Mô đun:Check isxn

--[[This code is derived from the ISXN validation code at Module:Citation/CS1.  It allows validating ISBN,ISMN, and ISSN without invoking a citation template.]]local p = {}--[[--------------------------< E R R _ M S G _ S U P L _ T >--------------------------------------------------error message supplements for check_isbn(); adapted from a similarly named table at Module:Citation/CS1/Configuration]]local err_msg_supl_t = {	['char'] = 'invalid character',	['check'] = 'checksum',	['form'] = 'invalid form',	['group'] = 'invalid group id',	['length'] = 'length',	['prefix'] = 'invalid prefix',	}--[[--------------------------< IS _ V A L I D _ I S X N >-----------------------------------------------------ISBN-10 and ISSN validator code calculates checksum across all isbn/issn digits including the check digit. ISBN-13 is checked in check_isbn().If the number is valid the result will be 0. Before calling this function, issbn/issn must be checked for length and stripped of dashes,spaces and other non-isxn characters.]]local function is_valid_isxn (isxn_str, len)	local temp = 0;	isxn_str = { isxn_str:byte(1, len) };	-- make a table of byte values '0' → 0x30 .. '9'  → 0x39, 'X' → 0x58	len = len+1;							-- adjust to be a loop counter	for i, v in ipairs( isxn_str ) do		-- loop through all of the bytes and calculate the checksum		if v == string.byte( "X" ) then		-- if checkdigit is X (compares the byte value of 'X' which is 0x58)			temp = temp + 10*( len - i );	-- it represents 10 decimal		else			temp = temp + tonumber( string.char(v) )*(len-i);		end	end	return temp % 11 == 0;					-- returns true if calculation result is zeroend--[[--------------------------< IS _ V A L I D _ I S X N  _ 1 3 >----------------------------------------------ISBN-13 and ISMN validator code calculates checksum across all 13 isbn/ismn digits including the check digit.If the number is valid, the result will be 0. Before calling this function, isbn-13/ismn must be checked for lengthand stripped of dashes, spaces and other non-isxn-13 characters.]]local function is_valid_isxn_13 (isxn_str)	local temp=0;		isxn_str = { isxn_str:byte(1, 13) };										-- make a table of byte values '0' → 0x30 .. '9'  → 0x39	for i, v in ipairs( isxn_str ) do		temp = temp + (3 - 2*(i % 2)) * tonumber( string.char(v) );				-- multiply odd index digits by 1, even index digits by 3 and sum; includes check digit	end	return temp % 10 == 0;														-- sum modulo 10 is zero when isbn-13/ismn is correctend--[[--------------------------< C H E C K _ I S B N >------------------------------------------------------------Determines whether an ISBN string is valid.  Implements an ISBN validity check for {{ISBN}}, {{ISBNT}}, {{SBN}}, and{{Format ISBN}}.]]local function check_isbn (isbn_str, frame)	local function return_result (check, err_type)								-- local function to render the various error returns		if not check then														-- <check> false when there is an error			local template = ((frame.args.template_name and '' ~= frame.args.template_name) and frame.args.template_name) or nil;	-- get template name			if not template then				return '<span class="error" style="font-size:100%">&nbsp;calling template requires template_name parameter</span>';			end			local out_t = {'<span class="error" style="font-size:100%">'};		-- open the error message span			table.insert (out_t, '&nbsp;Parameter error in {{[[Template:');		-- open 'template' markup; open wikilink with Template namespace			table.insert (out_t, template);										-- template name wikilink			table.insert (out_t, '|');											-- its pipe			table.insert (out_t, template);										-- wikilink label			table.insert (out_t, ']]}}:&nbsp;');								-- close wikilink; close 'template' markup			table.insert (out_t, err_type);										-- type of isbn error			table.insert (out_t, '</span>')										-- close the error message span			if 0 == mw.title.getCurrentTitle().namespace then					-- categorize only when this template is used in mainspace				local category = table.concat ({'[[Category:Pages with ISBN errors]]'});				table.insert (out_t, category);			end			return table.concat (out_t);										-- make a big string and done		end	return '';																	-- no error, return an empty string	end	if nil ~= isbn_str:match ('[^%s-0-9X]') then		return return_result (false, err_msg_supl_t.char);						-- fail if isbn_str contains anything but digits, hyphens, or the uppercase X	end	local id = isbn_str:gsub ('[%s-]', '');										-- remove hyphens and whitespace	local len = id:len(); 	if len ~= 10 and len ~= 13 then		return return_result (false, err_msg_supl_t.length);					-- fail if incorrect length	end	if len == 10 then		if id:match ('^%d*X?$') == nil then										-- fail if isbn_str has 'X' anywhere but last position			return return_result (false, err_msg_supl_t.form);											end		if id:find ('^63[01]') then												-- 630xxxxxxx and 631xxxxxxx are (apparently) not valid isbn group ids but are used by amazon as numeric identifiers (asin)			return return_result (false, err_msg_supl_t.group);					-- fail if isbn-10 begins with 630/1		end		return return_result (is_valid_isxn (id, 10), err_msg_supl_t.check);	-- pass if isbn-10 is numerically valid (checksum)	else		if id:match ('^%d+$') == nil then			return return_result (false, err_msg_supl_t.char);					-- fail if ISBN-13 is not all digits		end		if id:match ('^97[89]%d*$') == nil then			return return_result (false, err_msg_supl_t.prefix);				-- fail when ISBN-13 does not begin with 978 or 979		end		if id:match ('^9790') then			return return_result (false, err_msg_supl_t.group);					-- group identifier '0' is reserved to ISMN		end		return return_result (is_valid_isxn_13 (id), err_msg_supl_t.check);		-- pass if isbn-10 is numerically valid (checksum)	endend--[[--------------------------< C H E C K _ I S M N >------------------------------------------------------------Determines whether an ISMN string is valid.  Similar to isbn-13, ismn is 13 digits begining 979-0-... and uses thesame check digit calculations.  See http://www.ismn-international.org/download/Web_ISMN_Users_Manual_2008-6.pdfsection 2, pages 9–12.]]local function check_ismn (id, error_string)	local text;	local valid_ismn = true;	id=id:gsub( "[%s-–]", "" );													-- strip spaces, hyphens, and endashes from the ismn	if 13 ~= id:len() or id:match( "^9790%d*$" ) == nil then					-- ismn must be 13 digits and begin 9790		valid_ismn = false;	else		valid_ismn=is_valid_isxn_13 (id);										-- validate ismn	end	return valid_ismn and '' or error_stringend--[[--------------------------< I S S N >----------------------------------------------------------------------Validate and format an issn.  This code fixes the case where an editor has included an ISSN in the citation but has separated the two groups of fourdigits with a space.  When that condition occurred, the resulting link looked like this:	|issn=0819 4327 gives: [http://www.worldcat.org/issn/0819 4327 0819 4327]  -- can't have spaces in an external link	This code now prevents that by inserting a hyphen at the issn midpoint.  It also validates the issn for length and makes sure that the checkdigit agreeswith the calculated value.  Incorrect length (8 digits), characters other than 0-9 and X, or checkdigit / calculated value mismatch will all cause a check issnerror message.]]local function check_issn(id, error_string)	local issn_copy = id;		-- save a copy of unadulterated issn; use this version for display if issn does not validate	local text;	local valid_issn = true;	if not id:match ('^%d%d%d%d%-%d%d%d[%dX]$') then		return error_string;	end		id=id:gsub( "[%s-–]", "" );									-- strip spaces, hyphens, and endashes from the issn	if 8 ~= id:len() or nil == id:match( "^%d*X?$" ) then		-- validate the issn: 8 digits long, containing only 0-9 or X in the last position		valid_issn=false;										-- wrong length or improper character	else		valid_issn=is_valid_isxn(id, 8);						-- validate issn	end	return valid_issn and '' or error_stringend------------------------------< E N T R Y   P O I N T S >--------------------------------------------------====function p.check_isbn(frame)	return check_isbn(frame.args[1] or frame:getParent().args[1], frame)endfunction p.check_ismn(frame)	return check_ismn(frame.args[1] or frame:getParent().args[1], frame.args['error'] or frame:getParent().args['error'] or 'error')endfunction p.check_issn(frame)	return check_issn(frame.args[1] or frame:getParent().args[1], frame.args['error'] or frame:getParent().args['error'] or 'error')endreturn p