Модуль:Citation/CS1

Матеріал з Вікіпедії — вільної енциклопедії.
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{{i}} Документація модуля[перегляд] [редагувати] [історія] [очистити кеш]


{{Модуль:Citation/CS1}} (обг. · викор. · ред.)

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

Цей модуль містить код, запозичений з модуля «Citation/CS1» англійської Вікіпедії.

Переклад
-- Include translation message hooks, ID and error handling configuration settings.
-- Note that require has tested to be significantly faster than loadData for this 
-- usage.  This might be a side effect of the unnecessary cloning described 
-- in bugzilla 47300.
local cfg = require( 'Module:Citation/CS1/Configuration' );

-- Contains a list of all recognized parameters
local whitelist = mw.loadData( 'Module:Citation/CS1/Whitelist' );
local utilities = require ('Module:Citation/CS1/Utilities');
local metadata = require ('Module:Citation/CS1/COinS');
local z = {};

-- First set variable or nil if none
function first_set(...)
    local list = {...};
    for _, var in pairs(list) do
        if utilities.is_set( var ) then
            return var;
        end
    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
function wrap( key, str )
    if not utilities.is_set( str ) then
        return "";
    elseif utilities.in_array( key, { 'italic-title', 'trans-italic-title' } ) then
        str = safe_for_italics( str );
    end
    return utilities.substitute( cfg.messages[key], {str} );
end

--utilities.substitute template {{ref-lang}} if possible
local refTemplateSupportedLangs = 
{
	[2] = 
	{
		'uk', 'en', 'ru', 'be', 'pl', 'es', 'fr', 'de', 'ar', 'it', 'cs', 
		'ab', 'af', 'an', 'az', 'ba', 'bg', 'bl', 'bn', 'br', 'bs', 'ca', 
		'ce', 'co', 'cu', 'cv', 'cy', 'cz', 'da', 'et', 'fa', 'fi', 'fo', 
		'fy', 'ga', 'eo', 'eu', 'gd', 'ge', 'gl', 'el', 'ha', 'he', 'hi', 
		'hr', 'hu', 'hy', 'id', 'ie', 'is', 'ja', 'ka', 'kk', 'kl', 'km', 
		'kn', 'ko', 'kv', 'ky', 'la', 'le', 'lt', 'lb', 'lv', 'md', 'me', 
		'mg', 'mi', 'mk', 'mn', 'mo', 'ms', 'mt', 'ne', 'nl', 'no', 'oc', 
		'os', 'pt', 'rm', 'ro', 'sa', 'sh', 'sk', 'sl', 'sq', 'sr', 'sv', 
		'sw', 'te', 'ta', 'tg', 'th', 'tk', 'tl', 'tr', 'tt', 'ur', 'uz', 
		'vi', 'xal', 'yi', 'zh'
	}, 
	[3] = 
	{
		'crh', 'rue', 'arz', 'chu', 'dsb', 'gag', 'grc', 'hsb', 'kaa', 
		'kdr', 'krl', 'ltg', 'mhr', 'myv', 'non', 'orv', 'pap', 'pnt', 
		'rmy', 'sah', 'sla', 'szl', 'udm', 'lld', 'uum'
	}, 
	[4] = {}, 
	[5] = {'en-US'}, 
	[6] = {'uk-old', 'old-ru', 'ru-dor'}, 
	[7] = {'bat-smg'}
}

function SubstLangTemplateIfPossible(lang_code, is_dstu)
	if #lang_code>=2 and #lang_code<=7 and utilities.in_array(lang_code, refTemplateSupportedLangs[#lang_code]) then
		if is_dstu then
			return '{{lg|'..lang_code..'}}'
		else
			return '{{ref-'..lang_code..'}}'
		end
	else
		return nil
	end
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'
}

function ParseDateIfPossible(dateString)
	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 day and month then
		local month_int = utilities.in_array(month, englishMonthNames)
		if not month_int then return dateString end
		local day_int = tonumber(day)
		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.
]]
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 list == nil then
                error( cfg.messages['unknown_argument_map'] );
            elseif type( list ) == 'string' then
                v, origin[k] = args[list], list;
            else
                v, origin[k] = select_one( args, list, 'redundant_parameters' );
                if origin[k] == nil then
                    origin[k] = '';   --Empty string, not nil;
                end
            end
            
            if v == nil then
                v = cfg.defaults[k] or "";
                origin[k] = '';   --Empty string, not nil;
            end
            
            tbl = rawset( tbl, k, v );
            return v;
        end,
    });
end

-- Checks that parameter name is valid using the whitelist
function validate( name )
    name = tostring( name );
    
    -- Normal arguments
    if whitelist.basic_arguments[ name ] then
        return true;
    end
    
    -- Arguments with numbers in them
    name = name:gsub( "%d+", "#" );
    if whitelist.numbered_arguments[ name ] then
        return true;
    end
    
    -- Not found, argument not supported.
    return false
end

-- Formats a wiki style external link
function external_link_id(options)
    local url_string = options.id;
    if options.encode == true or options.encode == nil then
        url_string = mw.uri.encode( url_string );
    end
    return mw.ustring.format( '[[%s|%s]]%s[%s%s%s %s]',
        options.link, options.label, options.separator or "&nbsp;",
        options.prefix, url_string, options.suffix or "",
        mw.text.nowiki(options.id)
    );
end

-- Formats a wiki style internal link
function internal_link_id(options)
    return mw.ustring.format( '[[%s|%s]]%s[[%s%s%s|%s]]',
        options.link, options.label, options.separator or "&nbsp;",
        options.prefix, options.id, options.suffix or "",
        mw.text.nowiki(options.id)
    );
end

-- Format an external link with error checking
function external_link( URL, label, source )
    if not utilities.is_set( label ) then
        label = URL;
        if utilities.is_set( source ) then
            utilities.set_message( '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( 'bad_url', {}, false, " " );
    end
    return table.concat({ "[", URL, " ", safe_for_url( label ), "]"});
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

--[[--------------------------< 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

-- Formats a link to Amazon
function amazon(id, domain)
    if not utilities.is_set(domain) then 
        domain = "com"
    elseif ( "jp" == domain or "uk" == domain ) then
        domain = "co." .. domain
    end
    local handler = cfg.id_handlers['ASIN'];
    return external_link_id({link = handler.link,
        label=handler.label , prefix="//www.amazon."..domain.."/dp/",id=id,
        encode=handler.encode, separator = handler.separator})
end

-- Formats a DOI and checks for DOI errors.
function doi(id, inactive)
    local handler = cfg.id_handlers['DOI'];
    
    local text;
    if utilities.is_set(inactive) then
        text = "[[" .. handler.link .. "|" .. handler.label .. "]]:" .. id;
        table.insert( z.error_categories, "Pages with DOIs inactive since " .. select_year(inactive) );        
        inactive = " (" .. cfg.messages['inactive'] .. " " .. inactive .. ")" 
    else 
        text = external_link_id({link = handler.link, label = handler.label,
            prefix=handler.prefix,id=id,separator=handler.separator, encode=handler.encode})
        inactive = "" 
    end
    if ( string.sub(id,1,3) ~= "10." ) then      
        utilities.set_message( 'bad_doi' );
    end
    return text .. inactive 
end

-- Formats an OpenLibrary link, and checks for associated errors.
function openlibrary(id)
    local code = id:sub(-1,-1)
    local handler = cfg.id_handlers['OL'];
    if ( code == "A" ) then
        return external_link_id({link=handler.link, label=handler.label,
            prefix="http://openlibrary.org/authors/OL",id=id, separator=handler.separator,
            encode = handler.encode})
    elseif ( code == "M" ) then
        return external_link_id({link=handler.link, label=handler.label,
            prefix="http://openlibrary.org/books/OL",id=id, separator=handler.separator,
            encode = handler.encode})
    elseif ( code == "W" ) then
        return external_link_id({link=handler.link, label=handler.label,
            prefix= "http://openlibrary.org/works/OL",id=id, separator=handler.separator,
            encode = handler.encode})
    else
    	utilities.set_message( 'bad_ol' );
        return external_link_id({link=handler.link, label=handler.label,
            prefix= "http://openlibrary.org/OL",id=id, separator=handler.separator,
            encode = handler.encode});
    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.
]]
function check_url( url_str )
    -- Protocol-relative or URL scheme
    return url_str:sub(1,2) == "//" or url_str:match( "^[^/]*:" ) ~= nil;
end

-- Removes irrelevant text and dashes from ISBN number
-- Similar to that used for Special:BookSources
function clean_isbn( isbn_str )
    return isbn_str:gsub( "[^-0-9X]", "" );
end

-- Determines whether an ISBN string is valid
function check_isbn( isbn_str )
    isbn_str = clean_isbn( isbn_str ):gsub( "-", "" );
    local len = isbn_str:len();
 
    if len ~= 10 and len ~= 13 then
        return false;
    end
 
    local temp = 0;
    if len == 10 then
        if isbn_str:match( "^%d*X?$" ) == nil then return false; end
        isbn_str = { isbn_str:byte(1, len) };
        for i, v in ipairs( isbn_str ) do
            if v == string.byte( "X" ) then
                temp = temp + 10*( 11 - i );
            else
                temp = temp + tonumber( string.char(v) )*(11-i);
            end
        end
        return temp % 11 == 0;
    else
        if isbn_str:match( "^%d*$" ) == nil then return false; end
        isbn_str = { isbn_str:byte(1, len) };
        for i, v in ipairs( isbn_str ) do
            temp = temp + (3 - 2*(i % 2)) * tonumber( string.char(v) );
        end
        return temp % 10 == 0;
    end
end

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

-- Escape sequences for content that will be used for URL descriptions
function safe_for_url( str )
    if str:match( "%[%[.-%]%]" ) ~= nil then 
        utilities.set_message( 'wikilink_in_url', {});
    end
    
    return str:gsub( '[%[%]\n]', {    
        ['['] = '&#91;',
        [']'] = '&#93;',
        ['\n'] = ' ' } );
end

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

-- Protects a string that will be wrapped in wiki italic markup '' ... ''
function safe_for_italics( str )
    --[[ Note: We can not use <i> for italics, as the expected behavior for
    italics specified by ''...'' in the title is that they will be inverted
    (i.e. unitalicized) in the resulting references.  In addition, <i> and ''
    tend to interact poorly under Mediawiki's HTML tidy. ]]
    
    if not utilities.is_set(str) then
        return str;
    else
        if str:sub(1,1) == "'" then str = "<span></span>" .. str; end
        if str:sub(-1,-1) == "'" then str = str .. "<span></span>"; end
        
        -- Remove newlines as they break italics.
        return str:gsub( '\n', ' ' );
    end
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 = wrap ('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 = wrap (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 ('trans_missing_title', {'periodical'});
		end
	end

	return periodical;
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.
]]
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]+(.+)$');								-- get generational suffix
		end
	end
	if utilities.is_set (suffix) then
		if not is_suffix (suffix) then
			add_vanc_error (cfg.err_msg_supl.suffix, position);
			return false;														-- not a name with an appropriate suffix
		end
	end
	if nil == mw.ustring.find (last, "^[A-Za-z\195\128-\195\150\195\152-\195\182\195\184-\198\191\199\132-\201\143%-%s%']*$") 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%-%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)
	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, 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 suffix

	while names[i] do															-- loop through the table
		if 1 < i and names[i]:match ('[%dJS][%drndth]+%.?$') then				-- if not the first name, and looks like a suffix (may have trailing dot)
			names[i] = names[i]:gsub ('%.', '');								-- remove terminal dot if present
			if is_suffix (names[i]) then										-- if a legitimate suffix
				table.insert (initials, ' ' .. names[i]);						-- add a separator space, insert at end of initials table
				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, mw.ustring.sub(names[i], 1, 1));			-- insert the initial at end of initials table
		end
		i = i + 1;																-- bump the counter
	end
			
	return table.concat(initials)												-- 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) 
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;
                    	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
    
    -- if necessary wrap result in <span> tag to format in Small Caps
    if ( "scap" == format ) then result = 
        '<span class="smallcaps" style="font-variant:small-caps">' .. result .. '</span>';
    end 
    return result, count
end

-- Generates a CITEREF anchor ID.
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.

]]
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 = select_one ( args, cfg.aliases[list_name .. '-Last'], 'redundant_parameters', i );		-- search through args for name components beginning at 1
		first, first_alias = select_one ( args, cfg.aliases[list_name .. '-First'], 'redundant_parameters', i );
		link = select_one ( args, cfg.aliases[list_name .. '-Link'], 'redundant_parameters', i );
		mask = select_one ( args, cfg.aliases[list_name .. '-Mask'], '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 'citation' == cite_class then
			utilities.set_message ('maint_postscript');
		end
		postscript = '';
	end
	
	return sep, postscript
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

-- Populates ID table from arguments using configuration settings
function extract_ids( args )
    local id_list = {};
    for k, v in pairs( cfg.id_handlers ) do    
        v = select_one( args, v.parameters, 'redundant_parameters' );
        if utilities.is_set(v) then id_list[k] = v; end
    end
    return id_list;
end

-- Takes a table of IDs and turns it into a table of formatted ID outputs.
function build_id_list( id_list, options )
    local new_list, handler = {};
    
    function fallback(k) return { __index = function(t,i) return cfg.id_handlers[k][i] end } end;
    
    for k, v in pairs( id_list ) do
        -- fallback to read-only cfg
        handler = setmetatable( { ['id'] = v }, fallback(k) );
        
        if handler.mode == 'external' then
            table.insert( new_list, {handler.label, external_link_id( handler ) } );
        elseif handler.mode == 'internal' then
            table.insert( new_list, {handler.label, internal_link_id( handler ) } );
        elseif handler.mode ~= 'manual' then
            error( cfg.messages['unknown_ID_mode'] );
        elseif k == 'DOI' then
            table.insert( new_list, {handler.label, doi( v, options.DoiBroken ) } );
        elseif k == 'ASIN' then
            table.insert( new_list, {handler.label, amazon( v, options.ASINTLD ) } ); 
        elseif k == 'OL' then
            table.insert( new_list, {handler.label, openlibrary( v ) } );
        elseif k == 'ISBN' then
            local ISBN = internal_link_id( handler );
            if not check_isbn( v ) and not utilities.is_set(options.IgnoreISBN) then
                utilities.set_message( 'bad_isbn', {}, false, " ", "" );
            end
            table.insert( new_list, {handler.label, ISBN } );                
        else
            error( cfg.messages['unknown_manual_ID'] );
        end
    end
    
    function comp( a, b )
        return a[1] < b[1];
    end
    
    table.sort( new_list, comp );
    for k, v in ipairs( new_list ) do
        new_list[k] = v[2];
    end
    
    return new_list;
end
  
-- Chooses one matching parameter from a list of parameters to consider
-- Generates an error if more than one match is present.
function select_one( args, possible, error_condition, index )
    local value = nil;
    local selected = '';
    local error_list = {};
    
    if index ~= nil then index = tostring(index); end
    
    -- Handle special case of "#" replaced by empty string
    if index == '1' then
        for _, v in ipairs( possible ) do
            v = v:gsub( "#", "" );
            if utilities.is_set(args[v]) then
                if value ~= nil and selected ~= v then
                    table.insert( error_list, v );
                else
                    value = args[v];
                    selected = v;
                end
            end
        end        
    end
    
    for _, v in ipairs( possible ) do
        if index ~= nil then
            v = v:gsub( "#", index );
        end
        if utilities.is_set(args[v]) then
            if value ~= nil and selected ~=  v then
                table.insert( error_list, v );
            else
                value = args[v];
                selected = v;
            end
        end
    end
    
    if #error_list > 0 then
        local error_str = "";
        for _, k in ipairs( error_list ) do
            if error_str ~= "" then error_str = error_str .. cfg.messages['parameter-separator'] end
            error_str = error_str .. wrap( 'parameter', k );
        end
        if #error_list > 1 then
            error_str = error_str .. cfg.messages['parameter-final-separator'];
        else
            error_str = error_str .. cfg.messages['parameter-pair-separator'];
        end
        error_str = error_str .. wrap( 'parameter', selected );
        utilities.set_message( error_condition, {error_str});
    end
    
    return value, selected;
end

-- COinS metadata (see <http://ocoins.info/>) allows automated tools to parse
-- the citation information.
function COinS(data)
    if 'table' ~= type(data) or nil == next(data) then
        return '';
    end
    
    local ctx_ver = "Z39.88-2004";
    
    -- treat table strictly as an array with only set values.
    local OCinSoutput = setmetatable( {}, {
        __newindex = function(self, key, value)
            if utilities.is_set(value) then
                rawset( self, #self+1, table.concat{ key, '=', mw.uri.encode( remove_wiki_link( value ) ) } );
            end
        end
    });
    
    if utilities.is_set(data.Chapter) then
        OCinSoutput.rft_val_fmt = "info:ofi/fmt:kev:mtx:book";
        OCinSoutput["rft.genre"] = "bookitem";
        OCinSoutput["rft.btitle"] = data.Chapter;
        OCinSoutput["rft.atitle"] = data.Title;
    elseif utilities.is_set(data.Periodical) then
        OCinSoutput.rft_val_fmt = "info:ofi/fmt:kev:mtx:journal";
        OCinSoutput["rft.genre"] = "article";
        OCinSoutput["rft.jtitle"] = data.Periodical;
        OCinSoutput["rft.atitle"] = data.Title;
    else
        OCinSoutput.rft_val_fmt = "info:ofi/fmt:kev:mtx:book";
        OCinSoutput["rft.genre"] = "book"
        OCinSoutput["rft.btitle"] = data.Title;
    end
    
    OCinSoutput["rft.place"] = data.PublicationPlace;
    OCinSoutput["rft.date"] = data.Date;
    OCinSoutput["rft.series"] = data.Series;
    OCinSoutput["rft.volume"] = data.Volume;
    OCinSoutput["rft.issue"] = data.Issue;
    OCinSoutput["rft.pages"] = data.Pages;
    OCinSoutput["rft.edition"] = data.Edition;
    OCinSoutput["rft.pub"] = data.PublisherName;
    
    for k, v in pairs( data.ID_list ) do
        local id, value = cfg.id_handlers[k].COinS;
        if k == 'ISBN' then value = clean_isbn( v ); else value = v; end
        if string.sub( id or "", 1, 4 ) == 'info' then
            OCinSoutput["rft_id"] = table.concat{ id, "/", v };
        else
            OCinSoutput[ id ] = value;
        end
    end
    
    local last, first;
    for k, v in ipairs( data.Authors ) do
        last, first = v.last, v.first;
        if k == 1 then
            if utilities.is_set(last) then
                OCinSoutput["rft.aulast"] = last;
            end
            if utilities.is_set(first) then 
                OCinSoutput["rft.aufirst"] = first;
            end
        end
        if utilities.is_set(last) and utilities.is_set(first) then
            OCinSoutput["rft.au"] = table.concat{ last, ", ", first };
        elseif utilities.is_set(last) then
            OCinSoutput["rft.au"] = last;
        end
    end
    
    OCinSoutput.rft_id = data.URL;
    OCinSoutput.rfr_id = table.concat{ "info:sid/", mw.site.server:match( "[^/]*$" ), ":", data.RawPage };
    OCinSoutput = setmetatable( OCinSoutput, nil );
    
    -- sort with version string always first, and combine.
    table.sort( OCinSoutput );
    table.insert( OCinSoutput, 1, "ctx_ver=" .. ctx_ver );  -- such as "Z39.88-2004"
    return table.concat(OCinSoutput, "&");
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 = select_one ( args, cfg.aliases[list_name .. '-Link'], 'redundant_parameters', i ) or v_link_table[i];
		mask = select_one ( args, cfg.aliases[list_name .. '-Mask'], '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 ('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

--[[
This is the main function foing the majority of the citation
formatting.
]]
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 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;

    local Year = A['Year'];
    local PublicationDate = A['PublicationDate'];
    local Date = A['Date'];
    local LayDate = A['LayDate'];
    ------------------------------------------------- Get title data
    local Title = A['Title'];
    local BookTitle = A['BookTitle'];
    local Conference = A['Conference'];
    local ScriptTitle = A['ScriptTitle'];
    local TransTitle = A['TransTitle'];
    local TitleNote = A['TitleNote'];
    local TitleLink = A['TitleLink'];
    
    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 Chapter = A['Chapter'];
    local ChapterLink = A['ChapterLink'];
    local Chapter_origin = A:ORIGIN ('Chapter');
    local ScriptChapter = A['ScriptChapter'];
    local ScriptChapter_origin = A:ORIGIN ('ScriptChapter');
    local TransChapter = A['TransChapter'];
    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 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 ''; (у планах, поки не реалізовано)
	--local Sheets = A['Sheets'] or ''; (у планах, поки не реалізовано)
	if config.CitationClass == "map" then
		if utilities.is_set (Chapter) then										--TODO: make a function for this and similar?
			utilities.set_message ('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']; (поки не реалізовано, потрібно переписувати код Chapter)

		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 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
    local ArchiveURL = A['ArchiveURL'];
    local UrlStatus = A['UrlStatus'];
    local URL = A['URL'];
    local URLorigin = A:ORIGIN('URL');
    local ChapterURL = A['ChapterURL'];
    local ChapterURLorigin = A:ORIGIN('ChapterURL');
    local ConferenceURL = A['ConferenceURL'];
    local ConferenceURLorigin = A:ORIGIN('ConferenceURL');
    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 ( config.CitationClass == "encyclopaedia" ) then
        if not utilities.is_set(Chapter) then
            if not utilities.is_set(Title) or utilities.is_set (ScriptTitle) then
                Title = Periodical;
                Periodical = '';
            else
                Chapter = Title;
                ScriptChapter= ScriptTitle;
                ScriptChapter_origin = A:ORIGIN('ScriptTitle');
                TransChapter = TransTitle;
                Title = '';
                ScriptTitle = '';
                TransTitle = '';
            end
        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 ('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 Series = A['Series'];
    local Volume = A['Volume'];
    local Issue = A['Issue'];
    local Position = '';
    local Page, Pages, At, page_type;
    
    Page = A['Page'];
    Pages = hyphen_to_dash( A['Pages'] );
    At = A['At'];
    
    if utilities.is_set(Page) then
        if utilities.is_set(At) then
            utilities.set_message('extra_pages');
            At = '';
        end
    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 SubscriptionRequired = A['SubscriptionRequired'];
    local Via = A['Via'];
    local AccessDate = A['AccessDate'];
    local ArchiveDate = A['ArchiveDate'];
    local Agency = A['Agency'];
    local DeadURL = A['DeadURL']
    local Language = A['Language'];
    local Format = A['Format'];
    local Ref = A['Ref'];
    
    local DoiBroken = A['DoiBroken'];
    local ID = A['ID'];
    local ASINTLD = A['ASINTLD'];
    local IgnoreISBN = A['IgnoreISBN'];

    local ID_list = extract_ids( args );
    
    local Quote = A['Quote'];
    local ScriptQuote = A['ScriptQuote'];
    local TransQuote = A['TransQuote'];
    local LayURL = A['LayURL'];
    local LaySource = A['LaySource'];
    local Transcript = A['Transcript'];
    local TranscriptURL = A['TranscriptURL'] 
    local TranscriptURLorigin = A:ORIGIN('TranscriptURL');
    local LastAuthorAmp = A['LastAuthorAmp'];
    local no_tracking_cats = A['NoTracking'];

    local this_page = mw.title.getCurrentTitle();  --Also used for COinS
    
    -- 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

    if ( config.CitationClass == "journal" ) then
        if not utilities.is_set(URL) and utilities.is_set(ID_list['PMC']) then
            local Embargo = A['Embargo'];
            if utilities.is_set(Embargo) then
                local lang = mw.getContentLanguage();
                local good1, result1, good2, result2;
                good1, result1 = pcall( lang.formatDate, lang, 'U', Embargo );
                good2, result2 = pcall( lang.formatDate, lang, 'U' );
                
                if good1 and good2 and tonumber( result1 ) < tonumber( result2 ) then 
                    URL = "http://www.ncbi.nlm.nih.gov/pmc/articles/PMC" .. ID_list['PMC'];
                    URLorigin = cfg.id_handlers['PMC'].parameters[1];
                end
            else
                URL = "http://www.ncbi.nlm.nih.gov/pmc/articles/PMC" .. ID_list['PMC'];
                URLorigin = cfg.id_handlers['PMC'].parameters[1];
            end
        end
    end

    -- At this point fields may be nil if they weren't specified in the template use.  We can use that fact.
    
    -- Account for the oddity that is {{cite conference}}, before generation of COinS data.
    if utilities.is_set(BookTitle) then
        Chapter = Title;
        ChapterLink = TitleLink;
        ChapterUrlAccess = UrlAccess;
        ScriptChapter = ScriptTitle;
        ScriptChapter_origin = A:ORIGIN('ScriptTitle');
        TransChapter = TransTitle;
        Title = BookTitle;
        TitleLink = '';
        ScriptTitle = '';
        TransTitle = '';
    end
    -- 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 ('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); ( поки не короктнео працює в нас через стару реалізацію 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
    
    -- COinS metadata (see <http://ocoins.info/>) for
    -- automated parsing of citation information.
    local OCinSoutput = COinS{
        ['Periodical'] = Periodical,
        ['Chapter'] = metadata.make_coins_title(Chapter, ScriptChapter),
        ['Title'] = metadata.make_coins_title (Title, ScriptTitle),
        ['PublicationPlace'] = PublicationPlace,
        ['Date'] = first_set(Date, Year, PublicationDate),
        ['Degree'] = Degree;													-- cite thesis only
        ['Series'] = Series,
        ['Volume'] = Volume,
        ['Issue'] = Issue,
        ['Pages'] = first_set(Page, Pages, At),
        ['Edition'] = Edition,
        ['PublisherName'] = PublisherName,
        ['URL'] = first_set( URL, ChapterURL ),
        ['Authors'] = a,
        ['ID_list'] = ID_list,
        ['RawPage'] = this_page.prefixedText,
    };

    if (utilities.is_set(Periodical) or utilities.is_set(ScriptPeriodical)) and not (utilities.is_set(Chapter) or utilities.is_set(ScriptChapter)) and (utilities.is_set(Title) or utilities.is_set(ScriptTitle)) then
        Chapter = Title;
        ChapterLink = TitleLink;
        ChapterUrlAccess = UrlAccess;
        ScriptChapter = ScriptTitle;
        ScriptChapter_origin = A:ORIGIN('ScriptTitle');
        TransChapter = TransTitle;
        Title = '';
        TitleLink = '';
        ScriptTitle = '';
        TransTitle = '';
    end

    -- 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 = nil,												        -- 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"]) or "") .. " ";
            control.format = first_set(A["AuthorFormat"], NameListStyle);
            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"]) or "") .. " ";
            control.format = first_set(A["EditorFormat"], NameListStyle);
            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.format = NameListStyle;

            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.format = NameListStyle;
        
            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
    
    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;
    
    if  not utilities.is_set(URL) and
        not utilities.is_set(ChapterURL) and
        not utilities.is_set(ArchiveURL) and
        not utilities.is_set(ConferenceURL) and
        not utilities.is_set(TranscriptURL) then
        
        -- Test if cite web is called without giving a URL
        if utilities.in_array (config.CitationClass, {"web", "podcast", "mailinglist"}) then
            utilities.set_message( 'cite_web_url', {});
        end
        
        -- Test if accessdate is given without giving a URL
        if utilities.is_set(AccessDate) then
            utilities.set_message( 'accessdate_missing_url', {});
            AccessDate = '';
        end
        
        -- Test if format is given without giving a URL
        if utilities.is_set(Format) then
            utilities.set_message( 'format_missing_url' );
        end
    end
    
    -- Test if citation has no title
    if  not utilities.is_set(Chapter) and
        not utilities.is_set(Title) and
        not utilities.is_set(Periodical) and
        not utilities.is_set(ScriptPeriodical) and
        not utilities.is_set(TransPeriodical) and
        not utilities.is_set(Conference) and
        not utilities.is_set(ScriptTitle) and
        not utilities.is_set(TransTitle) and
        not utilities.is_set(ScriptChapter) and
        not utilities.is_set(TransChapter) then
        utilities.set_message( 'citation_missing_title', {});
    end
    
    Format = utilities.is_set(Format) and " (" .. Format .. ")" or "";
    
    local OriginalURL = URL
    DeadURL = DeadURL:ulower();
    UrlStatus = UrlStatus:ulower();
    if utilities.is_set( ArchiveURL ) then
        if ( DeadURL == "yes" and UrlStatus ~= "live") then
            URL = ArchiveURL
            URLorigin = A:ORIGIN('ArchiveURL')
        end
    end
    
    local trans_qoute_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
    
    -- Format chapter / article title
    if utilities.is_set(Chapter) and utilities.is_set(ChapterLink) then 
        Chapter = "[[" .. ChapterLink .. "|" .. Chapter .. "]]";
    end
    if utilities.is_set(Periodical) and utilities.is_set(Title) then
        Chapter = wrap( 'italic-title', Chapter );
        Chapter = script_concatenate (Chapter, ScriptChapter, ScriptChapter_origin);
        TransChapter = wrap( trans_italic_title, TransChapter );
    else
        Chapter = wrap( 'quoted-title', Chapter );
        Chapter = script_concatenate (Chapter, ScriptChapter, ScriptChapter_origin);
        TransChapter = wrap( trans_quoted_title, TransChapter );
    end
    
    if utilities.is_set(TransChapter) then
        if not utilities.is_set(Chapter) then
            utilities.set_message( 'trans_missing_title', {'chapter'});
        else
            TransChapter = " " .. TransChapter;
        end
    end
    
    Chapter = Chapter .. TransChapter;
    
    
    if utilities.is_set(Chapter) then
        if not utilities.is_set(ChapterLink) then
            if utilities.is_set(ChapterURL) then
                Chapter = external_link( ChapterURL, Chapter, ChapterUrlAccess );
                if not utilities.is_set(URL) then
                    Chapter = Chapter .. Format;
                    Format = "";
                end
            elseif utilities.is_set(URL) then 
                Chapter = external_link( URL, Chapter ) .. Format;
                URL = "";
                Format = "";
            end            
        elseif utilities.is_set(ChapterURL) then
            Chapter = Chapter .. " " .. external_link( ChapterURL, nil, ChapterURLorigin, ChapterUrlAccess );
        end
        if 'map' == config.CitationClass and utilities.is_set (TitleType) then
			Chapter = Chapter .. ' ' .. TitleType;							-- map annotation here; not after title
		end
        Chapter = Chapter .. sepc .. " " -- with end-space
    elseif utilities.is_set(ChapterURL) then
        Chapter = " " .. external_link( ChapterURL, nil, ChapterURLorigin, ChapterUrlAccess ) .. sepc .. " ";
    end        
    
    -- Format main title.
    if utilities.is_set(TitleLink) and utilities.is_set(Title) then
        Title = "[[" .. TitleLink .. "|" .. Title .. "]]"
    end
    
    if utilities.is_set(Periodical) then
        Title = wrap( 'quoted-title', Title );
        Title = script_concatenate (Title, ScriptTitle, 'script-title');
        TransTitle = wrap( trans_quoted_title, TransTitle );
    elseif utilities.in_array(config.CitationClass, {"web","news","pressrelease"}) and
            not utilities.is_set(Chapter) then
        Title = wrap( 'quoted-title', Title );
        Title = script_concatenate (Title, ScriptTitle, 'script-title');
        TransTitle = wrap( trans_quoted_title, TransTitle );
    else
        Title = wrap( 'italic-title', Title );
        Title = script_concatenate (Title, ScriptTitle, 'script-title');
        TransTitle = wrap( trans_italic_title, TransTitle );
    end
    
    if utilities.is_set(TransTitle) then
        if not utilities.is_set(Title) then
            utilities.set_message( 'trans_missing_title', {'title'});
        else
            TransTitle = " " .. TransTitle;
        end
    end
    
    Title = Title .. TransTitle;
    
    if utilities.is_set(Title) then
        if not utilities.is_set(TitleLink) and utilities.is_set(URL) then 
            Title = external_link( URL, Title ) .. Format       
            URL = "";
            Format = "";
        end
    end
    
    if utilities.is_set(Place) then
        if use_uppercase then
            Place = " " .. wrap( 'written', Place ) .. sepc .. " ";
        else
            Place = " " .. utilities.substitute( cfg.messages['written']:ulower(), {Place} ) .. sepc .. " ";
        end
    end
    
    if utilities.is_set(Conference) then
        if utilities.is_set(ConferenceURL) then
            Conference = external_link( ConferenceURL, Conference );
        end
        Conference = " " .. Conference
    elseif utilities.is_set(ConferenceURL) then
        Conference = " " .. external_link( ConferenceURL, nil, ConferenceURLorigin );
    end
    
    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
    
    if utilities.is_set(Pages) then
        if utilities.is_set(Periodical) and
            not utilities.in_array(config.CitationClass, {"encyclopaedia","web","book","news"}) then
            Pages = colon .. Pages;
        elseif tonumber(Pages) ~= nil then
            Pages = sepc .." " .. PPrefix .. Pages;
        else
            Pages = sepc .." " .. PPPrefix .. Pages;
        end
    end
    if utilities.is_set(Page) then
        if utilities.is_set(Periodical) and
            not utilities.in_array(config.CitationClass, {"encyclopaedia","web","book","news"}) then
            Page = colon .. Page;
        else
            Page = sepc .." " .. PPrefix .. Page;
        end
    end
    
    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	
    
    TitleNote = utilities.is_set(TitleNote) and (sepc .. " " .. TitleNote) or "";
    
    if utilities.is_set(Language) then
    	if is_dstu then
    		Language = cfg.presentation['sep_colon_dstu2006'] .. (("[" .. SubstLangTemplateIfPossible(Language, is_dstu) .. "]") or wrap( 'dstulanguage', Language ));
    	else	
    		Language = " " .. (SubstLangTemplateIfPossible(Language) or wrap( 'language', Language ));
    	end	
    else
    	Language = "";
    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
    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(Via) then Via = " " .. wrap( 'via', Via ); end
    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(SubscriptionRequired) then
        SubscriptionRequired = sepc .. " " .. cfg.messages['subscription'];
    end
    
    if utilities.is_set(ID) then ID = sepc .." ".. ID; end
    
    ID_list = build_id_list( ID_list, {DoiBroken = DoiBroken, ASINTLD = ASINTLD, IgnoreISBN = IgnoreISBN} );

    if utilities.is_set(URL) then
        URL = " " .. external_link( URL, nil, URLorigin );
    end

    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('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 = " " .. wrap (trans_quoted_title, TransQuote );
			end	
			Quote = Quote .. TransQuote;
        end
	
        Quote = sepc .." " .. wrap( '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 ('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;
        --if not utilities.is_set(ArchiveDate) then
        --    ArchiveDate = utilities.set_message('archive_missing_date');
        --end
        ArchiveDate = ParseDateIfPossible(ArchiveDate)
        if "yes" ~= DeadURL or UrlStatus == "live" 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-not-dead'],
                    { external_link( ArchiveURL, arch_text ), ArchiveDate } );
            else
				Archived = "";
			end    
            if not utilities.is_set(OriginalURL) then
                utilities.set_message('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'] ), ArchiveDate } );
                else
					Archived = "";												-- unset for concatenation
				end
            end
        else																	-- OriginalUrl not set
            utilities.set_message ('archive_missing_url');
			Archived = "";														-- empty string for concatenation
        end
    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; ''" .. 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
    
    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 (непідтримується)]];
	elseif utilities.is_set (TranscriptURL) then
		Transcript = external_link( TranscriptURL, nil, TranscriptURL_origin, nil );
	end
    
    local Publisher;
    if utilities.is_set(Periodical) and
        not utilities.in_array(config.CitationClass, {"encyclopaedia","web","pressrelease"}) then
        if utilities.is_set(PublisherName) then
            if utilities.is_set(PublicationPlace) then
                Publisher = PublicationPlace .. colon .. PublisherName;
            else
                Publisher = PublisherName;  
            end
        elseif utilities.is_set(PublicationPlace) then
            Publisher= PublicationPlace;
        else 
            Publisher = "";
        end
        if utilities.is_set(PublicationDate) then
            if utilities.is_set(Publisher) then
                Publisher = Publisher .. ", " .. wrap( 'published', PublicationDate );
            else
                Publisher = PublicationDate;
            end
        end
        if utilities.is_set(Publisher) then
            Publisher = " (" .. Publisher .. ")";
        end
    else
        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
    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; 
    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, SubscriptionRequired, Lay, Quote }, sepc );
	else
		idcommon = safe_join( { ID_list, URL, Archived, AccessDate, Via, SubscriptionRequired, Lay, Quote }, sepc );
    end

    local text;
    local pgtext = Position .. 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                                             -- закоментував, поки не знаю чи потрібен цей код
                    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.
        text = text:sub(1, -sepc:len() - 1); --Remove final seperator
    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);
    
    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("<span[^>/]*>.-</span>", ""):gsub("%b<>","")) <= 2 then
        z.error_categories = {};
        utilities.set_message('empty_citation');
        z.message_tail = {};
    end
    
    if utilities.is_set(options.id) then 
        text = utilities.substitute (cfg.presentation['cite-id'], {mw.uri.anchorEncode(options.id), mw.text.nowiki(options.class), text});
    else
        text = 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.
    local OCinS = '<span title="' .. OCinSoutput .. '" class="Z3988">' .. empty_span .. '</span>';
    text = text .. OCinS;
    
    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.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
    	
        text = text .. " ";
       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
		text = text .. 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
		text = text .. utilities.substitute (cfg.presentation['hidden-maint'], table.concat (maint_msgs_t, ' '));	-- wrap the group of maint messages with proper presentation and save
    end
    
    no_tracking_cats = no_tracking_cats:ulower();
    if utilities.in_array(no_tracking_cats, {"", "no", "false", "n"}) then
        for _, v in ipairs( z.error_categories ) do
            text = text .. '[[Category:' .. v ..']]';
        end
        for _, v in ipairs (z.maintaince_categories) do									-- append maintenance categories
			text = text .. '[[Category:' .. v ..']]';
        end
		for _, v in ipairs (z.properties_cats) do									-- append properties categories
			text = text .. utilities.substitute (cfg.messages['cat wikilink'], v);
		end
    end
    
    return text
end

-- This is used by templates such as {{cite book}} to create the actual citation text.
function z.citation(frame)
    local pframe = frame:getParent()
    local styles;
    
    local args = {};
    local suggestions = {};
    local error_text;

    local config = {};
    for k, v in pairs( frame.args ) do
        config[k] = v;
        args[k] = v;       
    end    
    
    styles = 'Module:Citation/CS1/styles.css';
    utilities.set_selected_modules (cfg);
    metadata.set_selected_modules (cfg, utilities);
    z = utilities.z;

    for k, v in pairs( pframe.args ) do
        if v ~= '' then
            if not validate( k ) then            
                error_text = "";
                if type( k ) ~= 'string' then
                    -- Exclude empty numbered parameters
                    if v:match("%S+") ~= nil then
                        error_text = utilities.set_message( 'text_ignored', {v});
                    end
                elseif validate( k:ulower() ) then 
                    error_text = utilities.set_message( 'parameter_ignored_suggest', {k, k:ulower()});
                else
                    if #suggestions == 0 then
                        suggestions = mw.loadData( 'Module:Citation/CS1/Suggestions' );
                    end
                    if suggestions[ k:ulower() ] ~= nil then
                        error_text = utilities.set_message( 'parameter_ignored_suggest', {k, suggestions[ k:ulower() ]});
                    else
                        error_text = utilities.set_message( 'parameter_ignored', {k});
                    end
                    if not utilities.is_set (error_text) then
                    	if suggestions[ k:ulower() ] ~= nil then
                    		utilities.set_message( 'parameter_ignored_suggest', {k, suggestions[ k:ulower() ]});
                    	else
                        	utilities.set_message( 'parameter_ignored', {k});
                    	end
                    end	
                end                  
            end
            args[k] = v;
        elseif args[k] ~= nil or (k == 'postscript') then
            args[k] = v;
        end        
    end    
    
    return table.concat ({
    	frame:extensionTag ('templatestyles', '', {src=styles}),
		frame:preprocess( citation0( config, args) )
    	});
end

return z