编辑“︁Module:Citation/CS1”︁

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

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

local dates, year_date_check;													-- functions in Module:Citation/CS1/Date_validation
local add_maint_cat, append_error, make_error_tail, reset_error, set_error, select_one, throw_error;       
																				-- error-related functions in Module:Citation/CS1/Error
local first_set, hyphen_to_dash, is_set, in_array, substitute;					-- simple functions in Module:Citation/CS1/Utilities
local has_invisible_chars, kern_quotes, pend_separator, safe_join, wrap_style, wrap_msg;			
																				-- style-related functions in Module:Citation/CS1/Utilities
local check_for_external_link, make_external_link, make_internal_link;			-- link-related functions in Module:Citation/CS1/Links
local extract_ids, build_id_list, is_embargoed, extract_id_access_levels;		-- functions in Module:Citation/CS1/Identifiers
local get_people, format_people;												-- functions in Module:Citation/CS1/People
local COinS;																	-- functions in Module:Citation/CS1/COinS
local script_concatenate, language_parameter;									-- functions in Module:Citation/CS1/Language

local function load_modules (module_path, module_suffix)
	cfg = mw.loadData (module_path .. 'Configuration' .. module_suffix);		
	whitelist = mw.loadData (module_path .. 'Whitelist' .. module_suffix);
	local validation = require (module_path .. 'Date_validation' .. module_suffix);	
	local identifiers = require (module_path .. 'Identifiers' .. module_suffix);
	local utilities = require (module_path .. 'Utilities' .. module_suffix);
	local people = require (module_path .. 'People' .. module_suffix);
	local links = require (module_path .. 'Links' .. module_suffix);
	local errors = require (module_path .. 'Error' .. module_suffix);
	local coins = require (module_path .. 'COinS' .. module_suffix);
	local languages = require (module_path .. 'Language' .. module_suffix);

	utilities.set_selected_modules (cfg);
	links.set_selected_modules (utilities, errors);
	errors.set_selected_modules (cfg, utilities, links);
	identifiers.set_selected_modules (cfg, utilities, errors, links, validation);
	people.set_selected_modules (cfg, utilities, errors, links);
	coins.set_selected_modules (cfg, utilities, links);
	languages.set_selected_modules (utilities, errors);

	dates = validation.dates;													-- imported functions
	year_date_check = validation.year_date_check;
	
	first_set = utilities.first_set;
	hyphen_to_dash = utilities.hyphen_to_dash;
	is_set = utilities.is_set;
	in_array = utilities.in_array;
	substitute = utilities.substitute;
	
	has_invisible_chars = utilities.has_invisible_chars;
	kern_quotes = utilities.kern_quotes;
	pend_separator = utilities.pend_separator;
	safe_join = utilities.safe_join;
	wrap_style = utilities.wrap_style;
	wrap_msg = utilities.wrap_msg;
	
	make_external_link = links.make_external_link;
	make_internal_link = links.make_internal_link;
	check_for_external_link = links.check_for_external_link;
	
	add_maint_cat = errors.add_maint_cat;
	append_error = errors.append_error;
	make_error_tail = errors.make_error_tail;
	reset_error = errors.reset_error;
	set_error = errors.set_error;
	select_one = errors.select_one;
	throw_error = errors.throw_error;
	
	extract_ids = identifiers.extract_ids;
	build_id_list = identifiers.build_id_list;
	is_embargoed = identifiers.is_embargoed;
	extract_id_access_levels = identifiers.extract_id_access_levels;
	
	get_people = people.get_people;
	format_people = people.format_people;
	
	COinS = coins.COinS;
	
	script_concatenate = languages.script_concatenate;
	language_parameter = languages.language_parameter;

end

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

Categorize and emit an error message when the citation contains one or more deprecated parameters.  The function includes the
offending parameter name to the error message.  

]]

local function deprecated_parameter (name)
	append_error ('deprecated_params', {name});						
end

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

]]

local function discard_parameter (name, label, new_value)
	if is_set (name) then
		append_error ('parameter_discarded', label);
	end
	return new_value;
end

--[[--------------------------< S A N I T I Z E 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 (e.g. yes, y, true, no, etc). If the parameter value is empty or is in the list of allowed values, 
the function returns the value; else, it emits an error message and returns the default value.

]]

local function sanitized_parameter_value (value, name, key, default)
	if not is_set (value) then
		return value;															-- an empty parameter is ok
	elseif in_array (value:lower(), cfg.keywords[key]) then
		return value;
	else
		append_error ('invalid_param_val', {name, value});						-- not an allowed value so add error message
		return default;
	end
end

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

]]

local function extra_text_in_parameter_check (value, type)
	
	local good_patterns = cfg.extra_text_pattern[type]['good'];
	local bad_patterns = cfg.extra_text_pattern[type]['bad'];
	
	for _, pattern in pairs (good_patterns) do
		if value:match (pattern) then
			return;
		end
	end
	
	for _, pattern in pairs (bad_patterns) do
		if value:match (pattern) then
			add_maint_cat ('extra_text', type);
			return;
		end
	end
end

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

Go test all of the date-holding parameters for valid MOS:DATE format and make sure that dates are real dates. This must be done before we do COinS because here is where
we get the date used in the metadata.

Date validation supporting code is in Module:Citation/CS1/Date_validation
]]

local function validate_date (AccessDate, ArchiveDate, Date, DoiBroken, Embargo, LayDate, PublicationDate, Year, COinS_date, origin)
	local error_message = '';
																				-- AirDate has been promoted to Date so not necessary to check it
		anchor_year, error_message = dates ({['access-date']=AccessDate, ['archive-date']=ArchiveDate, ['date']=Date, ['doi-broken-date']=DoiBroken,
			['embargo']=Embargo, ['lay-date']=LayDate, ['publication-date']=PublicationDate, ['year']=Year}, COinS_date);

	if is_set (Year) then
		if is_set (Date) then													-- both |date= and |year= not normally needed; 
			local mismatch = year_date_check (Year, Date)
			if 0 == mismatch then												-- |year= does not match a year-value in |date=
				append_error ('date_year_mismatch', {origin});
			elseif 1 == mismatch then											-- |year= matches year-value in |date=
				add_maint_cat ('date_year');
			end
		end
		anchor_year = Year;														-- Year first for legacy citations and for YMD dates that require disambiguation
	end

	if is_set (error_message) then
		append_error ('bad_date', {error_message});								-- add this error message
	end
	return anchor_year;
end

--[[--------------------------< D I S C A R D _ C H A P T E R >-------------------------------------------------------
仅为保持兼容性而设置。理论上可以直接调用discard_parameter()丢弃相关参数。
]]
	
local function discard_chapter (args)
	local chap_param;
	if is_set (args['Chapter']) then											-- get a parameter name from one of these chapter related meta-parameters
		chap_param = args:ORIGIN ('Chapter');
	elseif is_set (args['TransChapter']) then
		chap_param = args:ORIGIN ('TransChapter');
	elseif is_set (args['ChapterURL']) then
		chap_param = args:ORIGIN ('ChapterURL');
	elseif is_set (args['ScriptChapter']) then
		chap_param = args:ORIGIN ('ScriptChapter')
	elseif is_set (args['ChapterFormat']) then
		chap_param = args:ORIGIN ('ChapterFormat')
	elseif is_set (args['ChapterUrlAccess']) then
		chap_param = args:ORIGIN ('ChapterUrlAccess')	
	end
	if is_set (chap_param) then													-- if we found one
		append_error ('chapter_ignored', {chap_param});							-- add error message
	end
end

--[[--------------------------< C R E A T E _ U R L _ O B J E C T >------------------------------------------

]]

local function create_url_object (url, source, fmt, fmt_source, access, access_source)
	return {
		['url'] = is_set (url) and url or '',
		['origin'] = is_set (source) and source or '',
		['access'] = is_set (access) and sanitized_parameter_value (access, access_source, 'url-access', '') or '',
		['access-origin'] = is_set (access_source) and access_source or '',
		['format'] = is_set (fmt) and fmt or '',
		['format-origin'] = is_set (fmt_source) and fmt_source or '',
		['access-text'] = ''
	}
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 is_set (title_type) then
		if 'none' == 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 E T _ N O _ T R A C K I N G _ C A T S >-----------------------------------------

check this page to see if it is in one of the namespaces that cs1 is not supposed to add to the error categories

]]

local function set_no_tracking_cats (no_tracking, no_tracking_source, this_page)
	local no_tracking_cats = sanitized_parameter_value (no_tracking, no_tracking_source, 'yes_true_y', nil);
	if not is_set (no_tracking_cats) then										-- ignore if we are already not going to categorize this page
		if in_array (this_page.nsText, cfg.uncategorized_namespaces) then
			return 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
				return true;													-- set no_tracking_cats; bail out if one is found
			end
		end
		return false;
	else
		return true;
	end
end

--[[--------------------------< S E T _ C S 1 _ S T Y L E >----------------------------------------------------

Set style settings for CS1 citation templates. Returns separator and postscript settings

]]

local function set_cs1_style (ps)
	if not is_set (ps) then														-- unless explicitely set to something
		ps = '.';																-- terminate the rendered citation with a period
	end
	return '.', ps;																-- separator is a full stop
end

--[[--------------------------< S E T _ C S 2 _ S T Y L E >----------------------------------------------------

Set style settings for CS2 citation templates. Returns separator, postscript, ref settings

]]

local function set_cs2_style (ps, ref)
	if not is_set (ps) then														-- if |postscript= has not been set, set cs2 default
		ps = '';																-- make sure it isn't nil
	end
	if not is_set (ref) then													-- if |ref= is not set
		ref = 'harv';															-- set default |ref=harv
	end
	return ',', ps, ref;														-- separator is a comma
end

--[[--------------------------< G E T _ S E T T I N G S _ F R O M _ C I T E _ C L A S S >----------------------

When |mode= is not set or when its value is invalid, use config.CitationClass and parameter values to establish
rendered style.

]]

local function get_settings_from_cite_class (ps, ref, cite_class)
	local sep;
	if (cite_class == 'citation') then											-- for citation templates (CS2)
		sep, ps, ref = set_cs2_style (ps, ref);
	else																		-- not a citation template so CS1
		sep, ps = set_cs1_style (ps);
	end

	return sep, ps, ref															-- return them all
end

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

Establish basic style settings to be used when rendering the citation.  Uses |mode= if set and valid or uses
config.CitationClass from the template's #invoke: to establish style.

]]

local function set_style (mode, mode_source, ps, ref, quote, cite_class)
	local sep;
	mode = sanitized_parameter_value (mode, mode_source, 'mode', ''):lower();
	if 'cs2' == mode then														-- if this template is to be rendered in CS2 (citation) style
		sep, ps, ref = set_cs2_style (ps, ref);
	elseif 'cs1' == mode then													-- if this template is to be rendered in CS1 (cite xxx) style
		sep, ps = set_cs1_style (ps);
	else																		-- anything but cs1 or cs2
		sep, ps, ref = get_settings_from_cite_class (ps, ref, cite_class);		-- get settings based on the template's CitationClass
	end
	if 'none' == ps:lower() or is_set (quote) then								-- if assigned value is 'none' then set it to empty string
		ps = '';																-- also cs1|2 does not supply terminal punctuation when |quote= is set
	end
	
	return sep, ps, ref
end

--[[--------------------------< S W A P _ U R L S >--------------------------------------------------------------

]]

local function swap_urls (url_object, chapter_url_object, archive_url_object, dead_url)
	local original_url_object = create_url_object ();
	local is_dead = in_array (dead_url, cfg.keywords['deadurl-live']);			-- used later when assembling archived text
	
	if is_set (archive_url_object['url']) then
		if is_set (url_object['url']) then
			original_url_object = url_object;											
			if not is_dead then													
				url_object = archive_url_object;
			end
		elseif is_set (chapter_url_object['url']) then 							-- URL not set so if chapter-url is set apply archive url to it
			original_url_object = chapter_url_object;							
			if not is_dead then
				chapter_url_object = archive_url_object;						
			end
		end
	end
	return original_url_object, url_object, chapter_url_object;
end

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

从x-url-access系列参数生成相应的图标；兼容既有registration, subscription参数，优先级x-url-access > subscription > registration。

]]

local function format_url_access_text (url_object, subscription_required, registration_required)
	local access_text = '';
	local redundant = false;
	local access = url_object['access'];
	local reg = false;
	local sub = false;
	if is_set (access) then
		if (access == 'limited') then
			access_text = cfg.presentation['limited'];							-- 有限度免费访问
		elseif (access == 'registration') then
			access_text = cfg.presentation['registration'];						-- 需要免费注册
			reg = true;
		elseif (access == 'subscription') then
			access_text = cfg.presentation['subscription'];						-- 需要付费订阅
			sub = true;
		else
			access_text = '';	
		end
		if is_set (subscription_required) or is_set (registration_required) then
			redundant = true;
		end
	else
		if is_set (subscription_required) then
			access_text = cfg.presentation['subscription'];						-- 需要免费注册
			sub = true;
			if is_set (registration_required) then
				redundant = true;
			end
		elseif is_set (registration_required) then
			access_text = cfg.presentation['registration'];						-- 需要付费订阅
			reg = true
		else
			access_text = '';													
		end
	end
	if is_set (url_object ['url']) then
		url_object['access-text'] = access_text;
		if sub then
			add_maint_cat ('subscription');
		elseif reg then
			add_maint_cat ('registration');
		end
	else
																				-- 预留报错	
	end
	return redundant;
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 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, cite_class, origin, sepc, lower)
	if not is_set (volume) and not is_set (issue) then
		return '';
	end
	
	if 'magazine' == cite_class or (cite_class =='map' and 'magazine' == origin) then
		if is_set (volume) and is_set (issue) then
			return wrap_msg ('vol-no', {sepc, volume, issue}, lower);
		elseif is_set (volume) then
			return wrap_msg ('vol', {sepc, volume}, lower);
		else
			return wrap_msg ('issue', {sepc, issue}, lower);
		end
	end
	
	local vol = '';
		
	if is_set (volume) then
		if (6 < mw.ustring.len (volume)) then
			vol = wrap_msg ('j-vol', {sepc, volume}, lower);
		else
			vol = wrap_style ('vol-bold', hyphen_to_dash (volume));
		end
	end
	if is_set (issue) then
		return vol .. wrap_msg ('j-issue', issue, lower);
	end
	return vol;
end

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

Build insource_location meta-parameter from |page(s)= , |sheet(s)= , |at= and other relevant parameters.

]]

local function format_insource_location (page, pages, sheet, sheets, at, minutes, time, time_caption, section, sections, inset, cite_class, origin, sepc, nopp, lower)
	local text = '';
	
	if is_set (sheet) then
		if 'journal' == origin then
			text = wrap_msg ('j-sheet', sheet, lower);
		else
			text = wrap_msg ('sheet', {sepc, sheet}, lower);
		end
	elseif is_set (sheets) then
		if 'journal' == origin then
			text = wrap_msg ('j-sheets', sheets, lower);
		else
			text = wrap_msg ('sheets', {sepc, sheets}, lower);
		end
	end

	local is_journal = 'journal' == cite_class or (cite_class == 'map' and 'journal' == origin);
	if is_set (page) then
		if is_journal then
			text = wrap_msg ('j-page(s)', page, lower);
		elseif not is_set (nopp) then
			text = wrap_msg ('p-prefix', {sepc, page}, lower);
		else
			text = wrap_msg ('nopp', {sepc, page}, lower);
		end
	elseif is_set (pages) then
		if is_journal then
			text = wrap_msg ('j-page(s)', pages, lower);
		elseif tonumber (pages) ~= nil and not is_set (nopp) then				-- if pages is only digits, assume a single page number
			text = wrap_msg ('p-prefix', {sepc, pages}, lower);
		elseif not is_set (nopp) then
			text = wrap_msg ('pp-prefix', {sepc, pages}, lower);
		else
			text = wrap_msg ('nopp', {sepc, pages}, lower);
		end
	end
	
	if is_set (minutes) then
		text = pend_separator (wrap_msg ('minutes', minutes, lower), sepc, true) .. text;
	else
		if is_set (time) then
			if not is_set (time_caption) then
				text = pend_separator (wrap_msg ('event', time, lower), sepc, true) .. text;
			else
				text = pend_separator (time_caption .. ' ' .. time .. text, sepc, true);
			end
		end
	end
	
	text = text .. pend_separator (at, sepc, true);
	text = text .. pend_separator (wrap_msg ('inset', inset, lower), sepc, true);
	
	if is_set (sections) then
		text = text .. pend_separator (wrap_msg ('sections', sections, lower), sepc, true);
	elseif is_set (section) then
		text = text .. pend_separator (wrap_msg ('section', section, lower), sepc, true);
	end
	
	return text;		
end

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

]]

local function format_publisher (publisher_name, publication_place, periodical, cite_class, sepc)
	local publisher = '';
	
	if is_set (publisher_name) then
		if is_set (publication_place) then
			publisher = publication_place .. ': ' .. publisher_name;
		else
			publisher = publisher_name;  
		end
	elseif is_set (publication_place) then
		publisher = publication_place;
	end
	
	if is_set (publisher) then
		if is_set (periodical) and
			not in_array (cite_class, {'encyclopaedia', 'web', 'pressrelease', 'podcast'}) then
			publisher = ' (' .. publisher .. ')';
		else
			publisher = pend_separator (publisher, sepc, true);	
		end
	end
	return publisher;
end

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

Format an external link that may or may not be raw.

]]

local function format_external_link (text, url_object, sepc)
	if is_set (text) then
		if is_set (url_object['url']) then
			text = make_external_link (url_object['url'], text, url_object['origin']);
		end
		text = pend_separator (text .. url_object['format'], sepc, true);
	elseif is_set (url_object['url']) then
		text = make_external_link (url_object['url'], nil, url_object['origin']);
	end
	return text;
end

--[[-------------------------< F O R M A T _ C O N F E R E N C E >----------------------------------------

]]

local function format_conference (conference, conference_url_object, periodical, cite_class, sepc)
	local  conf_text = format_external_link (conference, conference_url_object, sepc);
	if 'speech' == cite_class and is_set (periodical) then
																				-- if cite speech, periodical (perhaps because of an included |website= or |journal= parameter) is set; 
		conf_text = pend_separator (conf_text, sepc, false);					-- then add appropriate punctuation to the end of the conference variable if set.
	end
	return conf_text;
end

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

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

]]

local function format_chapter_title (scriptchapter, chapter, transchapter, chapter_url_object, no_quotes, cite_class, title_type, sepc)
	local chapter_error = '';
	
	if not is_set (chapter) then
		chapter = '';															-- to be safe for concatenation
	else
		if false == no_quotes then
			chapter = kern_quotes (chapter);									-- if necessary, separate chapter title's leading and trailing quote marks from Module provided quote marks
			chapter = wrap_style ('quoted-title', chapter);
		end
	end

	chapter = script_concatenate (chapter, scriptchapter)						-- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped

	if is_set (transchapter) then
		transchapter = wrap_style ('trans-quoted-title', transchapter);
		if is_set (chapter) then
			chapter = chapter ..  ' ' .. transchapter;
		else																	-- here when transchapter without chapter or script-chapter
			chapter = transchapter;
			chapter_error = ' ' .. set_error ('trans_missing_title', {'chapter'});
		end
	end
	if is_set (chapter_url_object['url']) then
		chapter = make_external_link (chapter_url_object['url'], chapter, chapter_url_object['origin']) .. chapter_url_object['access-text'];		
																				-- adds bare_url_missing_title error if appropriate
	end
	chapter = chapter .. chapter_error;
	
	if is_set (chapter) then
		if 'map' == cite_class and is_set (title_type) then
			chapter = chapter .. ' ' .. title_type;
		end
		chapter = pend_separator (chapter .. chapter_url_object['format'], sepc,  false);
	else																		-- |chapter= not set but |chapter-format= is so ...
		chapter = pend_separator (chapter_url_object['format'], sepc, false);	-- ... ChapterFormat has error message, we want to see it
	end
	
	return chapter;
end

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

Format the five title parameters: |script-title=, |title=, |trans-title=, |title-link=, and |url= into a single Title meta-
parameter (url_origin and title_link_origin used for error messages).

]]

local function format_main_title (title, title_link, title_link_origin, script_title, trans_title, url_object, no_chapter_format, cite_class, periodical)
	if is_set (title_link) and is_set (title) then
		title = make_internal_link (title_link, title, title_link_origin);
	end
	if no_chapter_format or
		('map' == cite_class and is_set (periodical)) then						-- special case for cite map when the map is in a periodical treat as an article			
		title = kern_quotes (title);											-- if necessary, separate title's leading and trailing quote marks from Module provided quote marks
		title = wrap_style ('quoted-title', title);
	
		title = script_concatenate (title, script_title);						-- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
		trans_title= wrap_style ('trans-quoted-title', trans_title );
	elseif 'report' == cite_class then											-- no styling for cite report
		title = script_concatenate (title, script_title);						-- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
		trans_title= wrap_style ('trans-quoted-title', trans_title );			-- for cite report, use this form for trans-title
	else
		title = wrap_style ('italic-title', title);
		title = script_concatenate (title, script_title);						-- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
		trans_title = wrap_style ('trans-italic-title', trans_title);
	end

	local trans_error = '';
	if is_set (trans_title) then
		if is_set (title) then
			trans_title = ' ' .. trans_title;
		else
			trans_error = ' ' .. set_error ('trans_missing_title', {'title'});
		end
	end
	
	title = title .. trans_title;
	
	if is_set (title) then
		if not is_set (title_link) and is_set (url_object['url']) then 
			title = make_external_link (url_object['url'], title, url_object['origin']) .. url_object['access-text'] .. trans_error .. url_object['format'];
			url_object = create_url_object ();
		else
			title = title .. trans_error;
		end
	end
	return title, url_object;
end

--[[--------------------------< F O R M A T  _ F O R M A T >--------------------------------------------------------

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

]]

local function format_format (args)
	for _, url_object in pairs (args) do
		if is_set (url_object['format']) then
			url_object['format'] = wrap_style ('format', url_object['format']);	-- add leading space, parenthases, resize
			if not is_set (url_object['url']) then
				url_object['format'] = url_object['format'] .. set_error ('format_missing_url', {url_object['format-origin'], url_object['origin']});	
																				-- add an error message
			end
		elseif is_set (url_object['url']) then
			if url_object['url']:match ('%.pdf[%?#]?') or url_object['url']:match ('%.PDF[%?#]?') then
																				-- format is not set so if url is a pdf file then
				url_object['format'] = wrap_style ('format', 'PDF');			-- set format to pdf
			end
		end
	end
end

--[[--------------------------< F O R M A T _ A C C E S S D A T E >----------------------------------------------

]]

local function format_accessdate (accessdate, sepc, lower)
	if is_set (accessdate) then																				-- first, wrap in nowrap span if date in appropriate format
		if accessdate:match ('^%d%d%d%d%-%d%d%-%d%d$') then
			accessdate = wrap_style ('nowrap1', accessdate);					-- when accessdate is YYYY-MM-DD format wrap in nowrap span: <span ...>YYYY-MM-DD</span>.
		elseif accessdate:match('^%a+%s*%d%d?,%s+%d%d%d%d$') or accessdate:match ('^%d%d?%s*%a+%s+%d%d%d%d$') then
			local cap, cap2 = string.match (accessdate, '^(.*)%s+(%d%d%d%d)$');
			accessdate = wrap_style ('nowrap2', {cap, cap2});					-- when accessdate is DD MMMM YYYY or is MMMM DD, YYYY then wrap in nowrap span: <span ...>DD MMMM</span> YYYY or <span ...>MMMM DD,</span> YYYY
		end
		accessdate =  ' ' .. wrap_msg ('retrieved', accessdate, lower);			-- add retrieved text
		accessdate = wrap_style ('accessdate', {sepc, accessdate});				-- allow editors to hide accessdates
	end
	return accessdate;
end

--[[--------------------------< F O R M A T _ I D >----------------------------------------------------
]]

local function format_id (id, docket, sepc, lower)
	id = pend_separator (id, sepc, true);
	return pend_separator (wrap_msg ('docket', docket, lower), sepc, true) .. id;
end

--[[--------------------------< F O R M A T _ Q U O T E >----------------------------------------------
]]

local function format_quote (quote, sepc)
	if is_set (quote) then
		if quote:sub (1, 1) == '"' and quote:sub (-1, -1) == '"' then			-- if first and last characters of quote are quote marks
			quote = quote:sub (2, -2);											-- strip them off
		end
		return pend_separator (wrap_style ('quoted-text', quote), sepc, true);	-- wrap in <q>...</q> tags
	end
	return '';
end

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

]]

local function format_archive (archive_url_object, original_url_object, archive_date, dead_url, sepc, lower)
	local archived = '';
	if is_set (archive_url_object['url']) then
		if not is_set (archive_date) then
			archive_date = set_error ('archive_missing_date');
		end
		if in_array (dead_url, cfg.keywords['deadurl-live']) then
			local arch_text = cfg.messages['archived'];
			if (lower) then arch_text = arch_text:lower(); end;
			archived = pend_separator (wrap_msg ('archived-not-dead', {make_external_link (archive_url_object['url'], arch_text, archive_url_object['origin']) .. archive_url_object['format'], archive_date }, lower), sepc, true);
			if not is_set (original_url_object['url']) then
				archived = archived .. ' ' .. set_error ('archive_missing_url');							   
			end
		elseif is_set (original_url_object['url']) then							-- dead_url is not live, so it should be empty, dead or unfit
			if in_array (dead_url, cfg.keywords['deadurl-unfit']) then
				archived = pend_separator (wrap_msg('archived-unfit', archive_date, lower), sepc, true);		
																				-- format already styled
			else																-- dead_url is empty or dead
				archived = pend_separator (wrap_msg ('archived-dead',
					{make_external_link (original_url_object['url'], cfg.messages['original'], original_url_object['origin']) .. original_url_object['access-text'] .. original_url_object['format'], archive_date }, lower), sepc, true);
																				-- format already styled
			end
		else
			archived = pend_separator (wrap_msg ('archived-missing', 
				{set_error ('archive_missing_url'), archive_date }, lower), sepc, true);
		end
	elseif is_set (original_url_object['format']) then
		archived = original_url_object['format'];								-- if set and archive_url not set archive_format has error message
	end
	return archived;
end

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

]]

local function format_lay (lay_url_object, lay_date, lay_source, sepc, lower)
	local lay = '';
	if is_set (lay_url_object['url']) then
		if is_set (lay_date) then lay_date = ' (' .. lay_date .. ')' end
		if is_set (lay_source) then 
			lay_source = wrap_msg ('lay source', lay_source, lower);
		else
			lay_source = '';
		end
		local lay_sum = cfg.messages['lay summary'];
		if lower then
			lay_sum = lay_sum:lower();
		end
		lay = pend_separator (make_external_link (lay_url_object['url'], lay_sum, lay_url_object['origin']) .. lay_url_object['format'] .. lay_source .. lay_date, sepc, true);
	else 																		-- Test if |lay-format= is given without giving a |lay-url=
		lay = pend_separator (lay_url_object['format'], sepc, true);			-- if set and LayURL not set, then LayFormat has error message
	end
	return lay;
end

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

local function format_periodical (periodical, title, title_note, sepc)
	if is_set (periodical) then
		if is_set (title) or is_set (title_note) then 
			return pend_separator (wrap_style ('italic-title', periodical), sepc, true);
		else 
			return wrap_style ('italic-title', periodical);
		end
	end
	return '';
end

--[[--------------------------< A N C H O R _ I D >------------------------------------------------------------

Generates a CITEREF anchor ID if we have at least one name or a date.  Otherwise returns an empty string.

namelist is one of the contributor-, author-, or editor-name lists chosen in that order.  year is Year or anchor_year.

]]

local function anchor_id (namelist, year)
	local names={};																-- a table for the one to four names and year
	for i,v in ipairs (namelist) do												-- loop through the list and take up to the first four last names
		names[i] = v.last 
		if i == 4 then break end												-- if four then done
	end
	table.insert (names, year);													-- add the year at the end
	local id = table.concat (names);											-- concatenate names and year for CITEREF id
	if is_set (id) then															-- if concatenation is not an empty string
		return 'CITEREF' .. id;													-- add the CITEREF portion
	else
		return '';																-- return an empty string; no reason to include CITEREF id in this citation
	end
end

--[[--------------------------< F O R M A T _ C I T A T I O N >--------------------------------------------

]]

local function format_citation (body, cite_class, ref, namelist, year, ocins_output, no_tracking_cats)
	local options = {};
	
	if is_set (cite_class) and cite_class ~= 'citation' then
		options.class = 'citation ' .. cite_class;								-- class=citation required for blue highlight when used with |ref=
	else
		options.class = 'citation';
	end
	
	if is_set (ref) and ref:lower() ~= 'none' then								-- set reference anchor if appropriate
		local id = ref
		if ('harv' == ref ) then
			id = anchor_id (namelist, year);									-- go make the CITEREF anchor
		end
		options.id = id;
	end
	
	if string.len (body:gsub ('<span[^>/]*>.-</span>', ''):gsub ('%b<>','')) <= 2 then
		reset_error ({'err_cats'});
		body = set_error ('empty_citation');
		reset_error ({'msg_tail'});
	end
	
	local text;
	
	if is_set (options.id) then
		text = wrap_style ('citation-with-id', {mw.uri.anchorEncode (options.id), mw.text.nowiki (options.class), body});
	else
		text = wrap_style ('citation-no-id', {mw.text.nowiki (options.class), body});
	end	
	
	text = text .. wrap_style ('OCinS', ocins_output);
	text = text .. make_error_tail (no_tracking_cats);							-- append error/maintenance messages/categories to the citation
	
	return text;
end

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

如果citation_class为citation（{{citation}}），根据periodical系列参数的设置情况推断实际的引用类型。

]]

local function deduce_citation_class (A, naive_class)
	local deduced_class;
	local periodical = A['Periodical'];
	local origin = A:ORIGIN ('Periodical');
	
	for cite_class, aliases in pairs (cfg.periodical.parameters) do
		if cite_class ~= '_general' then
			for _, aliase in pairs (aliases) do
				if origin == aliase then
					deduced_class = cite_class;
				end
			end
		end
	end
	
	if (naive_class == 'citation') then
		if is_set (deduced_class) then
			return deduced_class, true;
		end
	elseif (naive_class ~= deduced_class) then
		local check_list = cfg.periodical.compatibility[naive_class];
		if is_set (check_list) then
			if is_set (check_list['drop']) and in_array (deduced_class, check_list['drop']) then
				A['Periodical'] = discard_parameter (periodical, origin, nil);
			elseif is_set (check_list['warn']) and in_array (deduced_class, check_list['warn']) then
				append_error ('periodical', {origin, naive_class, deduced_class, check_list['suggest']});
			end
		end
	end
	return naive_class, false;
end


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

Argument wrapper.  This function provides support for argument mapping defined in the configuration file so that
multiple names can be transparently aliased to single internal variable.

]]

local function argument_wrapper (args)
	local origin = {};
	
	return setmetatable ({
		ORIGIN = function (self, k)
			local dummy = self[k]; --force the variable to be loaded.
			return origin[k];
		end
	},
	{
		__index = function (tbl, k)
			if origin[k] ~= nil then
				return nil;
			end
			
			local args, list, v = args, cfg.aliases[k];
			
			if type (list) == 'table' then
				v, origin[k] = select_one (args, list, 'redundant_parameters');
				if origin[k] == nil then
					origin[k] = ''; -- Empty string, not nil
				end
			elseif list ~= nil then
				v, origin[k] = args[list], list;
			else
				-- maybe let through instead of raising an error?
				-- v, origin[k] = args[k], k;
				throw_error ('unknown_argument_map');
			end
			
			-- Empty strings, not nil;
			if v == nil then
				v = cfg.defaults[k] or '';
				origin[k] = '';
			end
			
			tbl = rawset (tbl, k, v);
			return v;
		end,
	});
end

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

This is the main function doing the majority of the citation formatting.

]]

local function do_citation (config, args)
	
	--local variables that are not cs1 parameters
	local this_page = mw.title.getCurrentTitle();								-- also used for COinS and for language

	--[[ 
	Load Input Parameters
	The argument_wrapper facilitates the mapping of multiple aliases to single internal variable.
	]]
	local A = argument_wrapper (args);
	local citation_class, did_duduction = deduce_citation_class (A, config.CitationClass);

	-- Pick out the relevant fields from the arguments.  Different citation templates
	-- define different field names for the same underlying things.	
	------------------------------------------------- Get dates
	local Year = A['Year'];
	local PublicationDate = A['PublicationDate'];
	local OrigYear = A['OrigYear'];
	local Date = A['Date'];
	local Dateorigin = A:ORIGIN ('Date');
	local LayDate = A['LayDate'];
	------------------------------------------------- Get title data
	local Title = A['Title'];
	local ScriptTitle = A['ScriptTitle'];
	local Conference = A['Conference'];
	local TransTitle = A['TransTitle'];
	local TitleNote = A['TitleNote'];
	local TitleLink = A['TitleLink'];
	local TitleLinkorigin = A:ORIGIN ('TitleLink');
	
	local Periodical = A['Periodical'];
	local Periodical_origin = A:ORIGIN ('Periodical');							-- get the name of the periodical parameter

	local Series = A['Series'];
	
	local ConferenceURLobject = create_url_object (A['ConferenceURL'], A:ORIGIN ('ConferenceURL'), A['ConferenceFormat'], A:ORIGIN ('ConferenceFormat'));
	local ArchiveURLobject = create_url_object (A['ArchiveURL'], A:ORIGIN ('ArchiveURL'), A['ArchiveFormat'], A:ORIGIN ('ArchiveFormat'));
	local URLobject = create_url_object (A['URL'], A:ORIGIN ('URL'), A['Format'], A:ORIGIN ('Format'),A['UrlAccess'], A:ORIGIN ('UrlAccess'));
	local TranscriptURLobject = create_url_object (A['TranscriptURL'], A:ORIGIN ('TranscriptURL'), A['TranscriptFormat'], A:ORIGIN ('TranscriptFormat'));
	local LayURLobject = create_url_object (A['LayURL'], A:ORIGIN ('LayURL'), A['LayFormat'], A:ORIGIN ('LayFormat'));
	
	local Volume = A['Volume'];
	local Issue = A['Issue'];
	local Page = A['Page'];
	local Pages = hyphen_to_dash (A['Pages']);
	local At = A['At'];

	if not in_array (citation_class, cfg.args_support['templates_using_volume']) then
		Volume = discard_parameter (Volume, A:ORIGIN ('Volume'), nil);
	end
	if not in_array (citation_class, cfg.args_support['templates_using_issue']) then
		if (A:ORIGIN ('Issue') ~= 'number') then
			Issue = discard_parameter (Issue, A:ORIGIN ('Issue'), nil);
		else
			Issue = nil;
		end
	end
	if in_array (citation_class, cfg.args_support['templates_not_using_page']) then
		Page = discard_parameter (Page, A:ORIGIN ('Page'), nil);
		Pages = discard_parameter (Pages, A:ORIGIN ('Pages'), nil);	
		At = discard_parameter (At, A:ORIGIN ('At'), nil);
	end
	
	local Minutes = A['Minutes'];
	local Time = A['Time'];
	local TimeCaption = A['TimeCaption'];
	
	if not in_array (citation_class, cfg.args_support['templates_involving_time']) then
		Minutes = discard_parameter (Minutes, A:ORIGIN ('Minutes'), nil);
		Time = discard_parameter (Time, A:ORIGIN ('Time'), nil);
		TimeCaption = discard_parameter (TimeCaption, A:ORIGIN ('TimeCaption'), nil);
	end
	
	local Sheet = A['Sheet'];
	local Sheets = A['Sheets'];
	local Section = A['Section'];
	local Sections = A['Sections'];
	local Inset = A['Inset'];
	
	if not ('map' == citation_class) then
		Sheet = discard_parameter (Sheet, A:ORIGIN ('Sheet'), nil);
		Sheets = discard_parameter (Sheets, A:ORIGIN ('Sheets'), nil);
		Sections = discard_parameter (Sections, A:ORIGIN ('Sections'), nil);
		Inset = discard_parameter (Inset, A:ORIGIN ('Inset'), nil);
	end
	
--[[
不知道哪个“天才”想出来的点子，现行引用模板里，section一个参数多个涵义。
在书籍类引用中，section是章节名称，在地图引用中，section是地图的区域编号。
所以一旦知道citation_class不是地图，就可以丢弃上述几乎全部参数，
唯独section参数需要留到检查章节相关参数时一并进行检查。
]]

	local Chapter = '';
	local ScriptChapter = '';
	local TransChapter = '';
	local ChapterURLobject;
	local no_chapter_format = in_array (citation_class, cfg.args_support['templates_not_using_chapter_format']);
	
	if in_array (citation_class, cfg.args_support['templates_not_using_chapter']) then
		ChapterURLobject = create_url_object ();
		discard_chapter (A);
		if not ('map' == citation_class) then
			Section = discard_parameter (Section, A:ORIGIN ('Section'), nil);
		end
	else
		Chapter = A['Chapter'];
		ScriptChapter = A['ScriptChapter'];
		TransChapter = A['TransChapter'];
		ChapterURLobject = create_url_object (A['ChapterURL'], A:ORIGIN ('ChapterURL'), A['ChapterFormat'], A:ORIGIN ('ChapterFormat'), A['ChapterUrlAccess'], A:ORIGIN ('ChapterUrlAccess'));
		if is_set (Chapter) then
			if is_set (Section) then
				select_one (args, {'chapter', 'contribution', 'section'}, 'redundant_parameters');
			end
		else
			Chapter = Section;
			Section = nil;
		end
	end
	
	local Edition = A['Edition'];
	local PublicationPlace = A['PublicationPlace']
	local Place = A['Place'];
	
	local PublisherName = A['PublisherName'];
	local RegistrationRequired = sanitized_parameter_value (A['RegistrationRequired'], A:ORIGIN ('RegistrationRequired'), 'yes_true_y', nil);
	local SubscriptionRequired = sanitized_parameter_value (A['SubscriptionRequired'], A:ORIGIN ('SubscriptionRequired'), 'yes_true_y', nil);
	
	local Via = A['Via'];
	local AccessDate = A['AccessDate'];
	local ArchiveDate = A['ArchiveDate'];
	local Agency = A['Agency'];
	local DeadURL = sanitized_parameter_value (A['DeadURL'], A:ORIGIN ('DeadURL'), 'deadurl', '');

	local Language = A['Language'];
	local DoiBroken = A['DoiBroken'];
	local ID = A['ID'];
	local ASINTLD = A['ASINTLD'];
	local IgnoreISBN = sanitized_parameter_value (A['IgnoreISBN'], A:ORIGIN ('IgnoreISBN'), 'yes_true_y', nil);
	
	local Embargo = A['Embargo'];
	local Class = A['Class'];													-- arxiv class identifier

	local ID_list = extract_ids (args);
	local ID_access_levels = extract_id_access_levels (args, ID_list);

	local LaySource = A['LaySource'];
	local Transcript = A['Transcript'];

	local no_tracking_cats = set_no_tracking_cats (A['NoTracking'], A:ORIGIN ('NoTracking'), this_page);
	
	local Quote = A['Quote'];
	local sepc, PostScript, Ref = set_style (A['Mode'], A:ORIGIN ('Mode'), A['PostScript'], A['Ref'], Quote, config.CitationClass);
	if is_set (Quote) and is_set (A['PostScript']) then
		select_one (args, {'postscript', 'quote', 'quotation'}, 'redundant_parameters');
	end
	
	local use_lowercase = ( sepc == ',' );										-- used to control capitalization for certain static text

-- check for insource-location-related parameters like |page=, |pages= or |at=. 请注意section参数有歧义，如果section跟书有关系，上面已经被清空了，这里不纳入检查。
	select_one (args, {'at', 'time', 'minutes'}, 'redundant_parameters');
	select_one (args, {'page', 'p', 'pp', 'pages', 'at', 'time', 'minutes', 'sheet', 'sheets'}, 'redundant_parameters');
	if is_set (Section) then
		select_one (args, {'at', 'section', 'sections'}, 'redundant_parameters');
	else
		select_one (args, {'at', 'sections'}, 'redundant_parameters');
	end
																				-- Dummy calls simply to get the error messages and categories
	local NoPP = sanitized_parameter_value (A['NoPP'], A:ORIGIN ('NoPP'), 'yes_true_y', nil);

	if is_set (Page) then
		if is_set (Pages) or is_set (At) then
			Pages = '';															-- unset the others
			At = '';
		end
		extra_text_in_parameter_check (Page, 'page');							-- add this page to maint cat if |page= value begins with what looks like p. or pp.
	elseif is_set (Pages) then
		if is_set (At) then
			At = '';															-- unset
		end
		extra_text_in_parameter_check (Pages, 'page');							-- add this page to maint cat if |pages= value begins with what looks like p. or pp.
	end	

-- both |publication-place= and |place= (|location=) allowed if different
	if not is_set (PublicationPlace) and is_set (Place) then
		PublicationPlace = Place;							-- promote |place= (|location=) to |publication-place
	end
	
	if PublicationPlace == Place then Place = ''; end		-- don't need both if they are the same
	
	if is_set (Edition) then
		extra_text_in_parameter_check (Edition, 'edition');
	end
	
	------------------------------------------------- Get people
	local NameListFormat = sanitized_parameter_value (A['NameListFormat'], A:ORIGIN ('NameListFormat'), 'name-list-format', '');
	local LastAuthorAmp = sanitized_parameter_value (A['LastAuthorAmp'], A:ORIGIN ('LastAuthorAmp'), 'yes_true_y', nil);
	local contributors_valid = in_array (citation_class, cfg.args_support['templates_using_contributor']);	
	
	local Authors, Contributors, Editors, Translators, Contribution, NameList, multiple_editors, has_contributors = 
		get_people (
			{
			vauthors = A['Vauthors'], authors = A['Authors'], veditors = A['Veditors'], editors = A['Editors'], contribution = A['Contribution'], coauthors = A['Coauthors']
		}, {
			displayauthors = A['DisplayAuthors'], displayeditors = A['DisplayEditors'], contributorsvalid = contributors_valid,  namelistformat = NameListFormat, lastauthoramp = LastAuthorAmp
		}, args, this_page.name
		);																		-- (co-)authors, contributors, editors and translators
	
	local TitleType = set_titletype (citation_class, A['TitleType']);			-- handle type parameter for those CS1 citations that have default values
	
-- special case for cite thesis
	local Degree = A['Degree'];
	if 'thesis' == citation_class then
		if (is_set (Degree)) then
			TitleType = wrap_msg ('thesis with type', Degree, use_lowercase);
		else
			TitleType = wrap_msg ('thesis no type', 'placeholder', use_lowercase);
		end
	else
		Degree = discard_parameter (Degree, A:ORIGIN ('Degree'), nil);
	end
	
	local Others = A['Others'];
	
--[[
Parameter remapping for cite encyclopedia:
When the citation has these parameters:
	|encyclopedia and |title then map |title to |article and |encyclopedia to |title
	|encyclopedia and |article then map |encyclopedia to |title
	|encyclopedia then map |encyclopedia to |title

	|trans_title maps to |trans_chapter when |title is re-mapped
	|url maps to |chapterurl when |title is remapped

All other combinations of |encyclopedia, |title, and |article are not modified

]]

	local Encyclopedia;
	local Entry = A['Entry'];

	if (citation_class == 'encyclopaedia') then									-- test code for citation
		local entry_redundant = false
		Encyclopedia = Periodical;
		if is_set (Periodical) then												
			if is_set (Title) or is_set (ScriptTitle) then
				Chapter = Title;
				ScriptChapter = ScriptTitle;
				ScriptTitle = '';
				TransChapter = TransTitle;
				TransTitle = '';
				ChapterURLobject = URLobject;
				URLobject = create_url_object ();
				if not is_set (ChapterURLobject['url']) and is_set (TitleLink) then
					Chapter = make_internal_link (TitleLink, Chapter, TitleLinkorigin);
				end
				TitleLink = '';
				entry_redundant = is_set (Entry);
			elseif is_set (Entry) then
				Chapter = Entry;
				ChapterURLobject = URLobject;
				URLobject = create_url_object ();
			end
			Title = Periodical;													-- |encyclopedia set and |article set or not set so map |encyclopedia to |title
			Periodical = '';													-- redundant so unset
		else
			if is_set (Title) or is_set (ScriptTitle) then
				entry_redundant = is_set (Entry);
			else
				Title = Entry;
			end
		end
		if entry_redundant then
			select_one (args, {'title', 'script-title', 'article', 'entry'}, 'redundant_parameters');
		end
	else 
		Entry = discard_parameter (Entry, A:ORIGIN ('Entry'), nil);
	end
	
-- Special case for cite report.	
	local Docket = A['Docket'];
	if citation_class == 'report' then
		if is_set (Docket) then
			if is_set (ID) then
				select_one (args, {'id', 'docket'}, 'redundant_parameters');
			end
			ID = Docket;														-- for cite report when |docket= is set, overwrite ID even if |id= is set
			Docket = '';
		end
	elseif citation_class ~= 'thesis' then
		discard_parameter (Docket, A:ORIGIN ('Docket'), '');
	end

-- Special case for cite techreport.
	local Num = A['Number'];
	if citation_class == 'techreport' then										-- special case for cite techreport
		if is_set (Num) then													-- cite techreport uses 'number', which other citations alias to 'issue'
			if not is_set (ID) then												-- can we use ID for the "number"?
				ID = Num;														-- yes, use it
			else																-- ID has a value so emit error message
				select_one (args, {'id', 'number'}, 'redundant_parameters');
			end
		end
	elseif not is_set (Issue) then
		Num = discard_parameter (Num, A:ORIGIN ('Number'), nil);
	end

-- special case for cite interview
	local Callsign = A['Callsign'];
	local City = A['City'];
	local Program = A['Program'];

	if (citation_class == 'interview') then
		if is_set (Program) then
			ID = ' ' .. Program;
		end
		if is_set (Callsign) then
			if is_set (ID) then
				ID = ID .. pend_separator (Callsign, sepc, true);
			else
				ID = ' ' .. Callsign;
			end
		end
		if is_set (City) then
			if is_set (ID) then
				ID = ID .. pend_separator (City, sepc, true);
			else
				ID = ' ' .. City;
			end
		end

		if is_set (Others) then
			Others = wrap_msg ('interview', {TitleType, Others}, use_lowercase);
			TitleType = '';
		end
	else
		Callsign = discard_parameter (Callsign, A:ORIGIN ('Callsign'), nil );
		City = discard_parameter (City, A:ORIGIN ('City'), nil );
		Program = discard_parameter (Program, A:ORIGIN ('Program'), nil);
	end
	
	if is_set (TitleType) then													-- if type parameter is specified
		TitleType = wrap_msg ('type', TitleType, use_lowercase);				-- display it in parentheses
	end
-- Account for the oddity that is {{cite conference}} or {{cite speech}}.

	local BookTitle = A['BookTitle'];
	if 'conference' == citation_class then
		if is_set (BookTitle) then
			ChapterURLobject = URLobject;
			URLobject = create_url_object ();
			TransChapter = TransTitle;
			TransTitle = '';
			Chapter = Title;
			Title = BookTitle;
		end
	else
		BookTitle = discard_parameter (BookTitle, A:ORIGIN ('BookTitle'), nil); 
		if 'speech' == citation_class then
			TitleNote = discard_parameter (TitleNote, A:ORIGIN ('TitleNote'), TitleType);
																				-- override whatever may be the value assigned to TitleNote (through |department=) and forces it to be " (Speech)" so that the annotation directly follows the |title= parameter value in the citation rather than the |event= parameter value (if provided).
			TitleType = '';														-- annotate the citation
		else
			Conference = discard_parameter (Conference, A:ORIGIN ('Conference'), '');
																				-- not cite conference or cite speech so make sure this is empty string
		end
	end

-- cite map oddities
	local Cartography = A['Cartography'];
	local Scale = A['Scale'];
	
	if citation_class == 'map' then
		Chapter = A['Map'];
		TransChapter = A['TransMap'];
		ChapterURLobject = create_url_object (A['MapURL'], A:ORIGIN ('MapURL'), A['MapFormat'], A:ORIGIN ('MapFormat'), A['MapUrlAccess'], A:ORIGIN ('MapUrlAccess'));
		Cartography = pend_separator (wrap_msg ('cartography', Cartography, use_lowercase), sepc, true);
		Scale = pend_separator (Scale, sepc, true);
	else
		Cartography = discard_parameter (Cartography, A:ORIGIN ('Cartography'), '');
		Scale = discard_parameter (Scale, A:ORIGIN ('Scale'), '');
		discard_parameter (A['Map'], A:ORIGIN ('Map'), nil);
		discard_parameter (A['MapURL'], A:ORIGIN ('MapURL'), nil);
		discard_parameter (A['TransMap'], A:ORIGIN ('TransMap'), nil);
		discard_parameter (A['MapFormat'], A:ORIGIN ('MapFormat'), nil);
		discard_parameter (A['MapUrlAccess'], A:ORIGIN ('MapUrlAccess'), nil);
	end

-- Account for the oddities that are {{cite episode}} and {{cite serial}}, before generation of COinS data.
	if 'episode' == citation_class or 'serial' == citation_class then
		local AirDate = A['AirDate'];
		local SeriesLink = A['SeriesLink'];
		local Network = A['Network'];
		local Station = A['Station'];
		local s, n = {}, {};
																				-- do common parameters first
		if is_set (Network) then table.insert (n, Network); end
		if is_set (Station) then table.insert (n, Station); end
		ID = table.concat (n, sepc .. ' ');
		
		if is_set (AirDate) then
			if not is_set (Date) then											-- promote airdate to date
				Date = AirDate;
				Dateorigin = A:ORIGIN ('AirDate');
			else
				select_one (args, {'date', 'air-date', 'airdate'}, 'redundant_parameters');
			end
		end

		if 'episode' == citation_class then										-- handle the oddities that are strictly {{cite episode}}
			local Season = A['Season'];
			local SeriesNumber = A['SeriesNumber'];

			if is_set (Season) and is_set (SeriesNumber) then					-- these are mutually exclusive so if both are set
				select_one (args, {'season', 'series-number', 'series-no', 'seriesnumber', 'seriesno'}, 'redundant_parameters');	
																				-- add error message
				SeriesNumber = '';												-- unset; prefer |season= over |seriesno=
			end
																				-- assemble a table of parts concatenated later into Series
			if is_set (Season) then table.insert (s, wrap_msg ('season', Season, use_lowercase)); end
			if is_set (SeriesNumber) then table.insert (s, wrap_msg ('series', SeriesNumber, use_lowercase)); end
			if 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;
			local ChapterLink = TitleLink;										-- alias episodelink
			local ChapterLinkorigin = TitleLinkorigin;
			TransChapter = TransTitle;
			ChapterURLobject = URLobject;
			
			Title = Series;														-- promote series to title
			TitleLink = SeriesLink;
			TitleLinkorigin = A:ORIGIN ('SeriesLink');
			Series = table.concat (s, sepc .. ' ');								-- this is concatenation of season, seriesno, episode number

			if is_set (ChapterLink) and not is_set (ChapterURL) then			-- link but not URL
				Chapter = make_internal_link (ChapterLink, Chapter, ChapterLinkorigin);		
																				-- ok to wikilink
			elseif is_set (ChapterLink) and is_set (ChapterURL) then			-- if both are set, URL links episode;
				Series = make_internal_link (ChapterLink, Series, ChapterLinkorigin);
																				-- series links with ChapterLink (episodelink -> TitleLink -> ChapterLink) ugly
			end
			URLobject = create_url_object ();									-- unset
			TransTitle = '';
			ScriptTitle = '';
			
		else																	-- now oddities that are cite serial
			Chapter = A['Episode'];												-- TODO: make |episode= available to cite episode someday?
			if is_set (Series) and is_set (SeriesLink) then
				Series = make_internal_link (SeriesLink, Series, A:ORIGIN ('SeriesLink'));
			end
			Series = wrap_style ('italic-title', Series);						-- series is italicized
		end	
	end
-- end of {{cite episode}} stuff

-- Account for the oddities that are {{cite arxiv}}, before generation of COinS data.
	if 'arxiv' == citation_class then
		if not is_set (ID_list['ARXIV']) then									-- |arxiv= or |eprint= required for cite arxiv
			append_error ('arxiv_missing', {});									-- add error message
		elseif is_set (Series) then												-- series is an alias of version
			ID_list['ARXIV'] = ID_list['ARXIV'] .. Series;						-- concatenate version onto the end of the arxiv identifier
			Series = '';														-- unset
			deprecated_parameter ('version');									-- deprecated parameter but only for cite arxiv
		end
		
		if first_set ({AccessDate, At, URLobject['format'], Page, Pages, PublisherName, URLobject['url'],	-- a crude list of parameters that are not supported by cite arxiv
			ID_list['ASIN'], ID_list['BIBCODE'], ID_list['DOI'], ID_list['ISBN'], ID_list['ISSN'],
			ID_list['JFM'], ID_list['JSTOR'], ID_list['LCCN'], ID_list['MR'], ID_list['OCLC'], ID_list['OL'],
			ID_list['OSTI'], ID_list['PMC'], ID_list['PMID'], ID_list['RFC'], ID_list['SSRN'], ID_list['USENETID'], ID_list['ZBL']},27) then
				append_error ('arxiv_params_not_supported', {});				-- add error message

				AccessDate= '';													-- set these to empty string; not supported in cite arXiv
				PublisherName = '';												-- (if the article has been published, use cite journal, or other)
				URLobject = create_url_object ();
				Page = ''; Pages = ''; At = '';
		end
		Periodical = 'arXiv';													-- periodical not allowed in cite arxiv; if article has been published, use cite journal
																				-- set to arXiv for COinS; after that, must be set to empty string
	end
	
-- legacy: promote concatenation of |month=, and |year= to Date if Date not set; or, promote PublicationDate to Date if neither Date nor Year are set.
	if not is_set (Date) then
		if is_set (Year) then
			Date = Year;														
			Dateorigin = A:ORIGIN ('Year');										-- promote Year to Date
			Year = nil;															-- make nil so Year as empty string isn't used for CITEREF
		elseif is_set (PublicationDate) then									-- use PublicationDate when |date= and |year= are not set
			Date = PublicationDate;												
			Dateorigin = A:ORIGIN ('PublicationDate');							-- promote PublicationDate to Date
			PublicationDate = '';
		end
	else
		if is_set (PublicationDate) and PublicationDate ~= Date then
			PublicationDate = wrap_msg ('publication-date', PublicationDate, use_lowercase);
		else
			PublicationDate = '';												-- if PublicationDate is same as Date, don't display in rendered citation
		end
	end

	local COinS_date = {};														-- holds date info extracted from |date= for the COinS metadata by Module:Date verification
	local anchor_year = validate_date (AccessDate, ArchiveDate, Date, DoiBroken, Embargo, LayDate, PublicationDate, Year, COinS_date, Dateorigin);
																				-- used in the CITEREF identifier

-- Account for the oddity that is {{cite journal}} with |pmc= set and |url= not set.  Do this after date check but before COInS.
-- Here we unset Embargo if PMC not embargoed (|embargo= not set in the citation) or if the embargo time has expired. Otherwise, holds embargo date
	Embargo = is_embargoed (Embargo);											-- 

	if citation_class == 'journal' and not is_set (URLobject['url']) and is_set (ID_list['PMC']) then
		if not is_set (Embargo) then											-- if not embargoed or embargo has expired
			URLobject['url'] =cfg.id_handlers['PMC'].prefix .. ID_list['PMC'];	-- set url to be the same as the PMC external link if not embargoed
			URLobject['origin'] = cfg.id_handlers['PMC'].parameters[1];			-- set URLorigin to parameter name for use in error message if citation is missing a |title=
		end
	end
	
	if  not is_set (URLobject['url']) then
		if in_array (citation_class, cfg.args_support['templates_requiring_url']) then		
			append_error ('cite_web_url', {});
		end
		
		-- Test if accessdate is given without giving a URL
		if is_set (AccessDate) and not is_set (ChapterURLobject['url']) then	-- ChapterURL may be set when the others are not set; TODO: move this to a separate test?
			append_error ('accessdate_missing_url', {});
			AccessDate = '';
		end
	end

-- At this point fields may be nil if they weren't specified in the template use.  We can use that fact.
	-- Test if citation has no title
	if	not is_set (Title) and
		not is_set (TransTitle) and
		not is_set (ScriptTitle) then
			if 'episode' == citation_class then									-- special case for cite episode; TODO: is there a better way to do this?
				append_error ('citation_missing_title', {'series'});
			else
				append_error ('citation_missing_title', {'title'});
			end
	end
	
	if 'none' == Title and citation_class == 'journal' then						-- special case for journal cites
		Title = '';																-- set title to empty string
		add_maint_cat ('untitled');
	end

	check_for_external_link ({															-- add error message when any of these parameters contains a URL
		['title'] = Title,
		[A:ORIGIN ('Chapter')] = Chapter,
		[A:ORIGIN ('Periodical')] = Periodical,
		[A:ORIGIN ('PublisherName')] = PublisherName,
		});

	-- COinS metadata (see <http://ocoins.info/>) for automated parsing of citation information.
	-- handle the oddity that is cite encyclopedia and {{citation |encyclopedia=something}}. Here we presume that
	-- when Periodical, Title, and Chapter are all set, then Periodical is the book (encyclopedia) title, Title
	-- is the article title, and Chapter is a section within the article.  So, we remap 
	
	local coins_chapter = Chapter;												-- default assuming that remapping not required
	local coins_title = Title;													-- et tu
	if 'encyclopaedia' == citation_class then
		if is_set (Chapter) and is_set (Title) and is_set (Periodical) then		-- if all are used then
			coins_chapter = Title;												-- remap
			coins_title = Periodical;
		end
	end

	-- this is the function call to COinS()
	local OCinSoutput = COinS ({
		['Periodical'] = Periodical,
		['Encyclopedia'] = Encyclopedia,
		['Chapter'] = coins_chapter,
		['ScriptChapter'] = ScriptChapter,
		['Map'] = Map,
		['Degree'] = Degree;													-- cite thesis only
		['Title'] = coins_title,
		['ScriptTitle'] = ScriptTitle,
		['PublicationPlace'] = PublicationPlace,
		['Date'] = COinS_date.rftdate,											-- COinS_date has correctly formatted date if Date is valid;
		['Season'] = COinS_date.rftssn,
		['Chron'] =  COinS_date.rftchron or (not COinS_date.rftdate and Date) or '',	-- chron but if not set and invalid date format use Date; keep this last bit?
		['Series'] = Series,
		['Volume'] = Volume,
		['Issue'] = Issue,
		['Pages'] = first_set ({Sheet, Sheets, Page, Pages, At}, 5),			
		['Edition'] = Edition,
		['PublisherName'] = PublisherName,
		['URL'] = first_set ({ChapterURLobject['url'], URLobject['url']}, 2),
		['Authors'] = NameList,
		['ID_list'] = ID_list,
		['RawPage'] = this_page.prefixedText,
	}, config.CitationClass);

-- Account for the oddities that are {{cite arxiv}}, AFTER generation of COinS data.
	if 'arxiv' == citation_class then											-- we have set rft.jtitle in COinS to arXiv, now unset so it isn't displayed
		Periodical = '';														
	end

-- special case for cite newsgroup.  Do this after COinS because we are modifying Publishername to include some static text
	if 'newsgroup' == citation_class then
		if is_set (PublisherName) then
			PublisherName = wrap_msg ('newsgroup', make_external_link ('news:' .. PublisherName, PublisherName, A:ORIGIN ('PublisherName')), use_lowercase);
		end
	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.
	
	-- apply |[xx-]format= styling; at the end, these parameters hold correctly styled format annotation,
-- an error message if the associated url is not set, or an empty string for concatenation
	format_format ({ArchiveURLobject, ConferenceURLobject, URLobject, LayURLobject, TranscriptURLobject, ChapterURLobject});
	
-- special case for chapter format so no error message or cat when chapter not supported
	if format_url_access_text (URLobject, SubscriptionRequired, RegistrationRequired) then
		select_one (args, {'url-access', 'urlaccess', 'registration', 'subscription'}, 'redundant_parameters');
	end																			-- 只需其一
	format_url_access_text (ChapterURLobject, nil, nil);

	local OriginalURLobject;													-- TODO: swap chapter and title here so that archive applies to most specific if both are set?
	OriginalURLobject, URLobject, ChapterURLobject =
		swap_urls (URLobject, ChapterURLobject, ArchiveURLobject, DeadURL);
	
	local chapter_no_quotes = false;											-- default assume that we will be quoting the chapter parameter value
	if is_set (Contribution) and has_contributors then							-- if this is a contribution with contributor(s)
		if in_array (Contribution:lower(), cfg.keywords['contribution']) then	-- and a generic contribution title
			chapter_no_quotes = true;											-- then render it unquoted
		end
	end
	Chapter = format_chapter_title (ScriptChapter, Chapter, TransChapter, ChapterURLobject, chapter_no_quotes, citation_class, TitleType, sepc);		
																				-- Contribution is also in Chapter
	-- Format main title.
	Title, URLobject = format_main_title (Title, TitleLink, TitleLinkorigin, ScriptTitle, TransTitle, URLobject, no_chapter_format, citation_class, Periodical);
	Place = pend_separator (wrap_msg ('written', Place, use_lowercase), sepc, false);
	Conference = format_conference (Conference, ConferenceURLobject, Periodical, citation_class, sepc);
	local Insource_location = format_insource_location (Page, Pages, Sheet, Sheets, At, Minutes, Time, TimeCaption, Section, Sections, Inset, citation_class, Periodical_origin, sepc, NoPP, use_lowercase);
	Language = language_parameter (Language);									-- format, categories, name from ISO639-1, etc

	Others = pend_separator (Others, sepc, true);
	Others = pend_separator (wrap_msg ('translated', Translators, use_lowercase), sepc, true) .. Others;
	
	if 'speech' ~= citation_class then 
		TitleNote = pend_separator (TitleNote, sepc, true);
	end
	
	Edition = wrap_msg ('edition', Edition, use_lowercase);
	Series = pend_separator (Series, sepc, true);
	OrigYear = wrap_msg ('orig year', OrigYear, use_lowercase);
	Agency = pend_separator (Agency, sepc, true);
	Volume = format_volume_issue (Volume, Issue, citation_class, Periodical_origin, sepc, use_lowercase);

	------------------------------------ totally unrelated data
	
	Via = wrap_msg ('via', Via, use_lowercase);
	AccessDate = format_accessdate (AccessDate, sepc, use_lowercase);
	ID = format_id (ID, Docket, sepc, use_lowercase);
	ID_list = build_id_list (ID_list, {IdAccessLevels=ID_access_levels, DoiBroken = DoiBroken, ASINTLD = ASINTLD, IgnoreISBN = IgnoreISBN, Embargo=Embargo, Class = Class});

	local URL = '';
	if is_set (URLobject['url']) then
		URL = ' ' .. make_external_link (URLobject['url'], nil, URLobject['origin']) .. URLobject['access-text'];
	end
	
	local Format = URLobject['format'];
	Quote = format_quote (Quote, sepc);
	local Archived = format_archive (ArchiveURLobject, OriginalURLobject, ArchiveDate, DeadURL, sepc, use_lowercase);
	local Lay = format_lay (LayURLobject, LayDate, LaySource, sepc, use_lowercase);
	Transcript = format_external_link (Transcript, TranscriptURLobject, sepc);
	local Publisher = format_publisher (PublisherName, PublicationPlace, Periodical, citation_class, sepc);

	local use_in = is_set (Chapter) and (not has_contributors);
	Authors, Editors, Contributors = format_people (Authors, Editors, Contributors, multiple_editors, use_in, sepc);
	
	-- Several of the above rely upon detecting this as nil, so do it last.
	Periodical = format_periodical (Periodical, Title, TitleNote, sepc);

	-- 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;
	local tcommon2;																-- used for book cite when |contributor= is set
	
	if citation_class == 'journal' and is_set (Periodical) then
		Others = pend_separator (Others, sepc, false);
		tcommon = safe_join ({Others, Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Edition, Publisher, Agency}, sepc);
		
	elseif contributors_valid then												-- special cases for book cites where contributors are allowed
		if is_set (Contributors) then											-- when we are citing foreword, preface, introduction, etc
			tcommon = safe_join ({Title, TitleNote}, sepc);						-- author and other stuff will come after this and before tcommon2
			tcommon2 = safe_join ({Conference, Periodical, Format, TitleType, Series, Volume, Others, Edition, Publisher, Agency}, sepc);
		else
			tcommon = safe_join ({Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Volume, Others, Edition, Publisher, Agency}, sepc);
		end
	elseif 'map' == citation_class then											-- special cases for cite map
		if is_set (Chapter) then												-- map in a book; TitleType is part of Chapter
			tcommon = safe_join ({Title, Format, Edition, Scale, Series, Cartography, Others, Publisher, Volume}, sepc);
		elseif is_set (Periodical) then											-- map in a periodical
			tcommon = safe_join ({Title, TitleType, Format, Periodical, Scale, Series, Cartography, Others, Publisher, Volume}, sepc);
		else																	-- a sheet or stand-alone map
			tcommon = safe_join ({Title, TitleType, Format, Edition, Scale, Series, Cartography, Others, Publisher}, sepc);
		end
		
	elseif 'episode' == citation_class then										-- special case for cite episode
		tcommon = safe_join ({Title, TitleNote, TitleType, Series, Transcript, Edition, Publisher}, sepc);
	else																		-- all other CS1 templates
		tcommon = safe_join ({Title, TitleNote, Conference, Periodical, Format, TitleType, Series, 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
	local xDate;
	if (is_set (Periodical) and is_set (Date) and
		not in_array (citation_class, {'encyclopaedia', 'web'}))
		or (in_array (citation_class, {'book', 'news'})) then
		if in_array (citation_class, {'journal', 'citation'}) and is_set (Volume) then
			xDate = safe_join ({Date .. ',' .. Volume, Insource_location, PublicationDate, OrigYear, AccessDate}, sepc);
		else
			xDate = safe_join ({Date, Insource_location, PublicationDate, OrigYear, AccessDate}, sepc);
		end
		Insource_location = ''
	else
		xDate = safe_join ({Date, PublicationDate, OrigYear, AccessDate}, sepc);
	end
	xDate = pend_separator (xDate, sepc, true);
	-- END LOCAL

	local idcommon = safe_join ({URL, xDate, ID_list, Archived, Via, Lay, Language, Quote}, sepc);
	local text;
	if is_set (Authors) then
		if is_set (Contributors) then
			text = safe_join ({Contributors, Chapter, tcommon, Authors, Place, Editors, tcommon2, Insource_location, idcommon }, sepc);
		else
			text = safe_join ({Authors, Chapter, Place, Editors, tcommon, Insource_location, idcommon }, sepc);
		end
	else
		text = safe_join ({Editors, Chapter, Place, tcommon, Insource_location, idcommon}, sepc);
	end
	
	if 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);
	end	
	
	text = safe_join ({text, PostScript}, sepc);

	-- Now enclose the whole thing in a <cite/> element
	return format_citation (text, config.CitationClass, Ref, NameList, anchor_year, OCinSoutput, no_tracking_cats);
end

--[[--------------------------< V A L I D A T E >--------------------------------------------------------------
Looks for a parameter's name in the whitelist.

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

local function validate (name)
	local name = tostring (name);
	local state = whitelist.basic_arguments[name];
	
	-- Normal arguments
	if true == state then return true; end										-- valid actively supported parameter
	if false == state then
		deprecated_parameter (name);											-- parameter is deprecated but still supported
		return true;
	end
	
	-- Arguments with numbers in them
	name = name:gsub ('%d+', '#');												-- replace digit(s) with # (last25 becomes last#
	state = whitelist.numbered_arguments[name];
	if true == state then return true; end										-- valid actively supported parameter
	if false == state then
		deprecated_parameter (name);											-- parameter is deprecated but still supported
		return true;
	end
	
	return false;								-- Not supported because not found or name is set to nil
end

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

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

]]

function citation (frame)
	local pframe = frame:getParent();
	local module_path = 'Module:Citation/CS1/'
	local module_suffix = frame:getTitle():gsub ('^Module:Citation/CS1', ''); 
	
	load_modules (module_path, module_suffix);
	
	local args = {};
	local suggestions = {};
	local error_reported = false;

	local config = {};
	for k, v in pairs (frame.args) do
		config[k] = v;
		args[k] = v;	   
	end	

	local capture;																-- the single supported capture when matching unknown parameters using patterns
	for k, v in pairs (pframe.args) do
		if v ~= '' then
			if not validate (k) then			
				error_reported = false;
				if type (k) ~= 'string' then
					-- Exclude empty numbered parameters
					if v:match ('%S+') ~= nil then
						append_error ('text_ignored', {v});
						error_reported = true;
					end
				elseif validate (k:lower()) then 
					append_error ('parameter_ignored_suggest', {k, k:lower()});
					error_reported = true;
				else
					if nil == suggestions.suggestions then						-- if this table is nil then we need to load it
						suggestions = mw.loadData (module_path .. 'Suggestions' .. module_suffix);
					end
					for pattern, param in pairs (suggestions.patterns) do		-- loop through the patterns to see if we can suggest a proper parameter
						capture = k:match (pattern);							-- the whole match if no caputre in pattern else the capture if a match
						if capture then											-- if the pattern matches 
							param = substitute (param, capture);				-- add the capture to the suggested parameter (typically the enumerator)
							append_error ('parameter_ignored_suggest', {k, param});
																				-- set the error message
							error_reported = true;
							break;
						end
					end
					if not error_reported then									-- couldn't match with a pattern, is there an expicit suggestion?
						if suggestions.suggestions[k:lower()] ~= nil then
							append_error ('parameter_ignored_suggest', {k, suggestions.suggestions[k:lower()]});
							error_reported = true;
						else
							append_error ('parameter_ignored', {k});
							error_reported = true;
						end
					end
				end
			end
			args[k] = v;
		elseif args[k] ~= nil or (k == 'postscript') then
			args[k] = v;
		end		
	end	
	local error_msg;
	for k, v in pairs (args) do
		if 'string' == type (k) then											-- don't evaluate positional parameters
			error_msg = has_invisible_chars (k, v);
			if is_set (error_msg) then
				append_error ('invisible_char', error_msg);
			end
		end
	end
	return do_citation (config, args)
end

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

return {citation = citation};