2' == mode or ('cs1' ~= mode and 'citation' == cite_class) then	-- {{citation |title=Title |mode=cs1 |postscript=none}} should not emit maint message
			utilities.set_message ('maint_postscript');
		end
		postscript = '';
	end
	
	return sep, postscript
end

--[=[-------------------------< I S _ P D F >-----------------------------------

Determines if a URL has the file extension that is one of the PDF file extensions
used by [[MediaWiki:Common.css]] when applying the PDF icon to external links.

returns true if file extension is one of the recognized extensions, else false

]=]

local function is_pdf (url)
	return url:match ('%.pdf$') or url:match ('%.PDF$') or
		url:match ('%.pdf[%?#]') or url:match ('%.PDF[%?#]') or
		url:match ('%.PDF&#035') or url:match ('%.pdf&#035');
end


--[[--------------------------< S T Y L E _ F O R M A T >-----------------------

Applies CSS style to |format=, |chapter-format=, etc.  Also emits an error message
if the format parameter does not have a matching URL parameter.  If the format parameter
is not set and the URL contains a file extension that is recognized as a PDF document
by MediaWiki's commons.css, this code will set the format parameter to (PDF) with
the appropriate styling.

]]

local function style_format (format, url, fmt_param, url_param)
	if utilities.is_set (format) then
		format = utilities.wrap_style ('format', format);						-- add leading space, parentheses, resize
		if not utilities.is_set (url) then
			utilities.set_message ('err_format_missing_url', {fmt_param, url_param});	-- add an error message
		end
	elseif is_pdf (url) then													-- format is not set so if URL is a PDF file then
		format = utilities.wrap_style ('format', 'PDF');						-- set format to PDF
	else
		format = '';															-- empty string for concatenation
	end
	return format;
end

--[[---------------------< G E T _ D I S P L A Y _ N A M E S >------------------

Returns a number that defines the number of names displayed for author and editor
name lists and a Boolean flag to indicate when et al. should be appended to the name list.

When the value assigned to |display-xxxxors= is a number greater than or equal to zero,
return the number and the previous state of the 'etal' flag (false by default
but may have been set to true if the name list contains some variant of the text 'et al.').

When the value assigned to |display-xxxxors= is the keyword 'etal', return a number
that is one greater than the number of authors in the list and set the 'etal' flag true.
This will cause the list_people() to display all of the names in the name list followed by 'et al.'

In all other cases, returns nil and the previous state of the 'etal' flag.

inputs:
	max: A['DisplayAuthors'] or A['DisplayEditors'], etc; a number or some flavor of etal
	count: #a or #e
	list_name: 'authors' or 'editors'
	etal: author_etal or editor_etal

This function sets an error message when |display-xxxxors= value greater than or equal to number of names but
not when <max> comes from {{cs1 config}} global settings.  When using global settings, <param> is set to the
keyword 'cs1 config' which is used to supress the normal error.  Error is suppressed because it is to be expected
that some citations in an article will have the same or fewer names that the limit specified in {{cs1 config}}.

]]

local function get_display_names (max, count, list_name, etal, param)
	if utilities.is_set (max) then
		if 'etal' == max:ulower():gsub("[ '%.]", '') then						-- the :gsub() portion makes 'etal' from a variety of 'et al.' spellings and stylings
			max = count + 1;													-- number of authors + 1 so display all author name plus et al.
			etal = true;														-- overrides value set by extract_names()
		elseif max:match ('^%d+$') then											-- if is a string of numbers
			max = tonumber (max);												-- make it a number
			if (max >= count) and ('cs1 config' ~= param) then					-- error when local |display-xxxxors= value greater than or equal to number of names; not an error when using global setting
				utilities.set_message ('err_disp_name', {param, max});					-- add error message
				max = nil;
			end
		else																	-- not a valid keyword or number
			utilities.set_message ('err_disp_name', {param, max});						-- add error message
			max = nil;															-- unset; as if |display-xxxxors= had not been set
		end
	end
	
	return max, etal;
end

--[[----------< E X T R A _ T E X T _ I N _ P A G E _ C H E C K >---------------

Adds error if |page=, |pages=, |quote-page=, |quote-pages= has what appears to be
some form of p. or pp. abbreviation in the first characters of the parameter content.

check page for extraneous p, p., pp, pp., pg, pg. at start of parameter value:
	good pattern: '^P[^%.P%l]' matches when page begins PX or P# but not Px
		      where x and X are letters and # is a digit
	bad pattern:  '^[Pp][PpGg]' matches when page begins pp, pP, Pp, PP, pg, pG, Pg, PG

]]

local function extra_text_in_page_check (val, name)
	if not val:match (cfg.vol_iss_pg_patterns.good_ppattern) then
		for _, pattern in ipairs (cfg.vol_iss_pg_patterns.bad_ppatterns) do		-- spin through the selected sequence table of patterns
			if val:match (pattern) then											-- when a match, error so
				utilities.set_message ('err_extra_text_pages', name);	 		-- add error message
				return;															-- and done
			end
		end
	end		
end

--[=[-------------------------< G E T _ V _ N A M E _ T A B L E >----------------------------------------------

split apart a |vauthors= or |veditors= parameter.  This function allows for corporate names, wrapped in doubled
parentheses to also have commas; in the old version of the code, the doubled parentheses were included in the
rendered citation and in the metadata.  Individual author names may be wikilinked

	|vauthors=Jones AB, [[E. B. White|White EB]], ((Black, Brown, and Co.))

]=]

local function get_v_name_table (vparam, output_table, output_link_table)
	local name_table = mw.text.split(vparam, "%s*,%s*");						-- names are separated by commas
	local wl_type, label, link;													-- wl_type not used here; just a placeholder
	
	local i = 1;
	
	while name_table[i] do
		if name_table[i]:match ('^%(%(.*[^%)][^%)]$') then						-- first segment of corporate with one or more commas; this segment has the opening doubled parentheses
			local name = name_table[i];
			i = i + 1;															-- bump indexer to next segment
			while name_table[i] do
				name = name .. ', ' .. name_table[i];							-- concatenate with previous segments
				if name_table[i]:match ('^.*%)%)$') then						-- if this table member has the closing doubled parentheses
					break;														-- and done reassembling so
				end
				i = i + 1;														-- bump indexer
			end
			table.insert (output_table, name);									-- and add corporate name to the output table
			table.insert (output_link_table, '');								-- no wikilink
		else
			wl_type, label, link = utilities.is_wikilink (name_table[i]);		-- wl_type is: 0, no wl (text in label variable); 1, [[D]]; 2, [[L|D]]
			table.insert (output_table, label);									-- add this name
			if 1 == wl_type then
				table.insert (output_link_table, label);						-- simple wikilink [[D]]
			else
				table.insert (output_link_table, link);							-- no wikilink or [[L|D]]; add this link if there is one, else empty string
			end
		end
		i = i + 1;
	end	
	return output_table;
end


--[[--------------------------< P A R S E _ V A U T H O R S _ V E D I T O R S >--------------------------------

This function extracts author / editor names from |vauthors= or |veditors= and finds matching |xxxxor-maskn= and
|xxxxor-linkn= in args.  It then returns a table of assembled names just as extract_names() does.

Author / editor names in |vauthors= or |veditors= must be in Vancouver system style. Corporate or institutional names
may sometimes be required and because such names will often fail the is_good_vanc_name() and other format compliance
tests, are wrapped in doubled parentheses ((corporate name)) to suppress the format tests.

Supports generational suffixes Jr, 2nd, 3rd, 4th–6th.

This function sets the Vancouver error when a required comma is missing and when there is a space between an author's initials.

]]

local function parse_vauthors_veditors (args, vparam, list_name)
	local names = {};															-- table of names assembled from |vauthors=, |author-maskn=, |author-linkn=
	local v_name_table = {};
	local v_link_table = {};													-- when name is wikilinked, targets go in this table
	local etal = false;															-- return value set to true when we find some form of et al. vauthors parameter
	local last, first, link, mask, suffix;
	local corporate = false;

	vparam, etal = name_has_etal (vparam, etal, true);							-- find and remove variations on et al. do not categorize (do it here because et al. might have a period)
	v_name_table = get_v_name_table (vparam, v_name_table, v_link_table);		-- names are separated by commas

	for i, v_name in ipairs(v_name_table) do
		first = '';																-- set to empty string for concatenation and because it may have been set for previous author/editor
		local accept_name;
		v_name, accept_name = utilities.has_accept_as_written (v_name);			-- remove accept-this-as-written markup when it wraps all of <v_name>

		if accept_name then
			last = v_name;
			corporate = true;													-- flag used in list_people()
		elseif string.find(v_name, "%s") then
			if v_name:find('[;%.]') then										-- look for commonly occurring punctuation characters; 
				add_vanc_error (cfg.err_msg_supl.punctuation, i);
			end
			local lastfirstTable = {}
			lastfirstTable = mw.text.split(v_name, "%s+")
			first = table.remove(lastfirstTable);								-- removes and returns value of last element in table which should be initials or generational suffix

			if not mw.ustring.match (first, '^%u+$') then						-- mw.ustring here so that later we will catch non-Latin characters
				suffix = first;													-- not initials so assume that whatever we got is a generational suffix
				first = table.remove(lastfirstTable);							-- get what should be the initials from the table
			end
			last = table.concat(lastfirstTable, ' ')							-- returns a string that is the concatenation of all other names that are not initials and generational suffix
			if not utilities.is_set (last) then
				first = '';														-- unset
				last = v_name;													-- last empty because something wrong with first
				add_vanc_error (cfg.err_msg_supl.name, i);
			end
			if mw.ustring.match (last, '%a+%s+%u+%s+%a+') then
				add_vanc_error (cfg.err_msg_supl['missing comma'], i);			-- matches last II last; the case when a comma is missing
			end
			if mw.ustring.match (v_name, ' %u %u$') then						-- this test is in the wrong place TODO: move or replace with a more appropriate test
				add_vanc_error (cfg.err_msg_supl.initials, i);					-- matches a space between two initials
			end
		else
			last = v_name;														-- last name or single corporate name?  Doesn't support multiword corporate names? do we need this?
		end
		
		if utilities.is_set (first) then
			if not mw.ustring.match (first, "^%u?%u$") then						-- first shall contain one or two upper-case letters, nothing else
				add_vanc_error (cfg.err_msg_supl.initials, i);					-- too many initials; mixed case initials (which may be ok Romanization); hyphenated initials
			end
			is_good_vanc_name (last, first, suffix, i);							-- check first and last before restoring the suffix which may have a non-Latin digit
			if utilities.is_set (suffix) then
				first = first .. ' ' .. suffix;									-- if there was a suffix concatenate with the initials
				suffix = '';													-- unset so we don't add this suffix to all subsequent names
			end
		else
			if not corporate then
				is_good_vanc_name (last, '', nil, i);
			end
		end

		link = utilities.select_one ( args, cfg.aliases[list_name .. '-Link'], 'err_redundant_parameters', i ) or v_link_table[i];
		mask = utilities.select_one ( args, cfg.aliases[list_name .. '-Mask'], 'err_redundant_parameters', i );
		names[i] = {last = last, first = first, link = link, mask = mask, corporate = corporate};		-- add this assembled name to our names list
	end
	return names, etal;															-- all done, return our list of names
end


--[[--------------------------< S E L E C T _ A U T H O R _ E D I T O R _ S O U R C E >------------------------

Select one of |authors=, |authorn= / |lastn / firstn=, or |vauthors= as the source of the author name list or
select one of |editorn= / editor-lastn= / |editor-firstn= or |veditors= as the source of the editor name list.

Only one of these appropriate three will be used.  The hierarchy is: |authorn= (and aliases) highest and |authors= lowest;
|editorn= (and aliases) highest and |veditors= lowest (support for |editors= withdrawn)

When looking for |authorn= / |editorn= parameters, test |xxxxor1= and |xxxxor2= (and all of their aliases); stops after the second
test which mimicks the test used in extract_names() when looking for a hole in the author name list.  There may be a better
way to do this, I just haven't discovered what that way is.

Emits an error message when more than one xxxxor name source is provided.

In this function, vxxxxors = vauthors or veditors; xxxxors = authors as appropriate.

]]

local function select_author_editor_source (vxxxxors, xxxxors, args, list_name)
	local lastfirst = false;
	if utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'none', 1 ) or		-- do this twice in case we have a |first1= without a |last1=; this ...
		utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'none', 1 ) or		-- ... also catches the case where |first= is used with |vauthors=
		utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'none', 2 ) or
		utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'none', 2 ) then
			lastfirst = true;
	end

	if (utilities.is_set (vxxxxors) and true == lastfirst) or					-- these are the three error conditions
		(utilities.is_set (vxxxxors) and utilities.is_set (xxxxors)) or
		(true == lastfirst and utilities.is_set (xxxxors)) then
			local err_name;
			if 'AuthorList' == list_name then									-- figure out which name should be used in error message
				err_name = 'author';
			else
				err_name = 'editor';
			end
			utilities.set_message ('err_redundant_parameters', 'параметр' .. err_name .. '-name-list');	-- add error message
	end

	if true == lastfirst then return 1 end;										-- return a number indicating which author name source to use
	if utilities.is_set (vxxxxors) then return 2 end;
	if utilities.is_set (xxxxors) then return 3 end;
	return 1;																	-- no authors so return 1; this allows missing author name test to run in case there is a first without last 
end

--[[--------------------------< I S _ V A L I D _ P A R A M E T E R _ V A L U E >------------------------------

This function is used to validate a parameter's assigned value for those parameters that have only a limited number
of allowable values (yes, y, true, live, dead, etc.).  When the parameter value has not been assigned a value (missing
or empty in the source template) the function returns the value specified by ret_val.  If the parameter value is one
of the list of allowed values returns the translated value; else, emits an error message and returns the value
specified by ret_val.

TODO: explain <invert>

]]

local function is_valid_parameter_value (value, name, possible, ret_val, invert)
	if not utilities.is_set (value) then
		return ret_val;															-- an empty parameter is ok
	end

	if (not invert and utilities.in_array (value, possible)) then				-- normal; <value> is in <possible> table
		return cfg.keywords_xlate[value];										-- return translation of parameter keyword
	elseif invert and not utilities.in_array (value, possible) then				-- invert; <value> is not in <possible> table
		return value;															-- return <value> as it is
	else
		utilities.set_message ('err_invalid_param_val', {name, value});			-- not an allowed value so add error message
		return ret_val;
	end
end

--[[--------------------------< T E R M I N A T E _ N A M E _ L I S T >----------------------------------------

This function terminates a name list (author, contributor, editor) with a separator character (sepc) and a space
when the last character is not a sepc character or when the last three characters are not sepc followed by two
closing square brackets (close of a wikilink).  When either of these is true, the name_list is terminated with a
single space character.

]]

local function terminate_name_list (name_list, sepc)
	if (string.sub (name_list, -3, -1) == sepc .. '. ') then					-- if already properly terminated
		return name_list;														-- just return the name list
	elseif (string.sub (name_list, -1, -1) == sepc) or (string.sub (name_list, -3, -1) == sepc .. ']]') then	-- if last name in list ends with sepc char
		return name_list .. " ";												-- don't add another
	else
		return name_list .. sepc .. ' ';										-- otherwise terminate the name list
	end
end

--[[-------------------------< F O R M A T _ V O L U M E _ I S S U E >-----------------------------------------

returns the concatenation of the formatted volume and issue (or journal article number) parameters as a single
string; or formatted volume or formatted issue, or an empty string if neither are set.

]]
	
local function format_volume_issue (volume, issue, article, cite_class, origin, sepc, lower)
	if not utilities.is_set (volume) and not utilities.is_set (issue) and not utilities.is_set (article) then
		return '';
	end

	-- same condition as in format_pages_sheets()
	local is_journal = 'journal' == cite_class or (utilities.in_array (cite_class, {'citation', 'map', 'interview'}) and 'journal' == origin);

	local is_numeric_vol = volume and (volume:match ('^[MDCLXVI]+$') or volume:match ('^%d+$'));	-- is only uppercase roman numerals or only digits?
	local is_long_vol = volume and (4 < mw.ustring.len(volume));				-- is |volume= value longer than 4 characters?
	
	if volume and (not is_numeric_vol and is_long_vol) then						-- when not all digits or Roman numerals, is |volume= longer than 4 characters?
		utilities.add_prop_cat ('long-vol');									-- yes, add properties cat
	end

	if is_journal then															-- journal-style formatting
		local vol = '';

		if utilities.is_set (volume) then
			if is_numeric_vol then												-- |volume= value all digits or all uppercase Roman numerals?
				vol = utilities.substitute (cfg.presentation['vol-bold'], {sepc, volume});	-- render in bold face
			elseif is_long_vol then												-- not all digits or Roman numerals; longer than 4 characters?
				vol = utilities.substitute (cfg.messages['j-vol'], {sepc, utilities.hyphen_to_dash (volume)});	-- not bold
			else																-- four or fewer characters
				vol = utilities.substitute (cfg.presentation['vol-bold'], {sepc, utilities.hyphen_to_dash (volume)});	-- bold
			end
		end
		vol = vol .. (utilities.is_set (issue) and utilities.substitute (cfg.messages['j-issue'], issue) or '')
		vol = vol .. (utilities.is_set (article) and utilities.substitute (cfg.messages['j-article-num'], article) or '')
		return vol;
	end
	
	if 'podcast' == cite_class and utilities.is_set (issue) then
		return wrap_msg ('issue', {sepc, issue}, lower);
	end
	
	if 'conference' == cite_class and utilities.is_set (article) then			-- |article-number= supported only in journal and conference cites
		if utilities.is_set (volume) and utilities.is_set (article) then		-- both volume and article number
			return wrap_msg ('vol-art', {sepc, utilities.hyphen_to_dash (volume), article}, lower);
		elseif utilities.is_set (article) then									-- article number alone; when volume alone, handled below
			return wrap_msg ('art', {sepc, article}, lower);
		end
	end

	-- all other types of citation
	if utilities.is_set (volume) and utilities.is_set (issue) then
		return wrap_msg ('vol-no', {sepc, utilities.hyphen_to_dash (volume), issue}, lower);
	elseif utilities.is_set (volume) then
		return wrap_msg ('vol', {sepc, utilities.hyphen_to_dash (volume)}, lower);
	else
		return wrap_msg ('issue', {sepc, issue}, lower);
	end
end

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

adds static text to one of |page(s)= or |sheet(s)= values and returns it with all of the others set to empty strings.
The return order is:
	page, pages, sheet, sheets

Singular has priority over plural when both are provided.

]]

local function format_pages_sheets (page, pages, sheet, sheets, cite_class, origin, sepc, nopp, lower, is_dstu)
	local p_prefix, pp_prefix, j_page, j_sheet, j_sheets;
	
	if is_dstu then
		p_prefix = cfg.messages['dstu-p-prefix'];
		pp_prefix = cfg.messages['dstu-pp-prefix'];
		j_page = cfg.messages['dstu-j-page(s)'];
		j_sheet = 'dstu-j-sheet';
		j_sheets = 'dstu-j-sheets';
	else
		p_prefix = cfg.messages['p-prefix'];
		pp_prefix = cfg.messages['pp-prefix'];
		j_page = cfg.messages['j-page(s)'];
		j_sheet = 'j-sheet';
		j_sheets = 'j-sheets';
	end	
	
	if 'map' == cite_class then													-- only cite map supports sheet(s) as in-source locators
		if utilities.is_set (sheet) then
			if 'journal' == origin then
				return '', '', wrap_msg (j_sheet, sheet, lower), '';
			else
				return '', '', wrap_msg ('sheet', {sepc, sheet}, lower), '';
			end
		elseif utilities.is_set (sheets) then
			if 'journal' == origin then
				return '', '', '', wrap_msg (j_sheets, sheets, lower);
			else
				return '', '', '', wrap_msg ('sheets', {sepc, sheets}, lower);
			end
		end
	end

	local is_journal = 'journal' == cite_class or (utilities.in_array (cite_class, {'citation', 'map', 'interview'}) and 'journal' == origin);
	
	if utilities.is_set (page) then
		if is_journal then
			return utilities.substitute (j_page, page), '', '', '';
		elseif not nopp then
			return utilities.substitute (p_prefix, {sepc, page}), '', '', '';
		else
			return utilities.substitute (cfg.messages['nopp'], {sepc, page}), '', '', '';
		end
	elseif utilities.is_set (pages) then
		if is_journal then
			return utilities.substitute (j_page, pages), '', '', '';
		elseif tonumber(pages) ~= nil and not nopp then							-- if pages is only digits, assume a single page number
			return '', utilities.substitute (p_prefix, {sepc, pages}), '', '';
		elseif not nopp then
			return '', utilities.substitute (pp_prefix, {sepc, pages}), '', '';
		else
			return '', utilities.substitute (cfg.messages['nopp'], {sepc, pages}), '', '';
		end
	end
	
	return '', '', '', '';														-- return empty strings
end

--[[--------------------------< I N S O U R C E _ L O C _ G E T >----------------------------------------------

returns one of the in-source locators: page, pages, or at. 

If any of these are interwiki links to Wikisource, returns the label portion of the interwiki-link as plain text
for use in COinS.  This COinS thing is done because here we convert an interwiki-link to an external link and
add an icon span around that; get_coins_pages() doesn't know about the span.  TODO: should it?  

TODO: add support for sheet and sheets?; streamline;

TODO: make it so that this function returns only one of the three as the single in-source (the return value assigned
to a new name)?

]]

local function insource_loc_get (page, page_orig, pages, pages_orig, at)
	local ws_url, ws_label, coins_pages, L;										-- for Wikisource interwiki-links; TODO: this corrupts page metadata (span remains in place after cleanup; fix there?)

	if utilities.is_set (page) then
		if utilities.is_set (pages) or utilities.is_set (at) then
			pages = '';															-- unset the others
			at = '';
		end
		extra_text_in_page_check (page, page_orig);								-- emit error message when |page= value begins with what looks like p., pp., etc.

		ws_url, ws_label, L = wikisource_url_make (page);						-- make ws URL from |page= interwiki link; link portion L becomes tooltip label
		if ws_url then
			page = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in page');	-- space char after label to move icon away from in-source text; TODO: a better way to do this?
			page = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, page});
			coins_pages = ws_label;
		end
	elseif utilities.is_set (pages) then
		if utilities.is_set (at) then
			at = '';															-- unset
		end
		extra_text_in_page_check (pages, pages_orig);							-- emit error message when |page= value begins with what looks like p., pp., etc.

		ws_url, ws_label, L = wikisource_url_make (pages);						-- make ws URL from |pages= interwiki link; link portion L becomes tooltip label
		if ws_url then
			pages = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in pages');	-- space char after label to move icon away from in-source text; TODO: a better way to do this?
			pages = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, pages});
			coins_pages = ws_label;
		end
	elseif utilities.is_set (at) then
		ws_url, ws_label, L = wikisource_url_make (at);							-- make ws URL from |at= interwiki link; link portion L becomes tooltip label
		if ws_url then
			at = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in at');	-- space char after label to move icon away from in-source text; TODO: a better way to do this?
			at = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, at});
			coins_pages = ws_label;
		end
	end
	
	return page, pages, at, coins_pages;
end

--[[--------------------------< I S _ A R C H I V E D _ C O P Y >----------------------------------------------

compares |title= to 'Archived copy' (placeholder added by bots that can't find proper title); if matches, return true; nil else

]]

local function is_archived_copy (title)
	title = mw.ustring.lower(title);											-- switch title to lower case
	if title:find (cfg.special_case_translation.archived_copy.en) then			-- if title is 'Archived copy'
		return true;
	elseif cfg.special_case_translation.archived_copy['local'] then
		if mw.ustring.find (title, cfg.special_case_translation.archived_copy['local']) then	-- mw.ustring() because might not be Latin script
			return true;
		end
	end
end

--[[
This is the main function foing the majority of the citation
formatting.
]]
local function citation0( config, args)
    --[[ 
    Load Input Parameters
    The argment_wrapper facillitates the mapping of multiple
    aliases to single internal variable.
    ]]
    local A = argument_wrapper( args );

    local i 
   -- local PPrefix = A['PPrefix']
  --  local PPPrefix = A['PPPrefix']
  --  if utilities.is_set( A['NoPP'] ) then PPPrefix = "" PPrefix = "" end
    
    -- Pick out the relevant fields from the arguments.  Different citation templates
    -- define different field names for the same underlying things.    
    local Authors = A['Authors'];
    local author_etal;
    local a = {};
    
    local NameListStyle;
    
    NameListStyle = is_valid_parameter_value (A['NameListStyle'], A:ORIGIN('NameListStyle'), cfg.keywords_lists['name-list-style'], '');
    
    local Coauthors = A['Coauthors'];
    
    do																			-- to limit scope of selected
		local selected = select_author_editor_source (A['Vauthors'], A['Authors'], args, 'AuthorList');
		if 1 == selected then
			a, author_etal = extract_names (args, 'AuthorList');				-- fetch author list from |authorn= / |lastn= / |firstn=, |author-linkn=, and |author-maskn=
		elseif 2 == selected then
			NameListStyle = 'vanc';												-- override whatever |name-list-style= might be
			a, author_etal = parse_vauthors_veditors (args, A['Vauthors'], 'AuthorList');	-- fetch author list from |vauthors=, |author-linkn=, and |author-maskn=
		end                                                                   -- 
    end
    
    local Others = A['Others'];
    local Editors = A['Editors'];
    local EditorCount;
    local editor_etal;
    local e = {};
    
    do																			-- to limit scope of selected
		local selected = select_author_editor_source (A['Veditors'], A['Editors'], args, 'EditorList');	-- support for |editors= withdrawn
		if 1 == selected then
			e, editor_etal = extract_names (args, 'EditorList');				-- fetch editor list from |editorn= / |editor-lastn= / |editor-firstn=, |editor-linkn=, and |editor-maskn=
		elseif 2 == selected then
			NameListStyle = 'vanc';												-- override whatever |name-list-style= might be
			e, editor_etal = parse_vauthors_veditors (args, args.veditors, 'EditorList');	-- fetch editor list from |veditors=, |editor-linkn=, and |editor-maskn=
		end
    end

    local Chapter = A['Chapter'];
    local Chapter_origin = A:ORIGIN ('Chapter');
	
	local Title = A['Title'];
    local TitleLink = A['TitleLink'];
    local auto_select = '';	
    
    TitleLink = link_title_ok (TitleLink, A:ORIGIN ('TitleLink'), Title, 'title');	-- check for wiki-markup in |title-link= or wiki-markup in |title= when |title-link= is set
    
    local Section = '';															-- {{cite map}} only; preset to empty string for concatenation if not used
    if 'map' == config.CitationClass and 'section' == Chapter_origin then
		Section = A['Chapter'];													-- get |section= from |chapter= alias list; |chapter= and the other aliases not supported in {{cite map}}
		Chapter = '';															-- unset for now; will be reset later from |map= if present
	end
    
    local Periodical = A['Periodical'];
    local Periodical_origin = A:ORIGIN('Periodical');
	local ScriptPeriodical = A['ScriptPeriodical'];
	local ScriptPeriodical_origin = A:ORIGIN('ScriptPeriodical');
	local TransPeriodical =  A['TransPeriodical'];
	local TransPeriodical_origin =  A:ORIGIN ('TransPeriodical');
    
    if (utilities.in_array (config.CitationClass, {'book', 'encyclopaedia'}) and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical) or utilities.is_set (TransPeriodical))) then
		local param;
		if utilities.is_set (Periodical) then									-- get a parameter name from one of these periodical related meta-parameters
			Periodical = '';													-- unset because not valid {{cite book}} or {{cite encyclopedia}} parameters 
			param = Periodical_origin											-- get parameter name for error messaging
		elseif utilities.is_set (TransPeriodical) then
			TransPeriodical = '';												-- unset because not valid {{cite book}} or {{cite encyclopedia}} parameters 
			param = TransPeriodical_origin;										-- get parameter name for error messaging
		elseif utilities.is_set (ScriptPeriodical) then
			ScriptPeriodical = '';												-- unset because not valid {{cite book}} or {{cite encyclopedia}} parameters 
			param = ScriptPeriodical_origin;									-- get parameter name for error messaging
		end

		if utilities.is_set (param) then										-- if we found one
			utilities.set_message ('err_periodical_ignored', {param});			-- emit an error message
		end
	end
    
    if 'mailinglist' == config.CitationClass then								-- special case for {{cite mailing list}}
		if utilities.is_set (Periodical) and utilities.is_set (A ['MailingList']) then	-- both set emit an error TODO: make a function for this and similar?
			utilities.set_message ('err_redundant_parameters', {utilities.wrap_style ('parameter', Periodical_origin) .. cfg.presentation['sep_list_pair'] .. utilities.wrap_style ('parameter', 'mailinglist')});
		end

		Periodical = A ['MailingList'];											-- error or no, set Periodical to |mailinglist= value because this template is {{cite mailing list}}
		Periodical_origin = A:ORIGIN('MailingList');
    end

	local Volume = A['Volume'];
	local Issue = A['Issue'];
--	local Page, Pages, At, page_type;
	
	local ArticleNumber;

	if utilities.in_array (config.CitationClass, {'journal', 'conference'}) or ('citation' == config.CitationClass and utilities.is_set (Periodical) and 'journal' == Periodical_origin) then
		ArticleNumber = A['ArticleNumber'];
	end
    
    local Page;
	local Pages;
	local At;
--	if not utilities.in_array (config.CitationClass, cfg.templates_not_using_page) then		-- TODO: rewrite to emit ignored parameter error message?
		Page = A['Page'];
		Pages = utilities.hyphen_to_dash (A['Pages']);	
		At = A['At'];
--		QuotePage = A['QuotePage'];                                             -- (поки закоментовано для майбутнього впровадження)
--		QuotePages = utilities.hyphen_to_dash (A['QuotePages']);
--	end
    
    local Edition = A['Edition'];
    local PublicationPlace = A['PublicationPlace']
    local Place = A['Place'];
    
    if not utilities.is_set(PublicationPlace) and utilities.is_set(Place) then
        PublicationPlace = Place;
    end
    
    if PublicationPlace == Place then Place = ''; end
    
    local PublisherName = A['PublisherName'];
    
    local URL = A['URL'];
    local UrlAccess = is_valid_parameter_value (A['UrlAccess'], A:ORIGIN('UrlAccess'), cfg.keywords_lists['url-access'], nil);
    local SubscriptionRequired = A['SubscriptionRequired'];
    
    if utilities.is_set(SubscriptionRequired) then
    	UrlAccess = is_valid_parameter_value ('subscription', A:ORIGIN('SubscriptionRequired'), cfg.keywords_lists['url-access'], nil);
    end
	
	if not utilities.is_set (URL) and utilities.is_set (UrlAccess) then
		UrlAccess = nil;
		utilities.set_message ('err_param_access_requires_param', 'url');
	end
	
	local ChapterURL = A['ChapterURL'];
	local ChapterUrlAccess = is_valid_parameter_value (A['ChapterUrlAccess'], A:ORIGIN('ChapterUrlAccess'), cfg.keywords_lists['url-access'], nil);
	if not utilities.is_set (ChapterURL) and utilities.is_set (ChapterUrlAccess) then
		ChapterUrlAccess = nil;
		utilities.set_message ('err_param_access_requires_param', {A:ORIGIN('ChapterUrlAccess'):gsub ('%-access', '')});
	end
	
	local MapUrlAccess = is_valid_parameter_value (A['MapUrlAccess'], A:ORIGIN('MapUrlAccess'), cfg.keywords_lists['url-access'], nil);
	if not utilities.is_set (A['MapURL']) and utilities.is_set (MapUrlAccess) then
		MapUrlAccess = nil;
		utilities.set_message ('err_param_access_requires_param', {'map-url'});
	end
	
	local this_page = mw.title.getCurrentTitle();  --Also used for COinS
    local no_tracking_cats = is_valid_parameter_value (A['NoTracking'], A:ORIGIN('NoTracking'), cfg.keywords_lists['yes_true_y'], nil);
    
    -- check this page to see if it is in one of the namespaces that cs1 is not supposed to add to the error categories
	if not utilities.is_set (no_tracking_cats) then								-- ignore if we are already not going to categorize this page
		if cfg.uncategorized_namespaces[this_page.namespace] then				-- is this page's namespace id one of the uncategorized namespace ids?
			no_tracking_cats = "true";											-- set no_tracking_cats
		end
		for _, v in ipairs (cfg.uncategorized_subpages) do						-- cycle through page name patterns
			if this_page.text:match (v) then									-- test page name against each pattern
				no_tracking_cats = "true";										-- set no_tracking_cats
				break;															-- bail out if one is found
			end
		end
	end
	   																			-- check for extra |page=, |pages= or |at= parameters. (also sheet and sheets while we're at it)
	utilities.select_one (args, {'page', 'p', 'pp', 'pages', 'at', 'sheet', 'sheets'}, 'err_redundant_parameters');	-- this is a dummy call simply to get the error message and category
    
    local coins_pages;
	
	Page, Pages, At, coins_pages = insource_loc_get (Page, A:ORIGIN('Page'), Pages, A:ORIGIN('Pages'), At);
    
    local NoPP = is_valid_parameter_value (A['NoPP'], A:ORIGIN('NoPP'), cfg.keywords_lists['yes_true_y'], nil);
    
    local URL_origin = A:ORIGIN('URL');											-- get name of parameter that holds URL
    local ChapterURL_origin = A:ORIGIN('ChapterURL');
    local ScriptChapter = A['ScriptChapter'];
    local ScriptChapter_origin = A:ORIGIN ('ScriptChapter');
    local Format = A['Format'];
    local ChapterFormat = A['ChapterFormat'];
    local TransChapter = A['TransChapter'];
    local TransChapter_origin = A:ORIGIN ('TransChapter');
    local ScriptTitle = A['ScriptTitle'];
    local TransTitle = A['TransTitle'];
    
    --[[
	Parameter remapping for cite encyclopedia:
	When the citation has these parameters:
		|encyclopedia= and |title= then map |title= to |article= and |encyclopedia= to |title= for rendering
		|encyclopedia= and |article= then map |encyclopedia= to |title= for rendering

		|trans-title= maps to |trans-chapter= when |title= is re-mapped
		|url= maps to |chapter-url= when |title= is remapped
	
	All other combinations of |encyclopedia=, |title=, and |article= are not modified
	
	]]

	local Encyclopedia = A['Encyclopedia'];										-- used as a flag by this module and by ~/COinS
	local ScriptEncyclopedia = A['ScriptEncyclopedia'];
	local TransEncyclopedia = A['TransEncyclopedia'];

	if utilities.is_set (Encyclopedia) or utilities.is_set (ScriptEncyclopedia) then	-- emit error message when Encyclopedia set but template is other than {{cite encyclopedia}} or {{citation}}
		if 'encyclopaedia' ~= config.CitationClass and 'citation' ~= config.CitationClass then
			if utilities.is_set (Encyclopedia) then
				utilities.set_message ('err_parameter_ignored', {A:ORIGIN ('Encyclopedia')});
			else
				utilities.set_message ('err_parameter_ignored', {A:ORIGIN ('ScriptEncyclopedia')});
			end
			Encyclopedia = nil;													-- unset these because not supported by this template
			ScriptEncyclopedia = nil;
			TransEncyclopedia = nil;
		end
	elseif utilities.is_set (TransEncyclopedia) then
		utilities.set_message ('err_trans_missing_title', {'encyclopedia'});
	end

	if ('encyclopaedia' == config.CitationClass) or ('citation' == config.CitationClass and utilities.is_set (Encyclopedia)) then
		if utilities.is_set (Periodical) and utilities.is_set (Encyclopedia) then	-- when both parameters set emit an error message; {{citation}} only; Periodical not allowed in {{cite encyclopedia}}
			utilities.set_message ('err_periodical_ignored', {Periodical_origin});
		end

		if utilities.is_set (Encyclopedia) or utilities.is_set (ScriptEncyclopedia) then
			Periodical = Encyclopedia;											-- error or no, set Periodical to Encyclopedia for rendering; {{citation}} could (not legitimately) have both; use Encyclopedia
			Periodical_origin = A:ORIGIN ('Encyclopedia');
			ScriptPeriodical = ScriptEncyclopedia;
			ScriptPeriodical_origin = A:ORIGIN ('ScriptEncyclopedia');

			if utilities.is_set (Title) or utilities.is_set (ScriptTitle) then
				if not utilities.is_set (Chapter) then
					Chapter = Title;											-- |encyclopedia= and |title= are set so map |title= params to |article= params for rendering
					ScriptChapter = ScriptTitle;
					ScriptChapter_origin = A:ORIGIN('ScriptTitle')
					TransChapter = TransTitle;
					ChapterURL = URL;
					ChapterURL_origin = URL_origin;
					ChapterUrlAccess = UrlAccess;
					ChapterFormat = Format;

					if not utilities.is_set (ChapterURL) and utilities.is_set (TitleLink) then
						Chapter = utilities.make_wikilink (TitleLink, Chapter);
					end
					Title = Periodical;											-- now map |encyclopedia= params to |title= params for rendering
					ScriptTitle = ScriptPeriodical or '';
					TransTitle = TransEncyclopedia or '';
					Periodical = '';											-- redundant so unset
					ScriptPeriodical = '';
					URL = '';
					Format = '';
					TitleLink = '';
				end
			elseif utilities.is_set (Chapter) or utilities.is_set (ScriptChapter) then	-- |title= not set
				Title = Periodical;												-- |encyclopedia= set and |article= set so map |encyclopedia= to |title= for rendering
				ScriptTitle = ScriptPeriodical or '';
				TransTitle = TransEncyclopedia or '';
				Periodical = '';												-- redundant so unset
				ScriptPeriodical = '';
			end
		end
	end
	
	local ID = A['ID'];
	
	-- Account for the oddity that is {{cite conference}}, before generation of COinS data.
	local ChapterLink -- = A['ChapterLink'];									-- deprecated as a parameter but still used internally by cite episode
	local Conference = A['Conference'];
	local BookTitle = A['BookTitle'];
    local TransTitle_origin = A:ORIGIN ('TransTitle');
	if 'conference' == config.CitationClass then
		if utilities.is_set (BookTitle) then
			Chapter = Title;
			Chapter_origin = 'title';
	--		ChapterLink = TitleLink;											-- |chapter-link= is deprecated
			ChapterURL = URL;
			ChapterUrlAccess = UrlAccess;
			ChapterURL_origin = URL_origin;
			URL_origin = '';
			ChapterFormat = Format;
			TransChapter = TransTitle;
			TransChapter_origin = TransTitle_origin;
			Title = BookTitle;
			Format = '';
	--		TitleLink = '';
			TransTitle = '';
			URL = '';
		end
	elseif 'speech' ~= config.CitationClass then
		Conference = '';														-- not cite conference or cite speech so make sure this is empty string
	end
	
	--local sepc = A['Separator'];
	
	-- CS1/2 mode
	local Mode;
		--[[if cfg.global_cs1_config_t['Mode'] then									-- global setting in {{cs1 config}} overrides local |mode= parameter value; nil when empty or assigned value invalid
			Mode = is_valid_parameter_value (cfg.global_cs1_config_t['Mode'], 'cs1 config: mode', cfg.keywords_lists['mode'], '');	-- error messaging 'param' here is a hoax
		else]]
			Mode = is_valid_parameter_value (A['Mode'], A:ORIGIN('Mode'), cfg.keywords_lists['mode'], '');
		--end

		--[[if cfg.global_cs1_config_t['Mode'] and utilities.is_set (A['Mode']) then	-- when template has |mode=<something> which global setting has overridden
			utilities.set_message ('maint_overridden_setting');					-- set a maint message
		end]]

	-- separator character and postscript
	local sepc, PostScript = set_style (Mode:ulower(), A['PostScript'], config.CitationClass);
	-- controls capitalization of certain static text
	local use_lowercase = ( sepc == ',' );
	-- керує оформленням посилання якщо дсту
	local is_dstu = ('dstu2006' == Mode:ulower());
	-- controls capitalization of certain static text
	local use_uppercase = (sepc == '.' or is_dstu);
    
    -- cite map oddities
    local Cartography = "";
	local Scale = "";
	local Sheet = A['Sheet'] or ''; 
	local Sheets = A['Sheets'] or '';
	if config.CitationClass == "map" then
		if utilities.is_set (Chapter) then										--TODO: make a function for this and similar?
			utilities.set_message ('err_redundant_parameters', {wrap ('parameter', 'map') .. cfg.presentation['sep_list_pair'] .. wrap ('parameter', Chapter_origin)});	-- add error message
		end
		Chapter = A['Map'];
		Chapter_origin = A:ORIGIN('Map');
		ChapterURL = A['MapURL'];
		ChapterURL_origin = A:ORIGIN('MapURL');
		TransChapter = A['TransMap'];
		ScriptChapter = A['ScriptMap'];
		ScriptChapter_origin = A:ORIGIN('ScriptMap');

		ChapterUrlAccess = MapUrlAccess;
		ChapterFormat = A['MapFormat'];

		Cartography = A['Cartography'];
		if utilities.is_set ( Cartography ) then
			Cartography = sepc .. " " .. wrap_msg ('cartography', Cartography, use_lowercase);
		end		
		Scale = A['Scale'];
		if utilities.is_set ( Scale ) then
			Scale = sepc .. " " .. Scale;
		end
	end
	
	local Series = A['Series'];
	-- Account for the oddity that is {{cite episode}} and {{cite serial}}, before generation of COinS data.
    if 'episode' == config.CitationClass or 'serial' == config.CitationClass then
		local SeriesLink = A['SeriesLink'];

		SeriesLink = link_title_ok (SeriesLink, A:ORIGIN ('SeriesLink'), Series, 'series');	-- check for wiki-markup in |series-link= or wiki-markup in |series= when |series-link= is set

		local Network = A['Network'];
		local Station = A['Station'];
		local s, n = {}, {};
																				-- do common parameters first
		if utilities.is_set (Network) then table.insert(n, Network); end
		if utilities.is_set (Station) then table.insert(n, Station); end
		ID = table.concat(n, sepc .. ' ');
		
		if 'episode' == config.CitationClass then								-- handle the oddities that are strictly {{cite episode}}
			local Season = A['Season'];
			local SeriesNumber = A['SeriesNumber'];

			if utilities.is_set (Season) and utilities.is_set (SeriesNumber) then	-- these are mutually exclusive so if both are set TODO: make a function for this and similar?
				utilities.set_message ('err_redundant_parameters', {utilities.wrap_style ('parameter', 'season') .. cfg.presentation['sep_list_pair'] .. utilities.wrap_style ('parameter', 'seriesno')});		-- add error message
				SeriesNumber = '';												-- unset; prefer |season= over |seriesno=
			end
																				-- assemble a table of parts concatenated later into Series
			if utilities.is_set (Season) then table.insert(s, wrap_msg ('season', Season, use_lowercase)); end
			if utilities.is_set (SeriesNumber) then table.insert(s, wrap_msg ('seriesnum', SeriesNumber, use_lowercase)); end
			if utilities.is_set (Issue) then table.insert(s, wrap_msg ('episode', Issue, use_lowercase)); end
			Issue = '';															-- unset because this is not a unique parameter
	
			Chapter = Title;													-- promote title parameters to chapter
			ScriptChapter = ScriptTitle;
			ScriptChapter_origin = A:ORIGIN('ScriptTitle');
			ChapterLink = TitleLink;											-- alias |episode-link=
			TransChapter = TransTitle;
			ChapterURL = URL;
			ChapterUrlAccess = UrlAccess;
			ChapterURL_origin = URL_origin;
			ChapterFormat = Format;

			Title = Series;														-- promote series to title
			TitleLink = SeriesLink;
			Series = table.concat(s, sepc .. ' ');								-- this is concatenation of season, seriesno, episode number

			if utilities.is_set (ChapterLink) and not utilities.is_set (ChapterURL) then	-- link but not URL
				Chapter = utilities.make_wikilink (ChapterLink, Chapter); 
			elseif utilities.is_set (ChapterLink) and utilities.is_set (ChapterURL) then	-- if both are set, URL links episode;
				Series = utilities.make_wikilink (ChapterLink, Series);
			end
			URL = '';															-- unset
			TransTitle = '';
			ScriptTitle = '';
			Format = '';
			
		else																	-- now oddities that are cite serial
			Issue = '';															-- unset because this parameter no longer supported by the citation/core version of cite serial
			Chapter = A['Episode'];												-- TODO: make |episode= available to cite episode someday?
			if utilities.is_set (Series) and utilities.is_set (SeriesLink) then
				Series = utilities.make_wikilink (SeriesLink, Series);
			end
			Series = utilities.wrap_style ('italic-title', Series);				-- series is italicized
		end	
	end
	-- end of {{cite episode}} stuff
	
    local TitleType = A['TitleType'];
    local Degree = A['Degree'];
    if utilities.in_array (config.CitationClass, {'AV-media-notes', 'document', 'interview', 'mailinglist', 'map', 'podcast', 'pressrelease', 'report', 'speech', 'techreport', 'thesis'}) then
		TitleType = set_titletype (config.CitationClass, TitleType);
		if utilities.is_set (Degree) and "Дипломна робота" == TitleType then				-- special case for cite thesis
			TitleType =cfg.title_types ['thesis'] .. ' ' .. Degree;
		end
    end
	
	-- legacy: promote PublicationDate to Date if neither Date nor Year are set.
	local Date = A['Date'];
--	local Date_origin;															-- to hold the name of parameter promoted to Date; required for date error messaging (на майбутнє)
    local PublicationDate = A['PublicationDate'];
    local LayDate = A['LayDate'];
    local Year = A['Year'];

    local ArchiveURL = A['ArchiveURL'];
    local ArchiveDate = A['ArchiveDate'];
    local ArchiveFormat = A['ArchiveFormat'];
    
    ArchiveFormat = style_format (ArchiveFormat, ArchiveURL, 'archive-format', 'archive-url');
    
    local AccessDate = A['AccessDate'];
    local DoiBroken = A['DoiBroken'];
   -- local ASINTLD = A['ASINTLD'];
    local IgnoreISBN = A['IgnoreISBN'];
    local Embargo = A['Embargo'];
    local anchor_year;
    
    --do	-- create defined block to contain local variables error_message, date_parameters_list, mismatch
    --	local date_parameters_list = {                                           (додано буде в наступних оновленнях)
		--	['access-date'] = {val = AccessDate, name = A:ORIGIN ('AccessDate')},
		--	['archive-date'] = {val = ArchiveDate, name = A:ORIGIN ('ArchiveDate')},
		--	['date'] = {val = Date, name = Date_origin},
		--	['doi-broken-date'] = {val = DoiBroken, name = A:ORIGIN ('DoiBroken')},
	--		['pmc-embargo-date'] = {val = Embargo, name = A:ORIGIN ('Embargo')},
		--	['publication-date'] = {val = PublicationDate, name = A:ORIGIN ('PublicationDate')},
		--	['year'] = {val = Year, name = A:ORIGIN ('Year')},
	--		};
		
	--	local error_list = {};
	--	anchor_year, Embargo = validation.dates(date_parameters_list, COinS_date, error_list);
		
	--	if 0 == #error_list then												-- error free dates only; 0 when error_list is empty
			
			if  utilities.is_set(Embargo) then
				Embargo = ParseDateIfPossible(Embargo, true)                   --translates dates from Ukrainian to English, as lang:formatdate() doesn't work with Ukrainian month's names
			end
			
	--		if modified then													-- if the date_parameters_list values were modified
			--	AccessDate = date_parameters_list['access-date'].val;			-- overwrite date holding parameters with modified values
			--	ArchiveDate = date_parameters_list['archive-date'].val;
			--	Date = date_parameters_list['date'].val;
			--	DoiBroken = date_parameters_list['doi-broken-date'].val;
			--	PublicationDate = date_parameters_list['publication-date'].val;
	--		end
	--	else
	--		utilities.set_message ('err_bad_date', {utilities.make_sep_list (#error_list, error_list)});	-- add this error message
	--	end
	--end	-- end of do 

    local ID_list = {};
    local ID_list_coins = {};													-- table of identifiers and their values from args; key is same as cfg.id_handlers's key
	local Class = A['Class'];													-- arxiv class identifier
	
	local ID_support = {
		{A['ASINTLD'], 'ASIN', 'err_asintld_missing_asin', A:ORIGIN ('ASINTLD')},				
		{DoiBroken, 'DOI', 'err_doibroken_missing_doi', A:ORIGIN ('DoiBroken')},
		{Embargo, 'PMC', 'err_embargo_missing_pmc', A:ORIGIN ('Embargo')},
		}

	ID_list, ID_list_coins = identifiers.identifier_lists_get (args, {DoiBroken = DoiBroken, IgnoreISBN = IgnoreISBN, ASINTLD = A['ASINTLD'], Embargo = Embargo, Class = Class}, ID_support);
    
    -- Account for the oddities that are {{cite arxiv}}, {{cite biorxiv}}, {{cite citeseerx}}, {{cite medrxiv}}, {{cite ssrn}}, before generation of COinS data.
	if utilities.in_array (config.CitationClass, whitelist.preprint_template_list_t) then	-- |arxiv= or |eprint= required for cite arxiv; |biorxiv=, |citeseerx=, |medrxiv=, |ssrn= required for their templates
		if not (args[cfg.id_handlers[config.CitationClass:upper()].parameters[1]] or 		-- can't use ID_list_coins k/v table here because invalid parameters omitted
			args[cfg.id_handlers[config.CitationClass:upper()].parameters[2]]) then			-- which causes unexpected parameter missing error message
				utilities.set_message ('err_' .. config.CitationClass .. '_missing');		-- add error message
		end

		Periodical = ({['arxiv'] = 'arXiv', ['biorxiv'] = 'bioRxiv', ['citeseerx'] = 'CiteSeerX', ['medrxiv'] = 'medRxiv', ['ssrn'] = 'Social Science Research Network'})[config.CitationClass];
	end
	
	-- Link the title of the work if no |url= was provided, but we have a |pmc= or a |doi= with |doi-access=free

	if config.CitationClass == "journal" and not utilities.is_set (URL) and not utilities.is_set (TitleLink) and not utilities.in_array (cfg.keywords_xlate[Title], {'off', 'none'}) then -- TODO: remove 'none' once existing citations have been switched to 'off', so 'none' can be used as token for "no title" instead
		if 'none' ~= cfg.keywords_xlate[auto_select] then						-- if auto-linking not disabled
 	 		if identifiers.auto_link_urls[auto_select] then						-- manual selection
		 		URL = identifiers.auto_link_urls[auto_select];					-- set URL to be the same as identifier's external link
 				URL_origin = cfg.id_handlers[auto_select:upper()].parameters[1];	-- set URL_origin to parameter name for use in error message if citation is missing a |title=
			elseif identifiers.auto_link_urls['pmc'] then						-- auto-select PMC
				URL = identifiers.auto_link_urls['pmc'];						-- set URL to be the same as the PMC external link if not embargoed
				URL_origin = cfg.id_handlers['PMC'].parameters[1];				-- set URL_origin to parameter name for use in error message if citation is missing a |title=
			elseif identifiers.auto_link_urls['doi'] then						-- auto-select DOI
				URL = identifiers.auto_link_urls['doi'];
				URL_origin = cfg.id_handlers['DOI'].parameters[1];
			end
 	 	end

		if utilities.is_set (URL) then											-- set when using an identifier-created URL
			if utilities.is_set (AccessDate) then								-- |access-date= requires |url=; identifier-created URL is not |url=
				utilities.set_message ('err_accessdate_missing_url');			-- add an error message
				AccessDate = '';												-- unset
			end

			if utilities.is_set (ArchiveURL) then								-- |archive-url= requires |url=; identifier-created URL is not |url=
				utilities.set_message ('err_archive_missing_url');				-- add an error message
				ArchiveURL = '';												-- unset
			end
		end
	end
    
    local LayURL = A['LayURL'];
    local LaySource = A['LaySource'];
    local Transcript = A['Transcript'];
    local TranscriptURL = A['TranscriptURL'] 
    local TranscriptURL_origin = A:ORIGIN('TranscriptURL');
    local LastAuthorAmp = A['LastAuthorAmp'];
	
	-- At this point fields may be nil if they weren't specified in the template use.  We can use that fact.
	-- Test if citation has no title
	if	not utilities.is_set (Title) and not utilities.is_set (TransTitle) and not utilities.is_set (ScriptTitle) then	-- has special case for cite episode
		utilities.set_message ('err_citation_missing_title', {'episode' == config.CitationClass and 'series' or 'title'});
	end
	
	if utilities.in_array (cfg.keywords_xlate[Title], {'off', 'none'}) and
			utilities.in_array (config.CitationClass, {'journal', 'citation'}) and
			(utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and
			('journal' == Periodical_origin or 'script-journal' == ScriptPeriodical_origin) then	-- special case for journal cites
				Title = '';														-- set title to empty string
				utilities.set_message ('maint_untitled');						-- add maint cat
	end
	
	-- COinS metadata (see <http://ocoins.info/>) for automated parsing of citation information.
	-- handle the oddity that is cite encyclopedia and {{citation |encyclopedia=something}}. Here we presume that
	-- when Periodical, Title, and Chapter are all set, then Periodical is the book (encyclopedia) title, Title
	-- is the article title, and Chapter is a section within the article.  So, we remap 
	
	local coins_chapter = Chapter;												-- default assuming that remapping not required
	local coins_title = Title;													-- et tu
	if 'encyclopaedia' == config.CitationClass or ('citation' == config.CitationClass and utilities.is_set (Encyclopedia)) then
		if utilities.is_set (Chapter) and utilities.is_set (Title) and utilities.is_set (Periodical) then		-- if all are used then
			coins_chapter = Title;												-- remap
			coins_title = Periodical;
		end
	end
    
	-- this is the function call to COinS()
    local OCinSoutput = metadata.COinS({
        ['Periodical'] = Periodical,
        ['Chapter'] = metadata.make_coins_title(coins_chapter, ScriptChapter),
        ['Title'] = metadata.make_coins_title (coins_title, ScriptTitle),
        ['PublicationPlace'] = PublicationPlace,
        ['Date'] = first_set({Date, Year, PublicationDate}, 3),
        ['Degree'] = Degree;													-- cite thesis only
        ['Series'] = Series,
        ['Volume'] = Volume,
        ['Issue'] = Issue,
        ['ArticleNumber'] = ArticleNumber,
        ['Pages'] = coins_pages or metadata.get_coins_pages (first_set ({Sheet, Sheets, Page, Pages, At, --[[QuotePage, QuotePages]]}, 7)),
        ['Edition'] = Edition,
        ['PublisherName'] = PublisherName,
        ['URL'] = first_set( {URL, ChapterURL}, 2 ),
        ['Authors'] = a,
        ['ID_list'] = ID_list_coins,
        ['RawPage'] = this_page.prefixedText,
    }, config.CitationClass);
    
    -- Account for the oddities that are {{cite arxiv}}, {{cite biorxiv}}, {{cite citeseerx}}, {{cite medrxiv}}, and {{cite ssrn}} AFTER generation of COinS data.
	if utilities.in_array (config.CitationClass, whitelist.preprint_template_list_t) then	-- we have set rft.jtitle in COinS to arXiv, bioRxiv, CiteSeerX, medRxiv, or ssrn now unset so it isn't displayed
		Periodical = '';														-- periodical not allowed in these templates; if article has been published, use cite journal
	end
    
    local Translators;															-- assembled translators name list
	local translator_etal;
	local t = {};																-- translators list from |translator-lastn= / translator-firstn= pairs
	t = extract_names (args, 'TranslatorList');									-- fetch translator list from |translatorn= / |translator-lastn=, -firstn=, -linkn=, -maskn=
	local Interviewers;															
	local interviewers_list = {};					
	interviewers_list = extract_names (args, 'InterviewerList');				-- process preferred interviewers parameters
	local interviewer_etal;

    -- Now perform various field substitutions.
    -- We also add leading spaces and surrounding markup and punctuation to the
    -- various parts of the citation, but only when they are non-nil.
    do
    	local last_first_list;
        local control = { 
            sep = nil,
            namesep = nil,
            format = NameListStyle,												-- empty string, '&', 'amp', 'and', or 'vanc' (у новій версії)
            maximum = nil,														-- as if display-authors or display-editors not set
            lastauthoramp = nil
        };

        do
            control.sep = A["AuthorSeparator"] .. " ";
            control.namesep = (first_set({A["AuthorNameSeparator"], A["NameSeparator"]}, 2) or "") .. " ";
            control.maximum, author_etal = get_display_names (A['DisplayAuthors'], #a, 'authors', author_etal, A:ORIGIN ('DisplayAuthors'));
            control.lastauthoramp = LastAuthorAmp;
        
            -- If the coauthor field is also used, prevent ampersand and et al. formatting.
            if utilities.is_set(Coauthors) then
                control.lastauthoramp = nil;
                control.maximum = #a + 1;
            end
        
            last_first_list = list_people(control, a, author_etal, is_dstu); 
            
            if utilities.is_set (Authors) then
				Authors, author_etal = name_has_etal (Authors, author_etal, true, 'authors');	-- find and remove variations on et al.
				if author_etal then
					Authors = Authors .. ' ' .. cfg.messages['et al'];			-- add et al. to authors parameter
				end
			else
				Authors = last_first_list;										-- either an author name list or an empty string
			end
        end
        do
            control.sep = A["EditorSeparator"] .. " ";
            control.namesep = (first_set({A["EditorNameSeparator"], A["NameSeparator"]}, 2) or "") .. " ";
            control.maximum, editor_etal = get_display_names (A['DisplayEditors'], #e, 'editors', editor_etal, A:ORIGIN ('DisplayEditors'));
            control.lastauthoramp = LastAuthorAmp;

            last_first_list, EditorCount = list_people(control, e, editor_etal, is_dstu);
            
            if utilities.is_set (Editors) then
            	EditorCount = 1;
				Editors, editor_etal = name_has_etal (Editors, editor_etal, true, 'editors');	-- find and remove variations on et al.
				if editor_etal then
					Editors = Editors .. ' ' .. cfg.messages['et al'];			-- add et al. to authors parameter
				end
			else
				Editors = last_first_list;										-- either an author name list or an empty string
			end
        end
        do
            control.maximum, interviewer_etal = get_display_names (A['DisplayInterviewers'], #interviewers_list, 'interviewers', interviewer_etal, A:ORIGIN ('DisplayInterviewers'));

            Interviewers = list_people (control, interviewers_list, interviewer_etal, is_dstu);
        end
        do
            control.maximum, translator_etal = get_display_names (A['DisplayTranslators'], #t, 'translators', translator_etal, A:ORIGIN ('DisplayTranslators'));

            Translators = list_people (control, t, translator_etal, is_dstu);
        end
    end
    
    local ConferenceURL = A['ConferenceURL'];
    
    if not utilities.is_set(Date) then
        Date = Year;
        if utilities.is_set(Date) then
            local Month = A['Month'];
            if utilities.is_set(Month) then 
                Date = Month .. " " .. Date;
                local Day = A['Day']
                if utilities.is_set(Day) then Date = Day .. " " .. Date end
            end
        end
    end
    
    if utilities.in_array(PublicationDate, {Date, Year}) then PublicationDate = ''; end
    if not utilities.is_set(Date) and utilities.is_set(PublicationDate) then
        Date = PublicationDate;
        PublicationDate = '';
    end

    -- Captures the value for Date prior to adding parens or other textual transformations
    local DateIn = Date;
    
    local ConferenceFormat = A['ConferenceFormat'];
	local ConferenceURL = A['ConferenceURL'];
	ConferenceFormat = style_format (ConferenceFormat, ConferenceURL, 'conference-format', 'conference-url');
	Format = style_format (Format, URL, 'format', 'url');
	
		-- special case for chapter format so no error message or cat when chapter not supported
	if not (utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'arxiv', 'biorxiv', 'citeseerx', 'medrxiv', 'ssrn'}) or
		('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia))) then
			ChapterFormat = style_format (ChapterFormat, ChapterURL, 'chapter-format', 'chapter-url');
	end
  
    if  not utilities.is_set(URL) then
		if utilities.in_array (config.CitationClass, {"web", "podcast", "mailinglist"}) or		-- |url= required for cite web, cite podcast, and cite mailinglist
			('citation' == config.CitationClass and ('website' == Periodical_origin or 'script-website' == ScriptPeriodical_origin)) then	-- and required for {{citation}} with |website= or |script-website=
				utilities.set_message ('err_cite_web_url');
		end
        
    	-- do we have |accessdate= without either |url= or |chapter-url=?
		if utilities.is_set (AccessDate) and not utilities.is_set (ChapterURL) then		-- ChapterURL may be set when URL is not set;
			utilities.set_message ('err_accessdate_missing_url');
			AccessDate = '';
		end
    end
    
    local UrlStatus = is_valid_parameter_value (A['UrlStatus'], A:ORIGIN('UrlStatus'), cfg.keywords_lists['url-status'], '');
    local DeadURL = is_valid_parameter_value (A['DeadURL'], A:ORIGIN('DeadURL'), cfg.keywords_lists['DeadURL'], '');
    local OriginalURL
	local OriginalURL_origin
	local OriginalFormat
	local OriginalAccess;
	DeadURL = DeadURL:lower();
	
	if utilities.is_set (DeadURL) then
		if not utilities.is_set (UrlStatus) then									
			UrlStatus = 'yes' == DeadURL and 'live' or 'dead';					-- якщо не встанолено UrlStatus і встановлено DeadURL, то значення DeadURL передаємо UrlStatus
		else
			utilities.set_message ('err_redundant_parameters', {utilities.make_sep_list (2, {utilities.wrap_style ('parameter', A:ORIGIN('UrlStatus')), utilities.wrap_style ('parameter', A:ORIGIN('DeadURL'))})}); -- виводимо помилку, якщо зазначено і DeadURL і UrlStatus
		end	
	end	
	
    UrlStatus = UrlStatus:lower();
    if utilities.is_set ( ArchiveURL ) then
		if utilities.is_set (ChapterURL) then 									-- if chapter-url= is set apply archive url to it
			OriginalURL = ChapterURL;											-- save copy of source chapter's url for archive text
			OriginalURL_origin = ChapterURL_origin;								-- name of |chapter-url= parameter for error messages
			OriginalFormat = ChapterFormat;										-- and original |chapter-format=

			if ('live' ~= UrlStatus) then
				ChapterURL = ArchiveURL											-- swap-in the archive's URL
				ChapterURL_origin = A:ORIGIN('ArchiveURL')						-- name of |archive-url= parameter for error messages
				ChapterFormat = ArchiveFormat or '';							-- swap in archive's format
				ChapterUrlAccess = nil;											-- restricted access levels do not make sense for archived URLs
			end
		elseif utilities.is_set (URL) then
			OriginalURL = URL;													-- save copy of original source URL
			OriginalURL_origin = URL_origin;									-- name of URL parameter for error messages
			OriginalFormat = Format; 											-- and original |format=
			OriginalAccess = UrlAccess;

			if ('live' ~= UrlStatus) then											-- if URL set then |archive-url= applies to it
				URL = ArchiveURL												-- swap-in the archive's URL
				URL_origin = A:ORIGIN('ArchiveURL')								-- name of archive URL parameter for error messages
				Format = ArchiveFormat or '';									-- swap in archive's format
				UrlAccess = nil;												-- restricted access levels do not make sense for archived URLs
			end
		end
	elseif utilities.is_set (UrlStatus) then									-- if |url-status= is set when |archive-url= is not set
 		utilities.set_message ('maint_url_status');								-- add maint cat
	end
    
    local trans_quoted_title;
    local trans_italic_title;
    if is_dstu then
    	trans_quoted_title = 'dstu-trans-quoted-title';
    	trans_italic_title = 'dstu-trans-italic-title';
    else
    	trans_quoted_title = 'trans-quoted-title';
    	trans_italic_title = 'trans-italic-title';
    end
    
    if utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'arxiv', 'biorxiv', 'citeseerx', 'medrxiv', 'ssrn'}) or	-- if any of the 'periodical' cites except encyclopedia
		('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia)) then
			local chap_param;
			if utilities.is_set (Chapter) then									-- get a parameter name from one of these chapter related meta-parameters
				chap_param = A:ORIGIN ('Chapter')
			elseif utilities.is_set (TransChapter) then
				chap_param = A:ORIGIN ('TransChapter')
			elseif utilities.is_set (ChapterURL) then
				chap_param = A:ORIGIN ('ChapterURL')
			elseif utilities.is_set (ScriptChapter) then
				chap_param = ScriptChapter_origin;
			else utilities.is_set (ChapterFormat)
				chap_param = A:ORIGIN ('ChapterFormat')
			end

			if utilities.is_set (chap_param) then								-- if we found one
				utilities.set_message ('err_chapter_ignored', {chap_param});	-- add error message
				Chapter = '';													-- and set them to empty string to be safe with concatenation
				TransChapter = '';
				ChapterURL = '';
				ScriptChapter = '';
				ChapterFormat = '';
			end
    else
    local no_quotes = false;												-- default assume that we will be quoting the chapter parameter value
	--	if utilities.is_set (Contribution) and 0 < #c then						-- if this is a contribution with contributor(s) (не підтримується цей параметр)
	--		if utilities.in_array (Contribution:lower(), cfg.keywords_lists.contribution) then	-- and a generic contribution title
	--			no_quotes = true;												-- then render it unquoted
	--		end
	--	end

		Chapter = format_chapter_title (ScriptChapter, ScriptChapter_origin, Chapter, Chapter_origin, TransChapter, TransChapter_origin, ChapterURL, ChapterURL_origin, no_quotes, ChapterUrlAccess);		-- Contribution is also in Chapter
		if utilities.is_set (Chapter) then
			Chapter = Chapter .. ChapterFormat ;
			if 'map' == config.CitationClass and utilities.is_set (TitleType) then
				Chapter = Chapter .. ' ' .. TitleType;							-- map annotation here; not after title
			end
			Chapter = Chapter .. sepc .. ' ';
		elseif utilities.is_set (ChapterFormat) then							-- |chapter= not set but |chapter-format= is so ...
			Chapter = ChapterFormat .. sepc .. ' ';								-- ... ChapterFormat has error message, we want to see it
		end
	end
    
    -- Format main title.
    local plain_title = false;
	local accept_title;
	Title, accept_title = utilities.has_accept_as_written (Title, true);		-- remove accept-this-as-written markup when it wraps all of <Title>
	if accept_title and ('' == Title) then										-- only support forced empty for now "(())"
		Title = cfg.messages['notitle'];										-- replace by predefined "No title" message
			-- TODO: utilities.set_message ( 'err_redundant_parameters', ...);	-- issue proper error message instead of muting	 
			ScriptTitle = '';													-- just mute for now	 
			TransTitle = '';													-- just mute for now
 		plain_title = true;														-- suppress text decoration for descriptive title
		utilities.set_message ('maint_untitled');								-- add maint cat
	end
    
    	if not accept_title then													-- <Title> not wrapped in accept-as-written markup
		if '...' == Title:sub (-3) then											-- if ellipsis is the last three characters of |title=
			Title = Title:gsub ('(%.%.%.)%.+$', '%1');							-- limit the number of dots to three
		elseif not mw.ustring.find (Title, '%.%s*%a%.$') and					-- end of title is not a 'dot-(optional space-)letter-dot' initialism ...
			not mw.ustring.find (Title, '%s+%a%.$') then						-- ...and not a 'space-letter-dot' initial (''Allium canadense'' L.)
				Title = mw.ustring.gsub(Title, '%' .. sepc .. '$', '');			-- remove any trailing separator character; sepc and ms.ustring() here for languages that use multibyte separator characters
		end

		if utilities.is_set (ArchiveURL) and is_archived_copy (Title) then
			utilities.set_message ('maint_archived_copy');						-- add maintenance category before we modify the content of Title
		end

	--	if is_generic ('generic_titles', Title) then
	--		utilities.set_message ('err_generic_title');						-- set an error message
	--	end
	end

	if (not plain_title) and (utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'document', 'pressrelease', 'podcast', 'newsgroup', 'mailinglist', 'interview', 'arxiv', 'biorxiv', 'citeseerx', 'medrxiv', 'ssrn'}) or
		('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia)) or
		('map' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)))) then		-- special case for cite map when the map is in a periodical treat as an article
		--	Title = kern_quotes (Title);										-- if necessary, separate title's leading and trailing quote marks from module provided quote marks
			Title = utilities.wrap_style ('quoted-title', Title);
			Title = script_concatenate (Title, ScriptTitle, 'script-title');	-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
			TransTitle = utilities.wrap_style ('trans-quoted-title', TransTitle );
	elseif plain_title or ('report' == config.CitationClass) then				-- no styling for cite report and descriptive titles (otherwise same as above)
		Title = script_concatenate (Title, ScriptTitle, 'script-title');		-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
		TransTitle = utilities.wrap_style ('trans-quoted-title', TransTitle );	-- for cite report, use this form for trans-title
	else
		Title = utilities.wrap_style ('italic-title', Title);
		Title = script_concatenate (Title, ScriptTitle, 'script-title');		-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
		TransTitle = utilities.wrap_style ('trans-italic-title', TransTitle);
	end

	if utilities.is_set (TransTitle) then
		if utilities.is_set (Title) then
			TransTitle = " " .. TransTitle;
		else
			utilities.set_message ('err_trans_missing_title', {'title'});
		end
	end

	if utilities.is_set (Title) then											-- TODO: is this the right place to be making Wikisource URLs?
		if utilities.is_set (TitleLink) and utilities.is_set (URL) then
			utilities.set_message ('err_wikilink_in_url');						-- set an error message because we can't have both
			TitleLink = '';														-- unset
		end
	
		if not utilities.is_set (TitleLink) and utilities.is_set (URL) then
			Title = external_link (URL, Title, URL_origin, UrlAccess) .. TransTitle .. Format;
			URL = '';															-- unset these because no longer needed
			Format = "";
		elseif utilities.is_set (TitleLink) and not utilities.is_set (URL) then
			local ws_url;
			ws_url = wikisource_url_make (TitleLink);							-- ignore ws_label return; not used here
			if ws_url then
				Title = external_link (ws_url, Title .. '&nbsp;', 'ws link in title-link');	-- space char after Title to move icon away from italic text; TODO: a better way to do this?
				Title = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], TitleLink, Title});				
				Title = Title .. TransTitle;
			else
				Title = utilities.make_wikilink (TitleLink, Title) .. TransTitle;
			end
		else
			local ws_url, ws_label, L;											-- Title has italic or quote markup by the time we get here which causes is_wikilink() to return 0 (not a wikilink)
			ws_url, ws_label, L = wikisource_url_make (Title:gsub('^[\'"]*(.-)[\'"]*$', '%1'));	-- make ws URL from |title= interwiki link (strip italic or quote markup); link portion L becomes tooltip label
			if ws_url then
				Title = Title:gsub ('%b[]', ws_label);							-- replace interwiki link with ws_label to retain markup
				Title = external_link (ws_url, Title .. '&nbsp;', 'ws link in title');	-- space char after Title to move icon away from italic text; TODO: a better way to do this?
				Title = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, Title});				
				Title = Title .. TransTitle;
			else
				Title = Title .. TransTitle;
			end
		end
	else
		Title = TransTitle;
	end
    
    if utilities.is_set (Place) then
		Place = " " .. wrap_msg ('written', Place, use_lowercase) .. sepc .. " ";
	end
    
    local ConferenceURL_origin = A:ORIGIN('ConferenceURL');						-- get name of parameter that holds ConferenceURL
	if utilities.is_set (Conference) then
		if utilities.is_set (ConferenceURL) then
			Conference = external_link( ConferenceURL, Conference, ConferenceURL_origin, nil );
		end
		Conference = sepc .. " " .. Conference .. ConferenceFormat;
	elseif utilities.is_set (ConferenceURL) then
		Conference = sepc .. " " .. external_link( ConferenceURL, nil, ConferenceURL_origin, nil );
	end
    
	local Position = '';
    if not utilities.is_set(Position) then
        local Minutes = A['Minutes'];
        if utilities.is_set(Minutes) then
            Position = " " .. wrap_msg ('minutes', Minutes, use_lowercase);
        else
            local Time = A['Time'];
            if utilities.is_set(Time) then
                local TimeCaption = A['TimeCaption']
                if not utilities.is_set(TimeCaption) then
                    TimeCaption = cfg.messages['event'];
                    if not use_uppercase then
                        TimeCaption = TimeCaption:ulower();
                    end
                end
                Position = " " .. TimeCaption .. " " .. Time;
            end
        end
    else
        Position = " " .. Position;
        At = '';
    end
    
    local colon;
    if is_dstu then
    	colon = cfg.presentation['sep_colon_dstu2006'];
    else
    	colon = ": ";
    end
    
    Page, Pages, Sheet, Sheets = format_pages_sheets (Page, Pages, Sheet, Sheets, config.CitationClass, Periodical_origin, sepc, NoPP, use_lowercase, is_dstu);
    
    At = utilities.is_set(At) and (sepc .. " " .. At) or "";
    Position = utilities.is_set (Position) and (sepc .. " " .. Position) or "";
    if config.CitationClass == 'map' then
		local Sections = A['Sections'];											-- Section (singular) is an alias of Chapter so set earlier
		local Inset = A['Inset'];
		
		if utilities.is_set ( Inset ) then
			Inset = sepc .. " " .. wrap_msg ('inset', Inset, use_lowercase);
		end			

		if utilities.is_set ( Sections ) then
			Section = sepc .. " " .. wrap_msg ('sections', Sections, use_lowercase);
		elseif utilities.is_set ( Section ) then
			Section = sepc .. " " .. wrap_msg ('section', Section, use_lowercase);
		end
		At = At .. Inset .. Section;		
    end	
    
    Others = utilities.is_set(Others) and (sepc .. " " .. Others) or "";
    
    if utilities.is_set (Translators) then
		Others = safe_join ({sepc .. ' ', wrap_msg ('translated', Translators, use_lowercase), Others}, sepc);
    end
	if utilities.is_set (Interviewers) then
		Others = safe_join ({sepc .. ' ', wrap_msg ('interview', Interviewers, use_lowercase), Others}, sepc);
	end
    
    if utilities.is_set(TitleType) then
    	--if is_dstu then
    		--if not utilities.is_set(Publisher) and utilities.is_set(Language) then
    		--	TitleType = cfg.presentation['sep_colon_dstu2006'] .. TitleType;
    		--else
    		--	TitleType = cfg.presentation['sep_colon_dstu2006'] .. TitleType;
    		--end
    	--else
    		TitleType = " (" .. TitleType .. ")";
    	--end
    else
    	TitleType = "";
    end	
    
    local TitleNote = A['TitleNote'];
    TitleNote = utilities.is_set(TitleNote) and (sepc .. " " .. TitleNote) or "";
    
    local Language = A['Language'];
	if utilities.is_set (Language) then
		Language = language_parameter (Language, is_dstu);						-- format, categories, name from ISO639-1, etc.
	else
		Language='';															-- language not specified so make sure this is an empty string;
	--[[ TODO: need to extract the wrap_msg from language_parameter
	so that we can solve parentheses bunching problem with Format/Language/TitleType
	]]
	end
    
    Edition = utilities.is_set(Edition) and (" " .. wrap( 'edition', Edition )) or "";
    Series = utilities.is_set (Series) and wrap_msg ('series', {sepc, Series}) or "";	-- not the same as SeriesNum
	local Agency = A['Agency'];
    Agency = utilities.is_set(Agency) and (sepc .. " " .. Agency) or "";
    
    Volume = format_volume_issue (Volume, Issue, ArticleNumber, config.CitationClass, Periodical_origin, sepc, use_lowercase);
    
    ------------------------------------ totally unrelated data
    if utilities.is_set(AccessDate) then
    	local retrv_text;
    	if is_dstu then
    		retrv_text = " " .. cfg.messages['dsturetrieved']
    	else	
        	retrv_text = " " .. cfg.messages['retrieved']
        end	
        if not use_uppercase then retrv_text = retrv_text:ulower() end
        AccessDate = ParseDateIfPossible(AccessDate)
        AccessDate = '<span class="reference-accessdate">' .. sepc
            .. utilities.substitute( retrv_text, {AccessDate} ) .. '</span>'
    end
    
    if utilities.is_set(ID) then ID = sepc .." ".. ID; end

    if utilities.is_set(URL) then
        URL = " " .. external_link( URL, nil, URL_origin, UrlAccess);
    end
    
    local Quote = A['Quote'];
    local ScriptQuote = A['ScriptQuote'];
    local TransQuote = A['TransQuote'];

    if utilities.is_set(Quote) or utilities.is_set(TransQuote) or utilities.is_set (ScriptQuote) then
    	if utilities.is_set(Quote) then
        	if Quote:sub(1,1) == '"' and Quote:sub(-1,-1) == '"' then
            	Quote = Quote:sub(2,-2);
        	end
    	end
    	
    	if utilities.is_set (ScriptQuote) then
			Quote = script_concatenate (Quote, ScriptQuote, 'script-quote');	-- <bdi> tags, lang attribute, categorization, etc.; must be done after quote is wrapped;
			if Quote:sub(1,1) == " " then                                       -- після конкатування двох string додався пробіл, перевіряє чи не наявний пробілу на початку рядка
				Quote = Quote:sub(2,-1);                                        -- прибирання зайвого пробілу
			end
		end
        
        if utilities.is_set (TransQuote) then
        	if not utilities.is_set(Quote) then
        		utilities.set_message('err_trans_missing_quote');
        	else
				if TransQuote:sub(1, 1) == '"' and TransQuote:sub(-1, -1) == '"' then -- if first and last characters of |trans-quote are quote marks
					TransQuote = TransQuote:sub(2, -2); -- strip them off
				end
				TransQuote = " " .. utilities.wrap_style (trans_quoted_title, TransQuote );
			end	
			Quote = Quote .. TransQuote;
        end
	
        Quote = sepc .." " .. utilities.wrap_style ( 'quoted-text', Quote ); 
        PostScript = "";
    elseif PostScript:ulower() == "none" then
        PostScript = "";
    end
    
    local Archived
    if utilities.is_set (ArchiveURL) then
		if not utilities.is_set (ArchiveDate) then								-- ArchiveURL set but ArchiveDate not set
			utilities.set_message ('err_archive_missing_date');					-- emit an error message
			ArchiveURL = "";													-- empty string for concatenation
			ArchiveDate = "";													-- empty string for concatenation
		end
	else														
		if utilities.is_set (ArchiveDate) then									-- ArchiveURL not set but ArchiveDate is set
			utilities.set_message ('err_archive_date_missing_url');				        -- emit an error message
			ArchiveURL = "";													-- empty string for concatenation
			ArchiveDate = "";													-- empty string for concatenation
		end
	end

    if utilities.is_set(ArchiveURL) then
        local arch_text;
        ArchiveDate = ParseDateIfPossible(ArchiveDate)
        if ("live" == UrlStatus) then
            arch_text = cfg.messages['archived'];
            if not use_uppercase then arch_text = arch_text:ulower() end
            if utilities.is_set (ArchiveDate) then
                Archived = sepc .. " " .. utilities.substitute( cfg.messages['archived-live'],
                    { external_link( ArchiveURL, arch_text, A:ORIGIN('ArchiveURL'), nil) .. ArchiveFormat, ArchiveDate } );
            else
				Archived = "";
			end    
            if not utilities.is_set(OriginalURL) then
                utilities.set_message('err_archive_missing_url');
                Archived = "";                                                    -- empty string for concatenation  
            end
        elseif utilities.is_set(OriginalURL) then                                -- UrlStatus is empty, 'dead', 'unfit', 'usurped', 'bot: unknown'
        	if utilities.in_array (UrlStatus, {'unfit', 'usurped', 'bot: unknown'}) then
        		arch_text = cfg.messages['archived-unfit'];
				if not use_uppercase then arch_text = arch_text:ulower() end
				Archived = sepc .. " " .. arch_text .. ArchiveDate;				-- format already styled
				if 'bot: unknown' == UrlStatus then
					utilities.set_message('maint_bot_unknown');				-- and add a category if not already added
				else
					utilities.set_message('maint_unfit');                     -- and add a category if not already added
				end
			else                                                    -- UrlStatus is empty, 'dead'
            	arch_text = cfg.messages['archived-dead'];
            	if not use_uppercase then arch_text = arch_text:ulower() end
                if utilities.is_set (ArchiveDate) then
            	    Archived = sepc .. " " .. utilities.substitute( arch_text,
                	    { external_link( OriginalURL, cfg.messages['original'], OriginalURL_origin, OriginalAccess ) .. OriginalFormat, ArchiveDate } );	-- format already styled
                else
					Archived = "";												-- unset for concatenation
				end
            end
        else																	-- OriginalUrl not set
            utilities.set_message ('err_archive_missing_url');
			Archived = "";														-- empty string for concatenation
        end
    elseif utilities.is_set (ArchiveFormat) then
		Archived = ArchiveFormat;												-- if set and ArchiveURL not set ArchiveFormat has error message    
    else
        Archived = "";
    end
    
    local Lay
    if utilities.is_set(LayURL) then
        if utilities.is_set(LayDate) then LayDate = " (" .. LayDate .. ")" end
        if utilities.is_set(LaySource) then 
            LaySource = " &ndash; ''" .. utilities.safe_for_italics(LaySource) .. "''";
        else
            LaySource = "";
        end
        if use_uppercase then
            Lay = sepc .. " " .. external_link( LayURL, cfg.messages['lay summary'] ) .. LaySource .. LayDate
        else
            Lay = sepc .. " " .. external_link( LayURL, cfg.messages['lay summary']:ulower() ) .. LaySource .. LayDate
        end            
    else
        Lay = "";
    end
    
    local TranscriptURL = A['TranscriptURL']
	local TranscriptFormat = A['TranscriptFormat'];
	TranscriptFormat = style_format (TranscriptFormat, TranscriptURL, 'transcript-format', 'transcripturl');
	local Transcript = A['Transcript'];
	local TranscriptURL_origin = A:ORIGIN('TranscriptURL');						-- get name of parameter that holds TranscriptURL
    if utilities.is_set (Transcript) then
		if utilities.is_set (TranscriptURL) then
			Transcript = external_link( TranscriptURL, Transcript, TranscriptURL_origin, nil );
		end
		Transcript = sepc .. ' ' .. Transcript .. TranscriptFormat;
	elseif utilities.is_set (TranscriptURL) then
		Transcript = external_link( TranscriptURL, nil, TranscriptURL_origin, nil );
	end
    
    local Publisher;
    if utilities.is_set (PublicationDate) then
		PublicationDate = wrap_msg ('published', PublicationDate);
	end
    if utilities.is_set(PublicationDate) then
        PublicationDate = " (" .. wrap( 'published', PublicationDate ) .. ")";
	end
	if utilities.is_set(PublisherName) then
       if utilities.is_set(PublicationPlace) then
           Publisher = sepc .. " " .. PublicationPlace .. colon .. PublisherName .. PublicationDate;
    	else
           Publisher = sepc .. " " .. PublisherName .. PublicationDate;  
    	end            
    elseif utilities.is_set(PublicationPlace) then 
        Publisher= sepc .. " " .. PublicationPlace .. PublicationDate;
	else 
    	Publisher = PublicationDate;
	end
    
    -- Several of the above rely upon detecting this as nil, so do it last.
    if (utilities.is_set(Periodical) or utilities.is_set (ScriptPeriodical) or utilities.is_set (TransPeriodical)) then
        if utilities.is_set(Title) or utilities.is_set(TitleNote) then 
            Periodical = sepc .. " " .. format_periodical (ScriptPeriodical, ScriptPeriodical_origin, Periodical, TransPeriodical, TransPeriodical_origin, trans_italic_title);
        else 
            Periodical = format_periodical (ScriptPeriodical, ScriptPeriodical_origin, Periodical, TransPeriodical, TransPeriodical_origin, trans_italic_title);
        end
    end

    -- Piece all bits together at last.  Here, all should be non-nil.
    -- We build things this way because it is more efficient in LUA
    -- not to keep reassigning to the same string variable over and over.

    local tcommon
    if utilities.in_array(config.CitationClass, {"journal","citation"}) and utilities.is_set(Periodical) then
        if not (utilities.is_set (Authors) or utilities.is_set (Editors)) then
			Others = Others:gsub ('^' .. sepc .. ' ', '');						-- when no authors and no editors, strip leading sepc and space
		end
        if utilities.is_set (Others) then Others = safe_join ({Others, sepc .. " "}, sepc) end		-- add terminal punctuation & space; check for dup sepc; TODO why do we need to do this here?
        tcommon = safe_join( {Others, Title, TitleNote, Conference, Periodical, Format, TitleType, Series, 
            Language, Edition, Publisher, Agency, Volume}, sepc );
    elseif 'map' == config.CitationClass then									-- special cases for cite map
		if utilities.is_set (Chapter) then										-- map in a book; TitleType is part of Chapter
			tcommon = safe_join( {Title, Format, Edition, Scale, Series, Language, Cartography, Others, Publisher, Volume}, sepc );
		elseif utilities.is_set (Periodical) then								-- map in a periodical
			tcommon = safe_join( {Title, TitleType, Format, Periodical, Scale, Series, Language, Cartography, Others, Publisher, Volume}, sepc );
		else																	-- a sheet or stand-alone map
			tcommon = safe_join( {Title, TitleType, Format, Edition, Scale, Series, Language, Cartography, Others, Publisher}, sepc );
		end
	elseif 'episode' == config.CitationClass then								-- special case for cite episode
		tcommon = safe_join( {Title, TitleNote, TitleType, Series, Language, Edition, Publisher}, sepc );	
    else 
        tcommon = safe_join( {Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Language, 
            Volume, Others, Edition, Publisher, Agency}, sepc );
    end
    
    if #ID_list > 0 then
        ID_list = safe_join( { sepc .. " ",  table.concat( ID_list, sepc .. " " ), ID }, sepc );
    else
        ID_list = ID;
    end
    
    local idcommon; 
    local Via = A['Via'];
    Via = utilities.is_set (Via) and  wrap_msg ('via', Via) or '';
    if 'audio-visual' == config.CitationClass or 'episode' == config.CitationClass then	-- special case for cite AV media & cite episode position transcript
		idcommon = safe_join( { ID_list, URL, Archived, Transcript, AccessDate, Via, Lay, Quote }, sepc );
	else
		idcommon = safe_join( { ID_list, URL, Archived, AccessDate, Via, Lay, Quote }, sepc );
    end

    local text;
    local pgtext = Position .. Sheet .. Sheets .. Page .. Pages .. At;
    
    local OrigDate = A['OrigDate'];
	OrigDate = utilities.is_set (OrigDate) and wrap_msg ('origdate', OrigDate) or '';
	if utilities.is_set (Date) then
		Date = ParseDateIfPossible(Date)
		if utilities.is_set (Authors) or utilities.is_set (Editors) then		-- date follows authors or editors when authors not set
			--[[if is_dstu then
				Date = " (" .. Date .. ")" .. OrigDate .. "." .. " ";				-- in parentheses
			else]]	
				Date = " (" .. Date .. ")" .. OrigDate .. sepc .. " ";				-- in parentheses
			--end	
		else																	-- neither of authors and editors set
			if (string.sub(tcommon, -1, -1) == sepc) then						-- if the last character of tcommon is sepc
                if is_dstu then
                    Date = ", " .. Date .. OrigDate;	
                else    
				    Date = " " .. Date .. OrigDate;									-- Date does not begin with sepc
                end
			else
				Date = sepc .. " " .. Date .. OrigDate;							-- Date begins with sepc
			end
		end
	end
    if utilities.is_set(Authors) then
        if utilities.is_set(Coauthors) then
            if is_dstu or NameListStyle == 'vanc' then
                Authors = Authors .. cfg.presentation['sep_nl_vanc_dstu'] .. " " .. Coauthors
            else    
                Authors = Authors .. A['AuthorSeparator'] .. " " .. Coauthors
            end    
        end
        if (not utilities.is_set (Date)) then									-- when date is set it's in parentheses; no Authors termination
        	if is_dstu then
        		Authors = terminate_name_list (Authors, ".");	
        	else
				Authors = terminate_name_list (Authors, sepc);						-- when no date, terminate with 0 or 1 sepc and a space
			end
		end
        if utilities.is_set(Editors) then
            local in_text = '';
			local post_text = '';
			if utilities.is_set (Chapter) --[[and 0 == #c]] then
				in_text = cfg.messages['in'] .. ' ';
				if not use_uppercase then
					in_text = in_text:ulower();									-- lowercase for cs2
				end
			end
			if EditorCount <= 1 then
				post_text = ' (' .. cfg.messages['editor'] .. ')';				-- be consistent with no-author, no-date case
			else
				post_text = ' (' .. cfg.messages['editors'] .. ')';
			end
			Editors = terminate_name_list (in_text .. Editors .. post_text, sepc);	-- terminate with 0 or 1 sepc and a space
        end
        text = safe_join( {Authors, Date, Chapter, Place, Editors, tcommon, pgtext, idcommon }, sepc );
    elseif utilities.is_set(Editors) then
        if utilities.is_set(Date) then
            if EditorCount <= 1 then
                Editors = Editors .. ", " .. cfg.messages['editor'];
            else
                Editors = Editors .. ", " .. cfg.messages['editors'];
            end
        else
            if EditorCount <= 1 then
                Editors = Editors .. " (" .. cfg.messages['editor'] .. ")" .. sepc .. " "
            else
                Editors = Editors .. " (" .. cfg.messages['editors'] .. ")" .. sepc .. " "
            end
        end
        text = safe_join( {Editors, Date, Chapter, Place, tcommon, pgtext, idcommon}, sepc );
    else
        if config.CitationClass=="journal" and utilities.is_set(Periodical) then
            text = safe_join( {Chapter, Place, tcommon, pgtext, Date, idcommon}, sepc );
        else
            text = safe_join( {Chapter, Place, tcommon, Date, pgtext, idcommon}, sepc );
        end
    end
    
    --safe_join for dstu2006
   --[[ if is_dstu then (поки не задіяний код, закоментував)
    	local dstucommon2 = safe_join( {Authors, Editors, Others}, ',', sepc);
    	local dstucommon;
    	if utilities.is_set(dstucommon2) then
    		dstucommon2 = cfg.presentation['sep_sp_dstu2006'] .. ' ' .. dstucommon2;
    		dstucommon = safe_join( {Chapter, Title, Conference, dstucommon2}, cfg.presentation['sep_dsp_dstu2006'], sepc);
    	else	
    		dstucommon = safe_join( {Chapter, Title, Conference}, cfg.presentation['sep_dsp_dstu2006'], sepc);
    	end
    	if utilities.is_set(Language) then
    		dstucommon = dstucommon .. Language;
    	end	
    	local dstucommon3 = safe_join( {Publisher, Date}, ',');
		tcommon = safe_join( {dstucommon, Edition, Place, Publisher, Agency, Date, Volume, Issue, pgtext, Series, Position, idcommon}, sepc);
		--text = tcommon;
    end]]
    
    if utilities.is_set(PostScript) and PostScript ~= sepc then
        text = safe_join( {text, sepc}, sepc );  --Deals with italics, spaces, etc.
        if '.' == sepc then														-- remove final seperator if present
			text = text:gsub ('%' .. sepc .. '$', '');							-- dot must be escaped here
		else
			text = mw.ustring.gsub (text, sepc .. '$', '');						-- using ustring for non-dot sepc (likely a non-Latin character)
		end
    end    
    
    text = safe_join( {text, PostScript}, sepc );

    -- Now enclose the whole thing in a <span/> element
    if not utilities.is_set(Year) then
        if utilities.is_set(DateIn) then
            Year = select_year( DateIn );
        elseif utilities.is_set(PublicationDate) then
            Year = select_year( PublicationDate );
        end
    end
    
    local options = {};
    
    options.class = cite_class_attribute_make (config.CitationClass, Mode);
    
	local Ref = A['Ref'];
    
    if utilities.is_set(Ref) and Ref:lower() ~= "none" then
        local id = Ref
        if ( "harv" == Ref ) then
            local names = {} --table of last names & year
            if utilities.is_set(Authors) then
                for i,v in ipairs(a) do 
                    names[i] = v.last 
                    if i == 4 then break end
                end
            elseif utilities.is_set(Editors) then
                for i,v in ipairs(e) do 
                    names[i] = v.last 
                    if i == 4 then break end                
                end
            end
            names[ #names + 1 ] = Year;
            id = anchor_id(names)
        end
        options.id = id;
    end   
    
    if string.len(text:gsub("%b<>","")) <= 2 then
        z.error_categories = {};
        z.message_tail = {};
        OCinSoutput = nil;														-- blank the metadata string
		text = '';																-- blank the the citation
        utilities.set_message('err_empty_citation');
    end
    
    local render_t = {};														-- here we collect the final bits for concatenation into the rendered citation
    
    if utilities.is_set(options.id) then 
        table.insert (render_t, utilities.substitute (cfg.presentation['cite-id'], {mw.uri.anchorEncode(options.id), mw.text.nowiki(options.class), text}));
    else
        table.insert (render_t, utilities.substitute (cfg.presentation['cite'], {mw.text.nowiki(options.class), text}));
    end        

    local empty_span = '<span style="display:none;">&nbsp;</span>';
    
    -- Note: Using display: none on then COinS span breaks some clients.
    if OCinSoutput then
    	local OCinS = '<span title="' .. OCinSoutput .. '" class="Z3988">' .. empty_span .. '</span>';
    	text = text .. OCinS;
    end
    
    local template_name = ('citation' == config.CitationClass) and 'citation' or 'cite ' .. (cfg.citation_class_map_t[config.CitationClass] or config.CitationClass);
	local template_link = '[[Шаблон:' .. template_name .. '|' .. template_name .. ']]';
	local msg_prefix = '<code class="cs1-code">{{' .. template_link .. '}}</code>: ';
	
	if #z.message_tail ~= 0 then
		mw.addWarning (utilities.substitute (cfg.messages.warning_msg_e, template_link));
		
		table.insert (render_t, ' ');											-- insert a space between citation and its error messages
        table.sort (z.message_tail);
    	
    	local hidden = true;													-- presume that the only error messages emited by this template are hidden
		for _, v in ipairs (z.message_tail) do									-- spin through the list of error messages
			if v:find ('cs1-visible-error', 1, true) then						-- look for the visible error class name
				hidden = false;													-- found one; so don't hide the error message prefix
				break;															-- and done because no need to look further
			end
		end
    	
        z.message_tail[1] = table.concat ({utilities.error_comment (msg_prefix, hidden), z.message_tail[1]});	-- add error message prefix to first error message to prevent extraneous punctuation
		table.insert (render_t, table.concat (z.message_tail, '; '));			-- make a big string of error messages and add it to the rendering
    end
    
    if #z.maintaince_categories ~= 0 then
    	mw.addWarning (utilities.substitute (cfg.messages.warning_msg_m, template_link));
    	
    	table.sort (z.maintaince_categories);											-- sort the maintenance messages list
    	
    	local maint_msgs_t = {};
    	
    	if 0 == #z.message_tail then											-- if no error messages
			table.insert (maint_msgs_t, msg_prefix);							-- insert message prefix in maint message livery
		end
    	
    	for _, v in ipairs( z.maintaince_categories ) do
    		-- append maintenance categories
			table.insert (maint_msgs_t, 										-- assemble new maint message and add it to the maint_msgs_t table
				table.concat ({v, ' (', utilities.substitute (cfg.messages[':cat wikilink'], v), ')'})
				);
		end
		table.insert (render_t, utilities.substitute (cfg.presentation['hidden-maint'], table.concat (maint_msgs_t, ' ')));	-- wrap the group of maint messages with proper presentation and save
    end
    
    if not no_tracking_cats then
		local sort_key;
		local cat_wikilink = 'cat wikilink';
		if cfg.enable_sort_keys then											-- when namespace sort keys enabled
			local namespace_number = mw.title.getCurrentTitle().namespace;		-- get namespace number for this wikitext
			sort_key = (0 ~= namespace_number and (cfg.name_space_sort_keys[namespace_number] or cfg.name_space_sort_keys.other)) or nil;	-- get sort key character; nil for mainspace
			cat_wikilink = (not sort_key and 'cat wikilink') or 'cat wikilink sk';	-- make <cfg.messages> key
		end
		
        for _, v in ipairs( z.error_categories ) do										-- append error categories
            table.insert (render_t, utilities.substitute (cfg.messages[cat_wikilink], {v, sort_key}));
        end
        for _, v in ipairs (z.maintaince_categories) do									-- append maintenance categories
			table.insert (render_t, utilities.substitute (cfg.messages[cat_wikilink], {v, sort_key}));
        end
		for _, v in ipairs (z.properties_cats) do									-- append properties categories
			table.insert (render_t, utilities.substitute (cfg.messages['cat wikilink'], v));
		end
    end
    
    return table.concat (render_t);												-- make a big string and done
end

--[[--------------------------< V A L I D A T E >--------------------------------------------------------------

Looks for a parameter's name in one of several whitelists.

Parameters in the whitelist can have three values:
	true - active, supported parameters
	false - deprecated, supported parameters
	nil - unsupported parameters
	
]]

local function validate(name, cite_class, empty)
    local name = tostring (name);
	local enum_name;															-- parameter name with enumerator (if any) replaced with '#'
	local state;
	local function state_test (state, name)										-- local function to do testing of state values
		if true == state then return true; end									-- valid actively supported parameter
		if false == state then
			if empty then return nil; end										-- empty deprecated parameters are treated as unknowns
			deprecated_parameter (name);										-- parameter is deprecated but still supported
			return true;
		end
		if 'tracked' == state then
			local base_name = name:gsub ('%d', '');								-- strip enumerators from parameter names that have them to get the base name
			utilities.add_prop_cat ('tracked-param', {base_name}, base_name);	-- add a properties category; <base_name> modifies <key>
			return true;
		end
		return nil;
	end
	
	if name:find ('#') then														-- # is a cs1|2 reserved character so parameters with # not permitted
		return nil;
	end
	
																				-- replace wnumerator digit(s) with # (|last25= becomes |last#=) (mw.ustring because non-Western 'local' digits)
	enum_name = mw.ustring.gsub (name, '%d+$', '#');							-- where enumerator is last charaters in parameter name (these to protect |s2cid=)
	enum_name = mw.ustring.gsub (enum_name, '%d+([%-l])', '#%1');				-- where enumerator is in the middle of the parameter name; |author#link= is the oddity
    
   --[[if 'document' == cite_class then											-- special case for {{cite document}}
		state = whitelist.document_parameters_t[enum_name];						-- this list holds enumerated and nonenumerated parameters
		if true == state_test (state, name) then return true; end
		
		return false;
	end (поки не використовується)]]

	if utilities.in_array (cite_class, whitelist.preprint_template_list_t) then	-- limited parameter sets allowed for these templates
		state = whitelist.limited_parameters_t[enum_name];						-- this list holds enumerated and nonenumerated parameters
		if true == state_test (state, name) then return true; end

		state = whitelist.preprint_arguments_t[cite_class][name];				-- look in the parameter-list for the template identified by cite_class
		if true == state_test (state, name) then return true; end

		return false;															-- not supported because not found or name is set to nil
	end																			-- end limited parameter-set templates

	if utilities.in_array (cite_class, whitelist.unique_param_template_list_t) then 	-- template-specific parameters for templates that accept parameters from the basic argument list
		state = whitelist.unique_arguments_t[cite_class][name];					-- look in the template-specific parameter-lists for the template identified by cite_class
		if true == state_test (state, name) then return true; end
	end																		-- if here, fall into general validation

	state = whitelist.common_parameters_t[enum_name];							-- all other templates; all normal parameters allowed; this list holds enumerated and nonenumerated parameters
	if true == state_test (state, name) then return true; end

	return false;																-- not supported because not found or name is set to nil
end

--[[--------------------------< C I T A T I O N >--------------------------------------------------------------

This is used by templates such as {{cite book}} to create the actual citation text.

]]
local function citation(frame)

	local config = {};															-- table to store parameters from the module {{#invoke:}}
	for k, v in pairs( frame.args ) do											-- get parameters from the {{#invoke}} frame
		config[k] = v;
	--	args[k] = v;															-- crude debug support that allows us to render a citation from module {{#invoke:}}; skips parameter validation; TODO: keep?
	end	

																			-- i18n: set the name that your wiki uses to identify sandbox subpages from sandbox template invoke (or can be set here)
    local sandbox = ((config.SandboxPath and '' ~= config.SandboxPath) and config.SandboxPath) or '/пісочниця';	-- sandbox path from {{#invoke:Citation/CS1/sandbox|citation|SandboxPath=/...}}
    is_sandbox = nil ~= string.find (frame:getTitle(), sandbox, 1, true);		-- is this invoke the sandbox module?
    sandbox = is_sandbox and sandbox or '';										-- use i18n sandbox to load sandbox modules when this module is the sandox; live modules else
                                                                        

    local pframe = frame:getParent()
    local styles;

    cfg = mw.loadData ('Module:Citation/CS1/Configuration' .. sandbox);			-- load sandbox versions of support modules when {{#invoke:Citation/CS1/sandbox|...}}; live modules else
	whitelist = mw.loadData ('Module:Citation/CS1/Whitelist' .. sandbox);
	utilities = require ('Module:Citation/CS1/Utilities' .. sandbox);
--	validation = require ('Module:Citation/CS1/Date_validation' .. sandbox); (додано буде в наступних оновленнях)
	identifiers = require ('Module:Citation/CS1/Identifiers' .. sandbox);
	metadata = require ('Module:Citation/CS1/COinS' .. sandbox);
	styles = 'Module:Citation/CS1' .. sandbox .. '/styles.css';

    utilities.set_selected_modules (cfg);										-- so that functions in Utilities can see the selected cfg tables
--    validation.set_selected_modules (cfg, utilities);							-- so that functions in Date validataion can see selected cfg tables and the selected Utilities module (додано буде в наступних оновленнях)
    identifiers.set_selected_modules (cfg, utilities);							-- so that functions in Identifiers can see the selected cfg tables and selected Utilities module
    metadata.set_selected_modules (cfg, utilities);								-- so that functions in COinS can see the selected cfg tables and selected Utilities module
    
    z = utilities.z;
    
    local args = {};															-- table where we store all of the template's arguments
	local suggestions = {};														-- table where we store suggestions if we need to loadData them
	local error_text;															-- used as a flag
    
    local capture;																-- the single supported capture when matching unknown parameters using patterns
	local empty_unknowns = {};													-- sequence table to hold empty unknown params for error message listing
    for k, v in pairs( pframe.args ) do											-- get parameters from the parent (template) frame
		v = mw.ustring.gsub (v, '^%s*(.-)%s*$', '%1');							-- trim leading/trailing whitespace; when v is only whitespace, becomes empty string
		if v ~= '' then
            if ('string' == type (k)) then
				k = mw.ustring.gsub (k, '%d', cfg.date_names.local_digits);		-- for enumerated parameters, translate 'local' digits to Western 0-9
			end
            if not validate( k, config.CitationClass ) then            
                if type (k) ~= 'string' then									-- exclude empty numbered parameters
					if v:match("%S+") ~= nil then
						error_text = utilities.set_message ('err_text_ignored', {v});
					end
				elseif validate (k:ulower(), config.CitationClass) then 
					error_text = utilities.set_message ('err_parameter_ignored_suggest', {k, k:ulower()});	-- suggest the lowercase version of the parameter
				else
					if nil == suggestions.suggestions then						-- if this table is nil then we need to load it
						suggestions = mw.loadData ('Module:Citation/CS1/Suggestions' .. sandbox);	--load sandbox version of suggestion module when {{#invoke:Citation/CS1/sandbox|...}}; live module else
					end
					for pattern, param in pairs (suggestions.patterns) do		-- loop through the patterns to see if we can suggest a proper parameter
						capture = k:match (pattern);							-- the whole match if no capture in pattern else the capture if a match
						if capture then											-- if the pattern matches 
							param = utilities.substitute (param, capture);		-- add the capture to the suggested parameter (typically the enumerator)
							if validate (param, config.CitationClass) then		-- validate the suggestion to make sure that the suggestion is supported by this template (necessary for limited parameter lists)
								error_text = utilities.set_message ('err_parameter_ignored_suggest', {k, param});	-- set the suggestion error message
							else
								error_text = utilities.set_message ('err_parameter_ignored', {k});	-- suggested param not supported by this template
								v = '';											-- unset
							end
						end
					end
					if not utilities.is_set (error_text) then					-- couldn't match with a pattern, is there an explicit suggestion?						
						if (suggestions.suggestions[ k:ulower() ] ~= nil) and validate (suggestions.suggestions[ k:ulower() ], config.CitationClass) then
							utilities.set_message ('err_parameter_ignored_suggest', {k, suggestions.suggestions[ k:ulower() ]});
						else
							utilities.set_message ('err_parameter_ignored', {k});
							v = '';												-- unset value assigned to unrecognized parameters (this for the limited parameter lists)
						end
					end
				end				  
			end

			args[k] = v;														-- save this parameter and its value

		elseif not utilities.is_set (v) then									-- for empty parameters
			if not validate (k, config.CitationClass, true) then				-- is this empty parameter a valid parameter
				k = ('' == k) and '(пустий рядок)' or k;						-- when k is empty string (or was space(s) trimmed to empty string), replace with descriptive text
				table.insert (empty_unknowns, utilities.wrap_style ('parameter', k));	-- format for error message and add to the list
			end
																				-- crude debug support that allows us to render a citation from module {{#invoke:}} TODO: keep?
	--	elseif args[k] ~= nil or (k == 'postscript') then						-- when args[k] has a value from {{#invoke}} frame (we don't normally do that)
	--		args[k] = v;														-- overwrite args[k] with empty string from pframe.args[k] (template frame); v is empty string here
		end																		-- not sure about the postscript bit; that gets handled in parameter validation; historical artifact?
	end 
    
    if 0 ~= #empty_unknowns then												-- create empty unknown error message
		utilities.set_message ('err_param_unknown_empty', {
			1 == #empty_unknowns and '' or 'и',
			utilities.make_sep_list (#empty_unknowns, empty_unknowns),
			1 == #empty_unknowns and 'ий' or 'і'
			});
	end
    
    return table.concat ({
    	frame:extensionTag ('templatestyles', '', {src=styles}),
		citation0( config, args) 
    	});
end

--[[--------------------------< E X P O R T E D   F U N C T I O N S >------------------------------------------
]]

return {citation = citation};